JP2003286782A - Electronic key system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electronic key system having high safety allowing a wide range of use and integration. <P>SOLUTION: Features of fingerprints of a person gripping an electronic key are detected and extracted, and a coded key is made based on a built-in corresponding table. A signal for unlocking created by the coded key is transmitted to a key hole side, and the code is decoded by trying all of many decoding keys based on the corresponding table built-in at the key hole side. In this way, the key can be compared with the registered information storing the features of a person decoded; when the results of comparison coincide with each other, the person is considered as a certified person and the key is unlocked. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic key system which has high security, is easy to carry, and is relatively inexpensive.

[0002]

2. Description of the Related Art Conventional gate systems that guarantee security include, for example, locks at entrances and automatic ticket gates, keyless entries for automobiles, gates for exhibition halls, and gates for laboratories.

In addition, a gate for restricting people's entrance and exit is
Keys, electronic keys, various cards, special hardware, biometrics authentication, etc. are used. Here, the special hardware is, for example, an ID badge or the like, but in recent years, mobile phones and the like, which each person has one by one, have been listed as candidates.

The biometrics authentication is a characteristic of a human person (living body) who does not need to carry a cellphone.
It uses the difference.

As a device for unlocking the gate,
As the importance of the device increases, the non-disclosure and confidentiality of the device become indispensable for improving the security of the gate. On the other hand, from the viewpoint of portability and loss prevention, the size of these devices is naturally limited.

Considering these points, the key and the card including the electronic key have optimum characteristics.
Since ancient times, there is a cryptographic technique as a technique for improving the security. In particular, the public key type encryption technology developed in recent years has high security, and if this is used for a key or a card including the electronic key, electronic signature or encrypted communication is possible.

[0007]

However, although the key and the card are highly portable in size, they are likely to be lost as compared with the biometrics authentication.

The information used for the biometrics authentication includes (1) face, (2) voice print, (3) handwriting,
(4) fingerprint, (5) palm print, (6) iris, (7) retina,
There are (8) veins, (9) keystrokes, (10) DNA, etc.

[0009] Here, (1) and (2) have a problem of confidentiality, (5) may be widely distributed as a bill, and (10) is easily available. There is. Also, (3) and (9) are still worried about the degree of perfection of the technology. The remaining candidates are (4),
There are (6), (7), and (8). In particular, the fingerprint of (4) has good compatibility with the key, as seen in, for example, Japanese Utility Model Laid-Open No. 7-14048.

However, in a simple fingerprint detection, if the pattern of the fingerprint is copied by a copying machine or the like and used as a substitute, authentication (misidentification) with the person can be easily obtained, and security is improved. Is not necessarily high. Also,
In recent years, when the fingerprint is detected, other biometrics detection (biological detection), which also detects the blood vessel structure inside the finger as in (8), is commonly used together. . In that respect, (6) and (7) are difficult to duplicate, but for authentication, the eye must be brought close to an optical sensor for performing the authentication, and its use is naturally limited. I will end up.

In the present situation, there are a large number of keys and cards according to their uses. Especially, the latter card is so remarkable that a card holder can be formed.
This is a very annoying situation, and if it can be integrated like a multi-remote control, it is most desirable.

There is also a keyless entry technique (for example, Japanese Examined Patent Publication No. 5-22791) which unlocks the key wirelessly in the automobile or the like, but the wireless is not suitable for the above-mentioned uses because of its openness. It is not suitable. Similarly, there is a technique using infrared rays (for example, Japanese Patent Laid-Open No. 10-169273), but for the same reason, it is hard to say that it is suitable for a gate system that guarantees security.

Therefore, the present invention has been made in order to eliminate the above-mentioned drawbacks, and can be applied to a wide range of applications having high security. Moreover, when a key or a card is lost, a minimum damage is caused. Moreover, it is an object of the present invention to provide an electronic key system which does not work and which can be realized by a combination of technologies which are currently at a sufficient level for realization.

[0014]

[Means for Solving the Problems] Under such a purpose,
High security in the present invention is guaranteed by having the following configuration. (1) Adoption of hardware, (2) Non-use of wireless,
(3) Employing fingerprint detection with relatively high confidentiality, (4) Other biometrics detection performed at the same time as fingerprint detection,
(5) adoption of electronic key, (6) combination of mechanical unlocking and electrical unlocking, (7) adoption of encryption technology, (8) adoption of public key system

The present invention employs hardware that is strong against duplication. This is because, if only pure software such as ID and password is used, it can be easily duplicated in case of leakage.

Further, an electronic key capable of mechanical unlocking (opening and closing) and electrical unlocking is used. Moreover, it is desirable that the electric signal for performing the electrical unlocking flow through the electrical contact formed in the portion for performing the mechanical unlocking. This is because the portion where the mechanical unlocking is performed is protected by the keyhole side into which the key is inserted, so that when the electric signal flows, the signal is also protected by the keyhole.

On the surface of the key, the above-mentioned actual flat plate 7 is used.
As in No. 14048, a pad for fingerprint detection is formed, and the fingerprint is detected by the pad. A key for unlocking is created from the detected fingerprint, and an encrypted electric signal for unlocking is created using the key and transferred to the keyhole side to unlock. Further, if the other biometrics amount is also detected in the pad, the problem of copying the fingerprint can be dealt with as described above.

Further, by encrypting the electric signal that is exchanged with the keyhole side, it is possible to prevent a third party from deciphering a leaked electric signal (radio wave) or the like.

The following technical means are used for a wide range of applications and their integration. (1) Adopting the same key lock and the same mechanical unlocking device,
(2) Adoption of card shape, (3) Separation of supplied signal (control signal) and encryption.

In the present invention, in order to unlock different keyholes with a single electronic key, it is first necessary for both key ridges and the mechanical unlocking device to match. From this point of view, the card shape has a standardized outer shape, which is advantageous for widening the application of the single key. Further, in the card shape, it is conceivable that the keyhole and the mechanical unlocking device are not provided.

On the other hand, the electrical unlocking device of the present invention does not necessarily have to be the same as the keyhole, but in order to establish communication between the electronic key side and the keyhole side, the encryption key used in advance is Must match. This means registration of the fingerprint on the keyhole side in advance.

In the registration, it is indispensable that at least the invariant characteristic point information of the fingerprint of the person concerned and the corresponding key (s) for decrypting the encryption exist on the keyhole side. These must be common to all keyholes. However, the control signal which is the source of the unlock signal to be supplied to the electronic key side does not necessarily have to be the same. For example, it is possible to change the frequency, pulse waveform, voltage amplitude, etc. with different keyholes.

Therefore, even if one of the control signal and the unlock signal leaks in one gate system (electronic key system), those signals cannot be used in the other gate systems. As described above, the present invention has very strong resistance to the signal for breaking the lock intentionally created by a third party.

Further, according to the present invention, like a multi-remote controller, a large number of keyholes can be handled with a single electronic key.

In order to minimize the damage when lost,
The following technical means are used. (1) adoption of biometrics authentication technology called fingerprint detection, (2) adoption of public key method, (3) adoption of material for preventing fingerprint clarification, (4) non-recording of personal fingerprint information on electronic key, (5) The electronic keys are equipped with the minimum required functions.

According to the present invention, the electronic key has a fingerprint detecting function so that it cannot be used by a third party when it is lost. Also,
By adopting the public key on the electronic key side, it is possible to minimize the damage when it is lost. Since the public key does not cause any problem even if it is made public, there is no problem of key leakage even if the key is lost.

In the biometrics authentication, there is no risk of loss except for DNA, but there is a constant risk of duplication like fingerprints. That is, although biometrics authentication is easy and efficient, it has an unexpectedly large bomb that leaks the characteristics of the individual. This is convincing, considering the fraudulent use of the fingerprint.

Therefore, in the present invention, the device is positively devised so that a clear fingerprint does not remain on the electronic key. That is, by devising the material of the electronic key, selecting a material that does not adhere to the fingerprint, making it difficult for oil and fat components and water to adhere to the pad portion, or vice versa, making a large number of fingerprints sticky. It is achieved by making each one clearly inseparable. In addition, of course, the fingerprint information of the person concerned is not recorded as a record in the electronic key.

Moreover, by constantly assuming loss,
No unnecessary functions are installed on the side of the electronic key that may be lost. For example, the electric power for driving the key is supplied from the keyhole side and does not include a battery or the like.

Further, the source of the unlock signal output to the keyhole side is supplied from the keyhole side, and the electronic key only modulates the signal. As a result, the frequency and pulse waveform of the electric signal will not leak to a third party even if the key is lost. It should be noted that minimizing the function of the electronic key also leads to inexpensive manufacture of the key.

[0031]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

The external appearance of the electronic key according to the first embodiment of the present invention is shown in FIG. Reference numeral 21 is an electronic key body, and a grip 23
A sensor array 26 for fingerprint detection is formed on the.
Further, four electrical contacts 25 are provided at the tip of the key 22.

FIG. 3 shows a system block diagram on the electronic key side of this embodiment. Reference numeral 35 denotes the above-mentioned four electrical contacts, one for power supply, one for signal reception, one for signal transmission, and one for ground (GND). The two power lines of the electrical contacts are connected to each device.

Reference numeral 36 is a sensor array having a size of 2 cm square and the pressure type sensor is integrated in total of 160,000 pixels. The surface of the sensor array 36 is treated with a fluorine resin (Teflon (R)) so that the fingerprints do not easily adhere to it.

37 is A integrated on a monolithic IC
It is a D converter (ADC). Monolithic IC3
7 is mounted in a form embedded in the grip 23 of FIG.

The ADC 37 outputs the analog signal output from the sensor array 36 in 8 bits (256 bits) in real time.
Convert to a digital signal of (gradation).

Reference numeral 38 is a frame memory of 160 kbytes which is also integrated on the monolithic IC, and can store one frame image of the sensor array.

Reference numeral 40 is an 8-bit CPU which is also integrated on the same IC. Reference numeral 39 is also a semiconductor memory integrated on the same IC, and is composed of a 4-Mbit RAM and a 1-Mbit ROM. The program of the CPU 40 is stored in the ROM.

The frame memory 38 and the memory 39 are connected to the CPU 40 by a bus to enable high speed data transfer. Further, from the CPU 40, an electrical connection 35 and three signal lines (for signal reception, signal transmission, GN) are provided.
It is connected in D).

FIG. 4 shows a system block diagram of the electronic key system on the keyhole side. 46 is a power source for driving the system. Part of the electric power supplied from the power supply 46 is also supplied to the electronic key side through the electrical contact 41. Reference numeral 42 denotes a CPU, which supplies a control signal for unlocking to the electronic key side through four wires connected to the electrical contacts 41, in addition to controlling the system on the keyhole side. In this embodiment, the signal is the simplest signal CP
It is the basic clock for controlling U40.

Reference numeral 43 is a semiconductor memory, which is connected to the CPU 42 by a bus. In the memory 43, in addition to the program of the CPU 42, a key for decrypting the cipher used for communication with the electronic key is stored. The key corresponds to an encryption key and is stored in the form of a correspondence table so as to correspond to the characteristic points of the fingerprint. Reference numeral 44 is a database memory for storing the registered fingerprint information. In the database 44, the feature point information of the registered fingerprint of the person is stored for each person.

Reference numeral 45 is an electric unlocking device controlled by the CPU 42. Upon receiving an unlocking or locking command from the CPU 42, the unlocking device 45 controls a physical electric lock (not shown) to perform unlocking and locking, respectively. 47
Is a mechanical unlocking device existing independently of the electrical unlocking device 45 and the electric circuit, and unlocks only by a physical key crest 24 formed on the key 22 of the electronic key.

FIG. 1 shows an operation flow of the electronic key system of the present invention, and the operation will be described. When the electronic key 21 is correctly inserted into the keyhole, electrical contact is established between the electrical contacts 35 and 41, and power is supplied from the power supply 46 (S10).
0). Then, the electronic circuit on the electronic key side is turned on (S1
01), the sensor array 26 for fingerprint detection arranged on the grip 23 of the key starts its sensing (S10).
2). The sensing is performed once per second, and the acquired frame image is stored in the frame memory 38 as described above. The CPU 40 extracts feature point information from the image based on the stored feature point extraction program (S).
103). The feature points include end points, branch points, and their relationships. The extracted information is stored in the memory 39. Then, based on the correspondence table stored in advance in the ROM, the feature point information is converted into an encryption key (S
104). The encryption key is a public key of RSA (Rivest-Shamir-Adolman) encryption.

After the key is generated, the control signal (basic clock, repeated signal of 0 and 1) supplied from the keyhole side is encrypted using the key (S105).
The control signal is a 0, 1 digital rectangular wave having a frequency of 100 kHz and an amplitude of 1.5V. The crest with a voltage of 0V corresponds to 0 of the signal, and the crest of the voltage of 1.5V corresponds to 1 of the signal. Information on the control signal is stored in the memory 43 in advance. The control signal is supplied from the CPU 42 to the electronic key side through the electrical contacts 41 and 35 and the signal receiving wiring. An unlock signal is created by modulating the supplied control signal by the CPU 40 using the encryption key. Similarly, the unlock signal is sent to the CPU on the keyhole side through the signal transmission wiring and the electrical contacts 35 and 41.
It is returned to 42 (S106).

The received encrypted signal (unlocking signal) is attempted to be decrypted (deciphered) by the secret key stored in the memory 43 corresponding to the public key (S107).

The secret key whose information of the decrypted signal matches the information of the control signal transmitted to the electronic key side is the key corresponding to the public key. A person who has the feature point information operating the key by reading out the feature point information corresponding to the secret key existing in the database 44 and comparing it with the invariant feature point information also existing in the database 44. It is determined whether or not is registered (S108). That is, when all the invariant characteristic point information is included in the decrypted characteristic point information, the person who operates the key is authenticated as the registered person.

When the personal authentication is performed, the CPU 42
Issues an unlocking command to the electrical unlocking device 45, and the electrical unlocking is performed (S109). As a matter of course, when the personal authentication is not performed, the electrical unlocking is not performed. Thereafter, the person holding the electronic key also unlocks the mechanical unlocking device 47 by rotating the key crest 24 of the key by turning the key. This unlocks the keyhole.

The present embodiment has a very high security because the electronic key is combined with the fingerprint detection technology and the encryption technology. Further, since the public key is used, the electronic key is resistant to loss.

In this embodiment, the pressure type is used as the sensor array 26 for detecting the fingerprint, but other known sensors such as capacitance type and optical type may be used.
Also, the number of electrical contacts need not be four, and may be any number.

For example, if the signal receiving wiring and the signal transmitting wiring are also used, the number of the electrical contacts becomes three. The reception and transmission are performed using different times.

The encrypted signal is generated by combining the control signal, which is the source of the unlock signal, with a signal different from the basic clock for controlling the CPU 40, that is, a combination of 0 and 1 information of finite length. Can be more difficult to decipher.

The control signal need not be a binarized signal, but may be an arbitrary multi-valued signal. It is also conceivable to transmit the control signal via a plurality of wirings. For example, by setting the potential difference between the two wires as the value of the signal, it becomes more difficult to decipher by leaking radio waves. Further, the registered fingerprint database 44 may be formed in the memory 43.

The public key is not limited to the RSA cipher, but may be a known public key such as Rabin cipher, Williams cipher, Matsumoto-Imai cipher, or the like.

In addition to the combination of the public key and the encryption key, it is naturally possible to use a common key for the encryption and the decryption. In this case, the loss of the key will cause some damage. However, although there is a correspondence table in the key, since the information of the encryption key used for encryption is not recorded (it is different every time), this application example is naturally conceivable.

Further, as a second embodiment of the present invention,
As shown in FIG. 6, an example in which the electrical contact 65 is formed in the key mountain 64 which is the geometrical structure on the electronic key side is shown.

According to the present embodiment, when the key is inserted and electric signals are exchanged, the contacts are embedded and protected in the cylinder having the geometric structure on the keyhole side, so that the contacts from the outside are more protected. It becomes difficult to eavesdrop on the electric signal, and security is improved.

In addition, as a third embodiment of the present invention,
A card shape as shown in FIG. 5 is also conceivable. The third embodiment does not have a mechanical unlocking device. Reference numeral 56 is a capacitance type sensor array for detecting fingerprints. Reference numeral 55 is an electrical contact for transmitting the fingerprint information to the keyhole side.

The card shape of the third embodiment is being standardized, and even for an existing gate system (card system), a part (program) change or the like can be applied to the card (electronic key). It is possible to respond. Therefore, the electronic key system can be further spread.

In addition, as a fourth embodiment of the present invention,
An example will be given in which a private key is used on the electronic key side and a public key is used on the keyhole side. The electronic key system according to the fourth embodiment corresponds to, for example, an amusement park, a museum, an exhibition hall, etc. having a large number of gates. On the large number of gates, that is, on the keyhole side, public keys are prepared by a correspondence table so as to correspond to various types of feature points extracted from various fingerprints. These correspondence tables and many public keys are common to all gates.

On the other hand, an electronic key corresponding to the gate is distributed to the participants who pass through the gate, and when the user uses one of the gates to pass through any of the gates, the participant does the same as described above. The electronic key detects the fingerprint of the electronic key, the private key is formed from the characteristic points of the fingerprint by the built-in correspondence table, and the encrypted signal encrypted by the private key is transmitted to the gate.

In this way, the gate side can decrypt the cipher with any of the public keys. The characteristic point information corresponding to the successfully decrypted public key is stored in the gate or a system that integrates the gate system as fingerprint information of the participant who has passed through the gate.

According to the fourth embodiment, it is obvious at which gate the participant passed through. For example, when the participant exits the amusement park or the like, the participation fee is passed through the gate. It is possible to make a claim with a difference depending on the presence or absence.

In addition, as a fifth embodiment of the present invention,
An example in which other biometrics information is also detected in the sensor array for detecting fingerprints will be shown. The sensor array is a capacitive sensor array formed on a glass substrate and having a size of 20 mm square, a number of pixels of 400 * 400, and a pixel size of 50 μm. In addition to the capacitance type sensor, a resistance thermometer for temperature detection is formed in the pixel, and when a finger is pressed against the sensor array to detect a fingerprint,
The temperature that rises in response to the body temperature from the finger is detected.

By pressing the finger, the temperature rises most in the central portion where the pressure is high, and the temperature rise of the thermometer hardly occurs in the peripheral portion where the finger does not touch. By knowing the temperature distribution on the sensor array, the pressed finger can be determined to be a living body.

According to the fifth embodiment, for example, a counterfeit fingerprint pattern or the like copied by a copying machine or the like can be eliminated without being erroneously recognized by the sensor array. This further improves security.

Other biometrics information used in combination with the present invention includes, in addition to the above, blood vessel distribution information in the finger, oil / fat component information, sweat component information, pH degree, and the like.

As a sixth embodiment of the present invention, a flow for registering the fingerprint in the electronic key system will be described with reference to FIG.

First, a person who performs registration inserts an electronic key into a keyhole to prepare for registration (S200). After confirming that there is no person registered in the electronic key on the keyhole side,
Prepare to register the electronic key.

First, a control signal is sent to the electronic key side (S2
01), then the person presses the fingerprint of his / her finger against the sensor array to detect the fingerprint (S202). After detecting the fingerprint, the electronic key extracts the characteristic points of the fingerprint (S2
03), an encryption key for modulating the control signal is created according to the built-in correspondence table (S204).

Next, encryption is performed (S205) and the encrypted signal is transmitted to the keyhole side (S206). The received encrypted signal is attempted to be decrypted by a large number of decryption (decryption) encryption keys in the registered fingerprint database (S20).
7).

The feature point information is obtained from the encryption key that has been successfully decrypted using the built-in correspondence table (S208), and the feature point information is stored in the memory on the keyhole side. This is 1
It is performed 0 times (S209).

Since the fingerprint information extracted by the electronic key is slightly different each time, only the feature point information common to all of them is extracted on the keyhole side (S210) and registered as the fingerprint information of the person (S210). S211). The registered fingerprint information is stored in the database.

At the same time, the electronic key side is informed of the completion of the registration, and the PROM on the electronic key side is rewritten to record that there is a person registered in the electronic key.
As a result, new (personal) registration for this electronic key will no longer be possible.

According to the present invention, no new device is required to register the person. Further, even if the key is lost, a new person cannot be registered using the key, so there is no problem in security.

Further, if a highly irreversible fuse ROM or one-shot ROM is used for the PROM used in this embodiment, rewriting from the outside is impossible and the security is further enhanced.

[0076]

As described above, according to the present invention, it is possible to inexpensively provide an electronic key system having a high security and a wide range of applications.

[Brief description of drawings]

FIG. 1 is an operation flow chart of an electronic key system to which the present invention is applied.

FIG. 2 is an external view of an electronic key to which the present invention has been applied.

FIG. 3 is a system block diagram on the electronic key side.

FIG. 4 is a system block diagram of an electronic key system on a keyhole side.

FIG. 5 is an external view of a card-shaped electronic key to which the present invention is applied.

[FIG. 6] In a key mountain that is a geometric structure on the electronic key side,
It is an external view of the electronic key which formed the electrical contact.

FIG. 7 is a flowchart when a fingerprint is registered in the electronic key system.

[Explanation of symbols]

21, 51, 61 Electronic key 22, 62 key 23, 63 grips 24, 64 Key Mountain 25, 35, 41, 55, 65 electrical contacts 26, 36, 56, 66 sensor array 37 ADC 38 frame memory 39,43 memory 40, 42 CPU 44 registered fingerprint database 45 Electrical unlocking device 47 Mechanical unlocking device

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁷ identification code FI theme code (reference) G06T 1/00 400 G06T 1/00 400G 7/00 300 7/00 300F F term (reference) 2E250 AA02 AA03 AA04 AA12 AA21 BB05 BB09 BB68 CC11 DD09 EE09 FF08 FF18 FF43 FF44 FF53 HH01 JJ03 KK01 KK03 LL01 2F051 AA00 AB06 AC07 BA08 5B047 AA25 BA02 BB10 BC14 BC15 FA14 DC15 5B0757 BA33 DC15 5B0757 BA33 DC11 DB02 DB33

Claims (14)

[Claims] 1. With respect to an electronic key having a fingerprint detection function, a signal for unlocking or locking a lock issued from the electronic key extracts the characteristic point from a fingerprint of a person who holds the electronic key, Creating a key from the information of, the signal encrypted using the key is output to the keyhole side, the signal is decrypted on the keyhole side using a predetermined prepared key corresponding to the key, An electronic key system characterized in that the person holding an electronic key is authenticated to unlock or close the lock. 2. The electronic key according to claim 1, wherein the electronic key has a geometric structure for mechanically unlocking and locking, in addition to an electrical contact for transmitting the signal. Key system. 3. The electronic key system of claim 2, wherein the electrical contacts are embedded in the geometric structure. 4. The electronic key system according to claim 1, wherein the electronic key has a card shape. 5. The electronic key system according to claim 1, wherein the signal is generated by electric power supplied from a keyhole side on which the electronic key is inserted. 6. The electronic key system according to claim 1, wherein the signal is generated by modulating a signal waveform supplied from a keyhole side on which the electronic key is inserted. 7. The electronic key system according to claim 1, wherein the two-dimensional sensor array for detecting the fingerprint can also detect biometrics information other than the fingerprint. 8. The electronic key system according to claim 7, wherein the two-dimensional sensor array is made of a material that is hard to clarify the fingerprint. 9. The electronic key system according to claim 1, wherein the key is a common key. 10. The electronic key system according to claim 1, wherein the key is a public key. 11. The electronic key system according to claim 1, wherein the key is a secret key. 12. In the personal identification, feature points of a fingerprint of a person who performs the personal identification are extracted at least a plurality of times, and only reproducible feature points extracted over the plurality of times are registered in advance as registered fingerprint information. The electronic key system according to claim 1, wherein the characteristic point information stored and stored in the fingerprint detected by the electronic key is compared with the registered fingerprint information. 13. The electronic key system according to claim 12, wherein the registration of the fingerprint information is performed on the keyhole side on which the electronic key is inserted. 14. The personal authentication, wherein the personal authentication is performed when all of the stored characteristic points are included in the characteristic points extracted from the fingerprint. Electronic key system.