Optoelectronic lock with optical guides

Abstract: The present invention is an optoelectronic lock using optical guides. It is designed to prevent access to areas, vehicles and machines. It basically consists of a lock cylinder (24), normally located in the object to be protected, an optoelectronic module (12), one or more optical guide collectors (9), a set of optical guides (8) assembled in a cable (11), a source of electromagnetic radiation (6) and one or more keys (25). The lock cylinder (24) incorporates a lock-identifier (1) with N 2 cross keyholes (7), each of which contains the tip of an optical guide (8). The key (25) is fitted with a key-identifier (2), the shape and dimensions of which are perfectly adapted to those of the lock-identifier (1), and which have a longitudinal keyhole (4) from which a number of radial keyholes (3) branch off; the latter are positioned in such a way as to coincide with some of the cross keyholes (7). The longitudinal keyhole (4) contains the optical guide (82) which branches off through the radial keyholes (3) to form the optical guides (83).

Description: Technical nature of the invention: The present invention is an optoelectronic lock which uses optical guides. It is designed to protect access to areas, vehicles and machines and is specially suitable for uses reduiring high degrees of security. Technical background: In efforts to improve upon the security provided by conventional mechanical locks, electronic locks and security systems - especially those using optoelectronic technology - have in recent years undergone constant advances. The optoelectronic locks and security systems currently in existence can basically be grouped into three different categories, all of which incorporate a lock cylinder fitted with one or more photoelectronic pairs and operate by means of an electronic circuit. Each photoelectronic pair operates by means of a light-emitting diode positioned on one side of the keyhole. On the opposite side is a photodetector. When the key is introduced into the keyhole, only some of the photodetectors receive light. The first type of lock, a description of which may be found in European Patent Application no. 85440011 by Radosavljevic, Milenko operates by means of a key with perforations in certain places which correspond to the arrangement of the photoelectronic couples. When inserted into the keyhole, the key allows some photodetectors to receive light while covering others. The electronic circuit then interprets the configuration of lit and unlit photodetectors to decide whether the key introduced is the correct one or not. The second type of optoelectronic lock is a lock opening system which is proposed in Canadian Patent no. 1 057 377 by Diez, Angel and which uses a key consisting of a ring having a light decoding unit on its top. The light decoding unit is a pyramid-shaped block having inside a network of optic fibers connecting a set of light receiving points placed in one face of said pyramid-shaped unit to a set of light emitting points placed in another face of that unit, according to the particular code of that key. When the key is introduced into the keyhole, the output pattern of light emitting points is sent to a light-current transducer which generate an electric code which is checked against the internally programmed codes. The third type of optoelectronic lock adopts a different approach, as described in International Patent Application PCT/US88/03345 by Pinnow, Douglas. This type operates by means of a single photoelectronic couple, which optically reads the contours of a conventional key. The first and third type of locks nevertheless have the disadvantages of allowing only a small number of combinations and of using keys which are easily reproduced. Furthermore, all three types of locks have the photoelectronic pairs and even sometimes, the electronic circuit, inside the lock cylinder, which must be partially accessible from outside. Therefore, in many cases, it is possible to circumvent the locking system simply by the manipulation of the electric connections in the interior of the lock cylinder. The third lock type has the added disadvantage of requiring a highly complex electronic circuit, which requires a microprocessor and is difficult to calibrate. This makes it prone to malfunctions and also reduces the security: price ratio. The above observations lead us to appreciate the need for an optoelectronic lock which allows far greater security than that offered by those which currently exist. Such security involves the use of keys which are more difficult to reproduce, a system allowing a greater number of combinations and the avoidance of electrical wires in the lock cylinder itself, which might let the lock to be unlocked without the proper key. The advantages of the lock of the present invention: This new lock overcomes the disadvantages and inconveniences of the optoelectronic security systems and locks currently in use by means of optical guides fitted in the lock cylinder and used in its connection to a remote optoelectronic circuit, and furthermore by the use of another device which we shall designate as an optical guides "collector"; therefore it has the following advantages: Absence of electrical contacts inside the lock cylinder, which make it easy to "jump" the lock mechanism; Use of keys which are difficult to reproduce; Absolute flexibility of the format of the keyhole/slot in which the key is introduced; Lock cylinders which, for the same dimensions, allow a far greater number of combinations; The number of photodetectors required for such a large number of combinations is much smaller than it would be with previously-existing systems thanks to the use of the aforementioned optical guides collector. A brief description of the diagrams: Fig. 1A is a schematic illustration of the principal components of the lock and their interconnection; Fig. 1B is a simplified longitudinal section of a possible key-identifier inserted into a given lock-identifier, both incorporating respectively in the radial holes 3 and cross holes 7, graded-index rod lenses; Fig. 2A is a frontal view of a lock cylinder fitted with an octagonal keyhole and incorporating a shutter and pin tumblers; Fig. 2B shows a cross section of the above lock cylinder; Fig. 2C shows the same lock cylinder in longitudinal section; Fig. 3A shows a top view of a possible key for the lock cylinder shown in figs. 2A, 2B and 2C; Fig. 3B shows a longitudinal section of the same key; Fig. 4 is a simplified illustration of a optical coupler/combiner fitted with graded-index rod lenses; Fig. 5 is a simplified illustration of the longitudinal section of a possible optical guides collector using biconvex spherical lenses and with a built-in photodetector; Fig. 6A shows a longitudinal section of a lock cylinder of the flat variety of the present invention; Fig. 6B shows the longitudinal section of a key for the lock cylinder illustrated in fig. 6A; Figs. 7A and 7B show frontal views respectively of the above lock cylinder and key. Detailed description of the basic configuration: The present lock basically comprises a lock cylinder 24, normally fitted to the object to be protected, a remote optoelectronic module 12, a set of optical guides 8, usually grouped in one or two cables linking the lock cylinder 24 to one or more optical guides collectors 9 and the optoelectronic module 12, and one or more keys 25. The principal element of the lock cylinder 24 is a component which we shall designate as a lock-identifier 1. This differs from lock to lock and is basically, as fig. 1A shows, cylindrical or prism-shaped. It can be made of steel, brass or any other material or combinations of materials. This lock-identifier 1 has a lengthwise hole which can be square, rectangular, circular or hexagonal (or other) in section and is the keyhole 16 in which the key 25, or part of the key, is inserted, except for the flat variety of the present lock, which has not a keyhole or has a different one. The lock-identifier. 1 is also fitted with a series of N 2 cross holes 7 (N 2 being any whole number greater than zero) arranged either in a pattern or at random and in different positions for each lock-identifier, each of which perforates it from the external surface to the aforementioned keyhole 16. The cross holes are normally circular in section with a diameter usually ranging from two to five millimetres. In each cross hole 7 is the end of one optical guide 8, the other end of which is connected to an optoelectronic device 10 or to the optical guides collector 9 (see fig. 1A). Optoelectronic devices 10 (e.g. photodiodes, phototransistors, photoresistors etc.) convert optical (luminous) signals into electric signals. We shall refer to these simply as photodetectors. They are normally incorporated into the optoelectronic module 12. In certain versions, each photodetector is associated to an electronic circuit which preamplifies the electrical signals produced. The optical guides collector(s) 9 is (are) optical or electro-optical device(s) which combine in a single output - normally an optical guide - the electromagnetic radiation proceeding from any of the optical guides 8 connected to its inputs. They may be positioned in the lock cylinder 24, in the optoelectronic module 12 or at any intermediate point between the two. As for the key 25, this incorporates a component which we shall designate as a key-identifier 2. The key-identifier 2 is of a shape and dimensions which allow it to be neatly inserted into the keyhole 16. It is normally made of material(s) similar to those used for the lock-identifier 1 and has a longitudinal hole which does not generally span its length. The longitudinal hole intercepts a series of N 1 radial holes 3 in the key-identifier 2. These radial holes 3 are identical in format to the cross holes 7 and have a diameter which is equal to or slightly less than the diameter of the latter. Their number N 1 is, in the basic version, smaller than the number N 2 of the aforementioned cross holes 7, often half or less than half the number. The radial holes 3 are positioned on the surface of the key-identifier 2 in such a way that when the key-identifier is inserted fully and correctly into the lock-identifier 1 for which it was made, all its radial holes will coincide with some of the cross holes 7 of the latter. Thus, for example, if N 1 = eight and N 2 = sixteen, the key 25 belonging to a certain lock will in these conditions incorporate a key-identifier 2 with eight radial holes 3, which will coincide with eight of the sixteen cross holes 7 of the lock-identifier 1 of the corresponding lock (when the key 25 is correctly inserted). The N 1 cross holes 7 which coincide with the N 1 radial holes 3 of the correct key-identifier 2 are those whose optical guides 8 are connected directly and individually to photodetectors 10, while the remaining N 2 -N 1 cross holes 7 are those whose optical guides 8 are connected to the inputs of the optical guides collector(s) 9. Each radial hole 3 contains in its interior an optical guide 83. Together in a beam these form the optical guide 82, located in the interior of the longitudinal hole 4 of the key-identifier 2. Both the optical guides 8 and the optical guides 83 are of a diameter equal to or slightly less than the diameter of the holes in which they are inserted (the cross holes 7 and the radial holes 3 respectively, except in versions containing microlenses) and normally comprise one or more optical waveguides designed to conduct electromagnetic radiation from the optical spectrum, i.e. light radiation from either the visible or invisible spectrum. These optical waveguides normally operate by means of the principle of total internal reflection and are of the type normally designated as optical fibres. Usually the employed fibres are multimedia step index fibers. More economical versions may use plastic optical fibres. When the key 25 is correctly inserted into the lock cylinder 24, its key-identifier 2 fits entirely into the lock-identifier 1 and the source of light 6 is activated. This source may consist of one or more LEDs, one or more small lasers or even a small light bulb. In every instance, the wavelength of the radiation emitted is suited to the type of optical waveguides and photodetectors used. When the source of light 6 (located in the key 25, the optoelectronic module 12, the lock cylinder 24 or elsewhere, with the latter instance requiring an additional optical guide to transmit the emitted radiation to the lock cylinder 24) is activated, the radiation emitted is focused by one or more lenses 5 onto the extremity of the optical guide 82, which, by means of the optical guides 83 which comprise it, transmits it through the interior of the key-identifier (2), from where it is propagated via the radial holes 3. Here, in the radial holes 3 which coincide with the cross holes 7, the light is transmitted to the respective optical guides 8 and from here to the corresponding photodetectors 10 or the optical guides collector 9, depending on the case. Transmission does not occur when any of the radial holes 3-does not coincide with a cross hole 7. If the key inserted is the correct one, each of the radial holes 3 will coincide with a cross hole 7, whose optical guide 8 is directly connected to a photodetector 10, while none will coincide with a cross hole 7 connected to the optical guides collector 9. Thus, all the photodetectors 10 except the one connected to the output of the collector will be activated. The electrical signals generated by the photodetectors will then permit the electronic circuit of the optoelectronic module 12 to determine if the inserted key is the correct one and in the affirmative case it will activate the required functions. If the key inserted is not the right one, not all the photodetectors 10 connected directly via the optical guides 8 to cross holes 7 will receive radiation, and/or the photodetector 10 connected to the output of the optical guides collector 9 shall be activated. This means that one or several of the radial holes 3 coincide with cross holes 7 connected to its inputs via optical guides; therefore the output of the optoelectronic module 12 shall fail to perform the desired functions. Radial holes 3 and cross holes 7 with incorporated microlenses: In order to reduce transmission loss between the optical guides 83 and the optical guides 8 which coincide with them - loss which is unavoidable owing to the necessary distance between their extremities - and to reduce the diameter of the optical guides used and consequently of the cables linking the lock cylinder 24 to the optoelectronic module 12 and to the optical guides collector(s) 9, some versions of the present lock are fitted with microlenses in their cross holes 7 and in the radial holes 3 of the key-identifier incorporated into the respective key(s) 25. These microlenses may either be conventional spherical lenses or graded-index lenses. Fig. 1B shows a simplified longitudinal section of a given key-identifier equipped with graded-index rod lenses, which is inserted into a given lock-identifier similarly equipped with the same type of lens. In the illustrated example, the lenses have a focal distance equal to the distance between their faces and therefore the ends of the optical guides are in direct contact with their inside faces. In this way the diverging beam of radiation at the end of each optical guide 83 is collimated by the corresponding lens 86, which is located in the respective radial hole 3. If the latter coincides with a cross hole 7, the beam of parallel rays will strike the lens 87, which will focus the beam on the end of the corresponding optical guide 8; thus the transfer of radiation between optical guides 83 and the corresponding optical guides 8 occurs with an enormous reduction in loss by longitudinal misalignment. In these versions, the optical guides 8 and optical guides 83 consist of only one optical waveguide which may even be of the single mode optical fiber variety. As fig. 1B also shows, the radial holes 3 and cross holes 7 have narrower parts, 3B and 7B respectively, where the end of the optical guide is located and parts of wider diameter, 3A and 7A respectively, in which the lenses are located. The diameter of these wider parts is usually from two to five millimetres, while the diameter of the narrower parts is equal to or slightly wider than that of the optical guide they contain. The radial holes 3 and cross hole's 7 may also have small discs 90 of a transparent material such as organic glass which protect the lenses while reducing the accumulation of dust and grime. In other versions, the interior of the lock keyhole 16 and the exterior of the key-identifier 2 may be coated with a high-durability material, such as plexiglass or lucite, which is transparent to the radiation emitted by the source of light 6 but coloured to prevent the location of the radial holes 3 and cross holes 7 from being visible to the naked eye. This material would also replace the discs 90 in their protective function of the optical guide ends or the lenses. A filler material 88 may also be used in certain cases to fill the empty space in the interior of the key-identifier and to hold the optical guides in place. The lock cylinder: Figs. 2A, 2B and 2C shows respectively a frontal view, cross section and longitudinal section of a possible lock cylinder 24 for the present lock. The lock cylinder 24 illustrated has an octagonal keyhole 16 incorporating a retractable shutter 21 which conceals the lock cylinder when the key 25 is not inserted. Pin tumblers 18 are located in the interior of perforations 17 and 17B (of the lock cylinder and shutter respectively) to prevent the dislocation of the shutter 21 by the action of objects other than the key 25. The shutter also incorporates a slot into which the tip 29 of the key 25 is inserted. Thus the key is inserted in two different stages. First its tip 29 is inserted into the shutter 21 slot; if the contoured edge or indentations of various depth of the key are correct, the pin tumblers 18 will align and allow the shutter 21 to slide back. In the second stage the key is inserted further, which forces the shutter to retract further, activating the switch or microswitch 22 and allowing the key-identifier of the key to be fully inserted into the lock-identifier. The switch or microswitch 22 then activates the optoelectronic circuit and the key is identified. To ensure that the key-identifier 2 is in the correct position relative to the lock-. identifier 1 when the optical reading of the key takes place, the lock cylinders 24 in the present invention also incorporate means which holds the key in place after it is inserted. In the present example this mechanism is the lever 100 of the microswitch 22 which has an appropriate shape and with two chamfers, 101 and 102, which clicks into place in a recess 103 in the shutter 21 when the key 25 is properly inserted. This recess has sloping extremities 104 and 105 which, together with the lever 100, permit the shutter 21 - and therefore the key 25 - to be removably held in place. When the key is removed the shutter is then moved to the initial position for the action of the helicoidal steel spring 23. The output of the optical guides cables 11 leading from the lock-identifier is the gland 13, which in certain versions is replaced by one or two suitable optical fiber connectors which permit their semi-permanent connection with the cable or cables connected to the optoelectronic module 12 and to the optical guides collector(s) 9. The lock cylinder illustrated has a number N p of possible positions for the cross holes 7 of 7 x 6 = 42. With keys fitted with key-identifiers 2 of nine radial holes 3, the possible combinations are 42 C 9 = 4.46 x 10 8 . This means that 446 million keys can be made for this lock; the number N 2 of cross holes 7 could, for example, be eighteen. Description of the key: A key suited to the lock cylinder described above is shown in figs. 3A and 3B. Fig. 3A shows a top view of the key, while fig. 3B shows a longitudinal section. As can be seen, this key also incorporates the source of light 6, and thus in addition to the key-identifier 2 and the tip 29 for opening the shutter 21 it also contains the lenses 5, a source of electrical energy 26 (e.g. a small electrical cell) for the source of light 6 and a microswitch 28 which activates the latter when the key is inserted in the lock. The optical guides collector: The optical guides collector 9 can be fitted in a number of ways. The simplest way is obviously to collect the ends of all the optical guides 8 connected to its inputs in one bundle and locate the end of the latter in such a way that the radiation proceeding from it focuses, directly or via one or more lenses, on the photosensitive surface of a photodetector 10 incorporated in the optical guides collector 9. Alternatively, lenses can be employed to refract in parallel beams the radiation leaving each of these optical guides and to focus this collimated radiation on the tip of a single optical guide or on the said photodetector 10, as illustrated in fig. 5. A third approach is to use a certain number of optical fiber couplers of the combiner type, to combine on the output optical guide the electromagnetic radiation proceeding from the input optical guides. These optical couplers can be built by any of the better-known optical fiber techniques such as employing micro graded-index lenses as shown in fig. 4 or optical waveguide couplers. The optoelectronic module: As we have already seen, the optoelectronic module is an optoelectronic circuit which usually incorporates the photodetectors 10 and, in certain cases, the optical guides collector(s) 9. It analyses the signals generated by the photodetectors to determine whether the key inserted is the correct one or not. If the key is the correct one, and in the existence of certain pre-established conditions, one or more functions are activated via its output, such as an electromagnetic relay which in turn activates an electric latch or an electric lock, where the present optoelectronic lock protects a certain space. One of the pre-established conditions mentioned above might be that the limit for consecutive insertion of incorrect keys has not been reached. Another might be that after the insertion and analysis of an incorrect key, this must be withdrawn for the optoelectronic module to proceed to a next optical reading. The inclusion of these two conditions - or at least the second - is extremely convenient to prevent the use of a key specially designed to exhaust the millions of possible combinations. An optoelectronic circuit suited to the module in question is perfectly commonplace and therefore does not require description. Variations: A vast number of variations to the embodiments outlined above exist. Some of these are described below. Variation A: Here, when the correct key 25 is inserted the photodetector 10 connected to the output of the optical guides collector 9 is not activated, while the set of photodetectors 10 (activated and non-activated) connected via optical guides 8 to the lock-identifier 1 form a pre-defined sequence. Variation B: In this variation the source of light 6 is located in the key 25 and emits a modulated radiation, said modulation being a code which can vary from lock to lock - and among different keys for the same lock - allowing in the latter case, the lock to recognise and differentiate between the different keys which can activate it and the different functions to be activated. For this purpose its optoelectronic module 12 is fitted with a special electronic circuit. This modulation can be obtained either via the modulation of the. electric signal which feeds the source of light 6 or via the use of an optical or electro-optical modulator located (usually) in the key between the source of light 6 and the lens or lenses 5. Variation C: The use of optical guides in the lock of the present invention makes it possible to dispense the keyhole 16. This may be a major advantage, since it is often the keyhole which is the most vulnerable part of a lock. Figs. 6A and 6B show the longitudinal section of a suggested lock cylinder 24 of this variation and a longitudinal section of the corresponding key 25. When the key is inserted or fitted into the lock cylinder 24, the contact surface between its key-identifier 2 and the lock-identifier 1 is a flat one, i.e. contact occurs entirely on the same plane. Both the lock-identifier I and key-identifier 2 of this variation have a set of perforations - 96 and 97 respectively - which are perpendicular to the plane of contact and correspond to the cross holes 7 and radial holes 3 of the versions of the present optoelectronic lock which include a keyhole 16. In a similar way to the other versions, perforations 96 and 97 each contain respectively the tip of an optical guide 8 and part of an optical guide 83 and sometimes - as in the example illustrated - lenses 87 and 86. In the present example, the source of light 6 is located in the optoelectronic module 12, with the radiation transmitted to the lock cylinder 24 by the optical guide 73. When the key 25 is inserted or fitted, the radiation is transmitted by the graded-index rod lens 91 to the star-type optical coupler 92 and is then divided among the optical guides 83 connected to its outputs. These transmit the signal to the lenses 86 (in the case, also graded-index rod lens), from where it is transferred to the matching lenses 87 and from there to the corresponding optical guides 8. In this variation, both the lock cylinder 24 and the key 25 incorporate a plaque 71 and 81 respectively made of a high-durability material, such as plexiglass, lucite, or even sapphire, which is transparent to the radiation emitted by the source of electromagnetic radiation 6 but coloured in such a way as to prevent the location of tips of the optical guides 8 and 83 - or the lenses 86 and 87, depending on the case - from being seen. They also offer physical protection for the lock-identifier 1 and key-identifier 2. The key 25 has two nibs 93 which fit into corresponding grooves 94 in the lock cylinder 24 to ensure that the key is inserted properly. Figs. 7A and 7B show frontal views of the lock cylinder and key respectively. The lock cylinder 24 used in any versions and/or variants may also contain a physical integrity testing system consisting of a conductive segment or track which crosses the interior of the lock cylinder and breaks if the lock cylinder is subject to abusive or violent attempts to access its interior and/or to unlock the lock. This segment or track is connected electrically to the optoelectronic module 12. Its breakage informs the optoelectronic module of the attempts to gain illegitimate access and the lock becomes blocked for an indeterminate period.

Claims: Optoelectronic locking system comprising a key, means (1) for optical recognition of said key, one or more light sources (6), one or more light-current transducers (10) and an electronic module (12) which analyses the electrical signals produced by said light-current transducers (10) and activates one or more desired functions when the correct key is inserted into or adapted to said means (1), characterised by : said one or more light-current transducers (10) and said electronic module (12) being remotely placed from said means (1) for optical recognition of the key, meaning that they are placed in a location other than the location where said means (1) is placed; wherein the communication between said means (1) for optical recognition of the key and said one or more remote light-current transducers (10) is made entirely by optical means (8); wherein said means (1) for optical recognition of the key has no electrical or electronic components except possibly one switch or micro-switch (22) for powering on and off said electronic module (12) and no electrical wires except possibly the corresponding two electrical wires for said switch or micro-switch (22). Optoelectronic locking system as described in claim 1, characterized by said optical means (8) being composed by one or more optical guides (8) each of which comprising one or more optical fibers. Optoelectronic locking system as described in claim 1, characterised by having means (9) which have several optical inputs and only one output and which combine in said single output the light radiation proceeding from its several optical inputs, said means (9) which we shall designate as the combiner (9). Optoelectronic locking system as described in claim 3, characterised by said output of said means (9) being connected to one of said light-current transducers (10) by means of one optical guide (8) made of one or more optical fibers. Optoelectronic locking system as described in claim 3, characterised by said output of said means (9) being adapted to one of said light-current transducers (10). Optoelectronic locking system as described in claims 2 or 3, characterised by said several optical inputs, each being connected or adapted to one end of an optical guide (8), other end of said optical guide (8) being connected or adapted to said means (1) for optical recognition of the key. Optoelectronic locking system as described in claim 6, characterised by each said several optical inputs having means for connecting it or adapting it to one end of an optical guide (8). Optoelectronic locking system as described in claims 1, 2 or 3, characterised by said means (1) for optical recognition of the key having one or more perforations (7) each of which has inside one end of one said optical means (8), the other end of said optical means (8) being connected or adapted to one said remote light-current transducers (10) or to one of the inputs of said combiner (9). Optoelectronic locking system as described in claim 1, characterised by said key having: format and dimensions enabling its insertion or adaptation to said means (1) for optical recognition of the key; one or more perforations (3) each of which contain one end of an optical guide (83); further characterised by said one or more perforations (3) being in such a position that they all coincide, when the key is properly inserted or adapted or placed in said means (1) for its optical recognition, for which said key was made, with some of the perforations (7) of said means (1). Optoelectronic locking system as described in claim 9, characterised by each optical guide (83) being made of one optical waveguide or by one or more optical fibers, further characterised by the other end of each said optical guides (83) being connected or adapted to optical or electro-optical means (91, 92) for receiving and transmitting to said end the light from said one or more light-sources (6), when said key is properly inserted or adapted or placed into said means (1) for its optical recognition. Optoelectronic locking system as described in claims 1, 8 or 9, characterised by having optical means (87) inside each of said perforations (7) of said means (1) for optical recognition of the key and by having also optical means (86) inside each of said perforations (3) of said key, further characterised by each of said optical means (86) in conjunction with the corresponding optical means (87) enabling the efficient optical coupling of the light from the emitting tip of its optical guide (83) to the receiving tip of the corresponding optical guide (8). Optoelectronic locking system as described in claim 11, characterised by each of said optical means (87) inside said perforations (7) being connected or adapted to the corresponding optical guide (8). Optoelectronic locking system as described in claim 11, characterised by each of said optical means (86) inside said perforations (3) being connected or adapted to the corresponding optical guide (83). Optoelectronic locking system as described in claim 11, characterised by said optical means (86, 87) placed inside said perforations (3,7) being one ore more lenses. Optoelectronic locking system as described in claim 11, characterised by said opticat means (86, 87) placed inside said perforations (3, 7) being one ore more graded-index rod lenses. Optoelectronic locking system as described in claims 1, 3, 8 or 9, characterised by all the perforations (7) which must not coincide with any perforation (3) of the correct key being each connected or adapted by means of an optical guide (8) to one of the optical inputs of said combiner (9). Optoelectronic locking system as described in any preceding claim, characterised by said one or more light-sources (6) being placed in said remote electronic module (12) or in anywhere else and the emitted light being transmitted to said means (1) for optical recognition of the key by means of an optical guide (8) comprising one or more optical fibers; further characterised by said means (1) incorporating optical means (91) which transmit to the key, when said key is inserted or adapted or placed in said means (1), the light emitted by said one or more light-sources (6). Optoelectronic locking system as described in any preceding claim, characterised by said key incorporating an electronic modulator which modulates and codify the radiation emitted by said one or more light-sources (6), with a modulation or code which is different from lock to lock, said modulation or code being also used to identify the correct key. Optoelectronic locking system as described in any preceding claim, characterised by said key incorporating an electro-optical modulator, which modulates and codify the radiation emitted by said one or more light-sources (6), with a modulation or code which is different from lock to lock, said modulation or code being also used to identify the correct key. Optoelectronic locking system as described in claim 1, characterised by said means (1) for optical recognition of the key having physical integrity testing means consisting of a conductive segment or track located inside said means (1) and electrically connected to said electronic module (12), which inform the latter, by breaking of the circuit, of abusive or violent attempts to activate or unlock the locking system or to gain illegitimate access. Optoelectronic locking system as described in claim 1, characterised by said means (1) for optical recognition of the key having physical integrity testing means consisting of an optical segment, track or optical guide located inside means (1) and adapted to receive on one of its ends, light from said one or more light-sources (6) and with its other end connected or adapted to one of said light-current transducers (10), informing said electronic module (12) by breaking of the optical circuit, of abusive or violent attempts to activate or unlock the locking system or to gain illegitimate access.

Inventors: NEVES DOS SANTOS PAULO JOAQUIM, NEVES DOS SANTOS, PAULO JOAQUIM
Applicants: NEVES DOS SANTOS PAULO JOAQUIM, NEVES DOS SANTOS, PAULO JOAQUIM
Application year: 1997
Main classification: E05B49
IPC codes: G07C9