JPH11347015A - Individual pattern detecting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the ability of a vascular pattern detecting device to reproduce an individual vascular pattern by preventing the influence of temperature in the measuring atmosphere on recognizing an individual based on the vascular pattern of the individual. SOLUTION: This device has at least an applying part 2 which is applied to a part 1 to be measured, a temperature control part 3 to keep the applying part 2 at a prescribed temperature, a heat conductive part 4 to transfer heat to the applying part 2, a heat source 5 and a heat sensor 6 installed in the heat conductive part 4. The temperature control part 3 controls the electricity to be supplied to the heat source 5 based on the temperature data fed back from the output of the heat sensor 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a personal characteristic pattern detecting apparatus for identifying an individual using characteristics of a blood vessel pattern below a body surface.

[0002]

2. Description of the Related Art Heretofore, identification of an individual has been used mainly for giving permission to use a bank terminal or a computer, or for controlling entry and exit to a room having a limited number of persons. In these cases, a method using a personal identification number or a password has been mainly used for personal identification. However, recently, technology for performing personal identification using characteristics of a living body has been developed.

As one of the methods, a method using a blood vessel pattern of the back of a hand or a finger is known. That is, a method of utilizing the blood vessel pattern of the back of the hand is disclosed in British Patent No. 2156127B and Magazine "Sensor Review" Vol. 12, No. 3 (1992), pp. 19-23. In addition, a photograph of the blood vessel pattern on the back of the hand due to transmitted light was published in the magazine “Pathophysiology,” Vol.
Years) pp. 620-629. A method using a blood vessel pattern of a finger is disclosed in Japanese Patent Application Laid-Open No. 7-21373.

[0004]

The method of utilizing a blood vessel pattern in the body has an advantage that security is enhanced because it is difficult to steal or forge. In these conventional examples,
A blood vessel pattern close to the body surface of a measurement site is measured using intensity measurement of transmitted light or reflected light in the near infrared that is relatively easy to penetrate a living body (hereinafter, this measurement method is referred to as a transmission method or a reflection method).

However, the target peripheral blood vessel expands and contracts depending on the measurement environment temperature such as room temperature, so that a blood vessel pattern with good reproducibility cannot be obtained by the transmission method or the reflection method, and the accuracy of identification deteriorates. For example, it has been found that there is a problem that the temperature of the measurement site is different between winter and summer, and between outdoor and indoor where measurement environment temperatures are different, and a blood vessel pattern is different between a cold environment in which blood vessels contract and a hot environment in which blood vessels expand. This problem is not described in the above-mentioned conventional example.

It is an object of the present invention to provide a personal characteristic pattern detecting apparatus which improves the reproducibility of a blood vessel pattern by preventing the influence of a measurement environment temperature in personal identification of a blood vessel pattern of a living body.

[0007]

In order to prevent the fluctuation of the blood vessel pattern due to the influence of the temperature of the measurement environment, the problem can be solved by keeping the temperature of the measurement site mounting portion for mounting the measurement site within a certain temperature. That is, in the personal characteristic pattern detection device,
Incorporates a heat source, heat conducting part, measuring part mounting part, heat sensor, and temperature control part, and sets the measuring part mounting part to a set temperature before photographing the blood vessel pattern under the measuring part to keep the measuring part at a constant temperature. The problem can be solved by adjusting within. The specific method of personal identification after obtaining a blood vessel pattern is described in the above-mentioned magazine “Sensor Review”, Vol.
No. (1992), pages 19 to 23, JP-A-7-21373, etc., and these methods may be used.

[0008]

FIG. 1 is a block diagram showing an embodiment of a temperature setting section of a personal characteristic pattern detecting apparatus according to the present invention. The configuration and basic operation of the device will be described. The personal characteristic pattern detecting device includes a measuring part mounting part 2 for mounting the measuring part 1, a temperature control part 3 for setting the measuring part mounting part 2 at a constant temperature, and a heat conducting part 4 for transmitting heat to the measuring part mounting part 2. , A heat source 5 and a heat sensor 6 installed in the heat conducting unit 4, a measuring unit (not shown, which will be described later) of a blood vessel pattern acquired from the measurement site 1, and an identifying unit (not shown, which is publicly known).

As a measuring method of the measuring unit, nuclear magnetic resonance and ultrasonic waves can be used in addition to a transmission method or a reflection method using near-infrared light as exemplified in the following embodiments. The measurement part 1 can be an arbitrary part such as a hand (the back of a hand or a finger), an earlobe, etc. The measurement part mounting part 2 has a shape suitable for the measurement part 1, and the temperature control part 3 is a well-known electronic circuit engineering. Circuit. A material having high thermal conductivity such as aluminum or brass is used for the heat conducting part 4, a heater is used for heating, a Peltier element is used for heating or cooling, and a thermistor is used for the heat sensor 6. And the thermocouple, etc. in the identification section, the above-mentioned magazine “Sensor Review”, Vol. 12, No. 3, (1992), p.
Page or a method known in JP-A-7-21373 and the like.

Next, as an operation, when a set temperature is designated by the temperature control unit 3, heat is transmitted from the heat source 5 to the heat conduction unit 4,
The temperature is detected by a heat sensor 6 installed in the heat conducting section 4. Since the thermal conductivity of the heat conducting portion 4 is extremely high, such as aluminum or brass, the temperature difference between the heat source 5 and the thermal sensor 6 can be ignored. The temperature control unit 3 is designed to control the power supplied to the heat source 5 based on temperature information fed back from the output of the heat sensor 6. That is, the temperature control unit 3 controls the power supplied to the heat source 5 based on the difference between the temperature of the heat sensor 6 and the set temperature of the temperature control unit 3, thereby controlling the measurement site mounting unit 2 to the set temperature. The measurement site 1 can be kept within a certain temperature during measurement.

The set temperature of the temperature control unit 3 is a body temperature 3
In addition to the temperature around 7 ° C., the temperature around the annual average temperature and the comfortable temperature around 20 ° C. in a room where the temperature is controlled may be used, but other temperatures may be used as long as they are constant values in the use environment. . From our experimental results, it is necessary that the fluctuation range with respect to the set temperature be at most ± 5 ° C., and preferably within ± 1 ° C. if possible.

FIG. 2 shows data of finger blood vessel distribution based on a temperature difference in the near-infrared light transmission method. FIG. 2A shows a case where the set temperature is 20 ° C., and FIG. 2B shows a case where the set temperature is 5 ° C. It is. 5
The blood vessels 10, 11 and 12 that do not appear to contract at
The data appears to expand in ° C., and indicates the importance of maintaining the measurement site at a constant temperature.

The present embodiment has the effect of realizing an apparatus for detecting an individual characteristic pattern of a blood vessel pattern, which prevents the influence of the measurement environment temperature and improves the reproducibility of data required for identification.

FIG. 3 is a sectional view showing an embodiment of the personal characteristic pattern detecting apparatus according to the present invention. The configuration and basic operation of an apparatus for measuring a blood vessel pattern under the measurement site under the reflection method using near-infrared light as a target will be described.

The personal characteristic pattern detecting device of the present embodiment
A measurement part mounting part 2 for mounting the measurement part 1, a temperature control part 3, a heat conduction part 4, a heat source 5, a heat sensor 6, a light source 20, an emitted light 21, an optical lens 22, a photodetector 23, a reflected light 24,
And an identification unit (not shown because it is publicly known). The measurement site 1 can be an arbitrary site. Here, the measurement site 1 is a hand (the back of a hand, a finger, or the like), the measurement site mounting unit 2 has a flat shape in which the hand of the measurement site 1 can be easily placed, and the temperature control unit 3 is publicly known. Electronic circuit.

A material having high thermal conductivity such as aluminum or brass is used for the heat conducting part 4, a heater is used for the heat source 5, a Peltier element is used for the heat for cooling or cooling, and a heat sensor 6 is used for the heat sensor 6. Denotes a thermistor or a thermocouple, a light source 20 includes a semiconductor element such as a light-emitting diode or a laser diode for near-infrared light, an optical detector 23 includes an imaging element such as a CCD camera, and an identification unit includes the magazine “ Sensor Review 1
Volume 2, Issue 3 (1992), pp. 19-23, or
A method known in, for example, JP-A-7-21373 was used.

Here, a semiconductor element for near-infrared light is used as the light source 20, but near-infrared light obtained by dispersing light from a xenon lamp or the like is used as the outgoing light 21 or reflected from a xenon lamp or the like. A near-infrared light filter may be provided before the light detector 23 for the light 24.

The light 21 emitted from the light source 20 is
The light is condensed at 2 and irradiates the measurement site 1. Near-infrared light that has entered the measurement site 1 from the irradiation side is transmitted through the body while being scattered and absorbed by living tissue, and is greatly absorbed by blood vessels. On the other hand, the reflected light from the living tissue or blood vessel is transmitted through the body while being scattered or absorbed by the living tissue and returns to the body surface, similarly to the outward path. Near-infrared light is absorbed little by living tissue and is greatly absorbed by hemoglobin in blood vessels. Therefore, when the near-infrared light is emitted from the body surface of the measurement part 1 to the outside of the body, blood vessels are formed near the surface on the emission side of the measurement part 1. If there is, near-infrared light is greatly absorbed by hemoglobin in the blood vessel, and a shadow of the blood vessel pattern is projected on the emission side surface of the measurement site 1. The reflected light including the blood vessel pattern on the body surface is condensed by the optical lens 22 and then detected by the light detector 23 as reflected light 24. Temperature control unit 3
The operation of, and the set temperature and the fluctuation range with respect to the set temperature are as shown in the first embodiment.

In this embodiment, the reflection method has an effect of realizing an apparatus for detecting an individual characteristic pattern of a blood vessel pattern with improved data reproducibility required for identification and authentication.

FIG. 4 is a sectional view showing another embodiment of the personal characteristic pattern detecting apparatus according to the present invention. A configuration and a basic operation of an apparatus for measuring a blood vessel pattern under a measurement site by a transmission method using near-infrared light as a target will be described. The personal characteristic pattern detection device includes a measurement site mounting unit 2 for mounting the measurement site 1, a temperature control unit 3, a heat conduction unit 4, a heat source 5, a heat sensor 6, a light source 20, an emission light 21, optical lenses 22, 25, and light. It comprises a detector 23, transmitted light 26, and an identification unit (not shown because it is publicly known). Measurement site 1
Can be an arbitrary part. Here, a hand (the back of the hand or a finger, etc.) is used, and the measurement part mounting part 2 has a planar shape in which the hand of the measurement part 1 can be easily placed. A material transparent to near-infrared light, for example, transparent acrylic or transparent glass was used.

A known electronic circuit is used for the temperature control unit 3, a material having high heat conductivity such as aluminum or brass is used for the heat conduction unit 4, a heater for heating is used for the heat source 5, and a heater for cooling or heating is used. A Peltier element is used for cooling, a thermistor or a thermocouple is used for the heat sensor 6, a semiconductor element such as a light emitting diode or a laser diode for near infrared light is used for the light source 20, and a CCD camera is used for the photodetector 23. In the identification section, the above-mentioned magazine “Sensor Review”, Vol. 12, No. 3 (19)
1992) pages 19 to 23, or a method known in JP-A-7-21373 and the like.

Here, a semiconductor element for near-infrared light is used as the light source 20, but near-infrared light obtained by dispersing light from a xenon lamp or the like is used as the outgoing light 21 or transmitted from a xenon lamp or the like. A near-infrared light filter may be provided before the light detector 23 for the light 26.

The light 21 emitted from the light source 20 is
The light is condensed at 2 and irradiates the measurement site 1. Near-infrared light that has entered the measurement site 1 from the irradiation side is transmitted through the body while being scattered and absorbed by living tissue, and is greatly absorbed by blood vessels. Near-infrared light is absorbed little by living tissue and is greatly absorbed by hemoglobin in blood vessels. If there is, near-infrared light is greatly absorbed by hemoglobin in the blood vessel, and a shadow of the blood vessel pattern is projected on the emission side surface of the measurement site 1. The transmitted light 24 including the blood vessel pattern on the body surface is condensed by the condensing lens 22,
Is detected by The operation of the temperature control unit 3 and the set temperature and the fluctuation range with respect to the set temperature are as shown in the first embodiment.

In this embodiment, the surface to be imaged of the measurement site 1 (on the side of the photodetector 23) is configured to be in contact with the measurement site mounting portion 2, but when a shallow blood vessel below the body surface is crushed by the pressure at the time of mounting. In this case, the non-imaging surface (the light source 20 side) of the measurement site 1 may be configured to be in contact with the measurement site mounting unit 2 to obtain a blood vessel pattern. That is,
In FIG. 4, the vertical relationship between the measurement site 1 and the measurement site mounting unit 2 may be reversed, so that light transmitted through the measurement site mounting unit 2 is incident on the measurement site 1.

In the case of the transmission method, the light 21 emitted from the light source 20 may flow from the periphery of the measurement site 1 to the photodetector 23, and the blood vessel pattern may become unclear. In this case, a slit is effective. For example, only the minimum area in contact with the measurement site 1 is defined as the measurement site mounting unit 2, and the heat conduction unit 4 in contact with the measurement site mounting unit 2 is formed of a material that does not transmit near-infrared light.

FIG. 5 is a plan view showing another embodiment of the personal characteristic pattern detecting apparatus according to the present invention for supplementary explanation. The personal characteristic pattern detection device includes a measurement site mounting unit 2, a temperature control unit 3, a heat conduction unit 4, a heat source 5, a heat sensor 6, a measurement unit (not shown for the sake of description), which is a measurement site mounting unit 2 for mounting a hand, which is a measurement site 1. And an identification unit (not shown because it is publicly known). Compared to FIG. 4, the positional relationship between the measurement site 1 and the measurement site mounting unit 2 is reversed, and the heat conduction unit 4 is basically a material that does not transmit near-infrared light such as black plastic. Is the same configuration and material as in FIG. However, the shape of the measurement part mounting part 2 and the heat conduction part 4 are designed according to the shape of the hand that is the measurement part 1, and the heat source 5 is embedded in the heat conduction part 4 in a wide range in order to improve the heat conduction. .

The near-infrared light passes through the measurement site mounting portion 2 and the measurement site 1 in the vertical plane of the paper from the back of the paper toward the front, and the transmitted light including the blood vessel pattern is emitted toward the front of the paper. Therefore, this is detected by the photodetector. Other operations are the same as those in the embodiment of FIG.

These embodiments have the effect of realizing an apparatus for detecting a personal characteristic pattern of a blood vessel pattern with improved data reproducibility required for identification and authentication in the transmission method.

FIG. 6 is a schematic diagram showing an embodiment of the temperature setting section of the personal characteristic pattern detecting device according to the present invention. The configuration and basic operation of the device will be described. The personal characteristic pattern detection device includes a measurement part mounting part 2 for mounting the measurement part 1, a temperature control part 3, a heat source 5, a heat sensor 6, a heat conduction part including a cover 40 and a blower 41, and a part insertion into the cover 40. It comprises a unit 42, a measurement unit, and an identification unit (these are well known and are not shown).

In the present embodiment, by covering the measurement site with a cover, it is possible to realize an apparatus for detecting an individual characteristic pattern of a blood vessel pattern with improved data reproducibility required for identification.

As the measuring method of the measuring unit, it is possible to use nuclear magnetic resonance or ultrasonic waves in addition to the above-described transmission method or reflection method using near-infrared light. The cover 40 used a heat insulating material such as plastic, and the blower 41 used a fan or the like. The part insertion part 42 is provided by opening the cover 40, but may be an opening and closing part as described later. The other components such as the measurement site mounting unit 2, the temperature control unit 3, the heat source 5, the heat sensor 6, and the identification unit are as described in the first embodiment.

Next, as the operation, the blower 41 and the cover 40 of the heat insulating material play the role of the heat conducting portion in the above-described embodiment.
When the set temperature is designated by the temperature control unit 3, heat is transmitted from the heat source 5 into the cover 40, and the temperature is detected by the heat sensor 6 installed in the cover 40. The temperature control unit 3 is designed to control the power supplied to the heat source 5 based on temperature information fed back from the output of the heat sensor 6. That is, the temperature control unit 3 controls the power supplied from the temperature control unit 3 to the heat source 5 based on the difference between the temperature of the heat sensor 6 and the set temperature of the temperature control unit 3, so that the power is supplied from the part insertion unit 42 into the cover 40. The inserted measurement site 1 can be kept within a certain temperature at the time of measurement. The set temperature of the temperature control unit 3 and the fluctuation range with respect to the set temperature are as shown in the first embodiment.

In the present embodiment, the site insertion section 42
May be provided as an opening / closing section such as a door without being provided as an opening in a state of being always opened. In this case, the living body having the measurement site may be put into a cover, for example, a room with a door before measurement, and the living body may be taken out of the cover by opening the opening / closing unit after the measurement. According to the present embodiment, the comfortable temperature 2
Data with good reproducibility can be obtained in a room whose temperature is controlled to a temperature around 0 ° C.

[0034]

According to the present invention, since a measurement site set within a certain temperature is used for personal identification, it is possible to provide an individual characteristic pattern detection device which prevents the influence of the measurement environment temperature and improves the reproducibility of a blood vessel pattern. it can.

[Brief description of the drawings]

FIG. 1 is a block diagram of a temperature setting unit of a personal characteristic pattern detecting apparatus according to one embodiment of the present invention.

FIG. 2 is a diagram showing a blood vessel distribution of a finger according to a temperature difference in a near-infrared light transmission method.

FIG. 3 is a cross-sectional configuration diagram showing an embodiment of an individual characteristic pattern detection device according to the present invention.

FIG. 4 is a cross-sectional configuration diagram showing an embodiment of a personal characteristic pattern detection device according to the present invention.

FIG. 5 is a plan view showing an embodiment of a personal characteristic pattern detecting apparatus according to the present invention.

FIG. 6 is a schematic diagram showing an embodiment of a temperature setting unit of the personal characteristic pattern detecting device according to the present invention.

[Explanation of symbols]

1 ... measurement part, 2 ... measurement part mounting part, 3 ... temperature control part,
4: heat conduction part, 5: heat source, 6: heat sensor, 10-12 ...
Blood vessels, 20 light source, 21 outgoing light, 22, 25 optical lens, 23 photodetector, 24 reflected light, 26 transmitted light,
40 ... cover, 41 ... blower, 42 ... part insertion part.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Shinichiro Umemura 1-280 Higashi Koigakubo, Kokubunji-shi, Tokyo Inside Central Research Laboratory, Hitachi, Ltd.

Claims (8)

[Claims] 1. An apparatus for imaging a blood vessel pattern under a body surface for personal identification, comprising at least a heat source, a heat conducting part, a measuring part mounting part, a heat sensor, and a temperature control part as constituent elements, An individual characteristic pattern detection device having a function of setting a temperature within a certain temperature. 2. An apparatus for personal identification by imaging a blood vessel pattern under a hand by irradiating the hand with near-infrared light transmitted through the hand or near-infrared light reflected from the hand. A personal feature pattern detection device including at least a heat source, a heat conduction unit, a measurement site mounting unit, a heat sensor, and a temperature control unit, and having a function of setting the measurement site within a certain temperature. 3. A heat conduction part for burying a heat source and a heat sensor, a measurement part mounting part having a planar shape in contact with the measurement part,
A temperature control unit is provided for controlling the power supplied to the heat source according to the difference between the temperature of the heat sensor and the set temperature to set the measurement site mounting unit within a certain temperature, and the measurement site mounting unit is provided in the heat conduction unit. 3. The personal characteristic pattern detecting device according to claim 1, wherein the personal characteristic pattern detecting device has a contact structure. 4. A heat conducting part for burying a heat source and a heat sensor, a measuring part mounting part made of a material which is planar in shape in contact with the measuring part and which is transparent to near-infrared light; Provide a temperature control unit that controls the power supplied to the heat source according to the difference from the set temperature and sets the measurement site mounting unit within a certain temperature, and the measurement site mounting unit transmits the near infrared light to the heat conduction unit. 3. The personal characteristic pattern detecting device according to claim 1, wherein the personal characteristic pattern detecting device has a structure in which the individual characteristic patterns contact each other in a plane in the optical axis direction. 5. A method according to claim 1, wherein only a minimum area in contact with the measurement site is a measurement site mounting portion, and a heat conduction portion surrounding the measurement site mounting portion is made of a material that does not transmit near-infrared light. The personal characteristic pattern detecting device according to claim 4, wherein 6. A heat conducting part comprising a heat source, a function of blowing heat generated from the heat source and a cover for insulating the blowing from ambient temperature, a measuring part mounting part for mounting a measuring part, and a heat sensor installed in the cover. 3. An individual according to claim 1, further comprising a temperature controller for controlling power supplied to a heat source based on a difference between a temperature of the heat sensor and a set temperature to set a measurement site within a certain temperature. Feature pattern detection device. 7. The personal characteristic pattern according to claim 1, wherein nuclear magnetic resonance or ultrasound is used as a means for imaging a blood vessel pattern under the body surface. Detection device. 8. The method according to claim 1, wherein the set temperature is about 37 ° C., about 20 ° C., or about the annual average temperature, and a fluctuation range with respect to the set temperature is up to ± 5 ° C.
Any one of the personal characteristic pattern detecting devices.