JP2003050991A - Fingerprint image reader and fingerprint checking device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fingerprint checking device and a fingerprint image reader which eliminate the need for noise removal from a read fingerprint image through filter processing, are low-cost, and can shorten the processing time. SOLUTION: The light from a lighting part 1 is reflected by a finger mount surface 1A of a prism 1 and converged by a lens 2 on a CCD image pickup element 3. The CCD image pickup element 3 is arranged off the focus position of the lens 2 by shortening the distance between the lens 2 and the CCD image pickup element 3. Consequently, the reflected light impinging on a photodetection surface of the CCD image pickup element becomes out of focus and becomes a state just like high-frequency components of spatial frequency are cut and noise components due to sweat, fine dust, etc., are removed. A noise removing function by an optical path like this, therefore, eliminates the need to provide other noise removing means and high-frequency noise can easily be removed without requiring a new circuit nor program.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fingerprint image reading device and a fingerprint collating device for optically reading a human fingerprint image for various authentications.

[0002]

2. Description of the Related Art Conventionally, in a fingerprint image reading device or a fingerprint collation device, a finger for reading a fingerprint image is placed on a transparent finger rest, and the finger rest is penetrated to expose the surface of the finger. It is known to irradiate a laser beam, and transmit the reflected light through a lens to read it with a detection element such as a CCD. By the way, in such a fingerprint image reading apparatus or fingerprint collation apparatus that optically reads a fingerprint, sweat, fine dust particles, sweat glands, and the like change each time the fingerprint image is read, which causes noise in the fingerprint image. These noises are a factor that deteriorates the collation performance when performing fingerprint collation, and therefore need to be removed. Therefore, as a conventional method for removing such noise, for example, Japanese Patent Laid-Open No. 11-3453
As disclosed in No. 32, "Fingerprint Matching Device", there is a method of removing noise with an image processing filter after reading a fingerprint image.

[0003]

However, in the above-mentioned prior art, a new program is required when processing is performed by new hardware or a microcomputer to remove noise, which causes an additional cost. was there. Further, since the noise removal processing is performed after the image is read, it takes a long time to perform the processing, and as a result, there is a problem that fingerprint registration and verification time becomes long.

Therefore, an object of the present invention is to provide a fingerprint image reading device and a fingerprint collation device which do not require noise removal by filtering a read fingerprint image and can reduce processing time at low cost.

[0005]

In order to achieve the above object, the present invention has a transparent finger rest on which a finger for reading a fingerprint image is placed, and a transparent finger rest on the surface of the finger through the finger rest. Illuminating means for irradiating light, a detection element for detecting a fingerprint image from the light received on the light receiving surface, and reflected light emitted from the illuminating means and reflected by the surface of the finger placed on the finger rest is An image forming means for forming an image on the light receiving surface of the detecting element, and by shifting the image forming position of the reflected light by the image forming means from the light receiving surface of the detecting element, a high frequency component contained in the reflected light is removed. It is characterized by doing so.

According to the present invention, a transparent finger rest on which a finger for reading a fingerprint image is placed, an illuminating means for irradiating the surface of the finger with light through the finger rest, and a light receiving surface. A detection element for detecting a fingerprint image from the received light, and a light transmission means for transmitting the reflected light emitted from the illumination means and reflected on the surface of the finger placed on the finger rest to the light receiving surface of the detection element. And separating the light emitting surface of the light transmitting means and the light receiving surface of the detection element to diffuse a part of the reflected light incident on the light receiving surface, thereby changing the high frequency component contained in the reflected light. The feature is that it is removed.

Further, according to the present invention, in a fingerprint collation device for collating a fingerprint based on a fingerprint image read by the fingerprint image reading unit, the fingerprint image reading unit is a transparent finger mount on which a finger for reading the fingerprint image is placed. The placing part, an illuminating means for irradiating the surface of the finger with light through the finger placing part, a detection element for detecting a fingerprint image from the light received on the light receiving surface, and an illuminating means for emitting light. Image forming means for forming an image on the light-receiving surface of the detection element by the reflected light reflected by the surface of the finger placed on the finger rest, and the image forming position of the reflected light by the image forming means is detected by the detection element. It is characterized in that the high frequency component contained in the reflected light is removed by shifting from the light receiving surface.

Further, the present invention is a fingerprint collation device for collating a fingerprint based on a fingerprint image read by the fingerprint image reading unit, wherein the fingerprint image reading unit is a transparent finger mount on which a finger for reading the fingerprint image is placed. The placing part, an illuminating means for irradiating the surface of the finger with light through the finger placing part, a detection element for detecting a fingerprint image from the light received on the light receiving surface, and an illuminating means for emitting light. A light transmitting means for transmitting the reflected light reflected by the surface of the finger placed on the finger rest to the light receiving surface of the detecting element, and the emitting end surface of the light transmitting means and the light receiving surface of the detecting element are provided. It is characterized in that a high frequency component included in the reflected light is removed by separating a part of the reflected light which is incident on the light receiving surface and diffused.

In the fingerprint image reading apparatus of the present invention, the image forming position of the reflected light by the image forming means is shifted from the light receiving surface of the detection element to remove the high frequency component contained in the reflected light. It is possible to remove noise from the fingerprint image without using a special filter or the like.
Therefore, it is possible to provide a high-performance fingerprint image reading device that can realize high-frequency noise removal without requiring new hardware or software, and can be manufactured at low cost. Further, the processing time can be shortened and high-speed processing can be realized as compared with the case where noise is removed by hardware or software.

Further, in the fingerprint image reading apparatus of the present invention, the emitting end surface of the light transmitting means and the light receiving surface of the detection element are separated from each other to diffuse a part of the reflected light incident on the light receiving surface.
Since the high frequency component contained in the reflected light is removed, it is possible to remove the noise of the fingerprint image only by generating the aberration without using a special filter or the like. Therefore, it is possible to provide a high-performance fingerprint image reading device that can realize high-frequency noise removal without requiring new hardware or software, and can be manufactured at low cost. Also,
The processing time can be shortened and high-speed processing can be realized compared to the case where noise is removed by hardware or software.

Further, in the fingerprint collating apparatus of the present invention, the image forming position of the reflected light by the image forming means is shifted from the light receiving surface of the detection element to remove the high frequency component contained in the reflected light. It is possible to remove noise from the fingerprint image without using a special filter or the like.
Therefore, it is possible to provide a high-performance fingerprint collation device at a low cost that can realize high-frequency noise removal without requiring new hardware or software. Further, the processing time can be shortened and high-speed processing can be realized as compared with the case where noise is removed by hardware or software.

Further, in the fingerprint collating apparatus of the present invention, the emitting end surface of the light transmitting means and the light receiving surface of the detecting element are separated from each other, and a part of the reflected light incident on the light receiving surface is diffused to be included in the reflected light. Since the high-frequency component is removed, it is possible to remove the noise from the fingerprint image only by generating aberration without using a special filter or the like. Therefore, it is possible to provide a high-performance fingerprint collation device at a low cost that can realize high-frequency noise removal without requiring new hardware or software. Further, the processing time can be shortened and high-speed processing can be realized as compared with the case where noise is removed by hardware or software.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a fingerprint image reading device and a fingerprint collating device according to the present invention will be described below. The embodiments described below are preferred specific examples of the present invention, and various technically preferable limitations are given. However, the scope of the present invention is not limited to the present invention in the following description. Unless otherwise stated, the present invention is not limited to these embodiments.

FIG. 1 is a block diagram showing the outline of a fingerprint collation apparatus according to the first embodiment of the present invention, and FIG.
FIG. 2 is a perspective view showing an appearance of the fingerprint matching device shown in FIG. 1. FIG. 3 is a block diagram showing a state in which the image forming position of the read image is shifted in the optical path of the fingerprint collation device shown in FIG. Hereinafter, the configuration of the fingerprint collation device according to the first embodiment of the present invention will be described in detail. As shown in Figure 1,
The fingerprint collation device according to the present embodiment has a prism 1 as a finger placement unit, a lens 2 as an image forming unit, a CCD image pickup device 3 as a detection element, a CCD driving unit 4, and an illumination unit as an illumination unit. It has a unit 5, a CPU 6, an authentication unit 7, and a memory 8.

First, each part will be described with reference to FIGS. The prism 1 is, for example, a glass triangular prism, and is provided with a finger placement surface 1A for placing a finger 9 of a user who reads a fingerprint image on an inclined surface of about 45 degrees.
The finger placement surface 1A is incorporated in the apparatus housing 10 in an exposed state. Light incident on the prism 1 from the illumination unit 5 is reflected by the finger placement surface 1A on which the user's finger 9 is placed by about 90 degrees, and the reflected light is emitted toward the lens 2. The prism 1 is for converting the unevenness of a fingerprint into the intensity of light, and the principle thereof will be described next.

First, when nothing is placed on the finger placement surface 1A of the prism 1, that is, when the entire finger placement surface 1A is in contact with air, 45 of the incident light from the illumination unit 5 is included.
Light incident on the upper surface of the prism at an incident angle of about 10 degrees satisfies the condition of total reflection, so that the light is reflected without being scattered. On the other hand, when the finger is placed on the finger placement surface 1A of the prism 1, the convex portion of the fingerprint touches the prism 1, which means that the sweat or oil of the finger 9 touches the prism 1. , The difference in refractive index with glass is smaller than that with air. Therefore, total reflection hardly occurs and light is scattered, so that the amount of reflected light is reduced in the convex portion of the fingerprint, and as a result, the amount of image formation light in the CCD image pickup device 3 is also reduced. In this way, the unevenness of the fingerprint is converted into light intensity and the pattern is detected by the CCD image pickup device 3.

The lens 2 collects the light reflected by the prism 1 and forms an image on the light receiving surface of the CCD image pickup device 3. In such a lens 2, the image at the point A (the finger placement surface 1A of the prism 1) in FIG.
Ideally, an image is formed on the light receiving surface of the CD image pickup device 3) without distortion or aberration, and the lens shape is designed so as to approach it. In addition, the CCD image pickup device 3 is formed by arranging image pickup pixels by a photodiode that converts the intensity of light into an electric signal in a two-dimensional matrix, and provides a two-dimensional gray gradation image. CC
The D drive unit 4 is for generating a signal necessary for operating the CCD image pickup device 3.

The illumination unit 5 is composed of a plurality of LEDs arranged side by side, for example, and serves as a light source for focusing a fingerprint on the CCD image pickup device 3. The CPU 6 is, for example, a one-chip microcomputer, and controls the entire fingerprint collation device. The authentication unit 7 is, for example, a custom LSI for fingerprint collation, and creates registered fingerprint data or performs fingerprint collation based on the fingerprint image data sent from the CCD image sensor 3 to determine whether or not they are the same. It is a thing. The memory 8 is, for example, a non-volatile flash memory, and stores the registered fingerprint data created by the authentication unit 7.

Next, a noise removing method in the fingerprint collation apparatus of this example will be described with reference to FIG. The state shown in FIG. 1 shows the image formation state of a normal fingerprint collation device. The light flux from point A of prism 1 is condensed by lens 2,
The CCD image pickup element 3 converges to one point B. On the other hand, the optical path shown in FIG.
The only difference is that the distance between and is shortened. As a result, the CCD image pickup device 3 is displaced from the focal position of the lens 2, and the light flux from the point A of the prism 1 does not become a point like the point B in FIG. like,
It will hit the light receiving surface of the CCD image pickup device 3 in a constant spread state. That is, the focus is out of focus. Here, the out-of-focus state is a state in which high-frequency components of the spatial frequency are cut, which is the same as the state in which noise components due to sweat, subtle dust, etc. are removed. Therefore, by the noise removing function by such an optical path, it is not necessary to provide any other noise removing means, and the high frequency noise can be easily removed without the need for a new circuit or program.

Next, a second embodiment of the present invention will be described. FIG. 4 is a side view showing the outline of the fingerprint image reading unit of the fingerprint collation device according to the second embodiment of the present invention, and FIG. 5 is a view showing an optical fiber bundle in the optical path of the fingerprint image reading unit shown in FIG. It is a block diagram which shows the state which separated the photoelectric conversion element. This fingerprint collation device is an example in which the "uneven pattern input device" of Japanese Patent Laid-Open No. 6-300930 is applied to the present invention, and an optical fiber bundle is provided as a light transmission means for transmitting the reflected light from the finger rest. In addition, a plurality of photoelectric conversion elements are used as detection elements.
That is, the fingerprint collation device according to the present embodiment has an illumination unit 11 as an illumination unit, an image input unit 12 as a finger placement unit, an optical fiber bundle 13 as a light transmission unit, and a photoelectric conversion unit as a detection element. And a section 14. It should be noted that a CPU, a memory, an authentication unit, etc. for performing collation and authentication processing are omitted.

First, each part will be described with reference to FIG. The illumination unit 11 is composed of, for example, an LED element and serves as a light source for reading a fingerprint image. The light from the illuminating unit 11 is supplied to each of the optical fibers 13A and 1A of the optical fiber bundle 13.
After entering the optical fibers 3B and 13C, the respective optical fibers 13A and 1C
It is transmitted through the insides of 3B and 13C to the end face on the finger placement unit 12 side, reflected by this end face, and emitted to the photoelectric conversion unit 14.
In addition, in this example, the light from the illumination unit 11 is the optical fiber bundle 1
Since the light enters the optical fiber 3 at an incident angle of 90 degrees, it is possible to supply light into the respective optical fibers 13A, 13B, 13C without reflection. The image input unit 12 is a finger placement unit configured by the cross section of the optical fiber bundle 13, and uses the light of the illumination unit 11 as a light source to display the image of the finger 9 on each of the optical fibers 13A, 13B, and 1.
It is supplied in the state of being divided every 3C. In this example, for the purpose of protecting each of the optical fibers 13A, 13B, and 13C, an integrated plate-shaped image capturing section 12 is provided at the end of the optical fiber bundle 13, but the optical fiber bundle 13 is provided. It does not matter even if the section of is used as it is.

The optical fiber bundle 13 is made of, for example, a large number of plastic optical fibers (three fibers 13A in the figure,
13B and 13C are shown as a representative), and optical fibers thin enough to capture a fingerprint image are bundled. When the finger 9 is placed on the image input unit 12, the light from the illumination unit 11 emits light.
At 2, the light is reflected / scattered by the unevenness of the surface of the finger 9, is transmitted in the fiber, and is supplied to the photoelectric conversion unit 14 without a decrease in the amount of light. That is, the image of the finger 9 on the image input unit 12 can be transmitted to the photoelectric conversion unit 14 through the optical fiber bundle 13 without deterioration.

The photoelectric conversion unit 14 has photoelectric conversion elements 14A, 14B and 14C such as photodiodes arranged in a two-dimensional matrix, and can convert the amount of light incident on the light receiving surface into an amount of current. it can. Each photoelectric conversion element (in the figure, three photoelectric conversion elements 14A, 14B,
14C as a representative) corresponds to each pixel of the fingerprint image. In the configuration shown in FIG. 4, the optical fiber bundle 13 and the photoelectric conversion unit 14 are in close contact with each other, and the amount of light from one optical fiber 13A, 13B, 13C is the photoelectric conversion element 14A facing each, 14B, 14C
The light amount of each pixel is converted into a current amount, and as a result, a fingerprint image can be reproduced.

However, in the present embodiment, as shown in FIG. 5, by arranging the emitting end face of the optical fiber bundle 13 and the light receiving face of the photoelectric conversion portion 14 at a predetermined distance,
Noise of the fingerprint image is removed by diffusing a part of the light incident on each of the photoelectric conversion elements 14A, 14B, and 14C to generate a certain aberration. That is, in the configuration shown in FIG. 4, since the optical fiber bundle 13 and the photoelectric conversion element 14 are in close contact with each other, for example, all the light transmitted through the fiber 13B hits the photoelectric conversion element 14B and is converted into a current, so that an image with high resolution is obtained. However, noise that fluctuates each time an image is captured is accurately transmitted, and the reproducibility of the entire image deteriorates. Therefore, the collation performance is deteriorated.

On the other hand, in the configuration shown in FIG. 5, the light emitting end of the optical fiber bundle 13 and the light receiving surface of the photoelectric conversion unit 14 are not brought into close contact with each other, and a certain distance is maintained, so that the fiber 13B is transmitted. The light is diffused and transmitted while being transmitted through the space between the optical fiber bundle 13 and the photoelectric conversion unit 14, so that not only the photoelectric conversion element 14B but also the photoelectric conversion element 13A and the photoelectric conversion element 14C have the fiber 13B. A part of the light will hit. Similarly, part of the light from the fibers 13A and 13C will hit the photoelectric conversion element 13B. Therefore, with such a configuration, high-frequency noise can be removed, and the influence of noise due to sweat or dust can be reduced.

Next, details of the CCD used in this example will be described. FIG. 6 is an explanatory diagram showing a configuration example of the CCD used in this example, and shows the peripheral configuration of the CCD image pickup device 3 shown in FIG. The CCD 30 accumulates charges in a photosensor 31 arranged two-dimensionally for a certain period of time, and charges the charges in a vertical register 32 and a horizontal register 3.
It is a device that outputs as an analog signal to the outside by transferring using 3. The CCD drive unit 4 generates signals (Vφ1 to Vφ4) for controlling the vertical register 32 and signals (Hφ1 to Hφ2) for controlling the horizontal register 33.

FIGS. 7 and 8 are flowcharts showing the operation of such a CCD 30, FIG. 7 shows the operation of the photosensor 31, and FIG. 8 shows the operation of the registers 32 and 33. Here, the operation of the photo sensor 31 and the operation of each of the registers 32 and 33 are described separately.
This is because the respective operations are independent as parallel processing, but step S2 of FIG. 7 and step S12 of FIG.
Transferring charge from the photosensor 31 to the vertical register 32, showing the same event. Further, while the photo sensor 31 is performing the operation of step S1, the registers 32 and 33 are performing the operation of step S11.

The operation will be described below with reference to FIGS. 7 and 8. In FIG. 7, in step S1, the photo sensor 3
1 accumulates electric charge for a certain time. Then, in step S2, the charges accumulated in the photo sensor 31 are transferred to the vertical register 32. As a result, the charge of the photo sensor 31 disappears. Further, in step S11 in FIG. 8, first, the charges in the leftmost vertical register 32 in FIG. 8 are transferred pixel by pixel to the horizontal register 33, and output from the output terminal Vout to the authentication unit 7 as an analog signal. .
When all the charges in the leftmost vertical register 32 are transferred, the charges in the second vertical register 32 from the left are set to 1
The pixels are similarly transferred to the horizontal register 33 and output from the output terminal Vout.

By performing this for all the vertical registers 32, the charges of the photosensors 31 arranged two-dimensionally are output as a one-dimensional analog signal.
Then, in step S12, electric charge is received from the photo sensor 31. This is the same operation as step S2. The CCD drive unit 4 includes the registers 32 of the CCD 30,
As long as the signal is continuously sent to 33, the above operation is repeated and an analog signal is output from the output terminal Vout.

Next, a specific procedure of the authentication method in this example will be described. Generally, there are various methods such as feature point extraction, direction code matching, and pattern matching in fingerprint collation methods, and the feature point extraction method that is most often used will be described. FIGS. 9A and 9B are explanatory views showing a specific example of a local fingerprint. Figure 9 shows the fingerprint.
The point (end point) where the ridge as shown in FIG.
There are dots (branch points) that branch off as shown in FIG. It is known that these points are called characteristic points, and the arrangement is different from person to person. Therefore, it is possible to determine whether or not the fingerprints are the same by quantitatively evaluating the degree of coincidence of the positional relationship between the characteristic points scattered.

Next, FIG. 10 is a flow chart showing a fingerprint registration operation, and FIG. 11 is a flow chart showing a fingerprint collation operation. First, in the fingerprint registration operation (FIG. 10), the fingerprint image is captured (gray gradation image) in step S101, and the gray gradation image is converted into a binary image in step S102. Then, in step S103, feature points are extracted from the binary image. Next, in step S104, the number of extracted feature points is calculated, and it is determined whether or not there are more than a preset threshold value. Here, if there is a number equal to or larger than the threshold value, the process proceeds to step S105,
If there is not more than the threshold value, the process proceeds to step S101. This is because it is impossible to determine whether or not the fingers are the same unless a certain number or more of feature points are compared,
This is to prevent registration if the number of feature points is less than that number. Next, in step S105, the positional relationship of the extracted feature points is converted into data, and registration data is created. This completes the fingerprint registration operation.

Next, in the fingerprint collation operation (FIG. 11), the fingerprint image is captured (gray gradation image) in step S111, and the gray gradation image is converted into a binary image in step S112. Then, in step S113, feature points are extracted from the binary image. Next, in step S114, the positional relationship of the extracted feature points is converted into data, compared with registered data, and the number of coincidences is calculated. Then, it is determined whether or not the number of coincidences exceeds a preset threshold value, and if it exceeds, it is determined that they are the same fingerprint (step S115). Also,
If the number of matches is less than or equal to a preset threshold, it is determined that the fingerprints are different (step S116). This ends the fingerprint collation operation.

Although the above description has been centered on the fingerprint collation device for collating and authenticating the fingerprint image read from the finger by comparing it with the fingerprint image registered in advance, the present invention has the function of collating and authenticating the fingerprint image. It can also be applied as a separated fingerprint image reading device, and such a fingerprint image reading device is also included in the scope of the present invention.

[0034]

As described above, in the fingerprint image reading device of the present invention, the high-frequency component contained in the reflected light is removed by shifting the image forming position of the reflected light by the image forming means from the light receiving surface of the detection element. By doing so, it is possible to remove noise from the fingerprint image without using a special filter or the like. Therefore, it is possible to provide a high-performance fingerprint image reading device that can realize high-frequency noise removal without requiring new hardware or software, and can be manufactured at low cost. Further, the processing time can be shortened as compared with the case where noise is removed by hardware or software, and a high-speed fingerprint image reading device can be provided.

Further, in the fingerprint image reading apparatus of the present invention, the emitting end surface of the light transmitting means and the light receiving surface of the detecting element are separated from each other to diffuse a part of the reflected light incident on the light receiving surface.
Since the high frequency component contained in the reflected light is removed, it is possible to remove the noise of the fingerprint image only by generating the aberration without using a special filter or the like. Therefore, it is possible to provide a high-performance fingerprint image reading device that can realize high-frequency noise removal without requiring new hardware or software, and can be manufactured at low cost. Also,
A processing time can be shortened as compared with a case where noise is removed by hardware or software, and a high-speed processing fingerprint image reading device can be provided.

In the fingerprint collating apparatus of the present invention, the high-frequency component contained in the reflected light is removed by shifting the image forming position of the reflected light by the image forming means from the light receiving surface of the detection element. It is possible to remove noise from the fingerprint image without using a special filter or the like.
Therefore, it is possible to provide a high-performance fingerprint collation device at a low cost that can realize high-frequency noise removal without requiring new hardware or software. In addition, the processing time can be shortened as compared with the case where noise is removed by hardware or software, and a high-speed fingerprint collation device can be provided.

Further, in the fingerprint collating apparatus of the present invention, the emitting end surface of the light transmitting means and the light receiving surface of the detecting element are separated from each other and a part of the reflected light incident on the light receiving surface is diffused so that the reflected light is included in the reflected light. Since the high-frequency component is removed, it is possible to remove the noise from the fingerprint image only by generating aberration without using a special filter or the like. Therefore, it is possible to provide a high-performance fingerprint collation device at a low cost that can realize high-frequency noise removal without requiring new hardware or software. In addition, the processing time can be shortened as compared with the case where noise is removed by hardware or software, and a high-speed fingerprint collation device can be provided.

[Brief description of drawings]

FIG. 1 is a block diagram showing an outline of a fingerprint matching device according to a first embodiment of the present invention.

FIG. 2 is a perspective view showing an appearance of the fingerprint collation device shown in FIG.

3 is a block diagram showing a state in which an image forming position of a read image is shifted in the optical path of the fingerprint collation device shown in FIG.

FIG. 4 is a side view showing an outline of a fingerprint image reading unit of the fingerprint collation device according to the second embodiment of the present invention.

5 is a block diagram showing a state in which an optical fiber bundle and a photoelectric conversion element are separated from each other in the optical path of the fingerprint image reading unit shown in FIG.

6 is an explanatory diagram showing a configuration example of a CCD used in the fingerprint collation device shown in FIG.

FIG. 7 is a flowchart showing the operation of the CCD photo sensor shown in FIG.

FIG. 8 is a flowchart showing the operation of the CCD register shown in FIG.

FIG. 9 is an explanatory diagram showing a specific example of a local fingerprint.

10 is a flowchart showing a fingerprint registration operation of the fingerprint collation device shown in FIG.

11 is a flowchart showing a fingerprint matching operation of the fingerprint matching device shown in FIG.

[Explanation of symbols]

1 ... Prism, 2 ... Lens, 3 ... CCD image pickup unit,
4 ... CCD drive unit, 5 ... illumination unit, 6 ... CPU, 7
...... Authentication unit, 8 ... Memory, 9 ... Finger, 10 ... Device casing, 11 ... Illumination unit, 12 ... Image input unit, 13 ... Optical fiber bundle, 14 ... Photoelectric conversion unit.

Claims (10)

[Claims] 1. A transparent finger rest on which a finger for reading a fingerprint image is placed, an illuminating means for irradiating the surface of the finger with light through the finger rest, and light received on a light receiving surface. A detection element for detecting a fingerprint image from the detection means, and an image formation means for forming an image on the light receiving surface of the detection element of the reflected light emitted from the illumination means and reflected by the surface of the finger placed on the finger rest. A fingerprint image reading device, characterized in that a high-frequency component included in the reflected light is removed by shifting an image forming position of the reflected light by the image forming means from a light receiving surface of the detection element. . 2. The fingerprint image reading device according to claim 1, wherein the image forming unit is a lens. 3. The fingerprint image reading device according to claim 1, wherein the finger rest is formed of a prism. 4. A transparent finger rest on which a finger for reading a fingerprint image is placed, illumination means for illuminating the surface of the finger with light through the finger rest, and light received on a light receiving surface. A detection element for detecting a fingerprint image from the illuminating means, and a light transmission means for transmitting the reflected light emitted from the illuminating means and reflected by the surface of the finger placed on the finger rest to the light receiving surface of the detection element. Then, the high-frequency component contained in the reflected light is removed by separating the light emitting surface of the light transmitting unit and the light receiving surface of the detection element to diffuse a part of the reflected light incident on the light receiving surface. A fingerprint image reading device characterized by the above. 5. The light transmitting means is an optical fiber bundle,
The fingerprint image reading device according to claim 4, wherein the detection element is a plurality of photoelectric conversion elements provided corresponding to the optical fiber. 6. A fingerprint collation device for collating a fingerprint based on a fingerprint image read by the fingerprint image reading unit, wherein the fingerprint image reading unit includes a transparent finger placement unit for placing a finger for reading the fingerprint image. An illuminating means for irradiating the surface of the finger with light through the finger placing part; a detection element for detecting a fingerprint image from the light received on the light receiving surface; Image forming means for forming an image on the light receiving surface of the detecting element by the reflected light reflected by the surface of the finger placed on the part, and the image forming position of the reflected light by the image forming means is the light receiving surface of the detecting element. A fingerprint collation device characterized in that a high frequency component contained in the reflected light is removed by shifting the fingerprint collation. 7. The fingerprint collation apparatus according to claim 6, wherein the image forming unit is a lens. 8. The fingerprint collation apparatus according to claim 6, wherein the finger rest is formed of a prism. 9. A fingerprint collation device for collating a fingerprint based on a fingerprint image read by the fingerprint image reading unit, wherein the fingerprint image reading unit includes a transparent finger placement unit for placing a finger for reading the fingerprint image. An illuminating means for irradiating the surface of the finger with light through the finger placing part; a detection element for detecting a fingerprint image from the light received on the light receiving surface; A light transmitting means for transmitting the reflected light reflected by the surface of the finger placed on the portion to the light receiving surface of the detecting element, and separating the emitting end surface of the light transmitting means and the light receiving surface of the detecting element. A fingerprint collation device characterized in that a high frequency component contained in the reflected light is removed by diffusing a part of the reflected light incident on the light receiving surface. 10. The optical transmission means is an optical fiber bundle, and the detection element is a plurality of photoelectric conversion elements provided corresponding to the optical fibers.
The fingerprint matching device described.