JP2008038382A - Optical key and optical key system using the same - Google Patents

Abstract

An inexpensive optical key with high security and an optical key system using the same are provided.
In an optical key, an optical filter group consisting of a plurality of optical filters is disposed on a light-shielding substrate part. These optical filters 13 a are fitted into the guide holes 16 a, 16 b, and 16 c together with the cover member by the slider 14, and the arrangement position is changed by sliding the slider 14. Openings 17 are respectively provided in the regions where the respective optical filters 13a are provided, and the irradiation light can be transmitted through the respective optical filters 13a to detect the respective light transmission characteristics. The optical key system is configured to optically / electronically read key information including the position of the optical filter 13a in the optical key 10 and its light transmission characteristics, and to perform authentication determination of the optical key. ing.
[Selection] Figure 1

Description

  The present invention relates to an authentication technique for unlocking or locking, and particularly to an inexpensive and highly secure optical key using an optical member and an optical key system using the same.

  In an entrance / exit key (lock) system in a house, a room, a vehicle, or the like, an electronic key or an optical key has been proposed in place of a mechanical key that is widely used at present. This is because, for example, security locks with higher security are required due to worsening security such as picking theft, and further, security awareness has been further improved.

  In general, mechanical keys and cylinder locks that are often used in the past use a key obtained by carving a unique shape into a small piece of metal, and authenticate the key by physically contacting the uniqueness of the key. If it is determined that the authentication is correct, unlocking / locking is performed. Alternatively, it is determined whether or not the key is appropriate by electrically connecting the electrical contacts between the key and the lock and reading the combination. However, in such a mechanical key system, wear of the lock and deterioration of continuity cannot be avoided as the number of uses increases. Also, copying by a third party is relatively easy.

  Therefore, for example, an electronic key system has been proposed in which a metal piece is provided with a shape to be used as a determination criterion such as a punch hole or a notch, and light is irradiated to read the shape (see, for example, Patent Document 1). ). In the shape reading method using the light irradiation, the wear of each member is reduced as compared with the mechanical type. However, in this method, the number of the shapes provided on the metal piece is limited, and it is difficult to increase the number of key differences. And since the duplication is relatively easy as in the case of the mechanical key, it is difficult to improve the security.

As a method for improving the security of the key, there is an optical key system that performs authentication using a transmitted light spectrum or a reflected light spectrum inherent to an optical member formed with a multilayer thin film instead of the shape provided on the metal piece. It has been proposed (see, for example, Patent Documents 2 and 3). In this case, a single dielectric layer having a thickness of about 100 nm is laminated on a single transparent substrate in multiple layers, for example, 20 to 100 layers. One optical member formed with the multilayer thin film serves as an optical key. In this method, it is very difficult to duplicate an optical key in which a multilayer thin film is formed with the same refractive index, film thickness, lamination, etc. of the dielectric layer. For this reason, the security is remarkably improved.
However, this optical key becomes an optical member having a complicated and elaborate structure, and the productivity is extremely low because it is produced as a single product. Also, for example, it becomes difficult to reproduce the same item when the key is lost. For these reasons, such an optical key is inevitably expensive. In addition, due to the above-described sophisticated multilayer film structure, an authentication error is likely to occur due to a change in the environmental temperature of the key system. This is because the spectral characteristics of the optical key are easily affected by expansion and contraction accompanying the temperature change of the multilayer dielectric layer.

Furthermore, as a key system that enhances security, a key system that uses an authentication technique that is fundamentally different from the conventional key concept and discriminates based on individual biometric information such as fingerprints, voices, faces, eyes, etc. (For example, see Patent Document 4). In such a biometric key system, an extremely high degree of statistical coincidence is essential for authentication. However, at present, it cannot be said that the reading of biological information is sufficiently stable, and there is a need for further improvement in sensing accuracy of biological information.
No. 05-6362 JP 2000-220331 A JP 2006-97426 A JP 2004-353418 A

  The present invention has been made in view of the circumstances as described above, and the purpose of the present invention is to ensure high security easily, and to have high productivity and to reduce its cost. An object of the present invention is to provide an optical key that can easily cope with loss of a key, has high convenience, and has high practicality, and an optical key system using the optical key.

  In order to achieve the above object, in the optical key according to the first invention, a plurality of optical filters having different light transmission characteristics are arranged on the key substrate surface, and the light transmission characteristics of each optical filter read by the irradiation light are used. Key information is configured. Further, by adding information on the arrangement position on the key board surface, higher security can be secured.

  In the optical key system according to the second aspect of the present invention, a plurality of optical filters having different light transmission characteristics are arranged on the key substrate surface, and the light transmission characteristics of each optical filter read by the irradiation light constitute key information. An optical key, a light source of the irradiation light, a key information storage means storing an optical filter arrangement position and a light transmission characteristic for determination criteria, and an arrangement of the optical filter on the key substrate surface. Filter position detection means for detecting the installation position, filter information reading means for reading the light transmission characteristics of the optical filter, detection position of the optical filter detected by the filter position detection means, and detection by the filter information reading means The optical transmission characteristics of the optical filter and the position of the optical filter stored in the key information storage means. Collating the light transmission characteristics for fine criterion has a structure having an authentication determining means for determining the identity of it like.

  According to the present invention, an inexpensive and highly secure optical key and an optical key system using the same are easily provided. The optical key and optical key system have high convenience and high practicality.

  Preferred embodiments of the present invention will be described below with reference to the drawings. In the drawings, the same or similar parts are denoted by common reference numerals, and redundant description is omitted.

  First, the optical key will be described with reference to FIGS. Here, FIG. 1 is a plan view showing an example of an optical key. 2 is a cross-sectional view taken along arrows XX and YY in FIG. FIG. 3 is a diagram showing an example of light transmission characteristics of the optical filter of the optical key.

  As shown in FIG. 1, the optical key 10 of this embodiment has a flat plate-like substrate portion 11 that is a light-shielding aluminum key substrate and a plastic gripping portion 12, for example. A plurality of optical filters 13 a are arranged on the substrate unit 11 as an optical filter group 13. In FIG. 1, the optical filter group 13 is composed of 30 optical filters 13a arranged in a matrix of 3 rows and 10 columns on the plane of the substrate. The number of optical filters 13a or the arrangement pattern thereof is as follows. It is not limited to what is shown in FIG. Here, the planar shape of the optical filter 13a is preferably rectangular. These optical filters 13a are housed in the respective frames of, for example, a resin slider 14 configured in a frame shape. The substrate portion 11 can take other shapes such as a card or a cylinder.

  As shown in FIGS. 2A and 2B, a large number of optical filters 13 a in the optical filter group 13 are sandwiched from above and below together with the slider 14 by two transparent cover members 15, and are provided on the substrate unit 11. The holes 16a, 16b and 16c are inserted. And the opening 17 is provided in the upper surface and lower surface of the board | substrate part 11 of the area | region in which each optical filter 13a is arrange | positioned, and irradiation light from the upper surface side passes through these opening 17 and each filter 13a, and the lower surface side Can be emitted. Here, the guide holes 16a, 16b, and 16c have a cross-sectional shape of, for example, a rectangle, and the opening 17 has a planar shape of, for example, a circle or a rectangle.

  For the guide holes 16a, 16b, and 16c, for example, two thin plates made of aluminum are provided with grooves extending in the row direction, and the two thin plates are positioned and bonded so that these grooves face each other. Thus, the substrate portion 11 is easily formed. The opening 17 is formed by punching a predetermined region of the groove of the two thin plates.

  Further, the slider 14 accommodating the optical filter 13a can be slid freely in the row direction in the guide holes 16a, 16b and 16c, and the arrangement position of the optical filter 13a in the row direction can be changed by the sliding movement. It has become. Here, the cover member 15 is made of, for example, transparent plastic, and the user can change the combination appropriately by fixing the optical filter 13a in the guide holes 16a, 16b, and 16c. Yes.

  Reference holes 18a, 18b, and 18c are provided through the substrate portion 11 from the upper surface to the lower surface in the tip regions of the guide holes 16a, 16b, and 16c, respectively. Here, the reference holes 18a, 18b, and 18c may be formed in any shape such as a circular shape or a rectangular shape.

  The optical filter 13a constituting the optical filter group 13 of the optical key 10 has various light transmission characteristics as shown in FIG. 3 in a wavelength region from infrared rays to ultraviolet rays. A typical example of light transmission characteristics will be described below. For example, FIG. 3A shows the light transmission characteristics of a single wavelength pass filter, which is a case of an optical filter having a predetermined half-value width (for example, about 15 nm) and transmitting light of a specific wavelength. Here, it is possible to form single wavelength pass filters having different center wavelengths and half widths.

  FIG. 3B shows the light transmission characteristics of a band-pass filter having a relatively wide transmission wavelength width as compared with FIG. 3A, and is a case of an optical filter that transmits light in a certain wavelength band. Also in this case, bandpass filters having different wavelength bands can be formed.

  FIG. 3C shows the light transmission characteristics of the multi-wavelength pass filter, and is a case of an optical filter that transmits light of a plurality of specific wavelengths. Although the figure shows a case where two specific wavelength lights are transmitted, an optical filter that transmits three or more specific wavelength lights may be used. Also in this case, it is possible to form a multiple wavelength pass filter in which light of a specific wavelength is different.

  FIG. 3D shows the light transmission characteristics of a long wavelength pass filter (long wave pass filter), and is a case of an optical filter that transmits light having a wavelength longer than a predetermined wavelength. Also in this case, it is possible to form long wavelength pass filters having different predetermined wavelengths.

  FIG. 3E shows the light transmission characteristics of a short wavelength pass filter (short wave pass filter), which is an optical filter that transmits light having a wavelength shorter than a predetermined wavelength. Also in this case, short wavelength pass filters having different predetermined wavelengths can be formed.

  The optical filter 13a is preferably an optical interference filter, for example, formed by laminating a plurality of dielectric layers on the surface of a transparent glass substrate. Here, a dielectric layer having various refractive indexes is used. Such an interference filter has a very simple structure, unlike the case of multilayer thin film formation in which a dielectric layer is laminated on, for example, 20 to 100 layers described in the prior art and has a complicated and elaborate structure. For this reason, a large number of optical filters 13a having light transmission characteristics that can be regarded as substantially the same can be mass-produced. Here, the light transmission characteristics that can be regarded as substantially the same will be explained in the key determination criteria described later. Even if this optical interference filter cannot be distinguished visually, various filters having different light transmission characteristics can be manufactured, which is advantageous as a means for holding key information.

  As a feature of the optical key 10 of the present embodiment, a plurality of optical filters 13a having the above-described light transmission characteristics are appropriately arranged in combination on the substrate portion 11 to form an optical filter group 13.

  For example, assuming that an optical filter in the visible light band of 440 nm to 700 nm is formed, eleven types of single wavelength pass filters shown in FIG. When one type of each of the pass filters of FIGS. 3B to 3E is produced, there are a total of 15 types of optical filters having different light transmission characteristics. If the total of 15 types of optical filters 13 a are arranged in, for example, 3 rows and 10 columns shown in FIG. 1, optical filter groups 13 having the number of combinations of 15 to the 30th power can be formed. The number of key differences of the key 10 is a huge number about 1 trillion times 1 trillion times 1 trillion. Here, the case where the optical filter group 13 includes the optical filter 13a having the same light transmission characteristic is also included.

  Thus, the optical key 10 of the present embodiment can increase the number of key differences to an enormous number very easily, and can easily ensure its high security. Further, since each optical filter used in the optical key 10 can be reproduced in large quantities, an inexpensive and convenient optical key is realized.

  Next, an optical key system using the optical key as described above will be described with reference to FIGS. Here, FIG. 4 is a side sectional view showing an example of the optical key system. FIG. 5 is a light emission spectrum diagram showing an example of irradiation light applied to the optical filter 13a, and FIG. 6 is a functional block diagram showing a main functional configuration of the optical key system.

  As shown in FIG. 4, the optical key system 20 is provided with an insertion hole 22 for inserting, for example, the optical key 10 on the front side of the authentication chamber 21, and above the insertion hole 22 in the authentication chamber 21. For example, an irradiation light source 23 composed of a white LED (Light Emitting Diode) is attached. Between the irradiation light source 23 and the insertion hole 22, a diaphragm hole plate 25a having a diaphragm hole 25 for narrowing and collimating the light beam of the irradiation light 24 from the irradiation light source 23 is fixedly disposed. Here, the white light emitted from the white LED as the irradiation light source 23 has a light spectrum in the visible region with a wavelength of 400 nm to 750 nm as shown in FIG. 5, for example.

  A so-called optical spectrum analyzer including a reflective grating 26 and a line sensor 27 is disposed below the insertion hole 22 in the authentication chamber 21. Here, the grating 26 reflects light incident from above. Then, the first-order diffracted light is dispersed as a spectrum in order of wavelength, and is photoelectrically converted by a line sensor 27 made of, for example, a solid-state image pickup device such as a CCD or CMOS, and converted into an electrical signal corresponding to the light intensity. As taken out. Although the details will be described later, a determination unit 28 that processes an electrical signal from the line sensor 27 and authenticates the optical key 10 is attached below the line sensor 27.

  Here, for example, urethane resin grip rollers 29 a and 29 b are formed in the insertion hole 22, and the optical key 10 can be smoothly inserted into the authentication chamber 21 by the rotation of the grip rollers 29 a and 29 b. It is like that. Although the details of the grip rollers 29a and 29b will be described later, the grip rollers 29a and 29b function as a rotary encoder by their rotation. Then, the column direction position of the optical filter 13 a disposed on the substrate portion 11 of the optical key 10 is detected. Moreover, the irradiation light source 23 is turned on and light irradiation is performed with the start of the rotation operation of the grip rollers 29a and 29b. Specific examples of these will be described later in the preferred usage of the optical key system.

  Although not shown, it is preferable that a cleaning mechanism for cleaning the surface of the substrate portion 11 of the optical key 10 with a brush, for example, is fitted on the side wall of the insertion hole 22.

  Alternatively, a position sensor may be attached inside the authentication chamber 21. This position sensor detects a predetermined marking (not shown) on the upper surface of the substrate part 11 in the optical key 10 inserted into the insertion hole 22, and a signal for turning on the irradiation light source 23 or the position in the row direction of the rotary encoder. Generate a signal that determines the starting point of.

  In the optical key system 20, the same number of irradiation light sources 23, diaphragm hole plates 25 a, gratings 26 and line sensors 27 as the number of rows of the matrix arrangement of the optical filter group 13 on the surface of the substrate portion 11 of the optical key 10 are provided. The Here, in the example of the optical key 10 described with reference to FIGS. 1 and 2, three units each including the irradiation light source 23, the aperture hole plate 25a, the grating 26, and the line sensor 27 are attached.

  The main functional configuration of the optical key system 20 is as shown in FIG. That is, the optical key system 20 includes an irradiation light source 23, an optical key 10, a filter information reading unit 31, an irradiation light spectrum reading unit 32, and a filter position detection unit 33. Further, the optical key system 20 includes a data temporary storage unit 34 that temporarily stores signal data generated by the filter information reading unit 31 or the irradiation light spectrum reading unit 32. A filter information calibration unit 35 that normalizes and corrects the signal data from the filter information reading unit 31 is provided. Further, a CPU 36 that performs key authentication determination using the standardized filter information from the filter information calibration unit 35, a determination reference data memory unit 37 that stores a determination reference, and a filter information memory unit 38 are provided.

  In the above functional configuration, the irradiation light source 23 exposes filter information that is optical information integrated in the optical filter group 13 of the optical key 10. Here, the irradiation light source 23 only needs to emit light in a predetermined wavelength band. The infrared light band or the ultraviolet light band may be basically used. However, since it is easy to obtain a member in the visible light band, a white light source such as a white LED is suitable as described with reference to FIGS.

  Specifically, the filter information reading unit 31 is an optical spectrum analyzer that includes the aperture plate 25a, the grating 26, and the line sensor 27 described in FIG. The grating 26 is a reflection type diffraction grating, but may be a transmission type diffraction grating. The filter information reading unit 31 reads out filter information as key information of the optical filter group 13 incorporated in the optical key 10 as an electric signal.

  Similarly, the irradiation light spectrum reading unit 32 includes the aperture plate 25a, the grating 26, and the line sensor 27 as described with reference to FIG. The irradiation light spectrum reading unit 32 reads the optical spectrum of the irradiation light emitted from the irradiation light source 23 and transmitted through the reference hole 18 provided in the substrate portion 11 of the optical key 10 as an electrical signal.

  The filter position detection unit 33 determines the filter position of each optical filter 13a in the optical filter group 13 disposed on the substrate unit 11 of the optical key 10, for example, the column direction and row direction positions of the matrix arrangement of the optical filter group 13. To detect. Specifically, the rotary encoder described in FIG. 4 detects the column direction position of the matrix array. The position of the matrix array in the row direction is determined by a unit including the irradiation light source 23, the aperture plate 25a, the grating 26, and the line sensor 27 described above. The filter position detector 33 can have other configurations. Other examples will be described later with reference to FIG.

  The temporary data storage unit 34 stores the filter information signal data and the irradiation light spectrum signal data detected by the line sensor 27. Here, the data temporary storage unit 34 can store all the filter information of the optical filter group 13 of the optical key 10 by linking to the positional information of each optical filter 13a from the filter position detecting unit 33. ing.

  The filter information calibration unit 35 standardizes and calibrates the filter information signal data of each optical filter 13a based on the signal data of the irradiation light spectrum. That is, after the spectrum with the optical spectrum analyzer, the intensity of the transmitted light of each optical filter 13a is normalized by the intensity of the irradiation light for each wavelength. Specifically, the spectrum signal of the irradiation light from the line sensor 27 and the spectrum signal of the transmitted light of each optical filter 13a are respectively transferred to the arithmetic circuit through the multiplexer, and the spectrum signal of the filter transmitted light is irradiated for each wavelength. Calculation (for example, division) is performed on the spectrum signal of light. Then, the division signal (calibration signal) generated by the division process over all the optical filters 13a of the optical filter group 13 in the optical key 10 is transmitted to the CPU 36 as filter information together with the arrangement position.

  The CPU 36 controls the drive of the filter information calibration unit 35 and performs authentication determination of the optical key 10 based on the calibration filter information including the calibration signal. Here, the reference filter information is read out from the determination reference data memory unit 37 in which the filter information of the determination reference related to the optical filter group 13 of the optical key 10 is stored, and is compared / verified with the calibration filter information. The The CPU 36 is preferably made of a microprocessor or the like because it is downsized.

  Here, the criterion data memory unit 37 stores criterion filter information data serving as a criterion for authentication determination. That is, filter information such as an allowable range indicating the same light transmission characteristic in each optical filter 13a and an arrangement position of each optical filter 13a on the key substrate surface is stored.

  In the comparison / collation, when it is determined that the reference filter information data and the calibration filter information data are the same, the CPU 36 transmits an unlocking electric signal to the electromagnetic lock to release the lock. The calibration filter information data is preferably stored in the filter information memory unit 38. On the other hand, if it is determined that they are not the same, the unlocking operation is not performed.

  Here, the determination criterion of the identity in the comparison / collation is determined in consideration of the wavelength resolution and temperature dependency of the optical spectrum analyzer described above, the temperature dependency of the light transmission characteristic in the optical filter 13a, and the manufacturing accuracy. For example, when the optical filter 13a is formed of an interference filter for visible light, the allowable range of the identity is ± 10 nm at the spectral wavelength, and the transmittance may be ± 20%. This identity criterion can be set and adjusted in software. If the optical filter 13a is not an interference filter corresponding to visible light, the determination criterion for identity is determined in consideration of reproducibility of light transmission characteristics in mass production of the optical filter 13a.

  In addition, it is preferable to determine a determination criterion that does not make an erroneous determination in consideration of temporal changes of the optical filter 13a and the line sensor 27. Here, a simple method for determining the determination standard corresponding to the change with time is to rewrite the reference filter information data in the determination reference data memory unit 37 periodically. As the reference filter information data to be rewritten, calibration filter information data stored in the filter information memory unit 38 by the user of the optical key system 20 may be periodically used. Note that the initial value of the reference filter information data stored in the determination reference data memory unit 37 is stored separately so that it can be read at any time.

  The reference filter information data is stored in the determination reference data memory unit 37 in advance by the manufacturer of the optical key system 20 based on the light transmission characteristics shown in FIG. 3 of each optical filter 13a attached to the optical key 10. May be.

  The display unit 39 basically displays the authentication determination result. The data temporary storage unit 34, the filter information calibration unit 35, the CPU 36, the determination reference data memory unit 37, the filter information memory unit 38, and the display unit 39 are housed in the determination unit 28 shown in FIG.

  Next, a modification of the optical key 10 used in the optical key system 20 will be described with reference to FIG. In the optical key 10 a, a scale hole 40 is provided along the side end portion of the substrate portion 11. This scale hole 40 constitutes a linear encoder together with its position sensor (not shown) and the like, and instead of the rotary encoder, the position in the column direction of the matrix arrangement of the optical filters 13a in the optical filter group 13 of the optical key 10a. Is detected. Here, the number of the scale holes 40 may be the same as the number of the optical filters 13a in the column direction of the matrix arrangement (10 in this embodiment), or may be a different number.

  In addition, various modifications of the optical key 10 described in the present embodiment are conceivable. For example, a structure without the reference hole 18 described with reference to FIGS. In this case, the irradiation light from the irradiation light source 23 is spectrally detected by the optical spectrum analyzer without passing through the optical key, and the signal data of the irradiation light spectrum is generated. Or the board | substrate part 11 of the optical key 10 may be comprised with the transparent material like a plastics which has a light transmittance. In this case, the irradiation light from the irradiation light source 23 can split the irradiation light transmitted through the transparent substrate portion 11 with an optical spectrum analyzer to generate signal data of the irradiation light spectrum.

  Moreover, in the optical filter group 13, it is not necessary to arrange | position each optical filter 13a continuously, and the light shielding member of the irradiation light 24 may be arrange | positioned among the some optical filters 13a. Alternatively, a transparent member for the irradiation light 24 may be provided between the plurality of optical filters 13a, and the irradiation light may pass between them.

  In addition to the optical interference filter, the optical filter 13a may be formed of an optical film having spectral transmission characteristics that are not uniform with respect to the wavelength, or a colored glass or colored film, although the security level is lowered.

  In any case, in the optical key of the present embodiment, the light transmission characteristics of the plurality of optical filters disposed on the substrate unit 11 and the positions of the optical filters disposed on the key substrate surface may be key information.

  Next, a preferred usage mode of the optical key system of this embodiment will be described with reference to FIGS. FIG. 8 is a flowchart showing an outline of the usage mode, and FIG. 9 is a side sectional view at each step when the optical key 10 is inserted in the optical key system 20, for example.

  In step S1 of FIG. 8, in order to unlock the electromagnetic lock, for example, the optical key 10 is inserted into the insertion hole 22 of the optical key system 20 as shown in FIG. Then, the grip rollers 29a and 29b are rotated and the optical key 10 is inserted into the authentication chamber 21 while being kept in a substantially horizontal state. At the same time, the cleaning mechanism attached to the side wall of the insertion hole 22 removes deposits that adhere to the substrate portion 11 of the optical key 10 and shield the irradiation light.

  In step S2, the irradiation light source 23 is turned on by starting the rotation of the grip rollers 29a and 29b, and the irradiation light 24 is irradiated from, for example, a white LED. Subsequently, the irradiation light 24 passes through the reference hole 18 of the optical key 10, and the grating 26 and the line sensor 27 perform spectroscopy and detection of the irradiation light 24 in step S3. That is, the light intensity of the spectrum of the irradiation light 24 is measured, and signal data of the irradiation light spectrum is generated. Here, after a predetermined time lag from the lighting of the irradiation light source 23, the reference hole 18 comes directly under the aperture hole 25, and the spectrum and detection of the irradiation light 24 are performed.

  Further, by starting the rotation operation of the grip rollers 29a and 29b, the starting point of the column direction position on the key board surface in, for example, a photoelectric or magnetic rotary encoder interlocking with the rotation of the grip rollers 29a and 29b is determined.

  In step S4 of FIG. 8, the optical key 10 is further inserted into the authentication chamber 21, and each optical filter 13a of the optical filter group 13 is irradiated with the irradiation light 24, and the transmitted light is split and detected. The That is, the light transmission characteristic of each optical filter 13a is measured, and signal data of filter information is generated. FIGS. 9C and 9D show examples of states in which the filter light is split and detected. In this way, the filter information of all the optical filters 13a in the optical filter group 13 is read out as electrical signals. At the same time, the position of the optical filter 13a in the row direction on the key substrate surface is detected by a rotary encoder that is interlocked with the rotation of the grip rollers 29a and 29b.

  Alternatively, in the case where the position sensor is attached above the insertion hole 22 outside the authentication chamber 21 described above in the description of FIG. 4, the position sensor is a substrate portion in the optical key 10 inserted into the insertion hole 22. A predetermined marking (not shown) on the upper surface of 11 is detected. A signal for turning on the irradiation light source 23 or a signal for determining the starting point of the row direction position in the rotary encoder is generated by the detection of the position sensor. Based on the detection signal from the position sensor, the starting point of the rotary encoder is accurately determined, and the precise arrangement position of the optical filter 13a on the key substrate surface of the optical key 10 can be detected.

  After that, as shown in FIG. 9E, the optical key 10 is stopped from being inserted into the authentication chamber 21 by the grip portion 12, and the irradiation light source 23 is turned off.

  In step S5 in FIG. 8, these filter information data are normalized / corrected by the filter information calibration unit 35 described with reference to FIG. 6 and processed into calibration filter information.

  Then, in step S6 of FIG. 8, the CPU 36 compares / collates the reference filter information data of the optical key 10 stored in the determination reference data memory unit 37 with the calibration filter information as described in FIG. The authentication determination of the optical key 10 is performed.

  In this comparison / collation, an authentication determination is made as to whether the reference filter information data and the calibration filter information data are the same. If it is the same determination, for example, the electromagnetic lock is unlocked in step S7, and the series of processing ends. On the other hand, if the determinations are not the same, the key is invalid in step S8 and unlocking is not performed. These determination results are displayed on the display unit 39 shown in FIG.

  Then, the optical key 10 is taken out from the authentication chamber 21 through the insertion hole 22. Here, after the filter information of the optical key 10 is read, it can be taken out even before the determination result is displayed. In the locking, the electromagnetic lock is normally locked by a simple switch operation, but it may be performed similarly to the unlocking using the optical key system.

  In the optical key of this embodiment, as described above, a plurality of optical filters are arranged on the key substrate and arranged as an optical filter group. Here, this optical filter has a simple structure like an interference filter and can be mass-produced with the same transmission characteristics. An optical key in which such an optical filter is arranged enables a large number of key differences by a few types of optical filters. For this reason, imitation or duplication by another person of the optical key is very difficult as in the case of Patent Documents 2 and 3. Thus, an optical key having extremely high security is realized.

  In addition, with this optical key, optical filters with the same light transmission characteristics can be mass-produced, and the plurality of optical filters are combined and disposed on the key board, so the cost of the optical key can be easily reduced. become. Moreover, since the optical filter can be easily reproduced, its convenience is improved, and the practicality of the optical key becomes extremely high.

  In the optical key system of the present embodiment, as described above, the irradiation light is transmitted through the optical filter arranged in the optical key, and the position information of the arrangement is transmitted along with all the optical filters of the optical filter group. The filter information it has is read out. Then, the filter information data undergoes appropriate processing such as calibration, and is compared / verified with the reference filter information data stored and stored in the optical key system, and authentication determination of the identity is made. Here, as described above, the structure of the optical filter of the optical key is extremely simple, and the temperature variation of the light transmission characteristics of the optical filter is small. For this reason, the occurrence of an erroneous determination due to a change in environmental temperature or the like is greatly reduced as compared with the conventional technique described above.

  Further, in the optical key system of this embodiment, for example, when the key is lost, it is easy to reproduce the same one, and key management can be simplified. In addition, the optical / electronic reading mechanism of the key information of the optical key can be extremely simplified, and the optical key system can be realized with a small size and at a low cost. Further, since the optical key having different filter information can be quickly and easily manufactured with high security even in the case of theft of the key, the convenience of the key system is improved as compared with the prior art.

  Although the preferred embodiments of the present invention have been described above, the above-described embodiments do not limit the present invention. Those skilled in the art can make various modifications and changes in specific embodiments without departing from the technical idea and technical scope of the present invention.

  For example, in the above embodiment, the light transmission characteristic of the optical filter of the optical key is calibrated by the irradiation light. However, for example, when a white LED having a constant emission spectrum is used as the irradiation light source, there is no calibration means. It may be an optical key system.

  Further, the filter information reading means for reading the light transmission characteristics of the optical filter of the present embodiment generates an electric signal by the spectrum of the transmitted light and the photoelectric conversion, but the optical transmission of the optical filter that does not convert the electric signal. A characteristic reading method may be used.

It is a top view which shows an example of the optical key concerning embodiment of this invention. It is a figure of the cross-sectional structure of the said optical key, Comprising: (a) is sectional drawing of XX arrow of FIG. 1, (b) is sectional drawing of YY arrow of the figure. It is the figure which showed an example of the light transmission characteristic which the optical filter of the optical key concerning embodiment of this invention has. It is a sectional side view which shows an example of the optical key system concerning embodiment of this invention. It is an irradiation light spectrum figure which shows an example of the irradiation light to the optical filter concerning embodiment of this invention. It is a functional block diagram which shows the main function structures of the optical key system concerning embodiment of this invention. It is a top view which shows the modification of the optical key concerning embodiment of this invention. It is a flowchart which shows the outline | summary of the usage condition of the optical key system concerning embodiment of this invention. It is a sectional side view in each step at the time of insertion of the optical key which shows the outline | summary of the usage condition of the said optical key system.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10, 10a ... Optical key, 11 ... Board | substrate part, 12 ... Holding part, 13 ... Optical filter group, 13a ... Optical filter, 14 ... Slider, 15 ... Cover member, 16, 16a, 16b, 16c ... Guide hole, 17 ... Opening, 18, 18a, 18b, 18c ... Reference hole, 20 ... Optical key system, 21 ... Authentication room, 22 ... Insertion hole, 23 ... Illumination light source, 24 ... Illumination light, 25 ... Aperture hole, 25a ... Aperture Hole plate, 26 ... Grating, 27 ... Line sensor, 28 ... Determining unit, 29a, 29b ... Grip roller, 31 ... Filter information reading unit, 32 ... Irradiated light spectrum reading unit, 33 ... Filter position detecting unit, 34 ... Data temporarily Storage unit 35 ... Filter information calibration unit 36 ... CPU 37 ... Determination reference data memory unit 38 ... Filter information memory unit 39 ... Display , 40 ... hole for scale

Claims (13)

  An optical key characterized in that a plurality of optical filters having different light transmission characteristics are arranged on a key substrate surface, and the light transmission characteristics of each optical filter read by irradiation light constitute key information.   The optical key according to claim 1, wherein arrangement positions of the plurality of optical filters on the key substrate surface also constitute the key information.   In addition to the optical filter, the key substrate is provided with a light shielding member for the irradiation light or a transparent member for the irradiation light, and the arrangement positions of the light shielding member and the transparent member also constitute the key information. The optical key according to claim 2, wherein the optical key is a key.   4. The optical key according to claim 3, wherein the optical filter, the light shielding member, or the transparent member is fitted on the key substrate, and the arrangement position thereof is changed by sliding movement. .   The optical key according to any one of claims 1 to 4, wherein the optical filter is a visible light interference filter.   The optical key according to claim 5, wherein the optical filter is a single wavelength pass filter, a multiple wavelength pass filter, a band pass filter, a long wave pass filter, or a short wave pass filter.   The scale hole for detecting the arrangement | positioning position of the said optical filter, the said light-shielding member, or the said transparent member is provided in the said key board, The Claim 1 thru | or 6 characterized by the above-mentioned. The optical key described. An optical key in which a plurality of optical filters having different light transmission characteristics are arranged on the key substrate surface, and the light transmission characteristics of each optical filter read by the irradiation light constitute key information;
A light source of the irradiation light;
Key information storage means storing light transmission characteristics for determination criteria of the optical filter;
Filter information reading means for reading light transmission characteristics of the optical filter;
An authentication determination means for comparing the light transmission characteristics of the optical filter detected by the filter information reading means with the light transmission characteristics for determination criteria stored in the key information storage means to determine their identity; ,
An optical key system comprising:   9. The optical key system according to claim 8, further comprising filter position detection means for detecting a position of the optical filter.   The filter position detecting means detects an arrangement position of the optical filter on the key substrate surface, and the key information storage means stores the arrangement position of the optical filter on the key substrate surface for a determination reference; The optical authentication according to claim 8 or 9, wherein the authentication determination unit compares the arrangement position of the optical filter detected by the filter position detection unit with the arrangement position for the determination reference and determines their identity. Key system.   9. The optical key system according to claim 8, wherein the filter information reading unit calibrates a light transmission characteristic of the optical filter based on a spectral light intensity of the irradiation light.   The optical key system according to claim 9, wherein the filter position detecting unit includes a rotary encoder attached to a rotary roller that sends the optical key to an area to be irradiated with light.   10. The optical key system according to claim 9, wherein the filter position detecting means includes a linear encoder including a scale hole attached to the optical key.

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