JPS61221883A - Method and device for personal collation - Google Patents

Abstract

PURPOSE:To prevent the misuse of a personal collation system through a subject by collating the personal information supplied via an input means for personal information with the personal information stored previously in an information collating dictionary through an information collating means after confirming that the subject is equal to a living body. CONSTITUTION:A living body detecting means 4 consists of a living body detecting optical system containing the short and long wavelength optical sensors 41 and 42, a comparison voltage generating circuit 43 which produces automatically the comparison voltage corresponding to the output voltage of the sensor 42, a living body discriminating comparator 44 with compares the comparison voltage with the output voltage of the sensor 41 and a touch detecting comparator 45 which detects a contact between a finger 12 and the sensor 42. Here a fact that a subject is a living body is confirmed by the means 4 utilizing the pressure dependance showing that the reflection factore has a big change with pressure of the finger 12 in a <=580nm visible light area which is proper to the human skin. Then a fingerprint supplied from a fingerprint sensor 1 is collated with a fingerprint stored previously in an information collating dictionary 2.

Description

[Detailed Description of the Invention] [Summary] A living body detection means for confirming that the subject is a living body is added to a personal verification system consisting of a personal information input means, a dictionary input means for verification, and an information verification means, and a replica To prevent misuse of the personal verification system by duplicated subjects such as

[Industrial application field]

The present invention relates to a personal verification system, and more particularly to a personal verification device equipped with a living body detection means and a verification method.

BACKGROUND OF THE INVENTION With the advancement of the information society, various technologies related to maintaining the confidentiality of information processing systems are being developed. For example, in place of conventional ID cards, which are often lost or stolen, to manage entry into computer rooms, personal verification systems are being introduced in which each individual's fingerprints are registered in advance and verified upon entering the room.

However, personal identification using fingerprints, etc., is by no means perfect;
For example, by creating a replica of a fingerprint that has been registered in advance, it is possible to pass the inspection by the personal verification system. Therefore, it is desired to develop a personal identification system that can confirm that the subject is a living body.

[Conventional technology]

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

In a conventional personal verification device that incorporates a fingerprint as personal information, a fingerprint sensor is used as a personal information input means as shown in FIG. 5, and the personal verification device includes a fingerprint sensor 1, an information verification dictionary 2, and an information verification device It is composed of 3. Fingerprints registered in advance via the fingerprint sensor 1 are stored in a dictionary 2 for checking information on a card or the like.

When a fingerprint is input from the fingerprint sensor 1 during personal verification, the input fingerprint is compared with a fingerprint registered in advance in the information verification dictionary 2 by the information verification means 3 to determine pass/fail. FIG. 6 shows a principle diagram of a fingerprint sensor used as personal information input means in such a device.

FIG. 6(a) shows a prism-type fingerprint sensor in which a subject, ie, a finger 12, is pressed against the slope of a prism 11, and the light incident from the light source 13 is reflected by the slope of the prism 11, forming an image. A TV camera 14 disposed on the opposite side of the camera 13 takes a picture, and its output voltage is input to the device.

The finger 12 has unevenness 12a and 12b that form a fingerprint, and when the finger 12 is pressed against the slope of the prism 11, the fingerprint recess 12a forms a total reflection surface at the interface between the prism 11 and the air, and the light source 13 reflects the prism. The light incident on the slope 11 is totally reflected at the portion facing the recess 12a of the fingerprint. On the other hand, since the prism 11 and the fingerprint protrusion 12b are in contact with each other, the light source 13
A part of the light incident on the slope of the prism 11 is transmitted through the slope of the prism 11 and is not totally reflected. Therefore, the image formed by the light reflected on the slope of the prism 11 is an image corresponding to the unevenness of the fingerprint, which is composed of totally reflected light and non-totally reflected light, and the difference in contrast of this image is photographed by the TV camera 14. This allows fingerprints to be converted into electrical signals.

6) is a hologram-type fingerprint sensor, in which the subject, that is, the finger 12 is pressed against the top surface of a glass flat plate 15 which also serves as a light guide plate, and the subject 12 is irradiated with a laser light source 16 from the opposite side through the glass flat plate 15. ing. The light transmitted through the glass flat plate 15 is scattered by the surface of the finger 12, but according to Snell's law, all the light scattered by the fingerprint recess 12a is scattered by the glass flat plate 1.
5 and exits into the air layer below. On the other hand, a part of the light scattered by the convex part 12b of the fingerprint passes through the glass flat plate 15 and exits to the lower air layer. The light incident on the interface is totally reflected at the interface and then guided and propagated inside the glass flat plate 15.

A hologram diffraction grating 17 for extracting the light propagating inside the glass plate 15 is formed in a part of the glass flat plate 15, and the light extracted by the hologram diffraction grating 17 is photographed by the TV camera 14 and its output voltage is measured. input into the device.

By guiding the light scattered by the surface of the finger 12 through the glass flat plate 15, it is possible to optically separate the light scattered by the concave portions 12a of the fingerprint from the light scattered by the convex portions 12b of the fingerprint. A fingerprint image with good contrast can be obtained.

Therefore, the difference in contrast of this image can be measured by the TV camera 14.
By photographing the fingerprint, it is possible to convert the fingerprint into an electrical signal.

[Problem that the invention seeks to solve]

The fingerprint sensor shown in FIG. 6 inputs an electrical signal to the device if an image corresponding to the fingerprint is obtained even if the subject is not a living body.On the other hand, in the conventional personal verification device, the fingerprint input from the fingerprint sensor 1 is If the fingerprint matches the fingerprint registered in advance in the information matching dictionary 2, it is determined that the individual who entered the fingerprint and the individual registered in advance are the same person.

However, there is a problem in that by making a replica of a subject that outputs the same information as an already registered fingerprint, such as plaster or soft rubber, and inputting the replica's fingerprint, it is possible to pass the inspection by the personal verification system. there were.

[Means for solving problems]

FIG. 1 shows a block diagram of a personal verification device according to the present invention.

The above problem is caused by the means 41 for detecting light in the short wavelength visible light region of 440 to 580 nm shown in FIG.
means 42 for detecting light in a longer wavelength side light region; comparison voltage generating means 43 for automatically generating a comparison voltage in response to the output voltage of the longer wavelength side light detection means 42; The living body detecting means 4 is provided with a comparing means 44 for comparing the output voltage of the light detecting means 41 on the side, and after confirming that the subject is a living body by the living body detecting means 4, This problem is solved by the personal verification method and device of the present invention, in which the information verification means 3 collates the personal information inputted by the user and the personal information previously stored in the information verification dictionary 2.

[Effect]

As shown in the spectral reflectance characteristics in Figure 2, human skin has a
In the visible light region of 0 nm or less, there is a pressure dependence in which the reflectance changes greatly depending on the pressure.

In FIG. 1, the output voltage of the light detection means 41 on the short wavelength side changes before and after applying pressure to the subject. Therefore, the comparison voltage generation means 43 automatically generates a comparison voltage corresponding to the output voltage of the photodetection means 42 on the long wavelength side, and uses the comparison voltage as a reference before and after applying pressure to the subject. By detecting a change in the output voltage of the light detection means 41, it is possible to detect whether the subject is a person or a replica.

Therefore, after confirming that the subject is a living body using the living body detection means 4, the personal information inputted through the personal information inputting means 1 is compared with the personal information previously stored in the information matching dictionary 2. By doing so, it is possible to prevent the personal verification system from being misused by a duplicated subject such as a replica.

〔Example〕

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 3 is a plan view showing an embodiment of the living body detection optical system,
FIG. 4 is a circuit diagram showing an embodiment of the living body detection means.

In FIG. 3, personal information input means (in this embodiment, a fingerprint sensor is used, hereinafter referred to as a fingerprint sensor) 1 has a means for detecting light on the short wavelength side of 440 to 580 nm (hereinafter referred to as a short wavelength optical sensor) on its upper surface. (hereinafter referred to as a long-wavelength optical sensor) 41;
The short wavelength light sensor 41 has a light emitting diode 411 and a photodiode 412, and the long wavelength light sensor 42 has a light emitting diode 421 and a photodiode 422, and each moves in the direction of the arrow to detect the subject, that is, the finger 12 placed on the fingerprint sensor 1. It is configured so that it is sandwiched from both sides.

In FIG. 4, the living body detection means 4 includes a living body detection optical system consisting of a short wavelength optical sensor 41 and a long wavelength optical sensor 42, and a means for automatically generating a comparison voltage in response to the output voltage of the long wavelength optical sensor 42. A comparison voltage generation circuit 43, a comparison means for comparing the comparison voltage and the output voltage of the short wavelength optical sensor 41, that is, a comparator 44 for biological identification, and a contact detection circuit for detecting that the long wavelength optical sensor 42 has contacted the finger 12. It is composed of a comparator 45.

The living body detection optical system, that is, the short wavelength optical sensor 41 and the long wavelength optical sensor 42 move in the direction of the arrow, and the long wavelength optical sensor 42 moves toward the finger 1.
2, voltage V is output. The reference voltage vI input to the contact detection comparator 45 is compared with this output voltage V, and when the output voltage V exceeds the reference voltage Vl, it is recognized that the long wavelength optical sensor 42 has contacted the finger 12, AND circuit 46! The level of the terminal becomes “1”.

At the same time, this output voltage V is input to the comparison voltage generation circuit 43, and the comparison voltage Vr, which is determined by the conversion coefficient preset in the comparison voltage generation circuit 43 and the output voltage ■, Vr=-V, is generated by the comparison voltage generation circuit 43. 43.

The output voltage Vo of the short wavelength optical sensor 41 and the comparison voltage Vr are compared by a biometric identification comparator 44.

Here, if the subject is a living body, immediately after the short wavelength optical sensor 41 contacts the finger 12, the relationship is Vo<Vr, but as pressure is applied, the magnitude relationship is reversed and the relationship becomes Vo≧Vr.

The biological identification comparator 44 detects the relationship between the output voltage Vo of the short wavelength optical sensor 41 and the comparison voltage Vr, and outputs an identification signal when the output voltage Vo≧comparison voltage Vr is established, and the S of the AND circuit 46 The terminal level is “1’”
become.

The long wavelength optical sensor 42 contacts the finger 12 and the AND circuit 46
The level of the l terminal becomes “1” and the output voltage Vo≧
When the level of the S terminal of the AND circuit 46 becomes "1" due to the relationship of the comparison voltage Vr, the flip-flop (FF)
47 is set, and the comparison between the fingerprint input from the fingerprint sensor 1 and the fingerprint stored in the information matching dictionary 2 is started. Note that a flip-flop (FF) 47 switches the contact detection comparator 4 when the finger leaves the living body detection optical system.
5 is inverted and reset.

If the subject is something other than a living body, the short wavelength optical sensor 41
The above relationship does not exist between the output voltage Vo and the comparison voltage VrO, and no identification signal is output from the biometric identification comparator 44.

After confirming that the subject is a living body using a living body detection means that utilizes the pressure dependence in which the reflectance changes greatly depending on pressure in the visible light region of 580 nm or less, which is unique to human skin, By comparing the fingerprint input from the fingerprint sensor 1 with the fingerprint stored in advance in the information matching dictionary 2, it is possible to prevent the personal matching system from being misused by a replicated subject such as a replica.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to provide a personal verification system having a function of confirming that a subject is a living body.

[Brief explanation of drawings]

Fig. 1 is a bookmark showing the personal verification device of the present invention; Fig. 3 is a plan view 1 showing an embodiment of the living body detection optical system; Fig. 4 is a circuit diagram showing an embodiment of the living body detection means; Fig. 5 6 is a block diagram showing a conventional personal verification device, FIG. 6 is a principle diagram showing an example of a fingerprint sensor, and FIG. 6(a) is a prism-type fingerprint sensor,
FIG. 6('b) shows a hologram type fingerprint sensor. In the figure, 1 is a fingerprint sensor (personal information input means), 2 is a dictionary for information collation, 3 is information collation means, 4 is living body detection means, 12 is a finger (subject), and 41 is a short wavelength optical sensor (short wavelength side). 42 is a long wavelength optical sensor (long wavelength side light detection means), 43 is a comparison voltage generation circuit (comparison voltage generation means), 44 is a biometric identification comparator (comparison means), 45 is a contact detection comparator , 46 is an AND circuit, 47 is a flip-flop (F F), 411.421 is a light emitting diode, 412.422 is a photodiode, the invention is as follows.
Stem 1 Threshold', Jl-L (nm) Human skin has a light reflection level of 4, small t1 寥2 @ 3rd membrane (hi (shi), the island is narrowed, height f) J lip 1 6th eye

Claims (1)

[Claims] 1) After confirming that the subject is a living body by the living body detection means (4), personal information inputted through the personal information inputting means (1) and a dictionary for information matching in advance; A personal verification method characterized in that personal information stored in (2) is verified by information verification means (3). 2) A means (41) for detecting light in the visible light region on the shorter wavelength side of 440 to 580 nm, and a means (41) for detecting light in the visible light region on the longer wavelength side than 630 nm.
42), and comparison voltage generation means (43) that automatically generates a comparison voltage in response to the output voltage of the long wavelength side photodetection means (42).
A personal verification device comprising: a living body detection means (4) comprising a comparison means (44) for comparing the comparison voltage and the output voltage of the short wavelength side light detection means (41).