US 3629835 A
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Description (OCR text may contain errors)
United States  Inventors William F. Brown Pawling, all of N.Y.
 Appl. No. 826,473
 Filed May 21,1969
 Patented Dec. 21,197!
 Assignee Texaco Inc.
- New York, N.Y.
 CREDIT CARD VALIDATION SYSTEM USING AN OPTICAL READER EMPLOYING REFLECTED LIGHT 2 Claims, 7 Drawing Figs.
 US. Cl 340/149,
 Int. Cl 1104: 3/00,
H04q 5/00  Field ofSearch ..235/61.l15; 340/149  References Cited UNITED STATES PATENTS 2,131,911 10/1938 Ayres ..235/61.l15 CR 3,025,495 3/1962 Endres 235/61.115 X 3,243,776 3/1966 Abbott et al.. 235/6l.l 15 X 3,365,568 l/1968 Germen 235/61.1l5
3,401,830 9/1968 Matthews. 235/617 B 3,456,997 7/1969 Stites 235/61.] 15 X 3,461,301 8/1969 Fitzmaurice 235/6l.l 15 X Primary Examiner-Harold l. Pitts Attorneys-K. E. Kavanagh, Thomas H. Whaley and Robert J.
ABSTRACT: Hereinafter disclosed is methodology and apparatus for optically reading, or recognizing, numbers on such articles such as credit cards and the like. According to one illustrative embodiment of the invention a credit card having an identifying number, or account number, consisting of a plurality of decimal digits is illuminated by a source of light. Reflected light from the face of the card is directed through a lens and projected on a mask which has a plurality of unique hole patterns therein. The light reflected from the digits on the card is considerably darker than the light reflected from other portions of the card. There is provided in the mask an individual pattern, or array, of holes for each digits reflected light. Each hole in each pattern of holes has associated therewith a photodetector. Hence, each pattern of holes has a corresponding pattern of photodetectors. For each of the decimal digits 0 through 9 on the card a unique pattern of illuminated and nonillnminated (or light and dark) photodetectors results. This unique pattern, or array, of light and dark photodetectors provides a unique set of signals which are representative of the particular decimal digit whose light has been reflected on the hole pattern in the mask. Ultimately, sets of such signals representing all the decimal digits are delivered to a comparator for the purpose of determining whether or not the number on the credit card corresponds to a like number stored in suitable storage means; said stored number also being delivered to the comparator.
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PATENTEB M821 1971 3529. 35
SHEET U UF 4 CREDIT CARD VALIDATION SYSTEM USING AN OPTICAL READER EMPLOYING REFLECTED LIGHT BACKGROUND OF THE INVENTION This invention pertains, in general, to character recognition apparatus; and, more particularly, to optically reading character, or numbers, on such articles as credit cards and the like.
Although the invention is hereinafter described, and illustrated in the accompanying drawings figures, as being useful in optically reading an identification number embossed on a credit card, it is to be understood that the inventions use is not limited to the optical reading of credit card numbers. Nor is it limited to numbers which are embossed or otherwise depressed or raised, although the invention has particular advantages when used for the optical reading of the embossed account, or identification, numbers.
One widely used form of credit card construction is the relatively thin plastic card which measures about 2% inches by 3% inches. The card bears an identifying number (e.g., l decimal digits) which is embossed by means of a die into the cards surface. More particularly, the embossing operation raises the digits upwardly on one face of the card and one the reverse face the embossed digits create a corresponding cavity or depression. Usually, there is a substantial amount of printed matter on either or both faces of the card. Very often a substantial amount of printed matter appears on the reverse face of the card and it overlays the embossed digits.
The credit card construction hereinbefore succintly and generally described is not entirely satisfactory for some methods of character recognition or reading. For example, in the mechanical sensing system of reading the embossed digits, or embossed marks representing digits, on the card face two cause, among others, of difficulty present themselves: (1) accumulation of dirt; and (2) distortion of the digits as occurs when the credit card is processes through an imprinter for making a receipt or invoice. The accumulation of dirt on and around the embossed digits, or characters, often interferes with the correct recognition of one or more digits and a false reading results. Distortion, or flattening and spreading, of the embossed digits caused by repeated processing in an imprinter similarly interferes with correct recognition and, again, false readings result.
SUMMARY OF THE INVENTION One object of the present invention is to correctly identify characters for, among other purposes, credit validation.
Another object of the present invention is to optically read identification characters, such as decimal digits, on an article, such as a credit card.
Another object of the present invention is to employ reflected light, or the absence or diminished intensity thereof, to optically read identification characters, such as decimal digits, on an article such as a credit card.
Another object of the present invention is to achieve the foregoing objectives with respect to articles, such as credit cards of the kind hereinbefore generally described, which have identification characters, such as decimal digits, which are embossed in said article, or credit card.
Thus, in accordance with an illustrative, not limiting, embodiment of the invention, there is provided methodology and apparatus for recognizing, or reading," the digits embossed on a credit card for the purpose, among other, of determining whether, because of fiscal history suitable stored, the card ought to be honored. Suffice it to say that the card is illuminated. Light is reflected from the illuminated face of the card. Each digit, or character, location on the card is comprised of an embossed portion representing the digit, or character, as well as a flat or plane portion. The plane portion reflects light impinging thereupon while the embossed portion (the digit, or character) can be considered to do either of two things: reflect no light at all; or, reflect light which is diminished in intensity. It makes no difference, conceptually. The important aspect is that there is a detectable difference between light reflected from the embossed and nonembossed, or flat, portions of the credit card.
Note that as and if, hereinafter, it is stated that diminished light, darker light, or recitations to like effect are employed it is to be understood that diminished light or darker light also may mean the absence of light. The light reflected from the embossed and nonembossed portions of the credit card are directed through a suitable lens and projected on to a mask. The mask includes for each embossed digit, or character, a unique pattern, or array, of apertures, or holes, which permit the reflected light to illuminate some photodetectors associated with the holes in said array and not illuminate other photodetectors associated with other holes in the array. The illuminated and nonilluminated photodetectors are instrumental in generating a set of signals which are representative of the light projected from the particular digit to be recognized or read." Finally, sets of such signals representing all the digits of the card's identification or account number are transferred to a comparator unit which compares, in effect, the card's digits with digits stored in a suitable memory unit or medium in order to establish whether a like set of digits, representing a particular identification number, exists in the memory unit. If, for example, delinquent account numbers are stored in the memory unit and one such number corresponds with the number on the credit card then appropriate action may be taken.
Other objects as well as the various features and advantages of the invention appear hereinafter where specific illustrative embodiments of the various features of the invention are set forth and described in detail with reference to the accompanying drawing figures.
i BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a diagrammatic illustration including block diagrams of the overall system according to the invention.
FIG. 2 is a frontal view of a typical credit card having an identification number embossed thereon.
FIG. 3 is a cross-sectional view through the credit card shown in FIG. 2, taken along the section line 33 therein.
FIG. 4 is a block diagram showing, among other things, the logic circuitry employed for determining one digit of the credit card identification, or account, number.
FIG. 5 is an illustration of the font employed for the decimal digits 0 through 9 and also shown in superimposed relation on each digit is a pattern, or array, of apertures, or holes, in a mask on which reflected light is projected.
FIG. 6 is a partial view of the mask employed for identifying the digits.
FIG. 7 is a diagrammatic illustration of an alternative system to that shown in FIG. I and employing optical fibers to transmit the reflected light to the apertured mask.
DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIG. I there is a provided a light source 10, which may be a conventional low-voltage filament-type bulb. Light, represented symbolically by the rays R, is directed through a lens 12 which, as indicated, refracts and directs the rays R onto the face of a reflecting medium 14 which also transmits light. Medium 14 may, for example, be a small piece of transparent window glass arranged at a 45 angle with respect to the plane of a credit card 16, as suggested in FIG. 1, so that the rays can be redirected to the face of the credit card 16. In the example shown in FIG. 1 the rays R are redirected by reflection from the glass plate 14 to that area of the face of the card which includes the raised embossed decimal digits representing the identification, or account, number. For details of the credit card see FIGS. 2 and 3. The redirected rays R are reflected from the card's face backwardly and these reflected rays, symbolically illustrated in FIG. 1, are identified as rays R The rays R,, are, as indicated, reflected toward the glass 14 which, being transparent, allows the rays R, to be transmitted to another lens 18.
The lens I8, as indicated, focuses the light rays R in such a way that they are directed to the face of a mask 20 and are spread out so that they cover a specific area on the face of the mask 20. This aspect is discussed in more detail hereinafter with reference to the discussion respecting FIGS. and 6. Suffice it to say at this point that the mask 20 has I0 sets or arrays of apertures therein; one such array serving, in the manner hereinafter disclosed, each of the I0 decimal digits, or digit locations, on the face of the credit card 16 and, more particularly, a corresponding digit location on mask 20.
In back of the apertures mask 20 there is positioned a plurality of photodetector arrays. These photodetector arrays are identified in FIG. 1 by the reference numbers 22a, 22b, 22c 22j. While many different kinds, or types, of photodetectors may be employed, the type herein contemplated, for purposes of illustration, is the photoconductive device; e.g., a cadmium sulfide cell which has a very high resistance in the absence of, or low-intensity, light and relatively low resistance in presence of light, or higher intensity light levels. As is described in more detail hereinafter each light projected decimal digit location on mask 20 has five apertures, or holes, arranged in a unique array (all the arrays, or patterns, for the assumed l0 decimal digits on the credit card being alike, however). In this respect, it has been discovered that the particular hole array herein employed enables recognition of all of the decimal digits 1, 2, 3, 4, 5, 6, 7, 8, 9, and 0 which have the form or font shown in FIG. 5. As an illustrative example used herein such font has been chosen, more or less arbitrarily, for the instant example as the type font identified as IBM I428 FONT. However, the instant invention does not depend on the use of the aforementioned font. The general principle of the invention obtains in respect of recognizing, or reading, digits of any form on the credit card.
Referring again to FIG. I behind the mask at each digit location (i.e., projected light digit location) there is the photodetector unit array 22a 22j. In other words, at each digit location behind the mask 20 there is located a photodetector unit, or assembly, comprising five photodetectors, or more particularly, five photoconductors (see FIG. 4); one photoconductor being registered with one hole in the five-hole array (digit location) on mask 20. As shown, each photodetector unit array 220 22j is coupled through an individual amplifier unit generally designated in FIG. I by the reference number 24. From the amplifier units 24 signals generated by the photoconductors are fed to logic circuitry 26 which, as is more fully explained with reference to FIG. 4, processes the aforesaid signals and decodes said signals for the purpose of determining which one of the decimal digits 0 through 9 is being red. From the decoding logic circuitry 26 the signals are routed to an encoder 28 which encodes the output signals from the logic unit 26 into binary signals. The binary encoded signals are delivered via the paths 28a ltlj to a comparator unit 30. Each path 28a 28j represents four channels for providing four binary signals, representing four binary bits for the decimal numbers 0 through 9. Thus, for an account number having 10 decimal digits 40 binary digits, or bits, are delivered to a suitable register having 40 bit locations suited in the comparator unit 30.
Also, as shown in FIG. 1, there is provided a memory unit 32 which includes suitable storage means for storing 40 binary digits, or bits, for each account number which is considered to be a delinquent account, signifying a poor credit risk. As shown in FIG. I the 40 bits representative of a particular account number are delivered via the paths 32a 32 from memory unit 32 to comparator unit 30. If all the bits delivered from the binary encoder 28 correspond with all the bits delivered from the memory unit 32 then the comparator unit 30 delivers an output signal identified as V The signal V may be used to drive a visible or audible alarm 34.
Show at FIGS. 2 and 3 of the drawings are illustrations of the kind of credit card herein employed. In FIG. 2 the front face of the credit card is shown and the decimal digits representing the account number appear thereon as indicated. The decimal digits representing the account number are embossed in the card and in the view shown in FIG. 2 the embossed decimal digits protrude outwardly toward the observer. FIG. 3 which is a cross section through the credit card shown in FIG. 2 illustrates the foregoing more clearly. For example, as shown in FIG. 3 the embossed decimal digits are comprised of a raised portion 16a on the front face of the card and a corresponding cavity 16b on the reverse side of the card.
Also, as is indicated in FIG. 3 when the reflected rays R, of light impinge upon the embossed or raised portion 16a of the card I6 reflected or redirected light rays R,,, are diffused in the manner suggested in FIG. 3. As a result, the reflected rays R return very little or no light back through the transparent medium 14 (see FIG. I). By contrast, as shown in FIG. 1 the rays R which are returned from the nonembossed face of the card to are returned in a greater quantity and ultimately are returned through the lens 18 to the mask 20.
At FIG. 5 there is shown the type font employed for the 10 decimal digits 1, 2, 3, 4, 5, 6, 7, 8, 9 and 0. As stated before, the type font employed herein is known as IBM 1428 FONT. In FIG. 5 there is superimposed on each of the decimal digit locations five dotted circles which are representative of five holes in the mask 20 shown in FIG. 6. It is to be noted that the pattern of five holes in the mask in FIG. 6 at each of the digit locations is a regular pattern. This is more clearly illustrated in FIG. 5 where the holes or dotted circles are superimposed at each digit location. It is to be noted that for each of the 10 digits the five-hole pattern is uniquely superimposed on each digit. In each five-hole pattern one or more of the holes may lie on the font representing the digit or one or more of the holes may lie on the outside of the font representing the digit. To illustrate this uniqueness more clearly, each hole in the five-hole pattern is identified as holes 1, 2, 3, 4, and 5 (see FIGS. 5 and 6). In table I, hereinafter appearing, if for example, hole I lies in superposition on the type font it is identified by the numeral 11f, however, it lies outside of the type font it is represented by l. The same is true for the holes 2, 3, 4 and 5. Of course it is to be understood that when any of the holes lies on the type font shown in FIG. 5 the hole is in the shadow of the projected image of the digit. If, however, the hole lies outside the type font it is outside of the shadow area. For ex ample, in FIG. 5 in numeral 1 the hole 1 lies in the light area rather than the dark area whereas in the digit 5 the hole number T lies in the darkened area. Hence, hole number I would be represented by l as far as digit 2 is concerned but as far as digit 5 is concerned it would be represented by the numeral I. All this should become clear by table I hereinafter appearing.
Let it be assumed that in FIG. 5 the decimal digits shown are projected on the mask 20 and thus for th e digit 6, as shown in table I above, the hole locations I, 2, 3, 4, 5 obtained and this represents the d ecimal digit 6. Similarly, decimal digit 4 is represented by I, 2, 3, 4 5. Thus, the bar represents light while the absence of a bar represents darkness or lower intensity light.
In FIG. 4 there is illustrated in block diagram form the logic circuitry 26 and the binary encoder 28 for a single digit position whereat a projected image of but one digit onto the mask 20 obtains. As indicated in FIG. 4 five photodetectors 40, 41, 42, 43, and 44 are provided behind each of the holes I, 2,3,4, and 5. The photodetectors 40 through 44 may be of the photoconductive type. The photoconductors 40 through 44 are directly coupled to the amplifiers 240 through 24c.
As indicated in FIG. 4 each amplifier 240 through 24c is directly coupled to the input of an inverter 45 through 49, respectively. As indicated the output from the amplifier 24a is designated as output l the output from the amplifier 45 is designated as output 1. Likewise, output from amplifier 24b is designated as 2 while the output from inverter 46 is designate as output 2. Likewise, output from amplifier 240 is designated as 3 while output from the inverter 47 is designated as output 3. Also, output from the amplifier 24d is designated as the output 4 w hile the output from the inverter 48 is designated as output 4. Finally, the output from amplifier 24e is designated as the output while the output from inverter 49 is designated as the output 5.
If, for example, hole number 2 is illuminated, the photodetector 11 will drive the amplifier and inverter such that the output 2 appears while the output 2 does not.
Th e outputs from the various amplifiers and inverters I or T, 2 or 2, etc. are used to drive the AND-gates 50, 51, 52, 53, 54, 55, 56, 57, 58 and 59. If, for example, the five holes and their associated photodetectors 40 through 44 were detecting the decimal signal 6 then the o utput from the amplifiers and inverters would be 1, 2, 3, 4, 5. Hence, the only AND gate to be driven would be the AND-gate 55 which would produce an gutput when all of its inputs were signals representing 1, 2, 3, 4, and 5.
The outputs from the AND-gates 50 through 59 represent the decimal digits 1 through 0, respectively. These outputs are coupled to the OR-gates 60, 61, 62, and 63. For example, the outputs from AND-gates 50, 52, S4, 56 and 59 representing the decimal digits 1, 3, 5, 7 and 9 are fed as inputs to OR-gate 60. The output from OR-gate 60 delivers a weighted binary bit in the least significant bit position. The OR-gates 60 through 63 represent the binary encoding portion of the circuit designated by the reference numeral 28 in FIG. 1. Similarly, the other decimal digit outputs from the various AND gates are indicated as driving the other OR-gates 61, 62 and 63 in the manner shown.
In FIG. 7 there is shown an alternative embodiment of the invention employing an optical fiber system. As shown, against the face of the credit card 16 there is composed an array of optical fibers. More precisely, there is one optic fiber bundle designated as by the reference number 70 which brings light from light source to the face of the card while another optical fiber 70a returns the reflected light from the face of the card to the mask 20. Advantageously, it is seen that by using the scheme shown in FIG. 7 that the size as compared with the scheme shown in FIG. 1 may be greatly reduced in that the distance from the face of the card 16 to the mask 20 may be greatly shortened. Moreover, the lens 12 and 18 as well as the transparent mirror 14 may be omitted.
While specific embodiments of the invention have been shown and described in detail to illustrate the application of the inventive principles involved, it is to be understood that the invention may be otherwise embodied without departing from the spirit and scope of the invention as hereinafter defined in the appended claims.
1. Apparatus for verifying the credit of a particular account, wherein said account is manifested by the presentation of a credit card having embossed thereon a plurality of decimal digits representing the account, comprising: a light source having light rays emanating therefrom; a transparent piece of flat glass arranged at a 45 angle relative to the plane of the credit card; a first lens located between the light source and the piece of glass for directing the light rays to the glass from whence the directed light rays are reflected from the window lass onto the credit card and onto the gmhossfid decimal igits thereon, said light rays being again reflecte from the credit card and from the embossed decimal digits thereon toward the transparent glass and passing through the transparent glass; a second lens located proximate to the transparent glass and receiving the aforementioned light rays reflected from the credit card and the embossed decimal digits thereon and passing through the transparent glass, said light rays reflected through the transparent glass from said embossed digits being of different light intensity according to the decimal digits 0 through 9; a mask, proximate to the second lens, said masks having for each set of reflected rays from said second lens a particular space for a digit location for each of the plurality of the embossed decimal digits on the credit card, each said digit location space on the mask being comprised of a set of five apertures, each set of the five apertures being uniquely responsive to the passing therethrough of the light rays of different light intensity uniquely characteristic of the decimal digits 0 through 9; means for generating sets of signals at each set of apertures in the mask in response to the reflected light thereupon onto said set of apertures, each set of generated signals being representative of an individual one of said decimal digits; means for encoding each set of generated signals in binary signal form; and, means for comparing said binary signals with other binary signals representing stored account numbers in order to verify the credit of the account number represented by the decimal digits on the face of the credit card.
2. Apparatus according to claim 1 wherein said embossed decimal digits are in the form of IBM 1428 font.