JP2008017973A - Individual authentication device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an individual authentication device for which authentication accuracy is secured and handleability is excellent. <P>SOLUTION: A finger placing base for placing the finger of an authentication object is configured such that it is provided with a first surface for abutting the bulb side part more on the distal end side than the first joint of the finger and a second surface for facing the bulb side part more on the root side than the first joint and the first surface is inclined in the direction of bending the first joint of the finger of the authentication object or the like and is disposed at a position lowered in the direction relative to the second surface. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a personal authentication device that performs personal authentication using human biometric information, and more particularly to a technique for performing personal authentication using finger vein imaging information.

  A technique for performing personal authentication using human biometric information has been put into practical use. Among biometric information, development of technology using finger vein information is also progressing in various fields. An authentication technique using finger vein information irradiates light from a light source onto a finger of an authentication target person placed on a finger rest, and images a finger vein formed by the irradiation with a camera. The finger vein image data is compared with registered data registered in advance, and the person to be authenticated is authenticated by identifying the difference between the two data. In this technology, infrared light is irradiated from the back or side of the finger toward the inside of the finger, scattered inside the finger and applied to the finger vein, and the scattered infrared light is absorbed by hemoglobin in the blood of the finger vein Thus, the finger vein image is formed as a dark shadow pattern image. The camera captures the image to obtain a captured image.

  Prior arts related to the present invention and described in patent documents include, for example, Japanese Patent Application Laid-Open No. 2005-128936 (Patent Document 1) and Japanese Patent Application Laid-Open No. 2005-71118 (Patent Document 2). There is something that was done. In Japanese Patent Laid-Open No. 2005-128936, the position of a finger is naturally guided to a specific position, and it is possible to perform stable collation that does not require alignment and rotation correction with respect to a photographed image. In order to provide a finger authentication device capable of improving the accuracy of authentication by eliminating a blood vessel pattern and a finger placement guide for the finger, a finger placement guide for setting the finger position and a light source unit for irradiating the finger with transmitted light An authentication target finger placement guide in which the finger to be authenticated is set. And a non-authentication target finger placement guide section on which a non-authentication target finger is set, and the authentication target finger placement guide section is open at a portion corresponding to the optical opening and has a base portion of the authentication target finger. The part that hits is a concave shape It describes a structure in which to have. Japanese Patent Application Laid-Open No. 2005-71118 discloses imaging for capturing a finger vein image in a personal authentication apparatus that uses an image for a finger vein in order to prevent a decrease in authentication rate due to erroneous insertion of a finger or insertion of a fake finger. A light source that emits light transmitted through the finger, an image calculation unit that performs image matching, a guide unit that indicates an imaging position of the finger, and a detection unit that detects contact of the finger with the guide unit, As the detection unit, a configuration is described in which a switch unit that is pressed down by contact, or an electrical, capacitance, or pressure contact sensor is used.

JP 2005-128936 A JP 2005-71118 A

  In any of the above prior arts, the finger placement surface of the finger placement guide portion (finger placement base) is a surface on which the abdomen portion on the distal end side of the first joint of the finger to be authenticated abuts and the root of the first joint. It is the structure formed in the smooth curved surface shape where the surface which opposes the ventral | abdominal part of the side was continuous. In such a configuration, the bending degree of the finger placed on the finger placement surface varies depending on individual differences in finger length. For example, in the case of a long finger, even if a natural bending degree is obtained, it is short. In the case of a finger, the finger is stretched along the finger placement surface, so that the natural bending degree of the finger cannot be obtained, and the finger blood vessel tends to be compressed. Further, as shown in FIG. 7, when the portion corresponding to the optical opening of the continuous curved finger placement surface of the finger placement base 12 ′ is covered with a light transmissive member or the like, the authentication target finger 3 Even in a natural bent state, the ventral portion thereof is easy to contact the surface of the light transmissive member. When the ventral portion of the finger comes into contact, the finger surface is compressed, making it difficult to obtain a clear image of blood vessels (finger veins). In the case of a short finger, since the ventral portion of the finger comes into contact with the surface of the light-transmitting member or the like with a stronger pressing force than in the case of a long finger, the surface of the finger is strongly pressed, making it clearer. It is difficult to obtain a clear blood vessel (finger vein) image, and the image taken by the camera 13 is also unclear.

  FIG. 8 shows a case where the finger placement surface of the finger placement table 12 ′ is flat with respect to the finger length direction. In this case, the finger 3 extends in a straight line, and the surface 121 ′ of the finger placement surface facing the ventral portion on the distal end side of the finger relative to the first joint of the finger and the first joint The respective ventral portions of the finger 3 are in contact with both surfaces 122 ′ facing the ventral portion on the root side. In this case, since the finger 3 is in a linearly stretched state, the skin of the ventral portion of the finger 3 is pulled in the fingertip direction, and the muscle contracts inside the finger 3 to deteriorate blood flow. Therefore, it becomes difficult to obtain a clear blood vessel image, and an image taken by the camera 13 is also unclear. Further, in this case, since the abdominal side of the finger is likely to come into contact with the finger placement surface being strongly pressed, the surface of the finger is likely to be pressed. The image captured by the camera 13 tends to be unclear. If the captured image becomes unclear, the authentication accuracy decreases.

  FIG. 9 shows a surface 122c of the finger placement surface of the finger placement table 12 ′ that faces the ventral portion of the finger 3 that is closer to the base than the first joint of the finger 3 and faces the portion of the finger 3 that performs angiography. The height position of 'in the Z-axis direction is set to another surface, that is, a surface 121 ′ facing the abdominal side of the tip of the finger 3 relative to the first joint of the finger, a surface 122 d ′ facing the root side of the finger 3, etc. This is a case where the abdominal part of the root side of the first joint is not in contact with the surface 122c ′ at the time of photographing by the camera 13 by lowering the height of the first joint. In this case, although the finger 3 does not contact the finger placement surface (surface 122c ′), the finger 3 is likely to be warped in the Z-axis direction. Is pulled in the fingertip direction, and the muscle contracts inside the finger 3 to deteriorate the blood flow, making it difficult to obtain a clear blood vessel (finger vein) image, and the image taken by the camera 13 tends to be unclear.

FIG. 10 is a diagram for explaining that the image of the blood vessel (finger vein) changes when the finger 3 rotates around the Y axis of the finger rest 12 ′. (A) is a case where the finger 3 does not rotate on the Y axis of the finger rest 12 ′, and (b) is a case where the finger 3 is rotated by an angle α around the Y axis of the finger rest 12 ′. In each figure, (a) shows a cross-sectional model of the finger 3 and (b) shows an image model of a blood vessel (finger vein) of the finger 3. The case of (a), profile 14a is next to the width w of the finger 3, an image 14b of the vessel (finger veins) has a width _{w 1,} the case of (b), the outline 14a of the finger 3 ', (a ), The width w ′ is narrower than the width w of the contour 14a in the case of (), and the blood vessel (finger vein) image 14b ′ is also narrower than the width w ₁ of the image 14b in the case (a). w ₁ '. In the case of (a), the camera captures an image 14b having a width w ₁ as a captured image, and in the case of (b), the image 14b ′ having a narrow width w ₁ ′ is captured as a captured image. . For example, in the case where data of a photographed image of the image 14b of (a) is registered in advance for personal authentication, the data of the photographed image of the image 14b ′ of (b) is registered in the verification at the time of authentication. When compared with the data, the data by the image 14b 'in (b) is judged to be out of the same allowable range as the registered data, that is, the registered data is different. Is likely to be judged. That is, in this case, since the finger 3 is rotated around the Y axis of the finger rest 12 ', the authentication accuracy is reduced, and the person to be authenticated is not authenticated, and is different from the individual corresponding to the registration data. There will be some inconvenience.

In view of the above-described prior art, the problem of the present invention is that in the personal authentication device, the finger placement table is configured such that the finger placed on the finger placement surface is in a state where the finger blood vessel is compressed or the finger is warped. The finger is naturally bent without being in a state, the finger surface is not compressed, the muscles in the finger are not contracted, blood flow is not deteriorated, a clear image is obtained, and authentication accuracy is improved. It is to be able to suppress the decline.
An object of the present invention is to provide an easy-to-use personal authentication apparatus that solves such problems and ensures authentication accuracy.

  In order to solve the above-described problems, in the present invention, in a personal authentication device that performs personal authentication based on an image of a finger vein, a finger rest on which a finger to be authenticated is placed from the first joint of the finger to be authenticated. Also has a first surface for contacting the abdominal portion on the distal end side and a second surface for facing the abdominal portion closer to the root side than the first joint, and the first surface is A configuration is adopted in which the first joint of the finger to be authenticated is tilted in a bending direction with respect to the second surface, such as being lowered in the direction.

  According to the present invention, a clear finger vein image and a clear captured image can be obtained in the personal authentication device, and the authentication accuracy can be improved.

Embodiments of the present invention will be described below with reference to the drawings.
1 to 3 are explanatory views of a first embodiment of the present invention. FIG. 1 is a diagram illustrating a configuration example of a personal authentication device as a first embodiment of the present invention, FIG. 2 is a perspective view illustrating a configuration example of a finger rest used in the personal authentication device of FIG. 1, and FIG. It is a side view of a finger rest. In the first embodiment, a personal computer (hereinafter referred to as a personal computer) and a monitor are used as components of a personal authentication apparatus.

  In FIG. 1, 100 is a personal authentication device, 1 is a photographing unit for photographing a blood vessel (venous vein) of a finger of an authentication subject for personal authentication, 2 is a personal computer and a monitor (referred to as a personal computer / monitor), 11 Is a light source for emitting infrared light or near-infrared light in the imaging unit 1, and 12 is a blood vessel (hereinafter referred to as an authentication target finger or simply a finger) 3 of a person to be authenticated in the imaging unit 1. A finger rest 13 for placing the authentication target finger 3 for imaging (venous veins) 13 captures an image of the finger vein of the authentication target finger 3 formed by infrared light or near infrared light from the light source 11. The camera 21 is in the personal computer / monitor 2 and converts the finger vein image of the authentication target finger 3 captured by the camera 13 of the photographing unit 1 into identification data, and then stores the identification data in advance. Registered data and information The collation unit 22 for identifying the difference between the registered data, that is, determining the difference between the two data, the finger vein image of the authentication target finger 3 photographed by the camera 3 or the finger vein of the authentication target finger 3 separately prepared The recording unit 23 in the personal computer / monitor that stores the image of the image as reference registration data for personal authentication, means for displaying the collation result by the collation unit 21 in the personal computer / monitor 2 as an image or by voice or the like. Reference numeral 24 denotes a power source in the personal computer / monitor 2 that supplies power to the personal authentication device. The power source 24 supplies operating power to the photographing unit 1 in a state where the photographing unit 1 is connected to the personal computer / monitor 2. The recording unit 22 stores digital data registration data.

  The collation unit 21 converts the finger vein image of the authentication target finger 3 taken by the camera 13 into identification data as digital data. The collation unit 21 includes a comparison unit (not shown) and a discrimination unit (not shown), and collates the identification data with the registered data (digital data) to identify the difference between the two data. The comparison unit compares the two data to detect a difference between the two data, and the determination unit determines whether the difference between the two data exceeds a preset allowable range. The difference between the two data is judged. That is, if the difference between the two data exceeds the allowable range as a result of the determination, it is determined that the two data are different from each other, that is, the identification data does not match the registered data. The collation unit 21 sends an output signal “authentication impossible” to the display / notification unit 23. The display / notification unit 23 receives this and displays an image indicating “authentication is not possible” on the monitor screen or performs notification to that effect by voice or the like. On the other hand, if the difference between the two data is within the allowable range as a result of the determination, it is determined that the two data are the same as each other, that is, the identification data matches the registered data. The collation unit 21 sends an output signal of “authentication possible” to the display / notification unit 23. The display / notification unit 23 receives this, displays an image indicating “authentication is possible” on the monitor screen, or notifies the fact by voice or the like.

  The finger rest 12 is opposed to the first surface 121 for contacting the abdomen portion on the distal end side of the first joint of the finger 3 to be authenticated and the abdomen portion on the root side of the first joint. The second surface 122, the first surface 121 is inclined with respect to the second surface 122 in a direction in which the first joint of the authentication target finger 3 is bent, and the second surface 122 An opening 123 is provided in 122. The opening 123 is for passing infrared light or near infrared light that has passed through the authentication target finger 3 and formed an image of a finger vein to the camera 13 side. In the configuration of FIG. 1, the camera 13 is placed at a position facing the opening 123. A filter member that allows infrared light or near infrared light to pass therethrough and blocks other light may be provided in the opening 123. In addition, the camera 13 is not provided at a position facing the opening 123, and reflects the infrared light or near infrared light that has passed through the opening 123 with a mirror or the like to change the optical path and receive the light. It may be provided.

2 and 3 are diagrams showing a configuration example of the finger rest 12 used in the personal authentication device of FIG. 1, FIG. 2 is a perspective view, and FIG. 3 is a side view.
In FIG. 2, the finger rest 12 is provided on the first surface 121 for contacting the abdominal portion on the distal end side with respect to the first joint of the finger 3 to be authenticated and on the abdominal side portion on the root side with respect to the first joint. Both the second surface 122 and the second surface 122 are opposed to each other in a plane shape, and an opening 123 is provided at the center of the second surface 122 and penetrates in the Z-axis direction. The first surface 121 is inclined with respect to the second surface 122 in a direction in which the first joint of the authentication target finger 3 bends. In the figure, point A is the tip position of the first surface 121 and is substantially the center position in the X-axis direction, and point B is the intersection position between the first surface 121 and the second surface 122 and X A substantially central position in the axial direction, point C, is an end position of the second surface 122 and indicates a substantially central position in the X-axis direction. The dimensions of the first surface 121 are, for example, about 20 × 10 ⁻³ m so that the distance between the point A and the point B has a value of 5 to 30 × 10 ⁻³ m. The dimension of the surface 122 is, for example, about 40 × 10 ⁻³ m so that the distance between the point B and the point C has a value of 20 to 50 × 10 ⁻³ m.

  The authentication target finger 3 moves in the direction of arrow E and is placed on the finger rest 12 along a line passing through points A, B, and C. In the placed state, the authentication target finger 3 is in a state in which the first joint is naturally bent corresponding to the inclined state of the first surface 121 and the second surface 122, and moreover, from the first joint, The distal side of the ventral portion is in contact with the first surface 121 along a line connecting the points A and B, and the ventral portion closer to the root side than the first joint connects the points B and C. It is placed on the second surface along the line. In this state, the portion where the blood vessel (finger vein) is imaged is located above the opening 123 in the abdominal portion closer to the root than the first joint of the finger 3 to be authenticated.

  Since the authentication target finger 3 is in a state in which the first joint is naturally bent as described above, the muscle contracts in the finger 3 at the base side of the first joint, resulting in poor blood flow. The surface of the finger 3 is not pressed. In particular, since a portion where a blood vessel (finger vein) is photographed is placed on the upper portion of the opening 123, the finger surface is not brought into contact with the finger rest 12 and the finger surface is released. For this reason, when infrared light or near infrared light from the light source 11 is transmitted through a portion where a blood vessel (finger vein) is photographed, a clear blood vessel (finger vein) image is formed. A clear image can be formed by photographing. Further, since the authentication target finger 3 can contact the finger rest 12 with a width in the X-axis direction at the B point position and the C point position, the authentication target finger 3 can be positioned in the Y axis direction. In addition, rotation around the Y-axis direction can be easily suppressed.

  In FIG. 3, θ is an inclination angle of the first surface 121 with respect to the second surface 122. The inclination angle θ is an angle at which the first joint of the authentication target finger 3 is naturally bent. For example, when the angle θ is in the range of 10 to 45 °, the amount of lifting of the second joint in the Z-axis direction can be reduced, and fluctuations in the position of the authentication target finger 3 in the Z-axis direction can be suppressed. .

  According to the personal authentication apparatus of the first embodiment of the present invention described with reference to FIGS. 1 to 3, a clear finger vein image of the authentication target finger 3 and a clear captured image thereof can be obtained, and the authentication accuracy can be improved. This makes it possible to easily perform accurate personal authentication. The finger rest 12 has a simple configuration, and a photographing unit including the finger rest can be configured at a relatively low cost, and an increase in apparatus cost can be suppressed.

FIG. 4 is an explanatory diagram of a finger rest used in the personal authentication apparatus as the second embodiment of the present invention. The personal authentication apparatus according to the second embodiment is the same as the personal authentication apparatus according to the first embodiment except for the configuration of the parts other than the finger rest.
In FIG. 4, the finger rest 12 has substantially the same configuration as the finger rest shown in FIGS. 2 and 3. That is, since the first flat surface 121 for contacting the abdominal portion on the distal end side of the first joint of the finger 3 to be authenticated and the abdominal portion on the root side of the first joint are opposed to each other. The first surface 121 is inclined with respect to the second surface 122 in a direction in which the first joint of the authentication target finger 3 bends, and It is assumed that an opening 123 is provided in the second surface 122. The inclination angle of the first surface 121 with respect to the second surface 122 is an angle at which the first joint of the authentication target finger 3 is naturally bent as in the case of the first embodiment. For example, when the inclination angle is in the range of 10 to 45 °, the amount of lifting of the second joint of the authentication target finger 3 in the Z-axis direction can be reduced, and the authentication target finger 3 can be lifted in the Z-axis direction. Position fluctuations can also be suppressed. The finger rest 12 shown in FIG. 4 is different from the finger rest shown in FIG. 2 and FIG. 3 in the finger position determining means in the first surface 121 and at the end of the second surface 122, respectively. The only difference is that

In FIG. 4, reference numeral 125 denotes a protrusion as a finger position determining means provided in the surface of the first surface 121, and 126 denotes a protrusion as a finger position determining means provided at the end of the second surface 122. Part. The protrusion 125 determines a position of the finger 3 with respect to the first surface 121 of the finger rest 12 by a part of the tip of the authentication target finger 3 being in contact with the first joint of the finger 3 to be authenticated. Confirms the position of the finger 3 with respect to the second surface 122 of the finger rest 12 by contacting a part of the finger 3 on the base side with respect to the first joint, and more than the first joint. The base side portion is prevented from floating from the finger rest 12. That is, the person to be authenticated senses that the above-described portions of his / her authentication target finger 3 have come into contact with the protrusions 125 and 126, respectively, and stops the finger 3 at this position. Each protrusion portion 125 and 126 is assumed to have the external dimensions of the diameter of 0.2 to 10 × ^{10 -3} m, the height 0.2 to 10 × ^{10 -3} m, for example, a diameter of about 1.0 × 10 ^-3 m and a height of about 1.0 × 10 ⁻³ m. With this configuration, the finger placement table 12 of the authentication target finger 3 can be easily positioned in the Y-axis direction. The dimensions of the first surface 121 and the second surface 122 are the same as those in the first embodiment, and the dimensions of the first surface 121 are, for example, point A and point B. For example, about 20 × 10 ⁻³ m so that the distance between them is 5 to 30 × 10 ⁻³ m, and the dimension of the second surface 122 is, for example, between the point B and the point C The distance is set to a value of 20 to 50 × 10 ⁻³ m, for example, about 40 × 10 ⁻³ m.

As the finger position determining means, a protruding sensor or switch may be provided in place of the protruding portions 125 and 126. In the case where the protrusion-shaped sensor or switch is used, for example, when the corresponding part of the finger 3 to be authenticated touches the protrusion-shaped sensor or switch, the light emission operation by the light source 11 or the photographing by the camera 13 is performed in the apparatus. A signal for starting the operation of the apparatus such as an operation is output, and conversely, when the corresponding part of the authentication target finger 3 is not in contact with the protruding sensor or switch, the apparatus operation is not started. To.
As in the case of the first embodiment, a filter member that allows infrared light or near infrared light to pass through and blocks other light may be provided in the opening 123.

  According to the personal authentication apparatus of the second embodiment of the present invention, as in the case of the personal authentication apparatus of the first embodiment, a clear finger vein image of the authentication target finger 3 and a clear photographed image thereof are obtained. As a result, the accuracy of authentication can be improved, and accurate personal authentication can be easily performed. Since the finger rest 12 has a simple configuration, an increase in cost including the photographing unit can be suppressed. In particular, since the protrusions 125 and 126 or the protrusion-shaped sensors or switches are provided, the authentication target finger 3 can be easily and quickly positioned with respect to the finger rest 12.

FIG. 5 is an explanatory diagram of a finger rest used in the personal authentication apparatus as the third embodiment of the present invention. The personal authentication apparatus of the third embodiment is also assumed to have the same configuration as the personal authentication apparatus of the first embodiment except for the finger rest.
As shown in FIG. 5, in the personal authentication device of the third embodiment, the finger rest 12 is a concave curved surface for contacting the ventral portion on the distal end side with respect to the first joint of the finger 3 to be authenticated. First surface 121a and a concave curved second surface 122 (surfaces 122a ₁ , 122a ₂ and the surface of the opening 123 for facing the ventral part closer to the root side than the first joint). The first surface 121a is inclined with respect to the second surface 122 in a direction in which the first joint of the authentication target finger 3 bends. The first face 121a curved in the X-axis direction, a straight planar provided between the surface 121b ₁ and the surface 121b _2, the second surface 122 curved (surface 122a _1, 122a ₂ and opening including the surface of the parts 123) are the X-axis direction, it is provided between the surface 122b ₁ and the surface 122b ₂ of the straight planar. The opening 123 in the second surface 122, in the Y-axis direction, is provided between the surface 122a ₁ and the surface 122a _2. The plane-plane surfaces 121b ₁ and 121b ₂ are also inclined with respect to the plane-plane surfaces 122b ₁ and 122b ₂ , respectively. In the figure, point A is the position of the tip of the curved first surface 121a and is substantially in the center of the X-axis direction, and point B is the curved first surface 121a and the curved second surface. 122a ₁ is the position of the intersection with the X-axis direction and approximately C, and the point C is the end position of the curved second surface 122a _{2 and} the position of the approximate center in the X-axis direction. The dimensions of the first surface and the second surface are the same as in the case of the first embodiment, and the first surface dimension is, for example, the distance between point A and point B. For example, the distance between the point B and the point C is 20 to 50 ×, for example, about 20 × 10 ⁻³ m so that the value is 5 to 30 × 10 ⁻³ m. 10 as a value of ^-3 m and in example, about 40 × ^{10 -3} m.

In FIG. 5, the authentication target finger 3 moves in the direction of the arrow E to move the point A inside the curved first surface 121 a and the curved second surfaces 122 a ₁ and 122 a ₂ of the finger rest 12. It is placed along a line passing through points B and C. In the placed state, the authentication target finger 3 is in a state where the first joint is naturally bent corresponding to the inclined state between the _first surface 121a and the second surface 122a1, The ventral part on the tip side of the first joint is in contact with the first surface 121a along the line connecting the points A and B, and the ventral part on the base side of the first joint is It is placed on the second surface along the line connecting the points C. In this state, the portion where the blood vessel (finger vein) is imaged is located above the opening 123 in the abdominal portion closer to the root than the first joint of the finger 3 to be authenticated. Since the authentication target finger 3 is in a state where the first joint is naturally bent as described above, the muscle contracts in the finger 3 at the root side of the first joint, resulting in poor blood flow. Also, the surface of the finger 3 is not pressed. In particular, since a portion where a blood vessel (finger vein) is photographed is placed on the upper portion of the opening 123, the finger surface is not brought into contact with the finger rest 12 and the finger surface is released. For this reason, when infrared light or near infrared light from the light source 11 is transmitted through a portion where a blood vessel (finger vein) is photographed, a clear blood vessel (finger vein) image is formed. A clear image can be formed by photographing. Further, since the authentication target finger 3 can come into contact with the finger rest 12 with a width in the X-axis direction at, for example, the B point position and the C point position, the authentication target finger 3 can be positioned together with the Y-axis direction positioning. Positioning in the axial direction is also possible, and rotation around the Y-axis direction can be easily suppressed.

In FIG. 5, the curved first surface 121a, the inclination angle with respect to the second surface 122a ₁ curved is an angle in a state where the first joint of the authentication object finger 3 is bent naturally. For example, when the angle is in the range of 10 to 45 °, the amount of lift of the second joint in the Z-axis direction can be reduced, and fluctuations in the position of the authentication target finger 3 in the Z-axis direction can be suppressed. . The curvature radius of the curved first surface 121a and the curved second surface 122 (including the surfaces 122a ₁ and 122a ₂ and the surface of the opening 123) is, for example, 7 to 15 × 10 ⁻³ m. Scope.
As in the case of the first embodiment, a filter member that allows infrared light or near infrared light to pass through and blocks other light may be provided in the opening 123.

  Also by the personal authentication device of the third embodiment of the present invention using the finger rest 12 of FIG. 5 in the photographing unit, a clear finger vein image of the authentication target finger 3 and a clear photographed image thereof are obtained. Authentication accuracy can be improved, and accurate personal authentication can be easily performed. The finger rest 12 has a simple configuration, and a photographing unit including the finger rest can be configured at a relatively low cost, and an increase in apparatus cost can be suppressed. In particular, in the finger rest 12 of FIG. 5, the authentication target finger 3 is placed inside the curved first surface 121 a and the curved second surface 122. 12 can be easily positioned in the X-axis direction.

FIG. 6 is an explanatory diagram of a finger rest used in the personal authentication apparatus as the fourth embodiment of the present invention. The configuration of the other parts of the personal authentication apparatus of the fourth embodiment except for the finger rest is the same as that of the personal authentication apparatus of the first embodiment.
In the personal authentication apparatus according to the fourth embodiment, the finger rest 12 is a straight plane for contacting the ventral portion on the distal end side of the first joint of the finger 3 to be authenticated, as shown in FIG. The first surface 121 and the second surface 122 (the surfaces 122B and 122C and the surface of the opening 123 for facing the abdominal part closer to the root side than the first joint are included. Hereinafter, both the surfaces 122B and 122C are included. The first surface 121 is inclined with respect to the second surfaces 122B and 122C in a direction in which the first joint of the authentication target finger 3 bends. ing. The first surface 121 is configured as a bottom surface of a recess formed in the upper flat surface 12U of the finger rest 12, and a curved wall 128 is formed at the end in the Y-axis direction. The curved wall 128 is configured such that the radius of curvature increases as the position in the Z-axis direction increases. Each of the second surfaces 122B and 122C is also configured as a bottom surface of a recess formed in the finger rest 12. The opening 123 is provided in a state of penetrating in the Z-axis direction. In the figure, point A is the tip position of the first surface 121, that is, the base portion of the wall 128 and is substantially in the center in the X-axis direction, and point B is the second where the end portion intersects the first surface 121. The point C is an intersection position with the surface 122B of the second surface 122B and is approximately the center position in the X-axis direction, and the point C is an end position of the second surface 122C and is approximately the center position in the X-axis direction. A protrusion 127 serving as a finger position determining unit is provided on the straight line connecting the points A and B in the first surface 121. The dimensions of the first surface and the second surface are the same as in the case of the first embodiment. For example, the distance between the point A and the point B is 5 as the dimension of the first surface. ˜30 × 10 ⁻³ m, for example, about 20 × 10 ⁻³ m, and the dimension of the second surface is, for example, a distance between the point B and the point C of 20 to 50 × 10 as a value of ^-3 m and in example, about 40 × ^{10 -3} m.

  In FIG. 6, the authentication target finger 3 moves in the direction of arrow E and passes through points A, B, and C within the first surface 121 and the second surfaces 122B and 122C of the finger rest 12. Placed along. In the placed state, the authentication target finger 3 is in a state where the first joint is naturally bent corresponding to the inclined state between the first surface 121 and the second surfaces 122B and 122C, The ventral portion on the distal end side of the first joint abuts on the protrusion 127 in the first surface 121 along the line connecting the points A and B, and the ventral side on the root side of the first joint. The portion is placed on the second surfaces 122B and 122C along the line connecting the points B and C. In this state, the portion where the blood vessel (finger vein) is imaged is located above the opening 123 in the abdominal portion closer to the root than the first joint of the finger 3 to be authenticated. Since the authentication target finger 3 is in a state where the first joint is naturally bent as described above, the muscle contracts in the finger 3 at the root side of the first joint, resulting in poor blood flow. Also, the surface of the finger 3 is not pressed. In particular, since a portion where a blood vessel (finger vein) is photographed is placed on the upper portion of the opening 123, the finger surface is not brought into contact with the finger rest 12 and the finger surface is released. For this reason, when infrared light or near infrared light from the light source 11 is transmitted through a portion where a blood vessel (finger vein) is photographed, a clear blood vessel (finger vein) image is formed. A clear image can be formed by photographing. Further, the authentication target finger 3 is engaged with a recess having the second surface 122B as a bottom surface at the point B position, and is engaged with a recess with the second surface 122C as a bottom surface at the point C position. The positioning of the target finger 3 in the Y-axis direction as well as the positioning in the X-axis direction is possible, and rotation around the Y-axis direction can be easily suppressed.

Also in FIG. 6, the inclination angle of the first surface 121 with respect to the second surfaces 122B and 122C is an angle at which the first joint of the authentication target finger 3 is naturally bent. For example, when the angle is in the range of 10 to 45 °, the amount of lift of the second joint in the Z-axis direction can be reduced, and fluctuations in the position of the authentication target finger 3 in the Z-axis direction can be suppressed. . Moreover, the X-axis direction length of 2nd surface 122B, 122C shall be about 7-10 * 10 <^-3> m, for example. Further, the protrusion 127 as the finger position determining means has outer dimensions of a diameter of 0.2 to 10 × 10 ⁻³ m and a height of 0.2 to 10 × 10 ⁻³ m. 0.0 × 10 ⁻³ m and a height of about 1.0 × 10 ⁻³ m. The protrusion 127 is provided, for example, at a position 5 to 10 × 10 ⁻³ m from the B point position. With this configuration, the finger placement table 12 of the authentication target finger 3 can be easily positioned in the Y-axis direction. As the finger position determining means, a protruding sensor or switch may be provided instead of the protruding portion 127. In the case of the protrusion-shaped sensor or switch, for example, when the corresponding part of the finger 3 to be authenticated touches the protrusion-shaped sensor or switch, the light emission operation by the light source 11 or the photographing by the camera 13 is performed in the apparatus. A signal for starting the operation of the apparatus such as an operation is output, and conversely, when the corresponding part of the authentication target finger 3 is not in contact with the protruding sensor or switch, the apparatus operation is not started. To.
As in the case of the first embodiment, a filter member that allows infrared light or near infrared light to pass through and blocks other light may be provided in the opening 123.

  Also by the personal authentication apparatus of the fourth embodiment of the present invention using the finger rest 12 of FIG. 6 in the imaging unit, a clear finger vein image and a clear captured image of the finger 3 to be authenticated are obtained, Authentication accuracy can be improved, and accurate personal authentication can be easily performed. The finger rest 12 has a simple configuration, and a photographing unit including the finger rest can be configured at a relatively low cost, and an increase in apparatus cost can be suppressed. In particular, in the finger rest 12 of FIG. 6, the inclined first surface 121 includes the protrusion 127 inside, and the second surfaces 122B and 122C are configured as the bottom surfaces of the respective recesses. 3 is easy to position with respect to the finger rest 12.

  In each of the above embodiments, the collation unit 21 and the recording unit 22 are provided in the personal computer / monitor 2. However, the present invention is not limited to this. Moreover, although the light source 11 was set as the structure arrange | positioned with respect to the finger placement stand 12 in the position which pinches | interposes the authentication object finger | toe 3 in between, this invention is not limited to this. The light that forms the blood vessel image may be taken into the camera 13 as transmitted light that has passed through the authentication target finger 3, or may be taken into the camera 13 as reflected light from the authentication target finger 3. Furthermore, the photographing unit 1 may be provided as a single unit or may be integrated into a housing of a personal computer or an electronic device, for example.

  In each of the above embodiments, as the configuration of the finger rest 12, the first surface is inclined with respect to the second surface in the direction in which the first joint of the finger to be authenticated is bent. The present invention is not limited to this, and the first surface is lower than the second surface in the direction in which the first joint of the finger to be authenticated bends without being inclined with respect to the second surface. It may be a configuration arranged at a position.

1 is a configuration example diagram of a personal authentication device as a first embodiment of the present invention. It is a perspective view which shows the structural example of the finger rest used for the personal authentication apparatus of FIG. It is a side view of the finger rest used for the personal authentication apparatus of FIG. It is explanatory drawing of the finger rest used for the personal authentication apparatus as 2nd Example of this invention. It is explanatory drawing of the finger rest used for the personal authentication apparatus as 3rd Example of this invention. It is explanatory drawing of the finger rest used for the personal authentication apparatus as the 4th Example of this invention. It is explanatory drawing of the subject of this invention. It is explanatory drawing of the subject of this invention. It is explanatory drawing of the subject of this invention. It is explanatory drawing of the subject of this invention.

Explanation of symbols

1 ... Shooting unit,
2 ... PC / monitor,
3 ... Finger for authentication,
11 ... Light source,
12 ... Finger rest,
13 ... Camera,
21 ... collation part,
22 ... Recording section,
23 ... Display / notification unit,
24 ... Power supply,
100 ... personal authentication device,
121 ... the first surface,
122, 122B, 122C ... the second surface,
123 ... opening,
125, 126, 127 ... projections,
128 ... the wall.

Claims (6)

A personal authentication device that performs personal authentication based on a finger vein image,
A first surface for contacting the abdominal portion on the distal end side of the first joint of the finger to be authenticated, and a second surface for facing the abdominal portion on the root side of the first joint. A finger rest that is arranged at a position where the first surface is lowered in a direction in which the first joint of the finger to be authenticated is bent with respect to the second surface;
A light source that emits infrared light or near infrared light to the second surface side of the finger rest;
A camera that captures an image of a finger vein formed by the infrared light or near infrared light;
A personal authentication device comprising:   2. The personal authentication device according to claim 1, wherein the finger placing table is configured such that the first surface is inclined with respect to the second surface in a direction in which a first joint of a finger to be authenticated is bent.   The personal authentication device according to claim 1, wherein the finger rest is configured to include finger position determination means for determining a finger position in the first surface.   The finger rest is configured such that the finger position determining means is configured using a switch or a sensor, and when the finger position is determined, the camera starts photographing based on the operation of the switch or the sensor. Item 4. The personal authentication device according to Item 3.   5. The personal authentication device according to claim 2, wherein the finger placement table has a configuration in which the first surface is inclined with respect to the second surface at an angle in a range of 10 ° to 45 °. . The personal authentication device according to claim 1, wherein the finger placing table has a configuration in which the second surface is a concave curved surface along an outer periphery of a finger.

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