JPH11221203A - Individual identification device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an individual identification device constituting part of a security system utilizing information on a living body, which is extremely difficult to counterfeit, causes no psychological resistance, little physical constraining condition when utilizing, and is hardly influenced by a psychological or physical condition. SOLUTION: Signals reflecting an individual anatomical character of a finger tip, e.g. the backside shape of the nail body as well as the shape of the finger bone, and their positional relations are detected by a measuring probe 4. These data are compared by a comparison means 12 with corresponding data of a single or plural persons preliminarily stored in a memory 14, a determination is made by a judgment means 12 with reference to a certain value, and a judgment is given on whether to accept or reject. The result thereof is reported as a judgment result 18.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a personal identification device constituting a part of a security system, and more particularly, to a personal identification device using individual differences of living bodies as identification information.

[0002]

2. Description of the Related Art Conventionally, as a personal identification device used for entry / exit management in a highly confidential room or access control of a computer, etc., a personal identification device using characteristics of a human body such as a fingerprint, an iris, a fundus blood vessel, a handprint, and a face. A personal identification device using characteristics such as a voiceprint and a signature is known.

[0003] In addition to these known personal identification devices, recently, there has been an attempt to realize a personal identification device using anatomical features of the human body, which is difficult to forge. For example,
JP-A-4-502717 and JP-A-7-21373
Japanese Patent Laid-Open Publication No. Hei 8-508419 discloses a method using a blood vessel pattern of a hand or finger as a feature of personal identification.

[0004]

However, each of the above methods has the following problems. First, a personal identification device using fingerprints has a high psychological resistance to users because of the image of criminal investigation, and in order to popularize it, it can be used before the development of the device to eliminate the resistance of users. I have a problem that I have to think about how to do it. Also, in a personal identification device using a fingerprint or a handprint, a part of the body of an individual is used, so that there is a great risk of being duplicated.

Further, in an individual identification device using an iris, since the iris pattern is read by a camera, there is a possibility that the device is stolen by a similar method. Forgery is extremely difficult with a personal identification device that uses a fundus blood vessel pattern, but it is necessary to irradiate light to the eyes for detection, and there is a problem that a user's psychological burden is large. In a personal identification device that uses the shape of a face, it is necessary to keep the posture and lighting conditions within a certain range, which is inconsistent in stability and may be counterfeited in order to use the appearance. In addition, a personal identification device that uses a voiceprint or a signature has a high possibility of being stolen, and is susceptible to the user's mental state and health state, and lacks stability.

Further, a personal identification device using a blood vessel pattern of a hand or a finger is more difficult to forge than a personal identification device using an appearance feature, and a personal identification device using a fundus blood vessel pattern. The psychological burden on the elderly is small.
However, since near-infrared light or the like is used and information on a human body relatively close to the surface such as a subcutaneous vein is used, there is a possibility that a pattern may be stolen by a near-infrared camera or the like after all. In addition, since blood vessels are flexible tissues like muscles and fats, there is a high possibility that collation becomes difficult due to deformation or the like. In order to prevent this, the allowable range at the time of matching must be widened, and therefore, there is a problem that the erroneous authentication rate increases.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and has as its object the purpose of which is to make it extremely difficult to forge, to have no psychological resistance to the user, An object of the present invention is to provide a personal identification device using biometric information which has a small physical constraint and is hardly affected by a mental state or a health state.

[0008]

The object of the present invention is to provide a measuring means for measuring an anatomical feature of a fingertip of a person, a comparing means for comparing an output value from the measuring means with a stored value stored in advance, and a comparing means. And a determination means for generating a personal identification result in accordance with the comparison result of (1). The measuring means detects a signal reflecting at least the shape of the back side of the nail body of the fingertip. The measuring means detects a signal reflecting at least a bone shape of a fingertip. further,
The measuring means detects a signal reflecting at least a positional relationship between a fingertip bone and a nail.

In the personal identification device according to the present invention, the measuring means has an ultrasonic oscillation means for emitting an ultrasonic beam into a fingertip. Alternatively, the measuring means includes an illuminating means for irradiating light into a fingertip. The lighting means emits near-infrared light.

According to the personal identification device of the present invention, the anatomical feature of the fingertip, such as the shape of the back surface of the nail body or the shape of the finger bone, and the signal which is the feature of the individual reflecting their positional relationship, are measured by the measuring means. Is detected. These data are compared with corresponding data of one or a plurality of individuals registered in advance by the comparing means, and the judging means makes a judgment work based on a certain value, and judges acceptance or rejection. This result is reported as a personal identification result.

According to the personal identification device of the present invention, a signal reflecting an anatomical feature of a fingertip by an ultrasonic beam can be captured as a time delay or intensity of transmission or reflection of an ultrasonic wave. This signal allows the anatomical features of the individual's fingertip to be identified.

According to the personal identification device of the present invention,
A signal reflecting an anatomical characteristic of a fingertip by light, especially near-infrared light that permeates the human body better, can be captured as a change in intensity of transmitted or reflected light, a luminance distribution, or the like. This signal allows the anatomical features of the individual's fingertip to be identified. In any case, the individual can be identified by comparing the anatomical feature of the fingertip of the individual registered in advance with the anatomical feature of the fingertip of the newly observed individual.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A personal identification device according to an embodiment of the present invention will be described with reference to FIGS. First, the overall overall configuration of the personal identification device according to the present embodiment will be described with reference to FIG.

The personal identification device according to the present embodiment detects the placement of the fingertip on the measurement probe 4 and starts the measurement when measuring the anatomical feature of the fingertip of the person. It has a switch 2. The switch 2 may be a mechanical switch pressed by a fingertip or a switch that is turned on when the fingertip approaches the measurement probe 4 by various non-contact sensors. The on / off signal from the switch 2 is output to the control circuit 6, and when the on signal is output from the switch 2 to the control circuit 6, the control circuit 6 sends a measurement start command to the measurement means signal processing circuit 8. . Upon receiving the command, the measurement means signal processing circuit 8 receives a measurement signal based on the anatomical feature of the fingertip obtained from the measurement probe 4 that performs measurement using an ultrasonic beam or near-infrared light.

The received measurement signal is sent to the feature extraction unit 10 as measurement data through predetermined signal processing, and the feature amount is extracted. The extracted feature amount is sent to the comparison means 12 and the storage means 14. The feature amount stored in the storage unit 14 is used for personal identification in the next measurement.
The amount of extraction sent to the comparison means 12 is stored in the storage means 14.
Is compared with a predetermined feature amount already stored in the storage unit, and the comparison result is input to the determination result signal output unit 16 to determine the individual identification, and the determination result 18 is output.

Next, the anatomical features of the fingertip measured by the personal identification device according to the present embodiment and the advantages of using the features will be described with reference to FIGS. FIG. 2 schematically shows the structure of a fingertip of a person when viewed from the side. At the fingertips of the human body, blood vessels (not shown) that can be separated from other tissues by light or ultrasonic waves due to absorption and flow of infrared light by hemoglobin, differences in acoustic impedance, absorption wavelength and scattering of light There are tissues such as the distal phalanx 26 and the nail 30 which can be easily separated due to the difference between them. There are individual differences in the shapes of these tissues and the mutual positional relationship, and these are powerful information for identification.

The anatomical features of the fingertip include subcutaneous blood vessels (arteries and veins), nerves, fascia, muscles, sweat glands, not shown.
Hair root, bone, cartilage, or the back of nail body 30, lower nail skin 2
0, a nail bed 22, a nail base 24, a nail matrix 34, and the like, which are features of a tissue that cannot be observed from the outside in a normal environment. Such anatomical features can be attributed to the epidermis (eg, the keratinized layer 36 of the epidermis).
And the skin part 38), which is deeper than the keratinized layer, is less affected by illness and contamination, and has a lower environmental and psychological state than methods using fingerprints or utterances whose data collection depends on the state of sweating. Hard to be affected. Also, unlike the upper nail body 32 on the surface of the nail body 30, personal characteristics are not lost due to nail polish, remover, nail polish and the like.

The fingertip is usually not covered with clothing and the like and is always exposed. Also, unlike being unconsciously photographed with a camera or the like, the user can actively receive the judgment operation himself, and there is a sense of security. The fingertips stand out in the human body in such a way that they reflect their will in this way, and have both bones and nails, which are tissues with significantly different acoustic impedance and optical characteristics from other tissues, in close proximity . Further, the fingertip is a small part in the human body, and therefore, the measuring device is easily reduced in size.

Tissue under the fingertip has many features that make it possible to identify an individual, similar to a fingerprint. For example, the distal phalanx 2
In 6, the length, cross-sectional shape, cross-sectional area, volume, distance from the body surface (epidermal surface or nail) and the like have individual differences and can be used as identification information. As described above, the nail has an overall curvature that cannot be artificially changed by manicure or the like, and a pattern of a plurality of longitudinally extending striated lines on the back surface of the nail body 30 reflecting the shape of the skin portion forming the nail bed 22 Hardly changes.

FIG. 3 shows an example of actual measurement of the inter-tissue distance of the fingertip. In this actual measurement example, the thickness of the nail body 30 is about 0.5 mm.
29 mm, the thickness of the stratum corneum 40 is about 0.42 mm,
The distance between the distal end of the distal phalanx 26 and the stratum corneum 40 is
At the horizontal, vertical, and their 45 ° measurement positions, they are approximately 3.2 mm, 6.3 mm, and 4.2 mm, respectively. In the figure, the distance between the nail body 30 and the stratum corneum 40, that is, the distance between the vertical straight lines passing near the distal end of the distal phalanx 26 is about 9.2 mm. In the fingertip shown in FIG. 3, it is effective to use the data of the external shape of the fingertip of the nail body 30 and the stratum corneum 40 and the data of the shape and positional relationship of the bones, blood vessels, and the nail body 30. Since the skin other than the nail body 30 is soft, it is necessary to allow for an error of the shape deformation. In order to suppress such an error, a method may be adopted in which a pressure sensor or the like is provided at a place where the fingertip comes into contact, and the measurement start timing is always maintained at a constant deformation amount.

Next, the measurement object will be described in detail. FIG. 4 shows a fingertip cross section of a surface including the nail and the distal phalanx 26. The nail extends but the shape of the cross section perpendicular to the direction in which the nail extends does not change much in adults. As described above, the shape and surface state of the back surface of the nail are artificially changed by manicure or the like.
2 is untouched. The curvature of the entire nail in this cross section and the shape of the numerous fine lines of the nail bed small ridge 42 running vertically on the front and back of the nail body 30 are stable if healthy. If near-infrared light or ultrasonic waves are used, the shape information can be obtained from the back surface of the nail body 30, that is, from the abdomen of the fingertip. Since the nail tip is often contaminated with foreign matter on the back, the ultrasonic beam or near-infrared light avoids the tip as shown in FIG.
The light enters from the side of the finger pad (arrow B in the figure) or the tip of the fingertip (arrow A in the figure).

Particularly effective parameters are, as shown in FIG. 6, the curvature R of the entire claw body 30, the number of filaments on the back surface of the claw body 30, and the pitch of the filaments on the back surface of the claw body 30. The linear shape on the back surface of the nail body 30 reflects the shape of the nail bed small ridge 42. Therefore, the nail body 30
Even if the shape of the surface of the nail bed 22 is measured instead of the shape of the back surface, the same information can be obtained. The geometric information from the back surface of the nail body 30 or the nail bed 22 hardly fluctuates due to pressure or the like. In particular, the linear shape of the back surface of the nail body 30 or the number and pitch of the nail bed small ridges 42 are extremely stable, and are hardly affected by injury or disease or contamination, so that they are suitable as parameters for personal identification.

Like the nail, the distal phalanx 26 of the fingertip has a number of geometric features. As shown in FIGS. 2 and 3,
The distal phalanx 26 is the end point of the skeleton, and its tip is in contact with the subcutaneous tissue. The distance from the surface of the stratum corneum 40 is only about 3 mm at the tip, and 5 to 6 m even from the finger pad side.
m. Therefore, much information can be obtained from the characteristic tip shape. The longitudinal cross-sectional shape of the distal end of the distal phalanx 26 is generally an oblong shape as shown in FIG. As shown in FIG. 7, the width a in the horizontal direction, the width b in the vertical direction, and the curvature R of the distal phalanx 26 can be used as effective parameters.
A measurement example of the nail, the bone, and the positional relationship between the nail and the bone will be described later.

Means for observing the subcutaneous tissue include a method using X-rays and an MRI (Ma
genetic Response Imaging)
Although it is known, it is difficult to use it for personal identification device technology in terms of security and device size. In this regard, the method using ultrasonic waves or light is excellent. In addition, when the purpose is to isolate individual differences in a limited area such as a fingertip, unlike an image diagnostic apparatus for detecting a morphological abnormality or a lesion, it is not necessary to perform a visualization process. Absent. For example, it suffices if only the individual difference in the delay time of the reflected signal from the tissue boundary can be detected.

In order to find the anatomical individual difference of the fingertip, it is needless to say that the resolution of the detecting means is preferably high. A resolution of at least mm or less is required. The higher the frequency, the greater the absorption due to the organization of the ultrasound,
Directivity improves as the frequency increases. That is, if a high frequency is used to increase the resolution, the attenuation is so strong that it becomes difficult to detect a deep tissue. There is also a limitation on the intensity of ultrasonic waves that can be used, that is, 0.1 W / cm ² or less, which is below the reversible heat action range. At 1 to 5 W / cm ² , a heating action occurs, and when it exceeds 10 W / cm ² , cells are destroyed by cavitation.

For these reasons, the frequencies available to living organisms are usually in the range of 1 to 15 MHz. Here, since it is used for tissue separation in a limited area of the fingertip, the penetration depth may be about several millimeters to about 10 mm, while the resolution (longitudinal resolution) along the ultrasonic beam is 1 mm or less. Is required. Therefore, the frequency used is 3.5 to 15 MHz.
z is desirable. A transmission method consisting of an oscillator that oscillates ultrasonic waves and a receiving probe that opposes the fingertip, and a reflection that places the oscillator and the receiving probe on the same side of the fingertip and detects the reflected signal from the tissue boundary Either method may be used. In the case of the reflection method, oscillation is performed in a pulse shape, and individual differences can be known from a delay of a reflection signal from a tissue boundary.

When information from the back of the bone or nail is used, the acoustic impedance of these is significantly different from other tissues, and most of the sound waves are reflected. In ultrasonic diagnosis, the presence of such a strong reflector causes acoustic shadows and multiple reflections, which makes reading difficult. However, in this case, it is sufficient if the difference between the signals is captured, and since the imaging process is unnecessary, information from bones and nails can be positively used.

FIG. 8 shows an example of the configuration of a personal identification device when a reflection method for reflecting ultrasonic waves is used. 8, components having the same functions and functions as those of the personal identification device shown in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted. The ultrasonic beam from the measuring probe 4 is on the ventral side of the fingertip (opposite the nail)
Emitted from. At this time, water or a jelly-like liquid is usually used in order to prevent reflection of ultrasonic waves by an air layer between the body surface and the ultrasonic oscillator of the measurement probe 4. For this purpose, a water adding device 50 is provided. However, in the case where the close contact with the oscillator can be maintained by the sweating action on the hand surface, the liquid is unnecessary.
A method of moistening the fingertip with water is effective for stabilizing the operation and convenience in use. Further, a mechanical scanning system 52 for scanning the ultrasonic beam in the direction in which the fingertip extends is provided, and is controlled by the control circuit 6.

Since a medical ultrasonic diagnostic apparatus usually detects a slight difference in acoustic characteristics between tissues other than bones, it is necessary to catch a relatively large echo signal to an extremely weak signal. Therefore, a logarithmic amplifier or the like that compresses this large level difference is used. In addition, a digital scan converter or the like is incorporated to create a television video signal for image diagnosis. On the other hand, here, it is sufficient that only information from nails and bones is accurately obtained by using ultrasonic waves. As described above, these acoustic impedances are very large compared to the surrounding tissue (1 to 10 MHz).
On average, z is about 5.3 × 10 ⁶ kg / m ² / s for bone
ec. In contrast, the muscle mass is 1.73 × 10 ⁶ kg / m ²
/ Sec. Fat is 1.43 × 10 ⁶ kg / m ² / se
c. , Blood was 1.63 × 10 ⁶ kg / m ² / sec. ), The sound pressure reflectance is very large compared to other organizations.

Therefore, here, basically, a transmitting circuit 56 for scanning the ultrasonic beam emitted from the measuring probe 4 in a direction orthogonal to the direction in which the nail extends, and transmitting a signal for performing the focusing, and a measuring circuit A simple circuit configuration including only the detection circuit 58 that detects the measurement signal from the probe 4 is sufficient. In this case, a weak signal from a tissue having a similar acoustic impedance is ignored. Further, an amplifier circuit 54 for correcting the attenuation of the echo signal from the deep portion, for example, a circuit for temporally increasing the amplification degree after the start of reception may be added between the measurement probe 4 and the detection circuit 58. The output signal from the detection circuit 58 passes through the A / D converter 60,
The signal is converted from an analog signal to a digital signal and input to the feature extracting unit 10.

FIG. 9 shows a basic configuration example of the pulse echo method. In this figure, echo signals A and B from nails and bones are shown. The signal waveform A of the output signal output from the measurement probe 4 to the amplification circuit 54 is obtained as a pulse train whose amplitude changes as a response to the pulse train emitted from the measurement probe 4 to the fingertip. Further, the signal waveform B output from the detection circuit 58 becomes a signal that can identify the attenuation of the pulse amplitude, the length of the peak interval of the pulse train, and the like.
Sent to The distance between the peaks of this signal reflects, for example, the distance from the back surface of the nail body 30 and the surface of the distal phalanx 26 described above. As the scanning method of the ultrasonic beam, linear scanning, sector scanning, offset sector scanning and the like are used. The scanning mechanism may be mechanical or electronic.

FIG. 10 shows an example of measurement by sector scanning.
Here, in addition to the sector scanning, mechanical scanning is performed in the direction of the arrow and in the direction of the long axis of the finger. At the tip of the finger, as shown in FIG.
Although only information from 0 can be obtained, an echo signal from the distal phalanx 26 can be obtained at a distance of about 3 mm.
When the signal from the distal phalanx 26 is obtained and the mechanical scanning is further performed in the direction of the arrow by about 6 mm, the signal from the nail 30 passes through the nail cage and disappears. While both signals from the distal phalanx 26 and the claw body 30 are being detected, the positional relationship between the two is stable, so that distance information can always be obtained stably. From this, the width of the distal phalanx 26, the distance between the distal phalanx 26 and the back surface of the nail body 30, and the curve information of the entire back surface of the nail body 30 are obtained. However, here, the time until the echo from the bone or nail returns or the time difference between the echoes is important, and it is not important to obtain information such as the anatomically correct positional relationship therefrom. The timing of the sector scanning (scanning of the finger cross section) and the scanning in the finger long axis direction, and the reception time of each echo signal are feature amounts.

When collecting information from the nail, an ultrasonic wave or near-infrared beam is incident from the abdomen of the fingertip or the tip of the fingertip as shown in FIG. 5 described above. At this time, for example, as shown by an arrow in FIG. By scanning the beam in the longitudinal direction of the finger, the distal phalanx 2
6, and positional relationship information between the distal phalanx 26 and the nail 30 can also be obtained. As typical positional relationship information, the distal phalanx 2
6- Distance between the back surfaces of the nail bodies 30 (distances d, h, j, f in the figure)
FIG. 11 shows a method for obtaining the distal phalanx width (a, b). In FIG. 11, by scanning the ultrasonic beam from the measurement probe 4, the distances c, c + d,
Since g, g + h, e, e + f, i, i + j can be measured, a desired distance can be calculated from them. In addition, the distal phalanx 2
It is possible to obtain information such as the shape of the six distal end portions and the distance from the distal end portion of the finger to the top of the distal phalanx 26.

As another method for safely measuring tissue in a living body, a technique using light is known. Wavelength 700
Near-infrared light having a wavelength of ２０００2000 nm, particularly 780-1400 nm, has low optical absorption of hemoglobin and water, and can penetrate the tissue well. As a tomographic apparatus using light in this region, for example, a confocal scanning microscope (CLS)
M) and OCM (Optical Coherence)
Microscope). These principles and the improved OCM tomography apparatus are described in detail in, for example, JP-A-8-252256.

The basic procedure for using near-infrared light is the same as that for ultrasonic waves. Further, in the case of near-infrared light, the distance resolution can be higher than that of ultrasonic waves, and the beam can be narrowed. Therefore, a finer structure such as the linear pattern information on the back surface of the nail body 30 can be used.
In the case of performing a scan similar to that in FIG. 10 described above, in addition to the information from the nail body 30 and the distal phalanx 26 described above, the tip of the fingertip that can only obtain information from the back surface of the nail body 30 (in the case of such a scan, Even during scanning of about 3 mm from the tip), the line pattern information of the back surface of the nail body 30 or the nail ridge 42 shown in FIG. 6 can be obtained. In the confocal scanning type, it is possible to read out the projections of the linear pattern as a luminance pattern. In addition to the above-described features, the number of luminance peaks and the distance between the peaks can also be used as the features.

At the time of registration, these feature information together with the ID number and the like are recorded on a storage medium such as a disk device, an IC card, or a magnetic card. At the time of collation, the stored data is called with an ID number or the like, and is compared with the input data at the time of collation. At the time of comparison, a predetermined allowable range may be provided in consideration of a slight fluctuation at the time of data input. In some cases, an accident such as an operation error or misalignment may occur at the time of collation, so that even if the comparison result is not determined to be the person, a setting may be made to allow a predetermined number of retries. In the case where the number of registered data is small, an identification process for comparing the total number of registered data without using the ID number may be used.

[0037]

As described above, according to the present invention, since personal identification is performed using a fingertip, unlike a method of recording a face image remotely with a camera or the like, there is an active operation feeling and monitoring. There is no danger of being stealing patterns from remote locations. In particular, as in the present invention, if the anatomical feature, that is, the feature of the subcutaneous tissue, is used instead of the appearance of the fingertip, it cannot be measured with ordinary equipment, and it is possible to know even what feature is being captured. It is almost impossible to forge because of the difficulty. In addition, there is no negative image such as a criminal investigation image or a surveillance image such as a fingerprint. Furthermore, since the measurement is at the fingertip, unlike the eyes, there is no psychological resistance such as fear. The anatomical features, particularly the nails and bones of interest here, do not change according to the user's psychological state and have no deformation, so that they can always be measured stably. Ultrasonic waves and light, particularly near-infrared light, can detect signals reflecting anatomical features without adversely affecting the human body.

The personal identification device according to the present invention is almost impossible to forge as described above, does not give a psychological burden or resistance to the user, and is subject to physical restraint conditions during use. It is extremely small, and is not easily affected by the user's psychological condition or health condition, and can always be stably identified.

[0039]

[Brief description of the drawings]

FIG. 1 is a diagram showing an overall schematic configuration of a personal identification device according to an embodiment of the present invention.

FIG. 2 is a schematic diagram of an organization of a human fingertip.

FIG. 3 is a diagram showing an example of an inter-organization distance of a fingertip of a person;

FIG. 4 is a diagram illustrating an example of a fingertip cross section (a surface including a nail and a distal phalanx).

FIG. 5 is a diagram illustrating a direction in which a measurement beam such as an ultrasonic wave or light is incident on a fingertip in the personal identification device according to the embodiment of the present invention.

FIG. 6 is a diagram illustrating an example of a nail shape measurement target;

FIG. 7 is a diagram showing an example of measuring the shape of the distal phalanx.

FIG. 8 is a diagram showing an overall configuration of a personal identification device using an ultrasonic reflection method according to an embodiment of the present invention.

FIG. 9 is a diagram showing an example of a signal waveform in each circuit of the personal identification device using the ultrasonic reflection method according to one embodiment of the present invention.

FIG. 10 is a diagram showing an example of fingertip scanning by sector scanning in the personal identification device using the ultrasonic reflection method according to one embodiment of the present invention.

FIG. 11 is a diagram showing a measurement example of positional relation information between the distal phalanx and the nail in the personal identification device using the ultrasonic reflection method according to one embodiment of the present invention.

[Explanation of symbols]

 2 Switch 4 Measurement probe 6 Control circuit 8 Measurement means signal processing circuit 10 Feature extraction unit 12 Comparison means 14 Storage means 16 Judgment result signal output means 18 Judgment result 20 Lower nail skin 22 Nail bed 24 Nail base 26 End phalanx 30 Claw body 32 On Claw body 34 Nail matrix 36 Keratinized layer of epidermis 38 Epidermis part deeper than keratinized layer 40 Stratum corneum 42 Nail base small ridge 50 Watering device 52 Mechanical scanning system 54 Receiving circuit amplifying circuit 56 Transmitting circuit focusing circuit 58 Detection Circuit 60 A / D converter

Continuing on the front page (72) Inventor Tadashi Shimizu 430 Border, Nakaicho, Ashigarakami-gun, Kanagawa Prefecture Green Tech Inside Fuji Xerox Co., Ltd.

Claims (7)

[Claims] 1. A measuring means for measuring an anatomical characteristic of a fingertip of a person, a comparing means for comparing an output value from the measuring means with a stored value stored in advance, and according to a comparison result by the comparing means. A personal identification device comprising: a determination unit that generates a personal identification result. 2. The personal identification device according to claim 1, wherein said measuring means detects at least a signal reflecting a shape of a back side of a nail body of said fingertip. 3. The personal identification device according to claim 1, wherein said measuring means detects at least a signal reflecting a bone shape of said fingertip. 4. The personal identification device according to claim 1, wherein said measuring means detects at least a signal reflecting a positional relationship between a fingertip bone and a nail. apparatus. 5. The personal identification device according to claim 1, wherein said measuring means has an ultrasonic oscillation means for emitting an ultrasonic beam into said fingertip. . 6. The personal identification device according to claim 1, wherein said measurement means includes illumination means for irradiating light into said fingertip. 7. The personal identification device according to claim 6, wherein said illumination means emits near-infrared light.