JPS6220081A - Method and device for collating individual - Google Patents

Abstract

PURPOSE:To improve the resolution of an image pickup, to shorten the collation processing time and to obtain an individual collating device having a high performance, by moving an image pickup element for detecting a pattern, so as to be opposed to pattern information from an object to be inspected. CONSTITUTION:When an illuminating light 8 is irradiated and a finger 6 is made to abut on a detector 21 by a suitable pressing force, an image pickup element 9' photographs the reduced image of the detector 21. Next, a CPU 25 calculates the abutting position of the finger 6 in the reduced image, moves a stage 11 so that the image pickup element 9' is opposed to the calculated position, that is to say, an image pickup element 9 is positioned on the same axis as a scattered light 8a. As a result, the image pickup element 9 photographs the fingerprint pattern of an unmagnification image and a collating circuit 3 which has collated an image pickup pattern and a pattern registered in a collating dictionary forms collating information.

Description

[Detailed Description of the Invention] [Summary] In a method and device for collating and identifying individuals using fingerprints, etc., the resolution of the imaged pattern is improved by aligning the subject and the image sensor, thereby increasing the performance of the device. , and the matching time is shortened.

[Industrial application field]

The present invention relates to a personal verification system, and particularly to a method for personal verification that detects uneven patterns such as fingerprints and palms, and improvement of the device.

BACKGROUND OF THE INVENTION As the information society progresses, various technologies related to maintaining the confidentiality of information processing systems are being developed. For example, when controlling access to a computer room, conventional I
In place of the D-card, personal verification systems are beginning to be introduced in which each individual's fingerprints are registered in advance and verified upon entering the room, but since they are targeted at particularly important equipment, further improvements in performance are desired. It is rare.

[Conventional technology]

FIG. 5 is a block diagram showing a conventional personal verification device.

In FIG. 5, a conventional personal verification device that incorporates fingerprints as personal information uses a fingerprint detector as a personal information input means, and is composed of a fingerprint detector 1, an information verification dictionary 2, and an information verification circuit 3. has been done. A dictionary 2 for checking information on a card or the like stores fingerprints registered in advance via a fingerprint detector 1.

When a fingerprint is input from the fingerprint detector 1 for personal verification,
The input fingerprint and the registered fingerprint are compared and verified by the information verification circuit 3, and it is determined whether the verification person is a registered person.

Note that a hologram, which is a light diffraction element, diffracts incident light by a certain angle and emits it. FIG. 6 is a diagram showing the principle of a fingerprint detector using a total reflection type hologram.

In FIG. 6, the fingerprint detector 1 consists of a glass 4 and a hologram 5, and incident light 8 from an air layer 7a in contact with the hologram 5 is diffracted by a diffraction grating stripe 5a formed on the hologram 5 and enters the glass 4. The incident angle of the light incident on the glass 4 depends on the inclination angle of the lattice stripes 5a, but if the angle θ at which the incident light on the glass 4 is incident on the interface between the glass 4 and the air layer 7b exceeds a critical angle, and air Ji7
Total reflection occurs at the interface with b.

Therefore, when an uneven object (for example, a finger) is brought into contact with the interface of the glass 4, the incident light 8 is totally reflected by the concave portions of the uneven surface, but on the other hand, the light is scattered by the convex portions of the object. can be observed as optical fringes.

FIG. 7 is an enlarged view of a part of the fingerprint detector 1 in which a finger is brought into contact. When the finger 6 is brought into contact with the glass 4 of the detector 1, the above-mentioned total reflection condition is maintained in the recess 6b due to the fingerprint. , light scattering occurs in the convex portion 6a.

Therefore, if an image sensor is used, an image of the unevenness of the finger 6, that is, a fingerprint image can be obtained.

[Problem that the invention seeks to solve]

The above-mentioned personal verification method and device are used as means for determining whether or not a subject is the registered person by detecting a fingerprint pattern or the like and comparing it with a registered pattern.

For such applications, it is sufficient that the entire specimen such as a fingerprint has a width of about a few squares, but conventional pattern detectors (fingerprint detectors, etc.) Considering the deviation of the contact position, etc., the contact surface of the test part is sufficiently wider than the required height, for example, about several tens of degrees,
The image processing is performed over the entire area of the contact surface.

Therefore, if a fine pattern is to be identified over the wide area, the equipment becomes expensive and it becomes difficult to ensure the resolution of the fine pattern, so there has been a strong desire for improvement.

Means for Solving Problem C] FIG. 1 is a conceptual diagram showing the basic configuration and connection relationship between the configurations, in which the present invention is applied to the above-mentioned fingerprint verification device.

The above problem is solved by detecting the contact position of the subject 6 that is in contact with the detector 1 that detects the uneven patterns 6a and 6b, and moving the image sensor 9 of the pattern based on the position information so that it faces the detector 1. and further characterized in that the position information is detected from a reflected image of the subject 6, or the position information is detected from a projected image of the subject 6, and a detector 1 that detects the uneven patterns 6a and 6b of the subject 6; and a stage 11 that is movable in a plane substantially parallel to the detector 1.
, an ↑layer image element 9 mounted on the stage 11 to image the detection pattern of the moxibustion device 1, a position detection means 12 for detecting the position of the corresponding contact, and a position detection means 12 to move the stage 11 based on information from the position detection means 12. A glass substrate (2) is further provided with a control circuit 13 for causing
2), a first hologram (23) for detecting the uneven patterns 6a, 6b, and a first hologram (23)
) for detecting the position of said abutment at a diffraction angle different from
The detector 1 and the position detecting means 12 are integrally formed by stacking the holograms (24), or the position detecting means 12 is a projected image position imaging element ( 31) is solved by a personal verification device.

[Effect]

According to the above means, the image sensor 9 images the verification pattern of the subject 6 after moving to the position from which the detection information from the subject 6 is emitted. Therefore, compared to the required imaging area, the detector 1
Even if the abutting surface of the object 6 is sufficiently wide, it is only necessary to image a limited area as required, rather than imaging the entire surface of the abutting surface. It becomes possible to shorten the time required.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the method and apparatus of the present invention will be described below with reference to the drawings.

FIG. 2 is a block diagram showing the main structure of an embodiment of the method and apparatus of the invention, and FIG. 3 is a block diagram showing the main structure of another embodiment of the method and apparatus of the invention. FIG. 4 is a diagram showing a projected image of the subject in the embodiment described above, and in each figure, the same reference numerals are used for parts common to the previous figure.

In FIG. 2, 21 is a detector equipped with the function of detecting a fingerprint pattern and a fingerprint contact position; 25 is a CPU; Alternatively, an image pickup element 9' located at an arbitrary position and in contact with the subject (finger) 6 is shown by a dotted line.

The detector 21 has a first hologram 23 and a second hologram 24 that have different selectivities with respect to the traveling direction of the illumination light 8.
are laminated on the lower surface of the glass substrate 22. The holograms 23 and 24 are, for example, as shown by the dashed line in the figure, a same-magnification image of the first scattered light 8a that is emitted without being diffracted almost directly below the finger 6, and a 1-magnification image of the first scattered light 8a that is diffracted by the hologram 24 and shifted to the side. A diffraction grating that forms a reduced image by the second scattered light 8b emitted at the position is formed in each.

Therefore, the illumination light 8 is not diffracted by the hologram 24 but is diffracted by the hologram 23, and the illumination light 8 is incident on the glass/air interface on the upper surface of the substrate 22 at a critical angle or more.

Then, a portion 8b of the scattered light providing the fingerprint information of the finger 6 is not diffracted by the hologram 23, but is diffracted by the hologram 24 and emitted. In addition, the other part 8a is a hologram 23
and 24, emitted from the fingerprint sensor 21,
A same-size image of the fingerprint pattern with scattered light 8a and scattered light 8b
A reduced image including the fingerprint pattern is formed.

In such a verification device, the illumination light 8 is irradiated and the detector 21
When the finger 6 contacts with an appropriate pressing force, the image sensor 9' photographs a reduced image of the detector 21, the CPU 25 calculates the contact position of the finger 6 within the reduced image, and captures the image at the calculated position. The stage 11 is moved so that the element 9' faces, that is, the image pickup element 9 is positioned coaxially with the scattered light 8a.

Then, the image sensor 9 photographs a life-size image of the fingerprint pattern,
The matching circuit 3 that matches the captured pattern with the pattern registered in the matching dictionary provides matching information.

Next, a personal verification device according to another embodiment of the present invention will be explained using FIG.

In FIG. 3, 31 is a finger 6 that is in contact with the fingerprint detector 1.
32 is a frame memory;
33 is a contact center determining circuit for the finger 6;
The hologram causes total reflection on the upper surface of the detector 1, but some of the illumination light passes through the hologram and is extracted from the detector 1. When the projection image is inputted to the projection image via the frame memory 32, the abutting center determining circuit 32 determines the center line of the width W of the projection image 34 and the center line of the projection image 34, as shown in FIG. The intersection point 35 with the set distance y is calculated, and the position coordinates of the intersection point 35 are output to the CPTJ 25.

Then, the CPU 25 calculates the coordinate difference between the current position of the image sensor 9 according to the information from the X-Y stage control circuit and the position of the intersection 35, moves the stage 11, and moves the stage 11 to move the finger 6 emitted from the fingerprint sensor 1. The image sensor 9 is moved to a position facing the reflected light.

As a result, it is sufficient for the image sensor 9 to have resolution for the required area for detecting the pattern of the finger 6, and the matching circuit 3 only needs to check the required area against the dictionary 2.

Therefore, compared to conventional devices, the resolution of the image sensor 9 can be improved and the verification process can be performed faster.

〔Effect of the invention〕

As explained above, according to the method and apparatus of the present invention, the image sensor for pattern detection is moved so as to be opposite to the pattern information from the subject. Since it is only necessary to take an image, the resolution of the image is improved, the verification processing time is shortened, and the effect of realizing high performance of the personal verification device is remarkable.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the basic configuration of the present invention, FIG. 2 is a block diagram showing the main configuration of an embodiment of the apparatus of the present invention related to the method of the present invention, and FIG. FIG. 4 is a block diagram showing the main configuration of another embodiment of the device; FIG. 4 is a diagram showing a projected image of the subject in the other embodiment; FIG. 5 is a block diagram showing a conventional personal verification device; The figure is a diagram of the principle of a fingerprint detector using a total internal reflection hologram, and FIG. 7 is an enlarged view of a portion of the fingerprint detector shown in FIG. 6 in which a finger is in contact. In the figure, 1.21 is a pattern (fingerprint) detector, 4.22 is a glass substrate, 5.23.24 is a hologram, 6 is a subject (finger), 6a and 6b are irregularities, 9 is an image sensor, 11 12 is a stage, 12 is a position detecting means, 13 is a control circuit, 31 is an imaging element for a projection image, and 34 is a projection image. + A of I Kamaaki's A, Mr. Mizo, is playing with Buhanku, Figure 1, Figure 4, @

Claims (6)

[Claims] (1) Detector (
1) detects the contact position of the subject (6) in contact with the subject (6), and moves the image sensor (9) of the pattern based on the position information to face the detector (1). Matching method. (2) The positional information is detected from a reduced image including the subject (6).
Personal verification method described in section. (3) The personal verification method according to claim 1, wherein the position information is detected from a projected image of the subject (6). (4) A detector (1) that detects the unevenness (6a, 6b) pattern of the object (6) that is in contact with it, and a stage (11) that is movable in a plane substantially parallel to the detector (1). , an image sensor (9) mounted on the stage (11) to image the detection pattern of the detector (1), a position detection means (12) for detecting the position of the contact, and a position detection means (12) for detecting the position of the contact. ) according to the information from the stage (11
) A control circuit (13) for moving the personal verification device. (5) A first hologram (23) for detecting the unevenness (6a, 6b) pattern on the other side of the glass substrate (22) on which the subject (6) is brought into contact; 1st
A second hologram (24) that detects the position of contact at a diffraction angle different from that of the hologram (23) is laminated, and the detector (1) and the position detection means (12) are integrally formed. The personal verification device according to claim 4, characterized in that: (6) The position detection means (12) detects the object (6)
The personal verification device according to claim 4, characterized in that the device is a projected image position imaging device (31) that detects a projected image of a person.