JPS63221483A - Method for detecting ruggedness information - Google Patents

Abstract

PURPOSE:To easily and correctly evaluate the rugged surfaces of a fingerprint, etc., by using a finger holding tool to position the finger. CONSTITUTION:When a finger 9 is loaded to a finger holding tool 12 equipped with an inclined surface 15, three contact detecting devices 16 provided at the inclined surface 15 and an aperture 14, in response to a detecting output by a detecting device 6, a fingerprint sensor 2 of a rugged surface detecting device rises, and the rugged surface contacting part is brought into contact with a projecting part 9a and a recessed part 9b of the finger 9. In this condition, it is not necessary to execute the centering for positioning the finger by a semiconductor laser 3, a hologram 7 and a camera 4 for detecting, the distortion of the fingerprint of the image pick-up object is eliminated and the evaluation of the rugged surfaces of the fingerprint, etc., can be executed easily and correctly.

Description

[Detailed Description of the Invention] [Summary] In an unevenness information detection device that detects a fingerprint of a finger pressed against an uneven surface contact portion of a transparent flat plate, the uneven surface for detection of a detected object is detected from an opening of a detection object holder. Imaging with excellent reproducibility is possible by pressing the uneven surface detector against the uneven detection surface of the object after contacting the object to be detected with the object holder so that the object holder protrudes. I made it.

[Industrial application field]

The present invention relates to an unevenness information detector, and particularly to a fingerprint detection device for detecting fingerprints.

As the information society progresses, stakeholders are becoming increasingly concerned about how to maintain the airtightness of information processing systems, for example, how to ensure system security as computers are introduced into a wide range of social systems. ing.

Therefore, as a means of verifying the identity of a person when entering a computer room or using a terminal, a fingerprint detection device that directly optically detects fingerprints, which differ from person to person and is safe from loss or theft, has been developed. Appeared.

C. Prior Art FIG. 4 is a schematic side view showing the main parts of a conventional fingerprint detection device (unevenness information detection device).

In FIG. 4, the fingerprint detection device 1 includes a semiconductor laser 3 and a detection camera (detection image sensor) below the fingerprint sensor 2.
4 is provided. The fingerprint sensor 2 has a pair of holograms 7 provided on the lower surface of a transparent flat plate 6 made of optical glass, and the detection camera 4 faces the holograms 7.

In such a device 1, a finger 9 is pressed against the finger contact portion of the fingerprint sensor 2, and the contact portion between the transparent flat plate 6 and the finger 9 is illuminated with illumination light 10 emitted from the semiconductor laser 3 that passes through the transparent flat plate 6. .

Then, the illumination light 1O irradiated to the part opposite to the recess 9b due to the fingerprint of the finger 9 is transmitted upward to the transparent flat plate 6 and reaches the recess 9b.
On the other hand, the illumination light 10 irradiated onto the part of the fingerprint in contact with the convex part 9a is scattered at the contact interface, and a part of the illumination light 10a propagates through repeated total reflection and is emitted downward from the detection hologram 7.

As a result, a fingerprint image that is bright at the convex portions 9a and dark at the concave portions 9b is captured by the detection camera 4.

[Problem that the invention seeks to solve]

FIG. 5 ((), (0)l (II) schematically shows a fingerprint image displayed on a monitor of a conventional fingerprint detection device.

In the device 1, the finger contact portion of the fingerprint sensor 2 indicates the pressed area of the finger 9, and does not position the pressed finger 9. Therefore, the pressing position of the finger 9 has to be adjusted (centered) while looking at the monitor, but in general, when the finger 9 is removed from the contact area, the monitor image disappears, so the finger 9 must be rubbed without removing it. move.

Therefore, the concentric fingerprints shown in Fig. 5 (a) are correct, as shown in Fig. 5 (υ), (//
As in 1), there is a problem in that the fingerprints become closer on the side where the finger 9 is moving and widen on the opposite side, resulting in "image distortion," which impairs accurate evaluation of the fingerprints.

[Means for solving problems]

In the uneven detection device of the present invention aimed at eliminating the above-mentioned problems, as shown in FIG. The detected object (hand and finger) holder 12 is provided with an opening for detecting the detected object 9.
and move the uneven surface detector (fingerprint sensor) 2 toward the holder 12 to detect the uneven surface (fingerprint) detection part 17 of the uneven surface detector 2.
It is characterized in that it is pressed against the uneven detection surface protruding from the opening.

[Effect]

According to the above means, the detected object is positioned by contacting the detected object holder, and the conventional adjustment for moving the detected object becomes unnecessary. Therefore, imaging without "image distortion" is possible, and evaluation of uneven surfaces such as fingerprints becomes easier and more accurate.

〔Example〕

EMBODIMENT OF THE INVENTION Below, the uneven|corrugated information detection apparatus (fingerprint detection apparatus) by the Example of this invention is demonstrated using drawing.

FIG. 1 ((), (0) is a schematic side view for explaining the main part configuration and operation of a fingerprint detection device according to an embodiment of the present invention, and FIG. 2 is a view taken in the direction of arrow A in FIG. 1. , FIG. 3 is a perspective view of the finger holder of FIG. 1.

In FIG. 1, in which the same reference numerals are used for parts common to those in FIG. 4, the fingerprint detection device 11 includes a finger (detection object) holder 12 supported almost horizontally by appropriate means, a fingerprint sensor 2. Semiconductor laser 3. A detection camera 4 is arranged in the same manner as before.

The finger holder 12 is U-shaped in plan view as shown in FIG. 3, and has an opening 14 through which the fingerprint surface (detection uneven surface) of the finger 9 consisting of a convex portion 9a and a concave portion 9b projects downward. 12 is formed into a slope 15 whose inner edge widens upward, and contact detectors 16 are provided at three locations on the slope 15. Therefore, when the finger 9 is mounted on the finger holder 12, the slope 15
positions the finger 9, and the contact detector 16 whose three peripheral portions of the fingerprint surface are sloped surfaces 15 detects the placement of the finger 9.

The fingerprint detection device 11 configured in this way has a fingerprint sensor 2.
When the finger 9 is mounted on the holder 12 of the holder 12, and the contact detector 16 detects the mounting of the finger 9, the fingerprint sensor 2 moves up and presses the finger contact portion 17 against the fingerprint surface of the finger 90.

Then, the illumination light 10 emitted from the semiconductor laser 3 that passes through the transparent flat plate 6 illuminates the finger contact area from within the transparent flat plate 6, and a portion 1 of the illumination light 10 irradiated onto the area in contact with the fingerprint convex part 9a.
0a propagates through repeated total reflection, and the detection hologram 7
It emits downward from.

As a result, a fingerprint image that is bright at the convex portions 9a and dark at the concave portions 9b is captured by the detection camera 4.

〔Effect of the invention〕

As explained above, according to the present invention, since the finger holder is used to position the finger, the conventional centering is not necessary, and imaging is facilitated.
This has the effect of eliminating "deflection" and achieving accurate evaluation.

[Brief explanation of the drawing]

Fig. 1 shows a fingerprint detection device according to an embodiment of the present invention, Fig. 2 shows a view taken from arrow A in Fig. 1, Fig. 3 shows a hand holder shown in Fig. 1, and Fig. 4 shows a conventional fingerprint detection device. , Figure 5 shows the "distortion" of the monitor image. In the figure, 2 is a fingerprint sensor (uneven surface detector), 9 is a finger (detected object), 9a is a convex part of the finger 9, 9b is a concave part of the finger 9, 10 is a laser beam, 10a is a reflected light, 11 12 is a fingerprint detection device (unevenness information detection device), 12 is a finger holder (detected object holder), 14 is an opening, and 17 is a finger contact portion (uneven surface contact portion). (b) Kibatsu a rib two great force meter Ikuri t = r34 Ummon Mokken Min = #L thing) Kuni (a) (b) (c)
Seven Niku Wataru (no゛(nafu〃'))

Claims (1)

[Claims] The detected object (9) is brought into contact with a detected object holder (12) provided with an opening (14) through which the uneven detection surface of the detected object (9) protrudes and the peripheral part of the detected uneven surface comes into contact. , the uneven surface detector (2) is moved toward the holder (12), and the uneven surface detection portion (17) of the uneven surface detector (2) is moved toward the opening (14).
A method for detecting unevenness information, characterized in that the uneven detection surface is pressed against the uneven detection surface protruding from the surface.