JPH02167138A - Fingerprint confirming apparatus and method - Google Patents

Abstract

PURPOSE:To obtain a sharp fingerprint wherein ridgelines and trough lines are clearly separated by applying a volatile substance to the fingerprint part of a fingertip to evaporate moisture such as sweat to dry the fingerprint part and applying a liquid for improving the close adhesion of ridgeline parts to press the coated fingerprint part to a fingerprint input surface. CONSTITUTION:The switch provided to a control part 23 is closed in order to input a fingerprint. Drive shafts 12, 18 are started by the control signal from the control circuit 23 not only to rotate belts 11, 17 but also to open control valves 24, 25 and an ethanol solution 14 is supplied to the belt 11 and a non-volatile liquid 20 is supplied to the belt 17. At first, the part impregnated with the ethanol solution of the belt 11 arrives at a volatile substance coating part 9 and the fingerprint part of a fingertip is pressed to the volatile substance coating part 9 to apply the ethanol solution to the fingerprint part. Then, the ethanol solution is evaporated and dried and, thereafter, the fingerprint part is pressed to a non-volatile liquid coating part 10 to be coated with the non- volatile liquid and, when the fingerprint part is pressed to a fingerprint input surface 1a, the fingerprint is confirmed by a fingerprint sensor.

Description

[Detailed Description of the Invention] [Summary] This invention relates to a fingerprint recognition device and a fingerprint recognition method for registering a fingerprint or comparing it with already registered fingerprints. In order to prevent fingerprints from being recognized in the state of and a non-volatile liquid applying part containing a non-volatile liquid for applying the non-volatile liquid to the ridges of the fingerprint area after moisture is dried by the volatile substance. Use a fingerprint recognition device.

Then, after applying a volatile substance to the fingerprint area in advance and drying the moisture, a non-volatile liquid is applied to the ridges of the fingerprint area, and the fingerprint area is then imprinted on the fingerprint input surface. Recognize.

[Industrial application field]

TECHNICAL FIELD The present invention relates to an apparatus and method for recognizing a fingerprint in order to register the fingerprint or to compare the fingerprint with an already registered fingerprint.

[Conventional technology]

In recent years, as electronic computers have become widespread throughout society, public interest has been focused on how to ensure safety (security). For example, ID cards and PIN numbers have been used to verify identity when entering a computer room or using a terminal, but many questions have been raised from the perspective of ensuring safety. Fingerprints, on the other hand, are considered the most powerful means of identity verification because they have three major characteristics: ``university for all people'' [unchangeable throughout life], and there are many Research and development is underway.

As described above, in a system that performs fingerprint verification as a personal identification method, the fingerprint is usually treated as an image, and an input device for converting the fingerprint into image data is required. A fingerprint is a concavo-convex pattern, and detection and recognition of this concave-convex pattern is performed on the principle shown in FIG. Reference numeral 1 designates a transparent flat plate, and when the fingerprint portion of the fingertip 2 is pressed against the surface of the transparent flat plate 1, the convex portions (ridges) of the fingerprint come into contact, but the concave portions (valley lines) do not. Transparent flat plate 1 by light source 3
When light enters the finger and shines on the flat surface against which the fingerprint is pressed, the light is reflected and scattered on the finger surface and inside. Since the scattered light from the concave portion of the finger passes through the air at -degrees and enters the transparent flat plate 1, there is no component that is totally reflected and propagated through the transparent flat plate 1. However, the reflected/scattered light from the convex portion directly enters the transparent plate 1 from the finger as a spherical wave, and a part of it satisfies the condition for total reflection in the transparent plate 1 and completely passes through the transparent plate 1. The reflection propagates repeatedly. When this total reflection component is imaged by a suitable optical system 4 and detected by an image sensor 5, an image of a convex part (ridge) pattern can be obtained.

[Problem to be solved by the invention]

FIG. 6 is a diagram showing a fingerprint input operation in a conventional fingerprint recognition device, and shows a cross-sectional state of a fingerprint section.

A fingerprint is input by pressing the fingerprint part of the fingertip 2 against the transparent flat plate 1. However, if the fingerprint part is sweaty and moisture 6 has adhered to the recessed part, the moisture 6 may form as shown in Fig. 7. , a bridging portion 7 is generated in the recessed portion. Normally, only the ridge images 8 should be included, but if the ridge images 8 are connected by the bridging portion 7, a different feature than originally intended will be input. Furthermore, there are individual differences in the state of sweating, and even in the case of the same person, the state of sweating differs depending on the state at the time, making it difficult to stably obtain accurate fingerprint images.

A technical problem of the present invention is to prevent a fingerprint image from being erroneously recognized due to moisture such as sweat.

[Means to solve the problem]

FIG. 1 is a diagram illustrating the basic principle of a fingerprint recognition device according to the present invention. 1a is a fingerprint input surface for detecting and inputting a fingerprint with a fingerprint sensor, and 9 is a volatile substance application part containing a volatile substance for applying a volatile substance to the fingerprint area. IO is a non-volatile liquid application part that contains a non-volatile liquid to apply the non-volatile liquid to the ridges of the fingerprint area after moisture is dried by the volatile substance.

In order to perform fingerprint recognition using this device, a volatile substance is applied in advance to the fingerprint portion of the fingertip by the volatile substance application section 9, and moisture is dried. Next, a nonvolatile liquid is applied to the ridges of the dried fingerprint part by the nonvolatile liquid application part IO, and the fingerprint part is pressed onto the fingerprint input surface 1a to perform a manual fingerprint test.

[Effect]

Press the fingerprint part of the fingertip 2 against the volatile substance application part 9,
After applying the volatile substance to the fingerprint area, by removing the fingertip 2 from the volatile substance application area 9, moisture such as sweat on the fingerprint area evaporates and dries.

Therefore, by stamping the dried fingerprint portion, bridging portions that bridge between ridge portions are not generated during fingerprint recognition, and there is no risk of inputting a noisy fingerprint.

Although it is possible to immediately press the dried fingerprint onto the fingerprint input surface 1a, it is also possible to apply the nonvolatile liquid to the ridges of the dried fingerprint in the nonvolatile liquid application section IO. , the ridge part and the fingerprint input surface 1a
This improves the adhesion with the fingerprint input surface 1a, and the ridge portion uniformly and reliably comes into close contact with the fingerprint input surface 1a. As a result, a clear fingerprint image is obtained.

[Example] Next, how the fingerprint recognition device and the fingerprint recognition method according to the present invention are actually implemented will be explained using examples. FIG. 2 is a conceptual diagram showing an embodiment of a fingerprint recognition device. 11
is a belt made of hygroscopic material, such as paper, cloth,
Absorbent cotton is suitable. This belt 11 is connected to the drive shaft 1
2 and the driven shaft 13. And belt 1
On one end of 1 is a container 15 containing an ethanol solution 14.
An outlet 16 is provided. The other end 9 of the belt 11 is a volatile substance application part, and is adapted to apply an ethanol solution by pressing the fingerprint part of the fingertip onto the other end 9 of the belt 11.

Numeral 17 is a belt made of a hygroscopic material like the belt 11, and is wound around a drive shaft 18 and a driven shaft 19. An outlet 22 of a container 21 containing a non-volatile liquid 20 is disposed on one end of the belt 17.

The other end 10 of the bell) 17 is a non-volatile liquid applicator, and is adapted to apply a non-volatile liquid by pressing the fingerprint area of the fingertip.

A control circuit 23 controls the drive shaft 12, the control valve 24 of the outlet 16, the drive shaft 18, and the control valve 25 of the outlet 22, and also includes a fingerprint registration circuit and a verification circuit.

In this device, in order to input a fingerprint, first a switch provided in the control circuit 23 is closed.

Then, in response to a control signal from the control circuit 23, the drive shaft 12.18 is started to rotate the belt 11 and F, and the control valve 24.25 is opened, so that the ethanol solution is supplied to the bell 1-11. A non-volatile liquid is supplied to each belt 17.

Therefore, first, the part of the belt 11 soaked with the ethanol solution reaches the volatile substance application part 9, and then the fingerprint part of the fingertip is pressed against the volatile substance application part 9, and the ethanol solution is applied to the fingerprint part. .

After the ethanol solution has vaporized and dried, the fingerprint section is pressed against the non-volatile liquid application section 10 to apply the non-volatile liquid, and then the fingerprint section is pressed on the fingerprint input surface 1a. Fingerprint recognition is performed.

FIG. 3 is a perspective view showing the appearance of this fingerprint recognition device. The healds 11 and 17 are arranged in parallel, and the volatile substance application section 9 and the nonvolatile liquid application section 10 are arranged on the same surface as the fingerprint input surface 1a.

Therefore, when inputting a fingerprint, it is sufficient to press the fingerprint portion of the fingertip against the volatile substance coating section 9, the nonvolatile liquid coating section 10, and the fingerprint input surface 1a in this order, and the operation is extremely simple.

FIG. 4 is a diagram sequentially showing the state of the surface of the fingerprint section when a fingerprint is input. As shown in (a), moisture 6 such as sweat usually adheres to the fingerprint portion of the fingertip 2 and accumulates in the recess, causing bridging during fingerprint recognition as described above.

In the apparatus of the present invention, when a fingerprint part is pressed against the volatile substance application part 9 to apply a volatile substance, and the volatile substance is vaporized and dried together with moisture, a moisture-free state is obtained as shown in (b). becomes.

Next, when the fingerprint portion is pressed against the non-volatile liquid coating portion IO and a non-volatile liquid is applied, the non-volatile liquid 26 adheres only to the ridges of the fingerprint, as shown in (C).

In this state, if you press the fingerprint part against the fingerprint input surface 1a,
As shown in (d), only the ridge portions are uniformly and reliably brought into close contact with the fingerprint input surface 1a using the non-volatile liquid 26 as a medium.

Therefore, when a fingerprint is detected and recognized by the print recognition means shown in Fig. 5, only the ridges of the fingerprint are accurately recognized, and no bridging parts are present. A fingerprint image is obtained.

Note that as the volatile substance, an ethanol solution with a concentration of about 70% is suitable, but it is not limited thereto. In addition, the liquid for improving the adhesion between the ridges and the fingerprint input surface 1a may be non-volatile, but liquids containing oils and fats, especially animal oils and fats such as butter, may be used. Liquid containing it is suitable.

The fingerprint recognition device and fingerprint recognition method of the present invention can be applied not only to the case of recognizing a fingerprint for comparison with an already registered fingerprint image, but also to the case of inputting a fingerprint for new registration.

〔Effect of the invention〕

As described above, according to the present invention, a volatile substance is applied to the fingerprint area of the fingertip, moisture such as sweat is evaporated and dried, and then,
It is designed to be stamped on the fingerprint input surface. Therefore, problems such as bridging parts caused by sweat or the like between the ridges and errors in fingerprint recognition can be solved. In addition, since a liquid is applied to improve the adhesion of the ridges before being stamped on the fingerprint input surface, only the ridges of the fingerprint are evenly and reliably adhered to the fingerprint input surface, and the ridges and valleys are A clearly separated fingerprint image can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a diagram explaining the basic principle of the fingerprint recognition device and fingerprint recognition method according to the present invention, FIG. 2 is a conceptual diagram showing an embodiment of the fingerprint recognition device, and FIG. 3 is a diagram showing the external appearance of the same embodiment device. , FIG. 4 is a diagram sequentially showing the state of the surface of the fingerprint section when a fingerprint is input. FIG. 5 is a diagram illustrating the principle of fingerprint recognition, FIG. 6 is a diagram illustrating a conventional fingerprint recognition operation, and FIG. 7 is a diagram illustrating a conventional recognized fingerprint image. In the figure, l is a transparent flat plate, 1a is a fingerprint input surface, 2 is a fingertip, 6 is moisture such as sweat, 7 is a bridge part, 8 is a ridge image, 9 is a volatile substance application part, and 10 is a non-volatile liquid Application section, 11 is a belt for applying volatile substances, 14 is an ethanol solution, 1
7 is a belt for applying a non-volatile liquid, 20 is a non-volatile liquid, and 23 is a control circuit. Patent Applicant: Fujitsu Limited, Sub-Agent, Patent Attorney: Yasushi Fukushima, Bunbo Benro ω Kiho Ryo Rika l Senfu n Mi ε Itaj (6 butoshi 141 child Fumi C Yunu 3 dent lσ Dai R, example 9 砥Imakuni No. 22, Ward 4, 3, Koryogo, 1, Monki, Knowledge, ■Principle, 5th prisoner.

Claims (1)

[Claims] 1. A fingerprint input surface (1a) for detecting and inputting a fingerprint using a fingerprint sensor; and a volatile substance coating containing a volatile substance for applying a volatile substance to the fingerprint area. a non-volatile liquid application part (10) containing a non-volatile liquid for applying the non-volatile liquid to the ridges of the fingerprint area after moisture has been dried by the volatile substance; A fingerprint recognition device comprising: 2. After applying a volatile substance to the fingerprint area in advance and drying the moisture, press the fingerprint area onto the fingerprint input surface (1a) while applying a non-volatile liquid to the ridges of the fingerprint area. A fingerprint recognition method characterized by: