CA2038583C

CA2038583C - Information recording and reproducing device

Info

Publication number: CA2038583C
Application number: CA002038583A
Authority: CA
Inventors: Shigemi Maeda; Kunio Kojima; Kazuaki Okumura; Shigeo Terashima
Original assignee: Sharp Corp
Current assignee: Sharp Corp
Priority date: 1990-03-20
Filing date: 1991-03-19
Publication date: 1996-03-12
Anticipated expiration: 2011-03-19
Also published as: DE69119631D1; CA2038583A1; KR950000130B1; EP0448378B1; EP0448378A2; EP0448378A3; US5434991A; DE69119631T2; KR910017373A

Abstract

An information recording and reproducing device uses a recording medium which is provided with units composed of blocks and a unit information recording area. The recording area contains unit allocation information, sector number information indicating the number of sectors per unit, and unit number information identifying each unit. When the recording medium is placed in the device, the respective information is read by a calculating unit and is used forcalculating physical sector numbers corresponding to a block specified in recording and reproduction operations. Access operations are performed to the calculated sectors, which allows the desired information to be recorded. The block includesdummy sectors which are added before and after each group of a predetermined number of effective sectors. When high-volume information is recorded over several blocks, the dummy sectors may be provided only for the first and last blocks. The device records a group of information whose volume varies from the smallest block number toward the larger block numbers, while it records a group of information whose volume is fixed from the largest block number. Thus, the recording area iseffectively used. The device easily conducts the information management when a host device specifies a block. The file management may be executed by providing a unit for recording file management information separately from a unit for recording files.

Description

_ INFORMATION RECORDING AND REPRODUCING DEVICE
.

The present invention relates to an information recording and reproducing device which records and reproduces various forms of information on recordable recording media such as various types of rewritable optical disks using the so-called non-complete interleaving method.
Conventionally, so-called compact disks (hereinafter referred to as CDs) have been used widely, on which successive data such as musical information is recorded as digital signals in the form of optically-detectable minute pits. The information on the CDs is reproducible through CD players.
Figures 18 and 19 are schematic views illustrating a signal format to be used in the CDs. As shown in Figure 18, a frame 31a of a recording signal format to be used in the CDs. As shown in Figure 18, a frame 31a of a recording signal is composed of a frame synchronization signal 31b indicating the start of the frame, a sub-code 31c (described later) which has additional data information, and a data field 31d comprising 24 bytes of main data and 8 bytes of error detection and correction parity added thereto. Errors in the datafield 31d are detected and corrected based on an error detection and correction method employing a non-complete interleaving method, called Cross Interleaved Reed Solomon Code (CIRC).
As shown in Figure 19, sub-codes 31c of 98 frames form a sub-coding block 32c. The 98 frames form a sector 32a (one sub-coding frame).
Track numbers (the numbers of pieces of music if the data is musical information) and absolute address information on the disk are determined based on the sub-coding block 32c. A frame synchronization signal 32b and a data field 32d respectively include 98 frames of the synchronization signals 31b and data fields 31d of Figure 18.
If the length of the sector 32a, i.e. a sector length, equals for example 13.3 (ms), 75 sectors equal one second. In this case, sector numbers on the disk can be described as a function of time, "minute": "second": "a sector number in one second" (i.e. taking a value from 0 to 74), and the sector ,,rA,~
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numbers form time information and address information which consecutively increase from the inside to the outside of the disk.
Figure 17 is a typical depiction illustrating allocation of area on the CD. A disk 33 comprises a main information recording area 33a and a Table Of Contents (TOC) area 33b (shown by hatching for convenience' sake). The main information recording area 33a stores main information such as musical information and sub-code sector numbers, and the TOC area 33b stores sub-code additional information relating to respective information recorded in the main information recording area 33a, such as the track number and the recording start sector number of each track.
According to the format, when the disk 33 is placed into the CD
player, sub-code information in the TOC area 33b is read. From that the number of main information pieces (equivalent to the number of musical pieces in the case of musical information) and sector numbers indicating the recording start positions of the respective main information pieces are recognized. Accessto a desired track is promptly carried out upon receiving instructions to perform a reproduction operation by verifying that the sub-code information read out from the TOC area 33b coincides with the sub-code sector number recorded in the main information recording area 33a.
In the CD, since information is recorded in the Constant Linear Velocity (hereinafter referred to as CLV) method, the recording density is uniform independently of any radius location on the disk 33, thereby permitting the recording volume to increase. During the reproduction in the CD player, actually the CLV control is achieved by, for example, controlling the rotation of the disk 33 so that the interval of the frame synchronization signals in a reproduced signal from the CD recorded in the signal format equals a reference value.
In cases where various types of information, including musical information and computer information, have been recorded on rewritable optical disks such as magneto-optical disks that have been developed recently, it is desirable to provide an information recording and reproducing device having a ~A' compatible reproduction method with the conventional CDs and Compact Disk Read Only Memory (CD-ROM).
In this case, especially for an optical disk whereon no information is recorded, absolute addresses using a sub-code in the signal format for CD
5 and frame synchronization signals which can be used for the CLV control do notexist. Consequently, access operations to desired sectors cannot be executed before recording operations, and the CLV control required during recording and reproduction cannot be achieved.
To counteract the above problem, the following method for 10 recording absolute addresses with using sub-codes was suggested. In this method, absolute addresses go through a bi-phase mark modulation process, and guiding grooves of an optical disk are deviated inward or outward in a radial direction of the disk, or the widths of the guiding grooves are varied accordingto "0" or "1" of the respective bits (see U.S. Patent No. 4,907,216).
In the method, if the frequency band of absolute addresses having gone through the bi-phase mark modulation process varies from the frequency band of recording information having gone through the Eight to Fourteen Modulation (EFM) process, it is possible to reproduce them individually. In addition, access operations to portions wherein no recording information is contained can be performed by using the absolute addresses which were recorded by, for example, deviating the guiding grooves of the disk. As for the CLV control, an accurate velocity control is fulfilled by using reproduction carrier components of the absolute addresses, and the CLV control can also be performed in recording operations.
Rewritable optical disks having compatibility with CDs are expected to be used, especially in typical families, as high-density information recording media whereon various kinds of information such as music, text and image information can be recorded.
For example, the rewritable optical disks may be used as recording media for electronic still cameras, whereon voice information can be recorded.

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20~8583 Conventionally, electronic still cameras having an ability to record some comments on each still picture, use so-called floppy disks as recording media. Therefore, in case rewritable optical disks are used as recording media, image and voice information may be allocated on the disks in the same way as 5 the floppy disks.
As shown in Figure 20, in a method for allocating image and voice information, image information recording areas 11, 12 ... (the volume as a function of time is, for example three to four seconds per picture) and voice information recording areas A1, A2 ... (for example about ten seconds per 10 picture) can be allocated alternatively in the recording area, and the capacity of the respective voice information recording areas A1,A2... per picture can be fixed.
In this case, however, some problems may arise, for instance, the utility factor of the voice information recording areas A1,A2... decreases when 15 the actual voice information is shorter than the voice information recording areas A1,A2..., or on the contrary, the actual voice information can not be stored in the respective information recording areas. When no voice information is recorded, the utility factor drops by an especially large amount.
To counteract the above kind of problem, as shown in Figure 21 the image information recording areas 11, 12 ... and the voice information recording areas A1, A2... are allocated alternatively, and the capacity of the voice information recording areas A1,A2...is varied, so that a desired length of voice information can be recorded for each still picture.
In this case, however, the utility factor of the recording area can be improved when one restriction is imposed upon rewriting voice information.
That restriction is that, since image information recorded on latter portions needs to be protected, new voice information to be recorded cannot be longer than the formerly-recorded voice information.
Moreover, when unnecessary voice information is erased, blank 30 areas which were the prior voice information recording areas A1, A2 ... are presented. However, since the length of each area is different from others, if ''s~i`~' image information is recorded in the areas, the utility factor becomes low and the address management becomes complicated.
In the meantime, when rewriting information by the use of the signal format for CD, a piece of information recorded in a target physical sector 5 is actually divided into a plurality of pieces and recorded in various sectors on the disk by CIRC. Therefore, it is difficult to rewrite information by only rewriting the desired sector. In fact, data desired to be rewritten and data recorded justbefore and after the desired data are stored in the same sector on the disk, andthe connection in error correction between the data is given between the 10 respective data. Therefore, it is difficult to keep the connection in the case where only the desired data is rewritten (see Japanese published Patent OfficialGazette, Tokukaihei 1-55787, for more details). In other words, all the recording information is recorded successively in the CD format; however, if a part of recorded data is rewritten, the connection in error correction between the data 15 and data recorded just before and after the recorded data is lost in the vicinity of the recording start and end positions of the rewritten data, causing frequentreproduction errors. The reasons of this is that since the minimum access unit to the information recording position is a sector, sectors to which the user cannot access exist in front and after the rewritten information. As a result, the 20 utility factor of the disk decreases.
In order to prevent such reproduction errors from occurring, for example, additional sectors wherein dummy data is recorded may be provided before and after data to be actually recorded and reproduced. The dummy data comprises parity codes for correcting errors which may occur in the leading and 25 ending parts of the data. For example, in the case of CD format, to demonstrate the full correction ability of CIRC, i.e. to transmit codes in the non-complete interleaving method, 105 frames are required. Therefore, it is desirable to provide (105/98) . 1.07 sectors each before and after a sector comprising 98 frames. i.e. two additional sectors each practically. The 30 additional sectors can be used as sectors where a Phase Locked Loop (PLL) ~r~
~' can execute pull-in operations. However, providing the additional sectors resultin the decrease in the utility factor of the disk.
In order to carry out address management more easily when rewriting information, a predetermined number of the sectors taken together 5 each form a block, and for example, two additional sectors described above may be provided at the start and end of each block so as to rewrite information block-by-block (hereinafter referred to as " by the block unit").
However, if the additional sectors are provided for every block, when high-volume data is recorded in a number of sectors, the respective 10 additional data needs to be recorded in each additional sector provided for the blocks. Consequently, the utility factor of the disk and the data transmission speed drop.
To restrain the drop in the utility factor of the disk caused by providing additional sectors to a minimum degree, the number of sectors 15 forming a minimum unit for rewriting a piece of information (hereinafter referred to as a block) should be increased. As a result, the utility factor of the disk comes close to the primary utility factor of CDs. However, it is unsuitable to form blocks composed of sufficiently large numbers of sectors for every kind of information, for example, low-volume data such as text information; also, the 20 time taken for recording is wastefully prolonged.
Arranging the block sizes (the number of sectors per block) as set out above has both its merits and drawbacks, according to the content of the information to be recorded. When the CLV format for CDs is adopted, if a recording operation and a reproduction for verification are repeatedly performed25 by the block unit, the wait time between the completion of the recording operation and the start of the reproduction operation for verification is undesirably prolonged at an outer part of the disk, especially when the length of one block is shorter than the time taken for one disk rotation.
In order to explain the above, the time chart of Figure 22 shows 30 an example of a recording operation and a reproduction operation for verification successively performed by the block unit by using a conventional disk whereon '~

- 20~8583 recording can be executed in the CLV method. The periods shown by to and tn in the figure indicate time required for each rotation of the disk at respectiveinformation positions; WO indicates a recording operation to block No. 0 locatedin the innermost part of the disk, Wn a recording operation to block No. n 5 located in the outmost part thereof, and Rn a reproduction operation for verification to block No. n after the recording operation.
The wait time for rotating the disk to the reproduction operation for verification after the recording operation is obtained by subtracting the operation time WO (or Wn) from the time to (or tn) required for one disk rotation. It can be 10 seen from Figure 22 that the wait time for rotating the disk in an outer part of the disk shown in (b) is longer than the wait time in an inner part thereof shown in (a). In other words, the information volume per time, i.e. the data transmission rate, decreases at outer parts of the disk.
To a host device (so-called personal computer) for managing 15 various types of information, in general it is desirable to perform a recording or a reproducing operation using a sector unit or a block unit like on conventionalfloppy disks and hard disks. However, in the case of the above format, additional sectors, for example two sectors, are respectively required before and after the sectors in each recording operation. Therefore, it is necessary to 20 transmit sectors corresponding to the additional sectors together. Besides, in the case of rewriting information, it is necessary to manage both sectors which can be used as data areas and additional sectors which cannot be so used, thereby causing the management to be complicated.
In the case of a high volume of information such as digital and 25 musical information, large numbers of sectors are required for recording the information. Therefore, even in cases where additional sectors are not provided, only a minor problem occurs, i.e. the leading and ending parts of the information are slightly broken. In the case of musical information, the information is not much aurally affected. On the contrary, in the case of digital 30 information or the like where small numbers of sectors are required for recording .~

- 2038~83 the information, additional sectors generally need to be provided. Thus, variousproblems arise as described above.
It is an object of the invention to record and reproduce information by specifying block numbers and to manage the information by specifying the addresses by the block unit, without providing additional sectors required for recording and reproduction in the non-complete interleaving method.
In order to achieve the object, an information recording and reproducing device of the present invention comprises operation means for calculating physical sector numbers based on a block number given to each block, and recording means for recording information based on the physical sector numbers given by the calculation. Each block is composed of a predetermined number of the effective sectors and dummy sectors respectively provided before and after the effective sectors.
According to the arrangement, a host device connected to the information recording and reproducing device can direct the information recording and reproducing device to perform a recording or a reproducing operation by only specifying the block numbers of blocks where information is to be recorded or reproduced. The information management of the information recording and reproducing device can be conducted easily as the host device specifies block addresses.
Another object of the present invention is to use recording area effectively by classifying information into two groups: a group of information whose volume varies and a group of information whose volume is fixed, and by recording them successively.
In order to achieve the object, another information recording and reproducing device of the present invention comprises recording control means for recording a group of information whose volume varies from the smallest block number toward the larger block numbers in due order, and for recording a group of information whose volume is fixed in the reverse order.
In this arrangement, when only the group of information whose volume varies is erased en bloc, successive blank areas are presented. Then, the group of information whose volume is fixed can be effectively recorded in the blank areas. Regarding information whose volume varies, only one blank area is presented between the group of information whose volume varies and the group of information whose volume is fixed. Consequently, the effective use 5 of the recording area is realized.
Another object of the present invention is to record various types of information in blocks composed of the optimum numbers of sectors according to the respective data length by providing blocks composed of different numbers of sectors on a single recording medium.
In order to achieve this object, an information recording and reproducing device of the present invention employs a recording medium whereon units and a unit information recording area are provided. The units are collections of blocks composed of predetermined numbers of the sectors (the block is the minimum unit). The unit information recording area contains: unit 15 allocation information; and sector number information indicating the number of sectors forming one block in each unit.
The device comprises means for determining physical sector numbers corresponding to the blocks in a unit which is specified when performing recording and reproducing operations based on the above-mentioned 20 respective information read out at the time the recording medium is loaded.
According to the arrangement, various types of information can be recorded in appropriate blocks on a recording medium according to the data length of the respective information. As a result, the recording area of the recording medium can be used effectively, permitting the average recording and 25 reproducing speed to increase.
Additionally, file management may be carried out by providing a unit wherein file management information is recorded, separately from a unit wherein the files are recorded.
Another object of the present invention is to improve the utility 30 factor of a recording medium when recording high-volume information in a 20~858~

number of blocks, by adding predetermined numbers of the front and rear additional data only to the first and last blocks.
In order to achieve the object, an information recording and reproducing device of the present invention comprises means for providing 5 dummy sectors before and after each block when recording low-volume data and for adding predetermined numbers of the front and rear additional data only to the first and last blocks when recording high-volume data, wherein the block is composed of predetermined numbers of the effective sectors, and dummy sectors provided before and after the group of effective sectors.
According to this arrangement, since additional data is added according to the volume of the data during recording operations, the utility factor of the recording medium can improve.
For a fuller understanding of the nature and advantages of the invention, reference should be made to the ensuing detailed description taken 15 In conjunction with the accompanying drawings.
Figure 1 to Figure 16 shows an embodiment of the present invention in detail.
Figure 1(a) is an explanatory view illustrating the relationship between block numbers, physical sector numbers and recording information 20 when recording low-volume information.
Figure 1(b) is an explanatory view illustrating the relationship between block numbers, physical sector numbers and recording information when recording high-volume information.
Figure 1(c) is an explanatory view illustrating the relationship 25 between block numbers, physical sector numbers and recording information when recording successive information.
Figure 2 is a time chart illustrating the flow of information when recording low-volume information.
Figure 3 is a time chart illustrating the flow of information when 30 recording high-volume information.

~, Figure 4 is a block diagram illustrating an information recording and reproducing device.
Figure 5 is a schematic plan view illustrating a magneto-optical disk.
Figure 6 is an enlarged plan view illustrating the magneto-optical disk.
Figure 7 is a block diagram of the information recording and reproducing device when recording information from an external device.
Figure 8(a) is an explanatory view illustrating the allocation of image and voice information concerned with the information recording and reproducing device.
Figure 8(b) is an explanatory view illustrating the allocation of the information when music information is rewritten.
Figure 9 is an explanatory view illustrating block and sector structures when recording image information.
Figure 10 is a time chart illustrating the flow of information when recording image information.
Figure 11 is an explanatory view illustrating other block and sector structures when recording image information.
Figure 12 is an explanatory view illustrating the block and sector structures when recording voice information.
Figure 13 is a schematic view illustrating an area allocation of the magneto-optical disk.
Figure 14 is a typical depiction of the relationship between physical sector numbers, block numbers and track numbers.
Figure 15 is a block diagram of another information recording and reproducing device.
Figure 16 is a time chart of a case where recording operations and reproduction operations for verification are repeatedly performed by the block unit.
Figure 17 to Figure 22 show conventional examples.

2038~83 Figure 17 is a schematic plan view of a compact disk.
Figure 18 is a typical depiction of a frame signal format of the compact disk.
Figure 19 is a typical depiction of a sector format of the compact 5 disk.
Figure 20 and Figure 21 are explanatory views respectively of an allocation of image information and voice information in a conventional electronic still camera.
Figure 22 is a time chart of a case where recording operations and 10 reproducing operations for verification are repeatedly performed by the block unit.
Referring to Figure 1 to Figure 6, one embodiment of the present invention is described below.
As shown in Figure 5, a rewritable magneto-optical disk 1 as a 15 recordable recording medium is provided with a TOC area 1a located in the vicinity of the inner edge of the magneto-optical disk 1, and an information recording area 1b occupying most areas outside the TOC area 1a. In the information recording area 1 b, various types of information such as music, textand image information and coded data are recorded, while in the TOC area 1a, 20 additional information relating to the respective information recorded in theinformation recording area 1b, for example the positions of the first and last sectors of the respective information, is recorded.
As shown in Figure 6, on the TOC area 1a and the information recording area 1b of the magneto-optical disk 1, guiding grooves 2 in the form 25 of a spiral (shown by hatching for convenience sake) are formed beforehand, leaving a predetermined space between the grooves in a radial direction of the disk. Absolute addresses (addresses) are recorded on the magneto-optical disk 1 by deviating the guiding grooves 2 outward or inward in the radial direction of the disk according to "0" or "1" (binary logic) of the respective bits 30 of the absolute addresses having gone through a bi-phase mark modulation process. The absolute addresses indicate locations on the disk and are used -Ai ~

- 203~83 as rotation control information in operations such as CLV control. Since the absolute addresses of the present embodiment are equivalent to sectors in the CD format, they are referred to as physical sector numbers hereinafter.
An information recording and reproducing device of the present 5 invention, shown in the block diagram of Figure 4, comprises a spindle motor 3 for supporting and rotating the magneto-optical disk 1, an optical head 4 for irradiating laser light on the magneto-optical disk 1 during recording and reproduction, and a coil 5 for applying a magnetic field onto the magneto-optical disk 1 during recording. As will be described later, recording means composed 10 of the optical head 4 and the coil 5 performs recording operations in its first mode or second mode, based on the control of a controller 13.
The information recording and reproducing device of the present embodiment is configured so as to perform recording operations in the so-called magnetic field modulation method and overwriting operations for recording new 15 information over formerly-recorded information (erasing operations are not required). The information recording and reproducing device has a terminal 6 to which instructions to perform recording/reproducing operations are input froma host device (not shown), such as a so-called personal computer, and data such as text and image information is input from the host device; data may also 20 be transmitted to the host device from terminal 6. When recording information, the information from the host device is sent through the terminal 6 to a switching circuit 19 from an interface 18 as digital data f.
Into the switching circuit 19 are input the digital data f from the interface 18 and additional date e from a sector data generation circuit 20. The25 controller 13 gives instructions to perform a switching operation to the switching circuit 19 upon receiving instructions to record information from the host device through the terminal 6 and the interface 18. In response to the instructions, the switching circuit 19 selects either the data e or data f and sends it to the recorded signal processing circuit 7 as digital data h.

`- 20~858~

The host device is a device which can give instructions to execute recording and reproducing operations or other operations to the present recording and reproducing device.
In the recorded signal processing circuit 7, error detection and 5 correction parity is generated, and the parity and sub-code information from asub-code generation circuit 17 are added to the digital data h Next, the digitaldata h is modulated based on the EFM process. Then a frame synchronization signal is added thereto, and the resulting signal is supplied to a coil driver 8.
The coil driver 8 drives the coil 5 according to the supplied signal, and 10 simultaneously the optical head 4 irradiates laser light on the magneto-optical disk 1 so as to record the signal. Regarding the format of the signal, for example, the signal format shown in Figure 18 and Figure 19 as a conventional example may be used.
In the meantime, in a reproduction operation, a signal reproduced 15 by the optical head 4 is amplified by a reproduction amplifier 10 and is then sent to a prerecorded information detection circuit 11 and a reproduced signal processing circuit 15. The prerecorded signal detection circuit 11 is composed, for example, of a band-pass filter and a PLL (Phase-Locked Loop). A clock signal in synchronization with prerecorded information extracted from the 20 reproduced signal by the band-pass filter is generated by the PLL. A clock signal in synchronization with the prerecorded information composed of the bi-phase mark modulated signal of an absolute address is supplied to a CLV
control circuit 9.
The CLV control circuit 9 compares the frequency of the above 25 synchronous clock from the prerecorded information detection circuit 11 with the reference frequency generated therein, and the resulting differential signal controls the rotation of the spindle motor 3, realizing the accurate CLV control.
The prerecorded information extracted from the reproduced signal by the prerecorded signal information detection circuit 11 is supplied to an address 30 detection circuit 12.

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~3858~

The address detection circuit 12 comprises, for example, a bi-phase mark demodulation circuit and an address decoder. The prerecorded information extracted by the prerecorded information detection circuit 11 is demodulated by the bi-phase mark demodulation circuit, and decoded into an address on the disk, i.e. into a physical sector number, by the address decoder,and then the physical sector number is supplied to the controller 13.
The magneto-optical signal component of the reproduced signal supplied from the reproduction amplifier 10 goes through an EFM demodulation process in the reproduced signal processing circuit 15, and then goes through 10 an error detection and correction process using error detection and correction parity. Then~ signal data having gone through a reproduction process is output to the host device from the terminal 6 through the interface 18.
After going through the EFM demodulation process in the reproduced signal processing circuit 15, the sub-code information is supplied toa sub-code detection circuit 16. The sub-code information recognized by the sub-code detection circuit 16 is sent to the controller 13. The controller 13 receives instructions to perform recording/reproducing operations from the host device through the terminal 6 and the interface 18. The controller 13 has an access function; it recognizes the position of the optical head 4 on the magneto-optical disk 1 and moves the optical head 4 and the coil 5 to a target positionby the use of a shifting means (not shown) on receiving the physical sector number from the address detection circuit 12.
Further, by means of the controller 13, the sub-code information released from the sub-code detection circuit 16 is picked out and recorded in the TOC memory 14, information related to the contents of the TOC and released from the host device through the interface 18 are recorded in the TOC
memory 14, or the contents of the TOC memory 14 are read out.
The sub-code information stored in the TOC memory 14 is supplied to the sub-code generation circuit 17 where sub-codes are generated 30 as needed. The sub-codes go through the EFM process in the recorded signal processing circuit 7 and are then supplied to the coil driver 8. With the above A-- 2`038583 process, the sub-code information in the TOC memory 14 is recorded in the TOC area 1a of the magneto-optical disk 1.
Figure 1 (a) is a typical depiction showing an information allocation in a case where low-volume information da, i.e. a comparatively low volume of information, for example, text information or management information such as a directory, appropriate to performing recording and reproducing operations by the block unit, is recorded on the magneto-optical disk 1 in the first mode of the present invention. I of Figure 1(a) shows the block structure and 11 shows the sector structure of each block. As shown by I of the figure, block numbers BO, B1, B2... are given to the respective blocks, and as shown by 11 of the figure physical sector numbers are given to each sector belonging to the block. The physical sector numbers are indicated as a function of time "minute": "second"
: "a sector number in one second" ( a value from 0 to 74 as there are 75 sectorsin one second in this embodiment). Data dg of each block is composed of eight sectors, for example physical sector number (01: 00: 00) is given to the first sector of block No. B0.
When recording information, in response to instructions to record information in a specified range of blocks given by the host device through the interface 18, the controller 13 calculates physical sector numbers correspondingto the range of blocks. Referring to Figure 1(a), the above operation is explained more precisely below.
For example, when the host device gives instructions to record information in blocks No. B1 to No. B3, the number of sectors per block is determined "eight sectors" and the first physical sector number of block No. B0 is determined (01: 00: 00) beforehand as described above. Therefore, the first physical sector number of block No. B0 where the recording operation starts is given by the equation:

(01: 00: 00) + block No. (1) x the number of sectors (8) = (01: 00: 08) Thus, the first physical sector number of block No. B1 can be easily obtained by the calculation.
Once the physical sector numbers of block No. B1 are obtained, operations such as access to corresponding blocks are performed. For instance, the following operation is performed to block No. B1 shown in Figure 2(a), i.e. additional data e (shown in Figure 2(b)) and digital data f are consecutively switched by the switching circuit 19, which allows desired information to be recorded. The additional data e is composed of n1 pieces of data (here, front additional data d1 to be recorded in two front additional sectors shown in Figure 2(d)) given by the sector data generation circuit 20 and n2 pieces of data (here, rear additional data d2 to be recorded in two rear additional sectors). The digital data f is composed of divided data D1 (shown in Figure 2(c)) which is obtained by dividing low-volume information da such as text information given from the host device through the interface 18 by the sizeof four sectors corresponding to effective sectors dd (Figure 1(a)).
The following explains again the process of recording information in block No. B1.
First, front additional data d1 to be recorded in two sectors, sector No. (01: 00: 08) and the following sector, is given by the sector data generation circuit 20 and is supplied to the recorded signal processing circuit 7 through the switching circuit 19, and is then recorded in the information recording area 1b of the magneto-optical disk 1 (see period t1 in Figure 2).
Next, physical sector No. (01: 00: 10) and the following three sectors which are equivalent to the size of the effective sectors dd are provided for the divided data D1 of the low-volume information da such as text information given from the host device through the interface 18, and the data issupplied to the recorded signal processing circuit 7 through the switching circuit 19 and is then recorded (see period t2 in Figure 2).
Then, rear additional data d2 corresponding to two sectors, i.e.
physical sector No. (01: 00: 14) and the following sector, are given from the sector data generation circuit 20, and the data is supplied to the recorded signal I y. ~

processing circuit 7 through the switching circuit 19 and are then recorded (seeperiod t3 of Figure 2).
In the above process, a recording operation to one block is completed and thereafter data is successively recorded in blocks No. B2 and No. B3 through the respective process shown in periods t4 to t9 of Figure 2 As described above, by only specifying a block number, the host device such as a personal computer directs the information recording and reproducing device to perform the recording operation of the low-volume information da by adding the additional data e. Besides, information recorded in blocks can be rewritten respectively by the block unit.
For the area management of the recorded low-volume information da, the host device may allocate predetermined numbers of the blocks for the area management information as the low-volume information da, and the information may be recorded in the same process as above. The data may also be recorded in the blocks after going through the following process i) going through the controller 13 and the TOC memory 14; ii) being converted into a predetermined format in the sub-code generation circuit 17; and iii) being supplied to the recorded signal processing circuit 7. In the latter process, thearea management information is normally recorded in the TOC area 1a.
Next, referring to Figure 1(b), a process for recording information db whose volume is normally quite high, such as still image information in the second mode of the present invention, will be discussed. I in Figure 1 (b) showsthe block structure, 11 the sector structure, and data ~ in a single block is composed of eight sectors like the above case. 111 shows the high-volume information db to be recorded.
The controller 13 first, in response to instructions to record information in specified blocks given by the host device through the interface 18, converts the block numbers into actual physical sector numbers. The following explains the operation more concretely by referring to Figure 1(b).
For example, when the host device gives instructions to record information in beginning block No. B5625, since it is determined in advance that the number of sector per block is eight sectors and the physical sector number of the first sector of block No. B0 is (01: 00: 00), the physical sector number of the first sector of block No. 5625 is given by the following equation.
(01: 00: 00) + block No. (5625) x the number of sector (8) = (01: 00: 00) + 45000 = (11: 00: 00) Thus, the physical sector number of the first sector of block No. B5625 can be easily given by the calculation.
After performing a necessary access operation to physical sector No. (11: 00: 00) thus obtained (shown in Figure 3(a)), the switching circuit 19 is switched to the sector data generation circuit 20 side (see Figure 3(b)) and additional data _ supplied from the sector data generation circuit 20 is sent tothe recorded signal processing circuit 7 as digital data h. With the operation, front additional data d1 (shown in Figure 3(d)) is recorded in the first two sectors of block No. B5625 (see period t1 of Figure 3).
Next, the switching circuit 19 is switched to the interface 18 side, and then the host device sends high-volume information db supplied as digital data f to the recorded signal processing circuit 7 as digital data h through theterminal 6 and the interface 18. With the operation, the high-volume informationdb (Figure 3(c)) such as still image information is recorded in the rest of the sectors of block No. B5625 (see period t2 of Figure 3).
Then, the high-volume information db is successively recorded in block No. B5626 and the following blocks (see period t3 of Figure 3), and the recording is continued, for example to block No. B6895 depending on the data length (see period t4 of Figure 3).
When the recording of the high-volume information db is completed, the switching circuit 19 is switched to the sector data generation circuit 20 side, and then for example, rear additional data d2 is recorded in the last two sectors of block No. B6895 (see period t5 of Figure 3). In this case, since the recording of the high-volume information db is completed at the sixth sector of the last block, the rear additional data d2 is recorded in the last two sectors of the block. Even when the recording of the high-volume information .

da is completed at the fifth sector of the block or before, no problem occurs ifthe rear additional data d2 is recorded right after the data da.
Upon receiving instructions from the host device, the controller 13 sends the instructions to the sub-code generation circuit 17 through the TOC
5 memory 14. In the sub-code generation circuit 17, input data is converted intoa predetermined format and is supplied to the recorded signal processing circuit7, and is then recorded as area management information. Based on the area management information, the area management of the high-volume information db recorded in the above-mentioned way is achieved. In this case, the area 10 management information is recorded in the TOC area 1a.
The reproduction of the low-volume information da and the high-volume information db thus recorded are performed through the following process. i) The host device sends instructions to perform the reproducing operation and the block numbers of areas to be reproduced to the controller 13 15 through the interface 18. ii) The block numbers are converted into physical sector numbers like the recording process. iii) The reproduction is executed by performing necessary access operations.
If information to be reproduced is the low-volume information da, according to Figure 1(a), a signal reproduced by the optical head 4 is amplified20 by the reproduction amplifier 10, and the magneto-optical component of the reproduced signal goes through an EFM modulation process in the reproduced signal processing circuit 15, and then through an error detection and correctionprocess using error detection and correction parity. In the error detection and correction process, the reproduction of effective sectors dd is performed by 25 using additional data e composed of front additional data d1 recorded in the front additional sectors and rear additional data d2 recorded in the rear additional sectors of Figure 1(a). Only divided data D1, D2 ... of signal data reproduced, which were respectively recorded in four sectors corresponding to the effective sectors dd, are sent to the host device by the block unit through 30 the interface 18.

r-~

If information to be reproduced is high-volume information db, according to Figure 1(b), a signal read by the optical head 4 is amplified by the reproduction amplifier 10, the magneto-optical signal component of the reproduced signal goes through the EFM process in the reproduced signal 5 processing circuit 15, and goes through the error detection and correction process using error detection and correction parity, and is then sent to the host device through the interface 18 and the terminal 6. In this case, since additional front data d1 and additional rear data d2 are respectively added before and after the high-volume information db, even if errors occur in the leading and ending 10 parts of the high-volume information db, the detection and correction can be performed accurately.
As described above, when recording the comparatively low-volume information da, since the information is recorded in the first mode, i.e. by adding front additional data d1 and rear additional data d2 to every block, the 15 information can be rewritten by the block unit, thereby permitting easier management of the information.
Moreover, in this case, the low-volume information da can be recorded in a single block or a small number of blocks. Therefore, even if frontadditional data d1 and rear additional data d2 are added to the respective 20 blocks, a decrease in the utility factor of the recording area of the magneto-optical disk 1 does not cause a serious problem, and a good transfer ratio of data is obtained.
In the meantime, when recording the comparatively high-volume information db, since the information is recorded in the second mode, i.e. by 25 adding front additional data d1 and rear additional data d2 only to the first and last blocks, the utility factor of the magneto-optical disk 1 and the transfer ratio of data can improve. In this case, if the data length of the respective high-volume information db is fixed and if new high-volume information db is rewritten during a rewriting operation into blocks wherein other high-volume information 30 db used to be recorded, the address management is easily maintained during the rewriting operation. Thus, the second mode is appropriate for the high-`- 2038~83 volume information db, whose data length is fixed. Information having different data length may also be recorded in the first mode even if it represents a comparatively high volume of information.
When recording information in the magneto-optical disk 1 so as to create a backup copy of the information which is to be recorded in another recording medium by the use of the present information recording and reproducing device, the frequency of rewriting the information is low as it is abackup copy. Therefore, it is desirable to record the information in the magneto-optical disk 1 in the second mode, permitting a higher utility factor ofthe recording area.
Before starting the recording of information in the magneto-optical disk 1, the host device gives data, such as areas to be used in the first mode and in the second mode respectively and the number of sectors per block, and the data can be registered in a predetermined area of the magneto-optical disk 1. Instead of allocating areas on the magneto-optical disk 1 for each mode separately, by giving identification codes to the information to distinguish therespective modes used, the information recorded in the first mode and the information recorded in the second mode can be mixed on the magneto-optical disk 1.
In this embodiment a single block was composed of eight sectors, however the numerical value was just taken for convenience' sake. Therefore, the size of the block can be changed as needed.
For absolute addresses, if they are prerecorded and distinguishable, they can be recorded in any form, for example in the form of pits.
In the above embodiment a disc-shaped recording medium of magneto-optical type was used; however, a write-once recording medium which allows one writing action and, needless to say, rewritable recording media of other types can be used. Regarding the write-once recording medium, for example, TeOx, TeC, and an organic pigment film are listed. The shape of the recording medium is not limited to a disc as described in the above -embodiment, so tape-type and card-type recording media can also be used if they do not depart from the scope of the present invention.
As described above, the information recording and reproducing device of the present invention comprises recording means for performing 5 information recording operations either in the first mode or the second mode.
In the first mode, one block is composed of (n + n1 + n2) number of sectors which are formed by providing n1 number of front additional sectors in front of each n number of effective sectors and n2 number of rear additional sectors behind thereof, and the information recording operation to be recorded is 10 performed by the block unit. More precisely, the information is divided by the n number of effective sector units, and the information is recorded in the effective sectors of each block by generating and adding front additional data and rear additional data to the respective front and rear additional sectors. Inthe second mode, the information is successively recorded over blocks which 15 are respectively formed of (n + n1 + n2) number of sectors by adding front additional data only to the n1 number of front sectors of the first block and adding rear additional data only to the n2 number of rear sectors of the last block.
Therefore, if the volume of information to be recorded is quite low 20 such as text information, the information can be recorded within a single sector or just a small number of sectors by performing the recording operation in the first mode. Especially when the information is recorded in a rewritable-type recording medium, it is possible to rewrite it easily by the block unit. In thiscase, reproduction errors can be detected and corrected by adding front 25 additional data and rear additional data to each block, and a decrease in theutility factor of the rewritable-type recording medium caused by the addition ofthe additional data to the blocks is not a serious problem since the data volumeis comparatively low.
If, on the contrary, the volume of a data to be recorded is high, i.e.
30 the data is recorded in a number of blocks, by adding predetermined numbers of the front additional data and rear additional data only to the first and last 2038~i83 blocks, specified information is successively recorded in other blocks due to the recording operation in the second mode. This thereby permits the utility factor of the recordable-type recording medium to improve when recording high-volume data. In this case, the additional data is not recorded in blocks other than the first and last blocks. However, since the connection for error correction is successively given between the respective blocks by the non-complete interleaving method, reproduction errors are precisely detected and corrected.
The second mode is especially appropriate for data whose volume is comparatively high and whose data length is fixed, such as still image data.
In particular, when high-volume data whose data length is fixed is recorded on a rewritable-type recording medium in the second mode, by writing new information into a group of blocks, wherein the former data such as still image data is recorded by replacing the formerly-recorded data during the rewriting operation, address management can be carried out easily during such rewriting.
Data whose volume is quite high and whose data length is not fixed can be recorded in the first mode.
The following explains an information recording and reproducing device for recording and reproducing external information (discrete information or successive information).
For members having the same functions as the members in the above embodiment, the same reference numbers are used, and detailed explanations are omitted here.
As shown in Figure 7, an information recording and reproducing device of this embodiment is configured so as to perform recording operations in the so-called magnetic field modulation method, and to perform overwriting operations for recording new information over formerly-recorded information (erasing operations are unnecessary).
The information recording and reproducing device of this embodiment, comprises an input terminal 22 to which analog signals of, for example, musical information to be recorded is input from an external audio device, and also comprises an analog/digital (A/D) converter 21 for converting ~"
,~, analog signals into digital signals. The information recording and reproducing device also comprises a digital/analog (D/A) converter 23 for converting reproduced signals which are digital signals into analog signals and an output terminal 24. The presence of the foregoing members is the only difference 5 between this embodiment and the previous embodiment (see Figure 4).
The information recording and reproducing device receives instructions to perform recording and reproducing operations from a host device such as a personal computer. Data such as text and image information are inpuVoutput between the information recording/reproducing device and the host 10 device through a terminal 6. Data and analog signals of, for example, musicalinformation to be recorded is input to the information recording and reproducingdevice from an external audio device through the input terminal 22.
For example, when recording successive information db such as musical information, analog signals entered from the input terminal 22 are 15 converted into digital data ~ by the A/D converter 21 and then sent to a switching circuit 19. The data is supplied to a recorded signal processing circuit 7 as digital data h, and then goes through the same recording process as in the above embodiment.
On the other hand, when recording discrete information da such 20 as text information, the discrete information da entered from the host devicethrough the terminal 6 is supplied to the switching circuit 19 as digital data fthrough the interface 18, and digital data h, to which additional data _ is appropriately added from the sector data generation circuit 20, is supplied to the recorded signal processing circuit 7. Then the recording process is executed 25 in the same way as in the above embodiment.
The discrete information or successive information recorded in the above manner is reproduced by an optical head 4 and amplified by a reproduction amplifier 10, and is then sent to a prerecorded signal detection circuit 11 and a reproduced signal processing circuit 15. Then the reproduction 30 process is executed in the same way as in the above embodiment. When signal data reproduced is musical information or the like, the signal data is *.~

output to an external audio device or the like as analog musical information through the D/A converter 23 and the output terminal 24.
When recording discrete information such as text information in a magneto-optical disk 1 by the use of the information recording and reproducing device of the present invention, a controller 13, in response to instructions torecord the information in a predetermined range of blocks given by the host device through the interface 18, calculates actual physical sector numbers corresponding to the range of blocks as in the above embodiment.
When the physical sector numbers corresponding to the range of blocks are calculated, access operations to the target blocks are performed.
Desired information is recorded in the blocks by switching additional data e, composed of front additional data d1 and rear additional data d2 given by the sector data generation circuit 20, and digital data f composed of divided data which are obtained by dividing the discrete information da given from the host device through the interface 18 by the number of sectors corresponding to the number of effective sectors (see Figure 2).
Into the switching circuit 19 are input the digital data ~ from the A/D converter 21, the discrete digital data f from the interface 18, and the additional data e from the sector data generation circuit 20. The controller 13 gives instructions to perform a switching operation to the switching circuit 19 upon receiving instructions to record musical information, computer data or the like from the host device through the terminal 6 and the interface 18. In response to the instructions, the switching circuit 19 selects one of the data e, data f and data ~, and sends it as digital data h.
In the meantime, regarding successive information db, such as musical information, access operations to the physical sector numbers thus obtained are performed. Musical information, in the form of analog signals from the input terminal 22, is converted into digital data q by the A/D converter 21,and is then supplied to the recorded signal processing circuit 7 through the switching circuit 19. By this process, desired musical information is successively recorded in, for example, physical sector number (11: 00: 00), ..

2038~83 corresponding to the first sector of block No. B5625, and the following sector numbers (see Figure 1(c)).
When the host device gives instructions to end the recording operation to the controller 13 through the terminal 6 and the interface 18, the recording of the musical information is ended. According to Figure 1(c), the recording of the musical information is finished at block No. B6895.
For area management of the successive information db thus recorded, the area management information goes through the controller 13 and the TOC memory 14 and is converted into a predetermined format by a sub-code generation circuit 17. Then, it is supplied to the recorded signal processing circuit 7 and recorded. In this case, the area management information is recorded in the TOC area 1a serving as a recording area.
The reproduction of the thus-recorded discrete information da and the successive information db is performed through the following process. First,the host device sends instructions to execute the reproducing operation, and theblock numbers of areas to be reproduced, to the controller 13 through the interface 18. Next, the block numbers are converted into physical sector numbers in the same manner as above. Then necessary access operations are performed.
When information to be reproduced is the discrete information da, according to Figure 1(a), reproduced signals from the optical head 4 are amplified by the reproduction amplifier 10, and the magneto-optical component of the reproduced signals goes through the EFM process in the reproduced signal processing circuit 15 and goes through an error detection and correction process using error detection and correction parity. In the error detection and correction process, the reproduction of effective sectors dd is executed by using additional data e composed of front additional data d1 recorded in the front additional sectors and rear additional data d2 recorded in the rear additional sectors of Figure 1(a). Only divided data D1, D2 ... of the reproduced signal 30 data, which were recorded in four sectors corresponding to the effective sectors dd, are sent to the host device through the interface 18 in each block.

When information to be reproduced is the successive information db, according to Figure 1(c), reproduced signals from the optical head 4 are amplified by the reproduction amplifier 10. The magneto-optical component of the reproduced signals goes through the EFM process in the reproduced signal processing circuit 15, then goes through the error detection and correction process using error detection and correction parity, and is then released as, for instance, analog musical information through the D/A converter 23 and the output terminal 24.
Accordingly, it is possible to provide an information recording and reproducing device that uses the non-complete interleaving method, is capable of recording various types of discrete information da which can be rewritten by specifying block numbers, and is capable of recording and reproducing successive information db such as musical information.
When recording the discrete information da together with the successive information db in a single magneto-optical disk 1 but in different formats, both types of information may be randomly mixed on the disk by providing identification codes to them to distinguish them from each other, or separate recording areas for each type of information may be arranged beforehand.
In this embodiment, a single block was composed of eight sectors;
however, that value was taken for only convenience' sake. The size of the block can be varied as needed.
For absolute addresses, if they are prerecorded and distinguishable, they can be recorded in any form, for example, in the form of pits.
Further, in the above embodiment a disc-shaped recording medium of magneto-optical type was used; however, a write-once type recording medium, which allows a single writing action and, needless to say, rewritable recording media of other types can be used. Regarding the write-once recording medium, for example TeOx, TeC, and an organic pigment film are listed. The shape of the recording medium is not limited to a disc as was 2Q38~83 described in the above embodiment, so tape-type and card-type recording media can also be used if they do not depart from the scope of the present invention.
As described above, the information recording and reproducing 5 device of the present embodiment firstly comprises a calculating means for calculating physical sector numbers according to the block number of a block whereto recording and reproducing operations are performed by the block unit.
The block is composed of a predetermined n number of effective sectors, n, number of front dummy sectors provided in front of the effective sectors and n2 10 number of rear dummy sectors provided behind. The device also comprises a recording means for recording information in the physical sectors obtained by the calculating means by dividing the information by the n number of effective sector units, and by generating and adding front additional data and rear additional data to the respective front and rear additional sectors when the 15 information is discrete information. The recording means also records information successively in the physical sectors obtained by the calculating means when the information is successive information.
Accordingly, the host device connected to the present information recording and reproducing device can direct the information recording and 20 reproducing device to record and reproduce discrete information such as text information and coded data by only specifying block numbers whereto recording and reproducing operations are performed, and need not provide the additional sectors which are required for recording and reproduction operations using the non-complete interleaving method. Moreover, the host device can give 25 instructions to perform a recording and reproducing operation by the block unit, and can handle the information management easily as there is no need for adding data relating to additional sectors nor transferring the data.
Especially if data is recorded in a rewritable-type recording medium, it is possible to rewrite the recorded data partly when the host device 30 gives instructions to execute rewriting operation by the block unit.

~' 2038~83 Further according to the present invention, since successive information such as musical information requiring the non-complete interleaving method can be mixed with discrete information and recorded on the same disk, various types of information can be recorded and reproduced in a single 5 recording medium. Besides, since various types of information can be recorded in one type of rewritable recording media, different types of recording media are not required when recording each type of information, resulting in a decrease in the price of the recording media.
The following explains an information recording and reproducing 10 device of the present invention built into an electric still camera which is capable of recording voice information. For members whose functions are the same as the members of the above embodiments, the same reference numbers are used here, and the detailed explanations thereof are omitted here.
An information recording and reproducing device described here 15 is also configured so as to perform recording operations in the so-called magnetic field modulation method, and to perform overwriting operations for recording new information over formerly-recorded information.
In order to record image information, as shown in Figure 4 the information recording and reproducing device comprises: an input terminal 6a 20 to which image information is input from an image pickup element (not shown),an input terminal 6b to which voice information is input from a microphone (not shown), output terminals 6c, 6d from which image information and voice information are respectively released, and a terminal 6e. Control signals are inpuVoutput between the information recording and reproducing device and a 25 host controller for controlling the respective parts of the electronic still camera, such as the image pickup element and the microphone, through the terminal 6e.
When recording image (still image) information, image information input to an interface 18 from the input terminal 6a is sent to a switching circuit 19 as digital data f. In the switching circuit 19, the digital data f and additional 30 data _ (described later) from a sector data generation circuit 20 are switched, and then digital data h which is formed by adding the additional data e to the digital data f is supplied to a recorded signal processing circuit 7.
In the meantime, when recording voice information, voice information input through the input terminal 6b is supplied to the switching circuit 5 19 through the interface 18 as digital data f In this case, additional data e from the sector data generation circuit 20 is not added thereto, and therefore the digital data f, as it is, is supplied to the recorded signal processing circuit 7 as digital data h and is then recorded in the same manner as described above.
Image information or voice information reproduced by an optical 10 head 4 is amplified by a reproduction amplifier 10, is sent to a prerecorded information detection circuit 11 and a reproduced signal processing circuit 15, and is then reproduced in the same manner as described above.
The reproduced image and voice information are output to a display means and a voice output means (not shown) of a television set or like 15 device through the interface 18 and the output terminals 6c, 6d.
A controller 13 for recording and reproducing information receives instructions to record or reproduce information from the host controller throughthe terminal 6e and the interface 18.
As shown in Figure 8(a), a single block is composed, for example, 20 of eight sectors, and information is recorded or reproduced in the information recording area 1b of a magneto-optical disk 1 by the block unit. Numbers B0, B1 ... are given to each block in order, i.e. smaller numbers are given to blocks located at inner parts of the magneto-optical disk 1 and larger block numbers are given to blocks located at outer parts thereof (see Figure 12).
In this embodiment, image information recording areas 11, 12 (shown by hatching for convenience' sake in Figure 8), wherein image information whose data volume is fixed is recorded, are allocated in order from the outer edge of the information recording area 1b, i.e. from the largest blocknumber. Voice information recording areas A1, A2 ..., wherein voice information 30 whose data volume varies is recorded, are allocated in order from the inner edge of the information recording area 1b, i.e. from the smallest block number.

,~

In the information recording areas 11,12 ..., image information is recorded fromthe smallest block number toward the larger block numbers.
According to the above information allocation, since blank areas are only presented in a location between the image information recording areas 11, 12 .. and the voice information recording area A1, A2 .. , wherein no information is recorded, the utility factor of the information recording area 1 b can improve.
- In case of rewriting recorded information, as shown in Figure 8(b), voice information relating to all the recorded image information can be rewritten 10 en bloc. In the figure A1', A2' ... represent the respective voice information recording areas after having been rewritten.
In case recorded voice information is unnecessary, a group of voice information successively recorded can easily be erased, and successive blank areas created by the erasing operation can be used for recording image 15 information.
Next, referring to Figure 9 the following explains address control to be performed when the present information recording and reproducing device records image information in the magneto-optical disk 1. 1 of the figure shows the block structure in the information recording area 1b, and 11 the sector 20 structure of each block. As shown in I of the figure, each block is provided with a block number such as B22500, B22501 ... B22563 ..., while as shown in 11 of the figure each sector of the blocks is provided with a physical sector number indicated as a function of time: "minute": "second": a sector number in one second (a value from 00 to 74 as there are 75 sectors in one second in this 25 embodiment). Data dg in each block is composed of eight sectors. Block No.
B0 (see Figure 12) is given to a block located in the innermost part of the information recording area 1b, and for example, physical sector No. ((01: 00 : 00) is given to the first sector of the block.
When recording image information, the controller 13 for recording 30 and reproduction, in response to instructions to record the information in a specified range of blocks given from the host controller through the interface 18, 2038~i83 calculates actual physical sector numbers corresponding to the blocks.
Referring to Figure 9, the following explains the operation more precisely.
For example, in case the host controller specifies block N o.
B22500 to block N o. B22563 as information recording area 11 to record image 5 information da1 of a first image, since the number of sectors per block is predetermined as eight sectors and the first physical sector number of block N o.
B0 is predetermined (01: 00: 00), the first physical sector number of block N o.B22500 where the recording operation is commenced can be given by the equation:

(01: 00: 00) + block number (22500) x the number of sectors (8) = (41: 00:
00) Thus, the first physical sector number of block N o. B22500 can easily be obtained. When the physical sector numbers of block N o. B22500 is obtained, access operations to the block are performed.
In this embodiment, a single block is composed of eight sectors, however, in fact the image information da1 is only recorded in the middle four sectors thereof which are effective sectors dd, and front additional data d1 andrear additional data d2 are respectively recorded in the first two sectors and the last two sectors of each block.
When recording and reproducing data recorded in the effective sectors dd based on the non-complete interleaving method called CIRC, if reproduction errors occur in the data recorded in the effective sectors dd, the front additional data d1 and the rear additional data d2, which are dummy data including error detection and correction parity, detect and correct the errors. By adding the front additional data d1 and rear additional data d2 to each block, even if information is rewritten by the block unit, data stored in the effectivesectors dd of the respective blocks can be reproduced accurately.
As described above, after calculating the first physical sector number of block N o. B22500 (see Figure 10(a)) and performing the access 2o38583 operation thereto, the switching circuit 19 switches additional data e (see Figure 10(b)) and digital data f consecutively so as to record desired information. Theadditional data e is composed of the front additional data d1 (see Figure 10(d))and the rear additional data d2 given from the sector data generation circuit 20, 5 and the digital data f is composed of divided data D1 which is the first data obtained by dividing the image information da1 of the first image provided through the interface 18 by four sectors corresponding to the effective sectors dd.
The following explains again the process of recording information 10in block No. B22500. First, the front additional data d1 to be recorded in physical sector No. (41: 00: 00) and the following sector is given by the sectordata generation circuit 20, and is supplied to the recorded signal processing circuit 7 through the switching circuit 19, and is then recorded in the information recording area 1b of the magneto-optical disk 1 (see period t1 of Figure 10).
15Next, physical sector No. (41: 00: 02) and the following three sectors which are equivalent to the size of the effective sectors dd are provided as a group of sectors for the divided data D1 of the image information da1 giventhrough the interface 18, and the data is supplied to the recorded signal processing circuit 7 through the switching circuit 19 and is then recorded therein 20 (see period t2 of Figure 10).
Then, the rear additional data d2 corresponding to two sectors, i.e.
physical sector No. (41: 00: 06) and the following sector is given from the sector data generation circuit 20, and is supplied to the recorded signal processing circuit 7 through the switching circuit 19 and is then recorded therein 25 (see period t3 of Figure 10).
In the above process, the recording operation for one block is completed and data is thereafter successively recorded in blocks No. B22501 to No. B22563 through the respective process shown in periods t4 to t9.
When recording image information da2 of a second image, a range 30 of blocks in the image information recording area 12 is arranged such that the last block thereof is located in front of the first block of the image information ~' recording area 11, and the number of blocks of the image information recording area 12 equals that of the information recording area 11. Based on the above arrangement, physical sector numbers are calculated. Regarding image information recording areas 13, 14 ... for information on a third and following 5 images, ranges of blocks are arranged so that the number of blocks for each piece of image is fixed, and the block number of a group of blocks to which information is to be recorded becomes gradually smaller. Based on this arrangement, physical sector numbers are calculated.
For the area management of the recorded image information da1, 10 the host controller may allocate predetermined blocks for the area managementinformation so as to perform the recording operation in the same process as above. The information may also go through the following process (i) pass through the controller 13 and a TOC memory 14; (ii) be converted into a predetermined format by a sub-code generation circuit 17, (iii) be supplied to the 15 recorded signal processing circuit 7; and (iv) be recorded. In the case of the latter process, normally the area management information is recorded in the TOC area 1a.
Instead of giving the front additional data d1 and rear additional data d2 to each block when recording the image information da1, da2 ... as 20 shown in Figure 9, the front additional data d1 may only be given to the first block of a group of blocks and the rear additional data d2 to the last block thereof, and the image information da1, da2 ... may be recorded successively in the rest of the blocks as shown in Figure 11. In this case, for example, the recording of the information da1 of the first image, is completed at block No.
B22532, thereby permitting the utility factor of the information recording area 1 b to improve.
Next, referring to Figure 12 a recording operation of voice information is explained below. I in the figure shows the block structure and 11the second structure, and as described above the data dg of a single block is composed of eight sectors. 111 in the figure shows voice information to be recorded.
A

- 2038~83 The controller 13 for recording and reproduction first, in response to instructions to record information in a specified block and the following blocks given from the host controller through the interface 18, performs operations to convert the block numbers into actual physical sector numbers. Referring to 5 Figure 12, the following explains the operations more precisely.
For example, voice information recording area A1 (see Figure 8(a)), wherein voice information db1 corresponding to the first image is recorded, starts from the smallest block number, i.e. block No. B0 in the information recording area 1b. Since it is predetermined that physical sector No. (01: 00: 00) is given to the first sector of block No. B0, the controller 13for recording and reproduction performs an access operation to the sector.
Then, the voice information db1 entered from the input terminal 6b through the interface 18 is supplied to the recorded signal processing circuit 7as digital data h through the switching circuit 19, so that the information db1 is successively recorded in sector No. (01: 00: 00) and the following sectors. In the case of recording the voice information db1, since all eight sectors of one block are the corresponding sectors, front additional data and rear additional data are not added.
When the host controller gives instructions to end the recording 20 operation to the controller 13 for recording and reproduction through the interface 18, the recording of the voice information db1 is ended. According to a case shown in Figure 12, the recording of the voice information db1 is ended at block No. B74. In this case, succeeding blocks, block No. B75 and the following blocks, are allocated for voice information recording area A2 wherein 25 voice information for the second image is to be recorded. When recording information in the voice information recording area A2, the physical sector number of the first sector of block No. B75 is calculated by the same process as above. Further, the physical sector numbers of the first sectors in voice information recording areas A3, A4 ... for the third and following images can be30 calculated in the same process.

The area management of the recorded voice information db1, db2 ... is achieved in the following way. Upon receiving instructions to perform a recording operation from the host controller, the controller 13 sends the instructions to the sub-code generation circuit 17 through the TOC memory 14.
5 In the sub-code generation circuit 17, input data is converted into a predetermined format and is supplied to the recorded signal processing circuit 7, and is then recorded as area management information. In this case, the area management information is recorded in the TOC area 1a.
When reproducing the image information da1, da2 ... or the voice 10 information db1, db2 ... thus recorded, the host controller gives instructions to perform a reproducing operation and the block numbers of areas to be reproduced to the controller 13 for recording and reproduction through the interface 18. Then, the controller 13 converts the block numbers into physical sector numbers and performs necessary access operations so as to execute the 15 reproducing operation.
According to Figure 9, when reproducing the image information da1, da2 ..., a reproduced signal from the optical head 4 is amplified by the reproduction amplifier 10, and the magneto-optical component of the reproduced signal goes through the EFM demodulation process in the reproduced signal 20 processing circuit 15 and goes through an error detection and correction process using error detection and correction parity. In the error detection and correction process, the reproduction of effective sectors dd is performed by using the additional data e composed of the front additional data d1 recorded in the front additional sectors of Figure 9, and by using the rear additional data 25 d2 recorded in the rear additional sectors. Only divided data D1, D2 ... of the reproduced signal data, which are recorded in four sectors corresponding to the effective sectors dd, are released at each block through the interface 18 and the output terminal 6c.
According to Figure 12, when reproducing the voice information 30 db1, db2 ..., a reproduced signal from the optical head 4 is amplified by thereproduction amplifier 10, and the magneto-optical component of the signal goes through the EFM demodulation process in the reproduced signal processing circuit 15, goes through an error detection and correction process using error detection and correction parity, and is then released through the interface 18 and the output terminal 6d.
This embodiment was explained by using image information of an electronic still camera as information whose volume is fixed and voice information thereof as information whose volume varies. However, the present invention is also effective in a case where the information whose volume is fixed and the information whose volume varies are mixed and recorded on a single recording medium.
In this embodiment, a single block was composed of eight sectors;
however, that value was just taken for convenience' sake and the size of the block can be changed as needed.
For absolute addresses (physical sector numbers), if they are prerecorded with distinguishable information, they can be recorded in any form, for example in the form of pits.
In this embodiment a disc-shaped recording medium of magneto-optical type was used; however, rewritable recording media of other types can be used, and tape-type and card-type recording media can also be used if they do not depart from the scope of the present invention.
The following explains another embodiment relating to an information recording and reproducing device of the present invention in detail.For members having the same functions as the members of the above embodiments, the same reference numbers are used and the detailed explanations are omitted here.
As shown in Figure 13, a magneto-optical disk 1 of this embodiment whose structure is shown in Figure 5 and Figure 6 is divided into three ring-shaped areas T1 to T3 (units).
In this embodiment, the area T, corresponds to track N o. 1 of the CD format, the area T2 track N o. 2, and the area T3 track N o. 3. As shown in Table 1, track N o. 1 occupies physical sector N o. (01: 23: 00) to physical sector No. (09: 22: 74), track No. 2 physical sector No. (09: 24: 00) to physical sector No. (29: 23: 74), and track No. 3 physical sector No. (29: 25 : 00) to physical sector No. (57: 24: 74). Here, the physical sector number is indicated as successive time information, increasing from the inner edge of the 5 magneto-optical disk 1 outward thereof in order, i.e. (minute: second: frame information). Since the sector length is 13.3 ms, there are 75 sectors in one second, and therefore the frame is indicated by a number from 00 to 74.

TRACK NO. AREA INFORMATION NUMBER OF SECTORS/
BLOCK
START END
POSITIONPOSITION
1 01 :23:0009:22:74 8 2 09:24:0029:23:74 12 3 29:25:0057:24:74 16 Regarding the block size in each track, it is predetermined that a single block in track No. 1 is composed of eight sectors, a single block in track 15 No. 2 is composed of 12 sectors and a single block in track No. 3 is composed of 16 sectors. The data of Table 1 is recorded in a TOC area 1a (unit information recording area), shown in Figure 13, for managemenVformat information of the respective areas. Based on the contents of the TOC area 1 a, the location of information areas on the disk and the size of a block in each 20 area can be recognized.
Figure 14 is a typical depiction of the relationship between physical sector numbers, block numbers and track numbers, and shows that track No.

2038~83 1 corresponds to the physical sectors, No.(01:23:00) to No. (09: 22:74), on the disk. In the area T, of track No. 1, since a single block is composed of eight sectors, block No. 0 corresponds to the physical sectors, No. (01: 23:00) to No. (01: 23:07) and block No. 1 to the physical sectors, No. (01: 23:08) to No. (01: 23:15). As the size of the area T1 of track No. 1 corresponds to the size of physical sector No.(01:23:00) to physical sector No.(09:22:74), that is equivalent to (08:00:00), the number of sectors in the area T, of track No.1is8x60x75=36000 sectors. The number of blocks is 36000/8=
4500 blocks. Therefore, the blocks, No.0 to No.4499, are allocated for track No.1.
Similarly, track No.2 corresponds to the physical sectors, No.(09 :24:00) to No.(29:23:74), on the disk. In the area T2 of track No.2, since a single block is composed of 12 sectors, block No. 0 corresponds to the physical sectors, No.(09:24:00) to No.(09:24:11). The number of sectors in the area T2 of track No.2is20x60x75=90000 sectors. The number of blocks is 90000/12=7500 blocks. Therefore, the blocks, No.0 to No.7499, are allocated for track No. 2.
Further, track No. 3 corresponds to the physical sectors, No. (29 :25:00) to No. (57:24:74), on the disk. In the area T3 of track No. 3, since a single block is composed of 16 sectors, block No. 0 corresponds to the physical sectors, No.(29:25:00) to No.(29:25:15). The number of sectors in the area T3 of track No.3is28x60x75=126000 sectors. The number of blocks is 126000/16=7875 blocks. Therefore, the blocks, No.0 to No. 7874, are allocated for track No. 3. XX of the figure represents border areas between the tracks, and blocks corresponding to the border areas are not numbered.
According to the allocation of information areas wherein a single block in track No.1is composed of eight sectors, a single block in track No.2 is composed of 12 sectors and a single sector in track No.3is composed of 16 sectors, by specifying the respective block numbers data can be recorded or reproduced in the appropriate blocks according to the data volume, so that ,~ , i various types of information including file management information can be stored in appropriate blocks in a single disk.
For example, the information volume of text and similar information is comparatively low since it is coded data, and therefore the information can 5 be recorded and reproduced more efficiently in the area T2 corresponding to track N o. 2. On the contrary, since the information volume of image informationor the like is high, according to the above allocation the information can be recorded more effficiently in the area T3 corresponding to track N o. 3. Further, since the information volume of file management information, such as the 10 directories of various files of track N o. 2 and track N o. 3, is normally low, according to the allocation the file management information can be recorded more efficiently in the area T, corresponding to track N o. 1. Every time a newfile is created and data is added, updated, erased or read out in track N o. 2 or track N o. 3, the file management information in the area T, of track No. 1 is 15 updated. The sizes of the blocks mentioned above are just examples provided to meet the convenience of the explanation, and therefore the sizes can be determined accordingly.
Regarding the file management information, there are directories, a File Allocation Table (FAT) and the like. For example, regarding MS-DOS
(disk operating system of Microsoft Corp.), according to page 35 of "applied MS-DOS" published by Kabushiki Kaisha ASCII in Japan on July 31, 1986, the name, type (command, data, etc.), attribute, updated date, size and first cluster number of a file and the like are recorded in the directory for each file, and cluster numbers used in the respective files are recorded in order in the FAT.
In this embodiment, for example, the track number and block number may be recorded in the directory instead of the first cluster number of a file in MS-DOS, and the block numbers may be recorded in order in the FAT instead of the cluster numbers.
In this embodiment, the explanation was made by referring to a 30 case where the positional information, block size and similar information of the respective information areas are allocated in the TOC area 1a as shown in Figure 13; however, the information can be allocated in different ways if it is recorded in a predetermined area.
For absolute addresses (physical sector numbers), if they are prerecorded and distinguishable information, they can be recorded in any form.
As shown in Figure 15, the controller as a processing section of the information recording and reproducing device of this embodiment performs the following operations in response to instructions given by the host device.
When the disk of the present embodiment has an initialized state (no information is recorded), the unit allocation information ( a unit is a collection of blocks) on the recording medium, sector number information indicating the number of sectors per block and unit number information identifying each unit, which are given from the host device through the interface 18 are transferred to a TOC memory 14 as a unit (ortrack). This corresponds to the data of Table 1.
Immediately after performing an access operation to a location corresponding to the TOC area 1a of the magneto-optical disk 1 by controlling an optical head/coil shifting means (not shown), the data of the TOC memory 14 goes through a predetermined process in a sub-code generation circuit 17 and the recorded signal processing circuit 7, and is then recorded by driving a coil 5 through a coil driver 8. This series of operations may be performed immediately before the disk 1 is discharged from the information recording and reproducing device, instead of being performed when transferring information from the host device.
The recording of information relating to the unit is performed by transferring information from the host device when the disk is initialized, or when adding or changing units.
In the embodiment, information, including unit number information for identifying each unit was recorded in the TOC area 1a; however, the unit number information is unnecessary if the allocation of information relating to the respective units is determined according to absolute addresses in the TOC area 1a.

As described above, when the disk 1 whose TOC area 1 a contains the area information of each track and the number of sectors of each block is loaded, first the data in the TOC area 1a is read. The load action is initiated when the disk 1 is placed into the present information recording and reproducing5 device if it is in an initialized state, or when the recording and reproducingdevice is turned on again if it is turned off with the disk 1 therein. In particular, the controller 13 controls the optical head/coil shifting means (not shown) and moves the optical head 4 to a position on the disk corresponding to the TOC
area 1a so as to perform the reproduction operation.
The information in the TOC area 1a is directed to the reproduced signal processing circuit 15 through the optical head 4 and the reproduction amplifier 10, and the actual TOC information is supplied to the controller 13 from the reproduced signal processing circuit 15 through a sub-code detection circuit16. The TOC information is stored as operational information for the 15 succeeding recording and reproducing operations in the TOC memory 14, and can be sent to the host device through the interface 18. In the succeeding information recording and reproducing operations, in response to a unit number and predetermined blocks of the unit specified by the host device through the interface 18, the controller 13 performs a physical sector address operation by 20 the use of the data of the TOC memory 14.
Referring to Figure 14, the following explains the above operation more precisely.
For example, when the host device gives instructions to record new data in unit No. 2 in a predetermined file name, the file management 25 information recorded in track No. 1 is first read out; then an unused block in track No. 2 is detected. If the block number of the unused block is block No.
1, then since the area of track No. 2 begins at sector No. (09: 24: 00) according to the TOC memory and the block is composed of 12 sectors, the first physical sector address of block No. 1 can easily be obtained from the equation:
(09: 24: 00) + block number (1) x the number of sectors (12) = (09: 24: 12) .

20~8S8~

After performing necessary access operations to the physical sector thus obtained, the recording information is transferred through the interface 18 so as to execute the recording operation of the desired information. Needless to say, in the operation, management information such as the name of the above file 5 is added to an unused block in the directory recording area of track No. 1, and at the same time management information such as the block number where the file is stored is recorded in an unused block of the FAT recording area.
When the host device gives instructions to record information in blocks beginning with block No. 1 of unit No. 1, according to the TOC memory 14, since track No. 1 begins at sector No. (01: 23: 00) and each block is composed of eight sectors, the first physical sector address of block No. 1 can easily be obtained from the equation:

(01: 23: 00) + block number (1) x the number of sectors (8) = (01: 23: 08) 15 Necessary access operations to the physical sector numbers thus obtained are performed, and then recording information is transferred through the interface 18, which allows the desired information to be recorded.
In the embodiment, information relating to the respective units (information on the block sizes of the respective units or the like) was recorded 20 and reproduced in the TOC area 1a of the disk 1; however, the information canbe recorded and reproduced in an area other than the TOC area, if it is a predetermined area. The information relating to the respective units can also be recorded and reproduced in a main data area instead of a sub-code area.
In this case, the controller 13 is connected to the recorded signal processing 25 circuit 7 and the reproduced signal processing circuit 15 as shown by the broken line of Figure 15, and then the recording and reproducing operations of information relating to the respective units are performed.
According to the above arrangement, areas on the disk are composed of different numbers of blocks, and the information capacity of the ~ A~l -,~

respective areas varies so as to correspond to various types of information including the file management information; the file management information of all the files can be managed collectively. As a result, the respective information can be recorded and reproduced easily and efficiently.
In this embodiment a disc-shaped recording medium of magneto-optical type was used; however, rewritable recording media of other types can be used, and recording media of tape, card or other type can also be used if they do not depart from the scope of the present invention.
As described above, the information recording and reproducing device of the present embodiment comprises a processing means which allocates units composed of collections of blocks on the recording medium so that the allocation of information of the respective units on the disk and the sector number information of the respective blocks of each unit are recorded in the predetermined unit information recording area on the recording medium, and manages files by the use of a unit for recording file management information provided separately from a unit for recording files. Therefore, blocks composed of different numbers of sectors can be provided on a single disk. As a result, blocks of the optimum sizes can be allocated for various types of information according to the data length, permitting the recording area of the recording medium to be used efficiently. Moreover, since a unit is provided where the filemanagement information of all the units is to be recorded, the file management information can be recorded in blocks composed of the optimum number of sectors, allowing the utility factor of the recording medium and the average recording and reproducing speed of data to improve. When replacing the recording medium, the recording conditions of the files of each unit can be recognized promptly by reading out just the unit where the file management information is recorded.
Besides, even if the digital information is recorded or reproduced in the area T1 corresponding to tràck No. 1 instead of the area T2 correspondingto track No. 2, the information can be recorded and reproduced efficiently. In this case, image and other information can be recorded in the area T3 corresponding to track No. 3 as the information volume becomes large.
Needless to say, the sizes of the blocks mentioned above are just examples used for ease of explanation, and sizes can be determined accordingly. Figure 16 is a time chart of a case where recording operations and reproducing 5 operations for verification were repeatedly performed by the block unit using the disk of this embodiment.
Absolute address information as prerecorded information is recorded on the above disk based on the Constant Linear Velocity (CLV) method, so that the following recording and reproducing operations must also 10 be performed using the CLV method and the prerecorded absolute address information. The areas T" T2, and T3 are arranged such that the block size in each area is close to (but does not exceed) the number of sectors in one disk rotation.
In Figure 16, the axis of the abscissa shows the elapse of time, (a) 15 and (b) are respective charts for a recording operation and a reproducing operation for verification performed respectively at the inner and outer edges of the disk in the area T, (i.e. track No. 1) of Figure 13, (c) and (d) are respective charts for a recording operation and a reproducing operation for verification performed respectively at the inner and outer edges of the disk in the area T2 20 (i.e. track No. 2), and (e) and (f) are charts for a recording operation and a reproducing operation for verification performed respectively at the inner and outer edges of the disk in the area T3 (i.e. track No. 3). W0 of Figure 16 showsa recording operation performed in block No. 0, and Ro of the figure shows a reproducing operation for verification performed after the recording operation in 25 block No. 0. Subscript characters affixed to the letters W and R indicate block numbers, and as set out above, show a recording operation and a reproducing operation for verification performed in the respective positions on the disk.
Consequently, the time elapsed between the beginning of the recording operation and the beginning of the reproducing operation for verification equals30 the time taken for a single rotation of the disk at the respective information positions. Thus the wait time for the disk rotation to proceed to the reproducing ~--A

operation for verification from the recording operation is given by subtracting the time taken for the recording operation from the above time.
As is clear from Figure 16, since the sizes of blocks become larger from the inside to the outside of the disk in this embodiment, the wait time for5 the disk rotation does not much increase even in outer parts of the disk.
Consequently, recording operations and reproducing operations for verification can effficiently be performed by the block unit based on the CLV method independently of the radial position on the disk.
In this embodiment, the positional information and the block size 10 information of the respective information areas are stored in the TOC area 1a(see Figure 13); however, the information can be recorded in other areas if theyare predetermined.
In the embodiment, to meet the convenience of the explanation, the disk is divided into three areas (units), T" T2, and T3, and the block sizes15 (the number of sectors in one block) in the areas are determined as 8, 12 and16, respectively. However, the block size, the number of areas (unit), and the number of blocks in one area (unit) can be changed if necessary.
In order to improve the average recording and reproducing speed of data, the numbers of sectors are arranged as 8, 12, and 16 as described 20 above, which are close to the numbers of sectors in one disk rotation in the respective areas. In other words, in the case of using a rewritable-type recording medium in the shape of a disc (for example, a magneto-optical disk), a reproduction operation for verification needs to be performed immediately after the completion of the recording, and therefore the way of arranging the block 25 size affects the average recording and reproducing speed of data.
For example, if the controlled linear velocity of the disk based on the CLV method is 1.2 m/s, the allowable number of sectors in each of the innermost tracks in the recording areas T" T2 and T3 is 10.2, 12.2, and 16.2, respectively, according to the calculation. If the block sizes are arranged to be 30 close to the numbers of sectors (positive integral numbers), the wait time for the disk rotation (the time taken between the completion of the recording information in a block and the starting of a reproduction operation for verification after performing a track jump) is shortened. That allows the average recording and reproducing speed of data to improve to a great degree.
If the number of sectors in the block in the area T1 is determined to be, for example, 20 (~ 10.2 x 2) or 30 (< 10.2 x 3), the average recording and reproducing speed of data is achieved to a similar extent as above.
Generally, if the block size is determined so as to correspond to the number of sectors in N-time disk rotations or slightly less, or even if the numbers of areas (units) are increased, similar to the above the average recording and reproducing speed of data can improve.
More precisely, the average speed of recording and reproducing data can improve greatly when the block size Bs is determined so as to satisfy the equation:

((m x n - 0.5 m) ~ Bs < (m x n) where m is the number of sectors in one disk rotation in the innermost part of each unit (number of sector / rotation), and n (a positive integral number) is the number of tracks in one block in the innermost part of each unit.
For absolute addresses, if they are prerecorded and distinguishable information, they can be recorded in any form.
Thus, the recording and reproducing operations of the respective information can be performed efficiently by providing areas, which are composed of blocks having information capacity appropriate for various types of information, on the disk.
In this embodiment a disc-shaped recording medium of magneto-optical type was used; however, a write-once type of recording medium which allows one writing action, as well as various types of rewritable-type recordingmedia, can be used. Regarding the write-once type of recording medium, for example, TeOx, TeC, and an organic pigment film are listed. The shape of the recording medium is not limited to a disc, so tape-type and card-type recording media can also be used if they do not depart from the scope of the present invention.
Especially in the case of applying the present invention to a rewritable-type recording medium, it is possible to erase information by the block 5 unit (for example, by each format), and each unit size (the number of blocks in one unit) can easily be changed, i.e. increasing/decreasing the unit size or block size. Consequently, a recording medium can be efficiently used.
For instance, in case information in the area T2 is unnecessary and more capacity is needed for the area T1, it is possible to increase the capacity10 of the area T, by erasing only information in the area T2 and recording in the area T2 information having the same format as the information in the area T1.
In case information is recorded in a plurality of areas with arbitrary block sizes, it is possible to improve the average speed of recording and reproducing information during rewriting operations thereafter by rearranging the block size15 of each unit such that the block size becomes larger from the inside to the outside of the disk (relocation of information).
As described above, the recording medium relating to the present embodiment is provided with a plurality of units (which are collections of blocks) and a unit information recording area, wherein allocation information of each unit 20 on the recording medium and sector number information indicating the number of sectors in one block in each sector are recorded, thereby permitting various blocks having different numbers of sectors to be provided on a single recording medium. As a result, blocks composed of appropriate numbers of sectors can be allocated for various types of information according to the data length, which 25 allows the recording area of the recording medium to be used efficiently. Thus, the average recording and reproducing speed of data improves. Moreover, since the recording medium of the present invention can cope with various forms of information of different data lengths, if absolute address information is prerecorded only one type of recording media needs to be prepared.
30 Consequently, the recording media can be shared among various types of information and the price can be decreased.
A

..,.-~

As described above, the information recording and reproducing device of the present invention comprises a processing section which allocates units composed of collections of blocks on the recording medium so that the allocation information of the respective units on the recording medium and the 5 sector number information of the respective blocks of each unit are recorded in the predetermined unit information recording area of the recording medium. The processing unit reads the information every time the recording medium is loaded, and calculates physical sector numbers corresponding to the blocks of a unit specified by a host device during recording and reproducing operations 10 according to the read information. Therefore, allocation information of the respective units and sector number information of each block can be recorded in the predetermined unit information recording area on the recording medium by the present information recording and reproducing device. As a result, the host device can allocate information to blocks composed of the optimum number 15 of sectors according to the data length of the information, thereby allowing the recording area of the recording medium to be used efficiently. In case a disk (rewritable type) is used as a recording medium where information is recorded and reproduced in the constant linear velocity method, a reproduction operation for verification needs to be performed after the recording. Therefore, if the 20 block size of each unit is arranged so as to be slightly smaller than the number of sectors corresponding to a N-time disk rotation (N is a positive integral number), the wait time for starting the verification can be shortened, which permits the average speed of recording and reproducing data to be greatly improved. Furthermore, the host device can direct the information recording 25 and reproducing device to perform recording and reproducing operations by only specifying units and blocks.
Furthermore, especially in a case of applying the present invention to a rewritable-type recording medium, information can be erased unit-by-unit.
Therefore, it is possible to rearrange the erased unit to be a unit comprising 30 blocks of a different size, or to increase/decrease each unit size easily.

~A

Consequently, a recording and reproducing device which is capable of using a recording medium efficiently can be provided.
For example, with the present invention, it is possible to allocate a unit for information having the same format and other units for information 5 having different formats, and therefore information having various formats canbe recorded in a single recording medium. In addition, it is possible to easily erase only a unit containing unnecessary information. As a result, an erased unit can be used for recording information having one of the other formats recorded on the recording medium, or can be used as a new unit with a block 10 size which varies from the previous one and be allocated for recording information having a different format.
The invention being thus described, it may be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the scope of the invention.
There are described above novel features which the skilled artisan will appreciate give rise to advantages. These are each independent aspects of the invention to be covered by the present application, irrespective of whether or not they are included within the scope of the following claims.

~.~

Claims

1. An information recording and reproducing device for recording and reproducing information in a recordable-type recording medium block-by-block, wherein each block which is the minimum recording unit is composed of predetermined numbers of sectors, and wherein the sectors as recording areas are provided with physical sector numbers identifying each sector according to prerecorded absolute address information, the device comprising:
recording means for recording information in the recording medium; and, processing means for:
i) recording allocation information of units composed of collections of the blocks and sector number information indicating the number of sectors per block in each unit in said unit information recording area of the recording medium by the use of the recording means, the allocation information and the sector number information being given by a host device;
ii) calculating physical sectors corresponding to the blocks of a unit specified by the host device in recording and reproducing operations by reading the information recorded in the unit information recording area when the recording medium is loaded;
and, iii) directing the recording means to access the physical sectors.

2. An information recording and reproducing device as defined in claim 1, wherein the recording medium is provided with units composed of collections of the blocks and the number of sectors composing the blocks is arranged so that various types of information can be allocated to blocks composed of the optimum numbers of the sectors according to the data lengths of the respective information.

3. An information recording and reproducing device as defined in Claim 2, wherein the recording medium is shaped as a disc, and the unit is arranged such that block size Bs meets the criterion:

((m x n) - 0.5 m) < Bs < (m x n) where m is the number of sectors in one disk rotation in the innermost part of each unit and n is the number of tracks in one block, so that the time required for starting a reproducing operation for verification after completing the recording operation and for a track jump becomes substantially constant independently of the radial location on the recording medium.

4. An information recording and reproducing device for performing, recording and reproducing operations of information in a recordable-type recording medium block-by-block, wherein each block which is the minimum recording unit is composed of predetermined numbers of sectors, and wherein the sectors as recording areas are provided with physical sector numbers identifying each sector according to prerecorded absolute address information, the device comprising:
storing means;
processing means for recording allocation information of units composed of collections of the blocks on the recording medium, and sector number information indicating the number of sectors composing a single block in each unit in the storing means;
sub-code information generation means for generating sub-code information to specify the number of main information and sector numbers concerning recording start positions of the main information according to an output of the storing means;

recorded signal processing means for adding error detection and correction parity and the sub-code information to information to be recorded which is input from a host device, and for releasing signals which are modulatedbased on an EFM method and to which frame synchronization signals are added; and, recording means for recording the information in the recording medium according to an output of the recorded signal processing means.

5. An information recording and reproducing device as defined in claim 4, further comprising:
reproduced signal processing means for outputting to the host device reproduced signal data which is obtained after the reproduced signals go through the EFM demodulation process and an error detection and correction process using the error correction and detection parity; and, sub-code detection means for detecting the sub-code information from the EFM-demodulated reproduced signal;
wherein the processing means selects an output of the sub-code detection means, stores/reads it into the storing means, and stores/reads information which is related to the contents of TOC sent from the host device.

6. An information recording and reproducing device as defined in claim 1, further comprising:
file management means for managing files by providing a unit for recording file management information separately from a unit for recording files.

7. An information recording and reproducing device as defined in claim 6, wherein the file management information is equal to directory and File Allocation Table (FAT), information and track numbers and block numbers are included and recorded in the directory while block numbers are recorded in order in the FAT.

8. An information recording and reproducing device for recording together a group of information whose volume is fixed and a group of information whose volume varies, the recording being in a rewritable-type recording medium on which blocks are provided and numbered from an edge outward of the recording medium, the device comprising:
recording control means for controlling the group of information whose volume is fixed to be recorded from the largest block number toward the smaller block numbers and the group of information whose volume varies to be recorded from the smallest block number toward the larger block numbers, so that blank areas where neither of the group of information is recorded are present in one location.

9. An information recording and reproducing device for recording and reproducing information in a recordable-type recording medium, whose recording areas are provided with physical sector numbers according to prerecorded addresses, based on the non-completed interleaving method, the device comprising:
calculating means for calculating the physical sector numbers according to a block number, where the information is recorded or reproduced block-by-block;
recording control means for recording the information in the physical sectors calculated by the calculating means by dividing the informationby n numbers of effective sectors, generating and adding front additional data and rear additional data respectively in front of and behind the front and rear additional sectors for each information recorded in the respective effective sectors if the information is discrete information, and for recording information successively in the physical sectors if the information is successive information;
wherein each block is composed of (n + n, + n2) numbers of the sectors, a group of n numbers of the effective sectors, n, numbers of front additional sectors added in front of each group of the effective sectors, and n2numbers of rear additional sectors added behind thereto.

10. An information recording and reproducing device for recording and reproducing information in a recordable-type recording medium, whose recording areas are provided with physical sector numbers according to prerecorded addresses, based on the non-completed interleaving method, comprising:
calculating means for calculating physical sector numbers according to a block number where the information is recorded or reproduced by the block unit, wherein each block is composed of (n + n, + n2) numbers of the sectors; and, recording control means for recording the information by generating and adding front additional data to the front additional sectors of each block and rear additional data to the rear additional sectors thereof when recording low-volume information or information whose data lengths are not fixed, and for adding the front additional data only to n1 numbers of the front additional sectors of the first block and the rear additional data only to n2 numbers of the rear additional sectors of the last block when high-volume information is successively recorded over a plurality of blocks so that the information is successively recorded in sectors between the front additional sectors and the rear additional sectors.

11. An information recording and reproducing device as defined in claim 10, further comprising:
switching circuit means; and sector data generation circuit means for generating the additional data;
wherein the additional data is added to information to be recorded when the recording control means switches the switching circuit means.

12. A method for recording high-volume information over several blocks, comprising the steps of:
determining the sector number of the first sector of a block where the information is instructed to be recorded;

accessing the determined sector number, recording front additional data therein and recording the information successively in the following sectors;
and recording rear additional data in the last block after completing the recording of the information.

13. A method for recording low-volume information in each block, comprising the steps of:
determining the sector number of the first sector of a block where the information is instructed to be recorded;
accessing the determined sector number, recording front additional data therein and recording the information to the following sectors; and, recording rear additional data after completing the recording of the information.

14. An information recording and reproducing device as defined in claim 1, wherein the recordable recording medium is a rewritable-type recording medium, the capacity of the unit can be easily changed by erasing information unit by unit, and the number of sectors in one block in each unit can be rearranged to become larger from the inside to the outside of the recording medium, so that a single recording medium can be used efficiently.