JP2002298131A - Fingerprint measurement device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress degradation of the measurement accuracy of the fingerprint even from a finger with a dry skin. SOLUTION: A temperature control unit 103 for setting the temperature of a sensor chip 101 to be different from that of the atmosphere is disposed below the sensor chip 101.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a fingerprint measurement device for capturing a fingerprint pattern of a finger for collating the fingerprint of the finger.

[0002]

2. Description of the Related Art In the progress of the information society and the environment of the modern society, interest in security technology is increasing. For example, in the information-oriented society, personal authentication technology for system construction such as electronic cash becomes an important key. In fact, research and development of authentication technologies for preventing theft and unauthorized use of cards are being actively conducted (for example, Yoshimasa Shimizu et al.
Examination about C card, IEICE technical report, Technical report
of IEICE, OFS92-32, p25-30 (1992)).

[0003] There are various authentication methods using fingerprints and voice prints as such authentication methods for preventing unauthorized use. Among them, many fingerprint authentication technologies have been developed. . In fingerprint authentication, a fingerprint measuring device capable of inputting a fingerprint image and a collating device for collating a fingerprint image captured by the fingerprint measuring device with registered feature information are required.

[0004] As shown in FIGS. 2A and 2B, a fingerprint measuring device includes a sensor chip 201 for capturing a fingerprint image,
The configuration is such that it is arranged in the housing 202. The finger 204 is moved to the sensor chip 201 in accordance with the position of the sensor chip 201.
The fingerprint image of the placed finger 204 is placed on the sensor chip 2.
01. The fingerprint image obtained by the measurement in this manner is obtained as shown in FIG. As described above, a fingerprint whose pattern state is clearly obtained as an image can improve the accuracy of fingerprint collation.

[0005]

However, when the user's fingertip is generally called dry skin, there is a problem that the accuracy of fingerprint measurement is reduced. The present invention has been made to solve the above-described problems, and has as its object to suppress a decrease in fingerprint measurement accuracy even with a finger whose skin is dry.

[0006]

According to the present invention, there is provided a fingerprint measuring device which is arranged at an upper portion of a housing and reads a fingerprint pattern as image data, and a temperature which makes the temperature of the fingerprint measuring portion different from the atmosphere. And a control unit. According to the present invention, the finger that has come into contact with the fingerprint measurement unit comes into contact with a portion having a temperature different from that of the atmosphere, thereby promoting a sweating action due to tension.

In the above invention, a storage unit in which the fingerprint pattern data is stored, and a comparison / collation unit for comparing and collating the fingerprint pattern data stored in the storage unit with the image data read by the fingerprint measurement unit. For example, the fingerprint measurement unit, the storage unit, and the comparison and collation unit may include
What is necessary is just to use what was integrated in one sensor chip and the temperature control part arrange | positioned under the sensor chip.
Further, the temperature control unit may be incorporated in the sensor chip.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram illustrating a configuration of a fingerprint measurement device according to an embodiment of the present invention. In the present fingerprint measurement device, a sensor chip 101 is disposed on an upper surface of a housing 102, and a sensor chip 10 is disposed below the sensor chip 101.
Temperature control unit 1 that makes temperature of 1 different from atmosphere
03 is arranged. As shown in FIG. 1B, the sensor chip 101 includes a fingerprint measurement unit 111, a fingerprint image processing unit 112, a storage unit 113, a fingerprint collation unit 114, and a control unit 115. That is, the fingerprint measurement device in FIG. 1 is a fingerprint collation device.

The operation of fingerprint recognition by this fingerprint collating apparatus will be described. First, the temperature controller 103 raises the temperature of the sensor chip 101 to, for example, room temperature higher than 20 ° C.
Control so as to be 0 ° C. In this state, when the finger 104 of the recognition target is placed on the fingerprint measurement unit 111 of the sensor chip 101, the control unit 115 causes the fingerprint image of the finger placed on the fingerprint measurement unit 111 to be read. Fingerprint measurement unit 11
When 1 reads a fingerprint image, the control unit 115 causes the fingerprint image processing unit 112 to perform predetermined image processing on the read fingerprint image. Lastly, the control unit 115 causes the fingerprint matching unit 114 to compare the fingerprint image subjected to the image processing with the fingerprint image of the recognition target stored in the storage unit 113, and performs fingerprint matching.

In such a fingerprint collation device, the collation result obtained greatly differs depending on the state of the fingerprint image read by the sensor chip 101. For example, if the fingerprint pattern cannot be clearly read by the fingerprint measurement unit 111, the fingerprint cannot be collated. In the case where the user's fingertip is generally called dry skin, the reason why the measurement accuracy of the fingerprint is reduced may be that the fingerprint pattern cannot be read clearly within an acceptable range.

Here, when a moisturizer or the like is applied to the user's finger called dry skin and then fingerprint matching is performed by the above fingerprint matching device, the fingerprint is more accurate than when no moisturizer is applied. It has been found that accurate matching can be obtained. On the other hand, as described above, when the temperature of the sensor chip 101 is set to a temperature different from the temperature of the atmosphere, the fingertip touching the sensor chip 101 secretes sweat and sebum components from the fingerprint ridge line and the sweat pore existing along the top. Become like When a fingertip or the like touches an object at a temperature different from that of the surroundings, the temperature is different from the expected temperature, and the person becomes nervous, and as a result, more sweat is secreted than usual.

As a result, the fingertip touching the sensor chip 101 is in the same state as when the moisturizer is applied, and the sensor chip 101 can perform more accurate collation. The results of experiments on the success rate of personal authentication in fingerprint collation performed on a person with dry skin using the fingerprint collation apparatus of FIG. 1 will be described below. First, the sensor chip 10
In the fingerprint collation performed in a state where 1 was different from the temperature of the atmosphere and sweat was more secreted to the fingertip, the success rate of the personal authentication was 85%. On the other hand, in the fingerprint collation performed without temperature change as before, the success rate of personal authentication
It was very low at 11%.

In the above description, the temperature of the sensor chip 101 is set higher than the temperature of the atmosphere by the temperature control unit 103. However, the temperature is not limited to this, and may be set lower than the temperature of the atmosphere. In the present embodiment, the average temperature of the atmosphere in which the fingerprint measurement device is placed is measured in advance, and the temperature control unit 103 controls the sensor chip 10
1 is a state where the temperature is higher or lower than the measured temperature. Naturally, this temperature control range is set so that the fingertip does not suffer from burns or frostbite. Further, in the above description, the temperature control unit is arranged below the sensor chip. However, the temperature control unit is not limited to this, and may be arranged around the sensor chip, or may be incorporated in the sensor chip. good. In the present invention, the temperature of the fingerprint measurement unit to which the finger directly contacts may be different from the atmosphere.

[0014]

As described above, according to the present invention,
Since the dry fingertip is in a wet state, an excellent effect that a decrease in fingerprint measurement accuracy can be suppressed can be obtained.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a configuration of a fingerprint measurement device according to an embodiment of the present invention.

FIG. 2 is a plan view and a cross-sectional view illustrating a configuration of a conventional fingerprint measurement device.

FIG. 3 is an explanatory diagram showing a state of a fingerprint image obtained by a fingerprint measurement device.

[Explanation of symbols]

101: sensor chip, 102: housing, 103: temperature control unit, 104: finger, 111: fingerprint measurement unit, 112: fingerprint image processing unit, 113: storage unit, 114: fingerprint collation unit.

Continuing on the front page (72) Inventor Hiroki Shuto 2-3-1 Otemachi, Chiyoda-ku, Tokyo Nippon Telegraph and Telephone Corporation (72) Inventor Kenichi Saito 2-3-1 Otemachi, Chiyoda-ku, Tokyo Date Within the Telegraph and Telephone Co., Ltd. (72) Inventor Nobunori Konaka 2-3-1 Otemachi, Chiyoda-ku, Tokyo Nippon Telegraph and Telephone Co., Ltd. F-term (reference) 4C038 FF01 FF05 FG00 5B047 AA25

Claims (4)

[Claims] 1. A fingerprint measuring unit disposed on an upper part of a housing and reading a fingerprint pattern as image data, and a temperature control unit for setting the temperature of the fingerprint measuring unit to a temperature different from the atmosphere. Fingerprint measurement device. 2. The fingerprint measurement device according to claim 1, wherein a storage unit storing fingerprint pattern data, a fingerprint pattern data stored in the storage unit, and image data read by the fingerprint measurement unit. And a comparison and collation unit for comparing and collating with the fingerprint measurement device. 3. The fingerprint measurement device according to claim 2, wherein the fingerprint measurement unit, the storage unit, and the comparison and collation unit are integrated on one sensor chip, and the temperature control unit is disposed below the sensor chip. A fingerprint measurement device characterized by being performed. 4. The fingerprint measuring device according to claim 2, wherein
The fingerprint measurement device, wherein the fingerprint measurement unit, the storage unit, and the comparison and collation unit are integrated on one sensor chip, and the temperature control unit is incorporated in the sensor chip.