JP2007301058A - Individual authentication device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a configuration of an individual authentication device which shows user-friendliness and has high authentication precision in individual authentication using images of digital veins. <P>SOLUTION: The individual authentication device prevents rotations and shift of the finger to be authenticated in the lateral or longitudinal direction by providing a guide which uses a position of a bifurcated portion at the base between fingers as a reference for positioning the finger. The authentication precision is improved by acquiring images of digital veins with high reproducibility to individual physical variations. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an apparatus for biometric authentication, and more particularly to an apparatus for personal authentication or identification using finger vein image data.

  Personal authentication using human biometric information includes information that uses information (data) such as fingerprints and irises, but finger vein authentication technology that uses images of veins inside human fingers is the focus of attention. Has been. Patent Document 1 discloses a method for performing personal authentication using finger vein image data, and a case provided with an insertion portion that allows a fingerprint of one finger to be inserted toward the lower surface and the finger transmitted through the upper surface. A light source unit that generates light, an interference filter unit that transmits light with respect to an arbitrary wavelength, an imaging unit that captures transmitted light that has passed through the interference filter unit, and the finger vein output from the imaging unit Disclosed is a personal authentication device that includes an image processing unit that creates collation data capable of collating image data with prestored image data.

  The finger to be authenticated is positioned by inserting the finger to be authenticated into the insertion portion, the depth is abutting the tip of the finger against the finger abutting portion, and the left and right direction is guided by the upper finger base abutting portion. The left / right rotation is to make visual adjustment so that the center of the back of the finger is aligned with a triangular mark provided at a visible position.

JP 2004-049705 A

  In Patent Document 1 described above, the light source unit is arranged on the upper part of the finger to be recognized and covers the insertion unit, so that the external light can be blocked. However, the user inserts the finger into the insertion unit where the inside cannot be seen. It is necessary to align the tip of the finger with the protrusion by groping. Moreover, inserting a finger into the opening where the inside cannot be seen gives the user anxiety. In addition, there is a drawback in that the finger vein image data cannot be obtained with high reproducibility, and the personal authentication accuracy is lowered because the finger rotation is visually adjusted to prevent the finger from rotating in the left-right direction. Furthermore, if a protrusion serving as a wall is provided as a guide at the tip of the finger in order to acquire finger vein image data of the fingertip half, the protrusion is an obstacle for a person with a long nail. On the other hand, there is a contradiction that even if a person with a long nail is made small so that the protrusion does not get in the way, the effect as an alignment guide for the finger tip is lost. As another problem, it can be considered that the finger tip does not reach the protrusion for a person with short fingers.

  An object of the present invention is to solve any one or more of the above-described problems. For example, by acquiring vein image data of the base half of the finger instead of acquiring vein image data of the half of the fingertip, it is highly reproducible even for individuals with physical variations, that is, those with long fingers and nails It is an object of the present invention to provide a finger vein authentication device that can acquire a finger vein image with certainty.

  The present invention includes a case provided with an open finger installation portion that can be placed with the belly surface of the finger facing down, a light source portion that generates transmitted light from both sides of the finger, and an arbitrary wavelength. An interference filter unit having a light transmission property only, an imaging unit that images the transmitted light that has passed through the interference filter unit, and image data that stores vein image data of the finger output from the imaging unit in advance. It exists in the imaging device or personal authentication device to be collated.

  In addition, the finger installation portion includes a protrusion that determines the position of the finger and the “male” of the finger, and a protrusion that supports the tip half of the finger. It is desirable to arrange the protrusions that determine the position of the “to” between the fingers such that the root portion of the finger is located directly above the interference filter portion from the second joint which is the original half of the finger in the longitudinal direction. .

  That is, when the finger is placed on the finger installation part of the authentication device, the finger long axis direction deviation, the finger short axis direction deviation (finger left and right deviation), and the finger vein image capturing unit are prevented from being displaced, It is necessary to increase the reproducibility of finger vein data reading by making the imaging surface of each finger the same. Therefore, in order to prevent displacement in the finger long axis direction, a protrusion that determines the position of the “to” between the finger and the finger is provided, and in order to prevent displacement in the finger short axis direction, a protrusion that supports the root and tip half of the finger is provided. The protrusion shape is a round shape similar to the finger shape. Furthermore, in order to prevent rotation about the finger long axis, a plurality of protrusions for supporting the base portion of the finger are provided.

  In particular, the method of preventing rotation around the long axis of a finger is difficult to prevent rotation even if only one finger is supported, and even if the fingertip halves of multiple fingers are supported at the same time, Rotate in the direction of rotation about the long axis of the finger, the fingertip half will be rotated together. That is, the rotation of the finger is solved not by supporting only the half of the fingertip but by supporting the roots of a plurality of fingers so as not to rotate. The finger bases may support the bases of all the fingers. However, if a plurality of finger bases adjacent to the finger bases to be imaged can be supported simultaneously, the rotation of the fingers can be restricted.

  According to the present invention, in personal authentication using a finger vein image, positioning is performed when a finger is placed at the “to” of the finger and the base of the finger, and a plurality of joints at the base of the finger are simultaneously supported. By acquiring finger vein image data at the base half of the finger while suppressing rotation, finger vein images can be obtained with high reproducibility even for individuals with long physical and finger nails It is possible to provide a personal authentication device with high authentication accuracy.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

  1 is an external perspective view of the personal authentication device, FIG. 2 is a view of the image pickup unit viewed from the front side with the finger placed on the personal authentication device of FIG. 1, and FIG. 3 is a view of the personal authentication device of FIG. The figure which looked at the image pick-up part from right above in the state where it put down is illustrated. Note that it is desirable that this personal authentication device is placed on the operation surface of an automatic machine, for example, and used together with or in place of a personal identification number. Automatic machines include, for example, ATMs (Automatic Teller Machines), CDs (Cash Dispensers), etc. installed at branches of financial institutions such as banks, post offices, and consumer finance companies. This is an automatic transaction apparatus. In addition, use of credits at automatic ticket machines installed at railway stations, road stations, bus stops, highway service areas and parking areas, amusement halls, theaters, museums, parking lots, restaurants, sports facilities, etc. It may be personal authentication. In addition to automatic machines, it is desirable to install in locations where it is necessary to prevent unauthorized entry and exit such as safe entrances in financial sales offices and residence entrances, and use them in a form that authenticates individuals. The following example has a control unit that performs image processing on finger vein image data captured by the personal authentication device and collates with registered personal data, but this control unit may be provided outside the device, Since it is sufficient if the finger vein data can be imaged, it is also simply called an imaging device.

  As shown in FIG. 1, the personal authentication apparatus covers the mounted devices with an upper case 1 and a lower case 2, and the light source mounting unit 3 is located at two locations on the left and right from the upper case 1, that is, one pair is above the surface of the upper case 1. Protruding. The light source mounting part 3 has a light source irradiation window 4 so that both the left and right sides face each other. As shown in the figure, the upper case 1 is open so that the abdominal surface of the finger can be placed downward, so that the user is less anxious than a method in which the finger is inserted into a certain part. However, if the upper part is an open structure, in addition to the light source necessary for imaging, it is recognized by the influence of external light that causes disturbances in imaging, such as fluorescent lights in financial stores, and when installed near the entrance of the store, such as West Japan There is concern about a decline in the rate. Since the authentication target finger 10 is arranged on the upper surface of the interference filter 5 in the illustrated personal authentication device, the light source mounting unit 3 is not affected by disturbance light from the upper surface of the device. It is arranged with a height sufficient to block ambient light. On the finger base side, a “middle” position guide 7 is provided which is integrated with the shape of the light source mounting portion 3 to position the “male” between the fingers. Here, as the installation position of the “middle” position guide, a position where the finger vein imaging of the finger half of the finger can be performed, that is, the finger root portion from the second joint which is the original half of the finger in the longitudinal direction is an interference filter. It is desirable to arrange so that it is located directly above the part. Further, the finger base guide 6 that supports the finger base is disposed in a form that is integrated with the “or” position guide 7 and that eliminates a gap into which light is inserted. In addition, on the finger tip side in the finger vein imaging range, the finger tip side support guide 8 is disposed so as to be integrated with the light source mounting portion 3 and without a gap into which light is inserted. By adopting the above structural features, it is possible to suppress a decrease in the recognition rate due to ambient light without giving the user a sense of anxiety of inserting a finger into an invisible part.

  Next, there is an interference filter 5 on the surface sandwiched between the light source mounting portions 3, and the interference filter 5 is a glass or resin sheet that can transmit only near infrared rays. A finger base support guide 6 that supports the finger base is disposed in front of the interference filter 5, and a finger tip side support guide 8 that supports the finger tip side is disposed behind the interference filter. At one or both of the finger base support guide 6 and the finger tip side support guide 8 in the short direction center part, a finger is projected with a braille protrusion to indicate the finger short direction center position. A short direction center position guide 9 is provided.

  The finger is placed on the authentication device so that the “again” between the index finger and the base of the middle finger and the “me” between the middle finger and the base of the ring finger are brought into contact with the “position” position guide 7 as indicated by a two-dot chain line. Put on. In this way, the position in the finger long axis direction is determined. In the case of an authentication device in which a finger is placed by finger tip alignment, it is conceivable that the finger cannot reach the finger tip alignment unit for a person with a short finger. In this state, even if the base portion of the finger is in contact with the base guide, the tip portion of the finger is floating, so the distance from the imaging unit is not stable, and as a result, the recognition rate may decrease. Further, even for a person with a long nail, it is conceivable that the finger tip position guide interferes with the nail when the finger tip is aligned, and the finger cannot be stably placed on the authentication device. On the other hand, the finger grounding method based on the finger and the finger "male" of the present invention stabilizes the position of the finger in the long axis direction to the authentication device regardless of whether the finger or nail is long or short. Determined. Furthermore, since the finger is grounded so that the position guide 7 is sandwiched between the finger to be authenticated and the adjacent finger, rotation about the finger long axis can also be suppressed.

  Further, the base of the finger is grounded to the finger base support guide 6, and the tip of the finger is grounded to the finger tip side support guide 8. By doing so, disturbance light can be prevented from entering, and a reduction in recognition rate can be suppressed. In addition, since the ground is grounded at both the finger base and the finger tip side, the distance from the imaging unit is also stably determined with the middle finger floating. Further, when the finger is brought into contact with the finger base support guide 6 and the finger tip side support guide 8, the position of the finger in the short axis direction of the finger is adjusted by aligning the center position of the finger in the short direction with the center position guide 9 in the short direction of the finger. (Left and right positions of the finger) are determined. Here, when the finger base support guide 6 and the finger tip side support guide 8 are formed in an R shape reminiscent of the finger placement position, the user can easily understand the finger placement position.

  As described above, by simply placing the finger in accordance with the “middle” position guide 7, the finger base support guide 6, the finger tip side support guide 8, and the finger lateral direction center position guide 9 that regulate the finger placement position, Even if there is a physical variation in individuals, such as a long person, a short person, a person with a long nail, or a person with a long nail, the finger is placed on the finger installation part of the authentication device. It is possible to prevent misalignment in the minor axis direction (left and right direction) and positional deviation from the finger image capturing unit of the finger, and to make the finger imaging surface the same every time, thereby improving the reproducibility of finger vein data reading.

  1 to 4, the middle finger is the authentication target finger 10, but since the present invention has an open planar case shape, there is no restriction to specify the finger, so if it is a finger of the hand, all right and left The finger can be the authentication target finger 10. For example, for a person with a small hand or a person with a thin finger, the middle finger is used as the authentication target finger 10, and the index finger or the ring finger and the base of the index finger or the ring finger are brought into contact with the position guide 7, and the index finger is used as the authentication target finger. 10, it is also conceivable that it is easier to place a finger when only “or” at the base of the finger with the middle finger abuts against the “position” position guide 7. Therefore, by making it possible to designate the finger that is most easily operated by the user as the authentication target finger 10, positioning when placing the finger on the authentication device is facilitated, and as a result, a finger vein image is obtained with high reproducibility. And high authentication accuracy can be obtained.

  As described above, according to the present embodiment, in personal authentication using a finger vein image, positioning is performed when a finger is placed with a finger “finger”, and finger vein image data of the base half of the finger is obtained. Obtaining a personal authentication device that can acquire finger vein images with high reproducibility even for individuals with long and short fingers and nails, and with high authentication accuracy it can.

  FIG. 4 shows an example in which the shape of the finger base support guide 6 is extended in the finger short axis direction (left-right direction). FIG. 5 is a view of the imaging unit viewed from the front side with a finger placed on the personal authentication device of FIG. The authentication target finger 10, for example, the middle finger is placed in the same manner as in FIG. 1, and the finger 12 adjacent to the authentication target finger, for example, the base of the index finger and the ring finger is grounded to the finger base support guide extension 11, Not only the position guide 7 is sandwiched between the fingers 12 adjacent to the authentication target finger, but also the three joints at the base of the finger are supported, and the suppression of the rotation of the finger in the left-right direction can be improved. Here, it is desirable that the shape of the finger base support guide extension 11 is an R shape reminiscent of a finger placement position.

It is an external appearance perspective view of a personal authentication device. It is the figure which looked at the image pick-up part from the near side in the state where a finger was put on the personal authentication device of FIG. It is the figure which looked at the imaging part from right above in the state where a finger was put on the personal authentication device of FIG. It is an external view which shows the other Example of a personal authentication apparatus. It is the figure which looked at the image pick-up part from the near side in the state where a finger was put on the personal authentication device of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Upper case, 2 ... Lower case, 3 ... Light source mounting part, 4 ... Light source irradiation window, 5 ... Interference filter, 6 ... Finger root support guide, 7 ... "Position" position guide, 8 ... Finger tip side support guide, 9 ... Guide position in the lateral direction of the finger, 10 ... Finger for authentication, 11 ... Finger root support guide extension, 12 ... Finger adjacent to the finger for authentication.

Claims (5)

  An imaging apparatus for imaging a vein of a finger, wherein the authentication target finger is placed on the basis of the position of the finger and the base of the finger.   The imaging apparatus according to claim 1, further comprising a protrusion that determines a position of a “male” of a finger and a base of the finger.   The imaging apparatus according to claim 1, further comprising a protrusion that supports a root of the finger to be authenticated.   The imaging apparatus according to claim 1, further comprising a protrusion that supports a finger tip side outside a range in which a finger vein is imaged. The imaging apparatus according to claim 3, wherein a projection is provided that supports not only the finger to be authenticated but also the root of one or both adjacent fingers.

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