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Publication numberUS3671752 A
Publication typeGrant
Publication dateJun 20, 1972
Filing dateJan 5, 1970
Priority dateJan 7, 1969
Also published asDE2000441A1, DE2000441B2, DE2000441C3
Publication numberUS 3671752 A, US 3671752A, US-A-3671752, US3671752 A, US3671752A
InventorsSten-Lennart Bostrom
Original AssigneeSten Lennart Bostrom
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Locking device using radiation conducting key
US 3671752 A
Security locking device comprising mechanical locking means adapted to be electrically controlled, a source of laser radiation a plurality of opto-electrical transducers, a light conducting key insertable into a mating key hole and arranged to thereby connect the source with the transducers for transmission of laser radiation thereto to open the mechanical locking means.
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Description  (OCR text may contain errors)

United States Patent Bostrom [54] LOCKING DEVICE USING RADIATION CONDUCTING KEY [72] lnventor: Sten-Lennarl Bostrom, Box 607,

Hagersten, Sweden [22] Filed: Jan.5, 1970 [21] Appl.No.: 5,420

[30] Foreign Application Priority Data Jan. 7, 1969 Sweden; ..154/69 52 U.S.C|.. ..250/220R,250/227,250/209 51 lnt.Cl. ..H0lj39/l2 5s FieldofSearch ..250 221,2l6,234,206,209,

[56] References Cited UNITED STATES PATENTS 3,519,116 7/1970 Koehn ..250/227X 1 June 20, 1972 3,383,513 5/1968 Douglas ..250/210 X 3,142,761 7/1964 Rabinow ..250/219 3,532,434 10/1970 Jones, Jr. et a1. ....250/22O 3,068,362 12/1962 Ruocchio et a1... ..250/225 3,120,125 2/1964 Vase] ...250/227 X 3,328,790 6/1967 Rhodes ..250/209 X Primary ExaminerWa1ter Stolwein Attorney-Hammond & Littell 5 7] ABSTRACT Security locking device comprising mechanical locking means adapted to be electrically controlled, a source of laser radiation a plurality of opto-electrical transducers, a light conducting key insertable into a mating key hole and arranged to thereby connect the source with the transducers for transmission of laser radiation thereto to open the mechanical locking means.

8 Claims, 4 Drawing Figures PATENTiflJuuzomn n 3.671.752 sum 10F 3 UBGYR INVENTOR.


ATTORNEYS fen-Leann aos'rnou.

LOCKING DEVICE USING RADIATION CONDUCTING KEY The present invention relates to a locking device, having a practically unlimited number of possible combinations and is wholly secure against any unauthorized use and furthermore, cannot possibly be copied.

For this purpose a locking device according to the invention comprises a transmitter for laser radiation by optical or electrooptical means can be directed towards desired targets, a receiver comprising said targets and arranged to actuate a connecting means, and a key, which is insertable between the transmitter and the receiver in order to direct the radiation to said desired targets.

The receiver can be arranged to electromagnetically control connecting means for a mechanical lock, and the key can be arranged, when inserted in a keyhole, to actuate means for the connection of the radiation source. The key can be provided with manually operative means in order to actuate one or several radiation paths or the radiation intensities through the key to the receiver. The receiver can comprise one photoelectric cell for each one of the targets, and said cell can be allotted an amplifier and each amplifier can be arranged to actuate a flip-flop, when it receives a determined voltage from its photoelectric cell. A number of flip-flops are arranged to control a gate unit provided with a series of inputs and arranged to control a means intended to actuate the connecting means, when a predetermined input condition pattern is present.

The radiation can comprise a number of radiation components of different wave length being arranged selectively to be directed towards different targets. Said components can be polarized in different ways. The key is suitably arranged to control or convey radiation along different paths of direction in the key to one and the same or to different targets. Thereby the key can damp or polarize different radiation components in different manners. The key can be arranged to refract or diverge different radiation components to different parting points from the key which points are located right in front of respectively corresponding targets of the receiver.

The paths of direction for different radiation components in the key, by way of example, consist of transparent material in an otherwise opaque key. The key can suitably be provided with portions having different optical qualities for different paths of direction and/or radiation components through the key. The key can suitably be provided with color filters for different color components contained in the radiation spectrum and also with polarization filters for different components contained in the radiation spectrum. The key can also. be provided with distinct prisms in order to diverge different color components of the radiation in a different way. The gate unit is suitably comprised of a number of serial steps of parallel simple AND-gates and/or OR-gates. In the example of embodiment described, the key is provided with an axial bore, to which the radiation of the transmitter is directed, and a number of cross bores or output terminalscutting the path of the axial bore, to which cross bores different components of the radiation can be selectively directed for transmission to opposed target channels in the walls of the keyhole.

In accordance with the present invention there is provided a locking device comprising electrical coupling means controlled by a key and preferably adapted to control a mechanical lock in an electro-magnetic way, characterized by a transmitter for laser radiation or other optical radiation, a receiver having a plurality of discrete target points excitable by said radiation, an equal plurality of opto-electrical transducers, one assigned to each target point and each transducer being arranged to actuate a corresponding coupling means upon the excitation of the target point assigned thereto, and a key being insertable between the transmitter and the receiver and arranged to selectively control and/or direct said radiation to a number of predetermined target points of the receiver.

The invention will now be described more in detail with reference to the accompanying drawing illustrating an example of an embodiment, in which:

FIG. 1 shows a key inserted in its key hole,

FIG. 2 shows a cross section at right angle to FIG. 1,

FIG. 3 shows an example of a gate unit, and

FIG. 4 shows a number of suitable elementary types of gates.

As is evident from FIG. 1, the key N on its handle portion is provided with a dial IS having a graduation with figure indications, and said handle is also provided with an index mark IM. The figure graduation is illustrated with eight division units 1-8. Another corresponding dial can be provided on the opposite side of the handle. Instead of, or in addition to, the dials one can have one or several rotatable rings with figure indications to make possible the proper alignment of the figures of a code number of several digits in a manner known in connection with cipher code locks and combination locks. In order to simplify the description it is assumed that in the present example there is only one dial IS and that said dial, via a coupling arm RM, actuates the setting means of the key which will be described in more detail below. The position of the dial in the illustration with the digit 3 set adjacent to the index mark IM is assumed to be the right code position for the key in question.

When inserting the key N in the keyhole, the end of the key actuates a contact K located in the bottom of the hole. The contact K connects a laser beam LS, which is directed through a hole 10 towards a bore 11 in the key. The bore can be filled with a transparent material, e.g. crystal glass or other material of similar optical properties. The laser beam LS is assumed to be polarized and composed of by five color components, namely one blue B, one green G, one yellow Y, one red R, and one ultraviolet component U.

The blue component B of the beam hits a first edge 12 of a prism in the bore 11 and is reflected by said edge through a cross bore and further a second edge 13, from which it is reflected in the opposite direction through a cross bore 101 extending in the other direction.

In an analogous manner, the green radiation component G is reflected through cross bores 102, 103, the yellow component Y through cross bores 104, 105, the red component R through cross bores 106, 107, and the ultraviolet component U through cross bores 108,109.

The indications corresponding to the difierent colors B, G, Y, R, U have been placed above the cross bores 100, 102, 104, 106, 108 and the upper edge of the key, but in order not to complicate the drawing, they have been left out at the bores 101, 103, 105, 107, 109 located at the opposite edge, but it is understood that the last mentioned bores receive beams of the respective corresponding colors in the same consecutive order. Each cross bore 100-109 comprises a color filter indicated with F1-F5, said filters only being marked with indications for the left column of bores. These filters only let through the color component related to the bore in question. Further, each cross bore has a set of polarization filters Pl-PS belonging thereto, indications only being inserted for the left column of bores. Of these sets of polarization filters P1-P5 the ones located in the bores 103 and 106 (P4) are adjustable by means of the belt RM connected with the dial IS. As a result, this degree of light which is transmitted through these filters can be varied by rotating said dial IS.

In FIG. 2 a cross section through the key N is shown, and it is evident that in this embodiment there are provided four series of rows of cross bores CHI-CH4, of which the series CH1 represents the bores 100, 102, 104, 106, 108 and the series CH3 represents the bores 101, 103, 105, 107, 109. In the bore 11 the spiral arrangement of the reflection edges 12, 13 is shown.

As is shown in FIG. 1, the cross bores 100-109 are set directly adjacent the corresponding channels or target terminals 200-209 in the lock, and in the lower row of channels the channels 201 and 209 are shown provided with polarization and color filters PF] and PFS belonging thereto. Each channel 200-209 has, of course, an own corresponding polarization and color filter, although in order to simplify the drawing these have been omitted.

Counted in order from the key N, the channel 201 is allotted said filter PF], a photoelectric cell PHI, and amplifier NVI, a flip-flop FFl, and an output U1. The channel 209 is shown and is allotted the corresponding units PFS, PHS, NVS, FFS and U5. The outputs are shown as being unipolar, but are in reality assumed to be bipolar, as will be evident from the following.

The said outputs UI-U5 are connected with a gate unit GK, which will be described more in detail below, and in turn they are connected control a lock gate GL operating a magnetic lock.

At this stage of the description it is certainly understood that a locking device of the type described permits a very great number of possible combinations.

Thus because of the nature of the laser beam one can obtain a very great number of distinct color components, each one having a well defined wave length. Here only five different wavelengths (colors) have been described.

' Further each one of these color components can be polarized in many different ways. Below, only three different polarizations of the incoming colors are dealt with, but intermediate degrees of polarization are also available for use.

In addition with the help of the sets Pl-PS of polarization filters it is possible to obtain a great number of light intensity levels. Only four resulting light levels for the respective photoelectric cells PH lPH5 are dealt with below.

Finally, it is possible to use one or several of the series CHI-CH4 of cross bores illustrated, and further this number can be increased considerably above the number of four mentioned. In the example described only one such series is used, namely CH3.

The gate unit GK illustrated in FIGS. I and 3 can be made in a great number of different variants of combination. In FIG. 4 a table of different types are shown, namely eight simple gates, which can be used in the assembly of gate unit GK.

In the left column of FIG. 4 four types of AND-gates, in the middle column four types of OR-gates and in the right column a table of the input and output conditions of said gates are shown. The inputs of the gates are indicated with a and b and the outputs with 1. Only gates with each two inputs 0, b, and one output z are shown. However, it is evident that a great number of other types of more complicated gates can be used for the assembly of the unit GK.

In the right column the inputs a and b and the outputs z are shown with the corresponding conditions indicated with L and H, respectively, which by way of example can mean low voltage and high voltage, respectively. The top square of the right column thus indicates that for the adjoining AND-gate and the adjoining OR-gate the input condition L on both a and b gives the output condition L on 1, that H and L respectively and L and H respectively on a and I; give L on 1, while H on both a and I) gives H on z.

In FIG. 3 an example of the structure of the circuit GK is illustrated using only AND-circuits according to FIG. 4, which AND-circuits are indicated with O,P,Q,S in order to facilitate their identification. As mentioned, the output terminals Ul-US illustrated as unipolar terminals are, in fact, bipolar terminals and have been provided with the indications L and H analogous to the table in FIG. 4. It is assumed that the flipflops FFl-FFS are all in the setup positions and their output terminals then have the conditions L and H from left to right of all outputs Ul-US as is shown in FIG. 3. In the resting condition each gate is assumed to have reversed out conditions on both their terminals as shown in FIG. 3, i.e. H and L. The conditions L and H have been indicated on the inputs and outputs of all the gates shown in FIG. 3 in order to facilitate the understanding of the logic function of diagram in the diagram. The indications O, P, Q, S according to FIG. 4 also appear in FIG. 3. In the condition illustrated in FIG. 3 the unit GK gives the condition L to the locking gate GL in order to open the magnetic lock. It is understood that FIG. 3 therefore corresponds the condition L and H on the respective positions obtained by inserting the correct key in the key hole.

More exactly defined, the four gates S, Q, 0, P are connected with eight of the terminals L and H from Ul-US,

whereby only L from U3 and H from US are not connected to the gates. Said four gates are in pairs connected with a second series of two gates Q and F, which in turn have a common connection with a third series comprising only one gate of the type P. It is understood that each reversal of the condition of one or several of the terminals Ul-US will change the input conditions of one or several of the gates, so that the end result will be the output condition H from the last gate P, which is connected directly with the locking gate GB, so that said last mentioned gate cannot actuate the magnetic lock.

In the following detailed description of the functioning it is in the first place assumed that the correct key has been inserted in the key hole. When said key has been inserted to the bottom, the laser beam LS is connected. It is assumed that the input polarizations for the color components are for the blue B polarization, 180 for the green G, 180 for the yellow Y, 90 for the red R, and 45 for the ultraviolet U. If the dial IS is set on the correct value 3, it is assumed that the different level deciding polarization filter sets PI-PS are set for the respective polarizations 45, 60, 30, 30, and 45 for the colors B, G, Y, R and U. Then said color components in consecutive order will be let through the respective channels 203, 205, 207, 209 with the levels 50, 30, 60, 30, and percent to the corresponding photoelectric cells pHl-PHS. The voltages obtained from the photoelectric cells are amplified in the amplifiers NVl-NVS, belonging thereto with each amplifier having a lower and an upper threshold, which must not be exceeded. It is assumed that the voltage 6 volts corresponds to a color intensity of 50 percent, which in the present case shall be reached by the tension (voltage) signal of the blue component. Thus the lower threshold of 6 volts shall be reached, but not exceeded to any substantial degree for the amplifier NVI. With the levels assumed for the other color components corresponding values for the other amplifiers NV2-NV5 shall be -3.6 volts (30 percent), 7.2 volts (60 percent) 3.6 volts (30 percent) and -12 volts (I00 percent). With these values are reset the flip-flops FFl-FFS and low voltage L or high voltage H is received according to FIG. 3. In comparison with the table of FIG. 4 it is evident that thereby the conditions shown on the inputs and outputs of the different gates S, O, Q, P, Q, P and P will be obtained. Thereby the correct low input condition L to the locking gate GL will be obtained, which then automatically opens the magnetic lock. I

If, on the contrary, an incorrect key N is inserted in the lock and it is assumed that for said key everything is in accordance with the correct key, except the polarization 45 for the color component U, an incorrect level is obtained in the amplifier NVS of the channel 209, so that the flip-flop FF5 cannot be actuated. On the output terminal US of said channel the condition l-I,L is obtained instead of L,H (FIG. 3), because of which the gate P is actuated with the input conditions L,H and then gives the condition H on its output terminal instead of L, as per FIG. 4. The gate P in the second row in FIG. 3 then incorrectly receives the input condition L,H instead of L,L, and gives out H (as per FIG. 4) instead of L to the gate P in the third row in FIG. 3, which then receives the input condition L,H instead of L,L and then gives out H instead of L, as a result of which the locking gate LG cannot be brought to function and actuate the magnetic lock.

It has been mentioned above that a very great number of combinations can be obtained with a locking device according to the present invention by using a great number of color components, many cross bores per series and many series of cross bores in the key, a great number of polarizations and levels and a gate device, which for the purpose has many more gates than has been shown.

However, very little has been said about possible modifications in relation to the mechanical structure, but it is obvious that the key provided with bores but for the rest being opaque and having reflecting edge portions at the cross bores along a helical edge curve, as described in FIG. 3, is not a very refined design from a mechanical viewpoint. It has been mentioned above that the so-called bores do not necessarily have to be real hollow spaces, but that they can be filled with transparent material, as for example crystal glass, the remaining portion of the key being made of opaque key material. However, it is more probable that in practice a key would be designed employing lenses, mirrors, prisms and other optical elements instead of bores with reflecting edge portions. Because of the known coherence and other qualities of the laser beam it is obvious that with simple optical means it is possible to divide or spread, refract or diverge and reflect and filter such a beam with considerably simpler means than can be understood by the above embodiment. in other words, laser beams are considerably better suited than common light in order to obtain selective division into monochromatic monotype beams of a very small cross section. Therefore, applying the known optical laws and using very small optical components it is possible to obtain a whole series of well defined small points (spots) on a receiving surface without using any bore according to FIG. 1. The key can further be completely transparent and can even be shaped in such a way that no individual optical components can be discerned with the naked eye, by for example having different portions of the key made of material of different optical qualities. Such optical qualities can, for example, comprise the refractive power, the polarization, the opacity, and the color transmission.

In conclusion, it is understood that a locking device according to the invention lends itself to be made in a practically unlimited number of combinations and that therefore one never needs to have two completely identical locks and keys. In reality it is quite possible to allot each individual a unique key and thus use such keys for the purpose of identification of persons. It is further understood that it is completely impossible to copy such a key, if it is made according to'the present invention as described above, because it is for all practical purposes impossible to measure the data of such a key and then make it without having access to the manufacturing equipment of the manufacturer.

In the description above only laser radiation has been dealt with, but it is of course obvious that other type of radiation, which can be diverged and spread and in essential respects behaves in a way analogous to laser radiation can be used within the scope of the invention. It can also be imagined that electronic radiation and other particle radiation and, for example, electronic optics can be used in certain special connections. For the purposes more specifically related here, it appears, however, that laser radiation due to its ability to be used in conjunction with very small components, from a practical viewpoint would be preferable in all applications, which at present can be anticipated.

It is further understood that the laser radiation can be used for obtaining a starting and feeding action in the key of means for generation and direction of other kind of energy than laser energy to said targets, for example by means of solar cells actuated by the laser radiation.

The invention has been described above in connection with a simple embodiment and a number of modifications have been schematically dealt with, but it is understood that the idea of the invention is not limited only thereto, and as to its scope it only can be limited by the accompanying claims.

What I claim is:

l. A security locking device comprising a. mechanical locking means adapted to be electrically controlled,

b. a source of laser radiation,

c. a receiver for said laser radiation,

d. a key insertable into a mating key hole means and arranged to thereby connect said laser radiation source with said laser, radiation receiver for transmission of laser tributed and spaced according to said first pattern, each output terminal being arranged, upon the correct insertion of said key into said key hole means, to cooperate with a respective target tenninal to supply laser radiation thereto.

g. a plurality of laser radiation paths within said key, each of said paths leading from said laser radiation source to at least one of said output terminals,

h. a plurality of components comprised within said laser radiation paths and arranged to modify predetermined characteristic properties of laser radiation propagated along said paths, to thereby generate output conditions on said output terminals according to a second predetermined pattern specific for said key,

a plurality of opto-electrical transducers, each having an input connected to at least one of said target terminals and each being arranged to generate an output signal when receiving as an input a predetermined value of some characteristic property of said laser radiation, and j. plurality of electrical circuit means, each connected to a respective of said transducers and arranged to be actuated when receiving an input signal from said transducers, said circuit means being arranged to be actuated according to a third predetermined pattern when said second preterrnined pattern corresponds to the pattern of predetermined input values to said transducers, and said third output pattern being effective to open said mechanical locking means.

2. A locking device according to claim 1, wherein said laser radiation comprises a number of components having different wave lengths, said components being arranged to be directed by said key to different target terminals.

3. A locking device according to claim 1, wherein said laser radiation comprises a number of components having mutually different polarizations, said components being arranged to be directed by said key to different target terminals.

4. A locking device according to claim 1, wherein said key comprises a plurality of regions having predetermined different optical characteristics selected for at least one predetermined optical effect on at least one predetermined characteristic property of laser radiation passing through each of said regions.

5. A locking device according to claim 1, wherein said key is arranged to actuate a starting means for said laser radiation source upon insertion of the key into said key hole means.

6. A locking device according to claim 1, wherein said key is provided with manual control means for modifying at least one of said laser radiation paths and laser radiation intensities through the key to said receiver.

7. A locking device according to claim 1, wherein said laser radiation receiver comprises one photoelectric cell per target terminal, where an amplifier is connected to each photoelectric cell and each amplifier is arranged to control a flip-flop upon receiving a predetermined voltage from its corresponding photoelectric cell.

8. A locking device according to claim 7, wherein a number of said flip-flops are arranged to control a gate unit, said gate unit comprising a number of series stages of elementary parallel gates and a series of inputs, and said gate unit being arranged to control said mechanical locking means upon the appearance of a predetermined pattern of input conditions on said series of inputs.

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Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US5043593 *Jul 10, 1989Aug 27, 1991Kokusan Kinzoku Kogyo Kabushiki KaishaOptical theft deterrent system
US5055668 *Mar 22, 1990Oct 8, 1991Nissan Motor Co., Ltd.Photo-sensor cell suitable for IC chip
US5119065 *Jan 14, 1991Jun 2, 1992Wiehagen Fred AVehicle protection system
US7138903 *Jun 2, 2004Nov 21, 2006Jian-Choung DoongLock module using colored light rays to identify the application of an accurate key
US8922333Sep 10, 2013Dec 30, 2014Gregory Paul KirkjanContactless electronic access control system
US20050270767 *Jun 2, 2004Dec 8, 2005Jian-Choung DoongLock module using colored light rays to identify the application of an accurate key
DE2516283A1 *Apr 14, 1975Oct 21, 1976Nixdorf Computer AgMultiple key locking control system - has system of light beams within lock barrel itself corresponding to cut pattern of key
WO2003104590A1 *Jun 6, 2003Dec 18, 2003Codixx AgOptical security system
U.S. Classification250/208.4, 70/277, 250/226, 250/227.21, 70/DIG.510
International ClassificationB60R25/02, E05B49/00, E05B19/00, G02F3/00
Cooperative ClassificationG02F3/00, E05B49/006, Y10S70/51
European ClassificationE05B49/00M4, G02F3/00