JP2015225354A - Biometric authentication device, biometric authentication method, biometric authentication program, and electronic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a biometric authentication device or the like capable of improving authentication accuracy.SOLUTION: A biometric authentication device comprises: an imaging part which acquires a palm image being an image including at least a part of a palm of a living body; a finger region extraction part which extracts a plurality of finger region images from a palm image acquired from the imaging part; a vein pattern detection part which detects a plurality of finger vein patterns based on the plurality of finger region images extracted by the finger region extraction part; a vein pattern collation part which collates the plurality of finger vein patterns detected by the vein pattern detection part with a registered vein pattern of fingers which is previously registered; and an authentication part which obtains a final personal authentication result by performing total determination based on an individual collation result of the plurality of finger vein patterns in the vein pattern collation part.

Description

  The present invention relates to a biometric authentication device, a biometric authentication method and a biometric authentication program for performing personal authentication using a vein or the like in a biometric finger, and an electronic apparatus including such a biometric authentication device.

  In recent years, biometric authentication has attracted attention from the viewpoint of security. In particular, an authentication technique (vein authentication technique) using a biological vein pattern has advantages that authentication accuracy is high and counterfeiting is difficult. A biometric authentication device (personal authentication device) using such a vein authentication technique is disclosed in, for example, Patent Document 1.

JP 2004-78791 A

  By the way, such a biometric authentication device is generally required to improve authentication accuracy. Therefore, a proposal of a method for improving authentication accuracy is desired.

  The present invention has been made in view of such problems, and an object thereof is to provide a biometric authentication device, a biometric authentication method, a biometric authentication program, and an electronic apparatus that can improve authentication accuracy.

  The biometric authentication device of the present invention includes an imaging unit that acquires a palm image that is an image including at least a part of a palm of a biological body, and finger regions that respectively extract a plurality of finger region images from the palm image acquired by the imaging unit. An extraction unit, a vein pattern detection unit that detects a plurality of finger vein patterns based on the plurality of finger region images extracted by the finger region extraction unit, and a plurality of finger veins detected by the vein pattern detection unit By performing a comprehensive judgment based on a vein pattern matching unit that matches a pattern and a registered vein pattern of a finger registered in advance, and individual matching results of a plurality of finger vein patterns in the vein pattern matching unit And an authentication unit for obtaining a final personal authentication result.

  The electronic device of the present invention includes one or a plurality of the biometric authentication devices of the present invention.

  According to the biometric authentication method of the present invention, an imaging step for acquiring a palm image that is an image including at least a part of a palm of a biological body, and finger area extraction for extracting a plurality of finger area images from the palm image acquired in the imaging step, respectively. A vein pattern detection step for detecting a plurality of finger vein patterns based on the plurality of finger region images extracted in the finger region extraction step, and a plurality of finger vein patterns detected in the vein pattern detection step, The final personal authentication result is obtained by making a comprehensive judgment based on the vein pattern matching step for matching the registered vein pattern of the finger and the individual matching results of the plurality of finger vein patterns in this vein pattern matching step. And an authentication step to be obtained.

  The biometric authentication program according to the present invention includes an imaging step for acquiring a palm image that is an image including at least a part of a palm of a biological body, and finger area extraction for extracting a plurality of finger area images from the palm image acquired in the imaging step. A vein pattern detection step for detecting a plurality of finger vein patterns based on the plurality of finger region images extracted in the finger region extraction step, and a plurality of finger vein patterns detected in the vein pattern detection step, The final personal authentication result is obtained by making a comprehensive judgment based on the vein pattern matching step for matching the registered vein pattern of the finger and the individual matching results of the plurality of finger vein patterns in this vein pattern matching step. The authentication step to be obtained is executed by a computer.

  According to the biometric authentication device, the biometric authentication method, the biometric authentication program, and the electronic device of the present invention, it is possible to improve the authentication accuracy.

It is a block diagram showing the schematic structural example of the biometrics apparatus which concerns on one embodiment of this invention. It is a schematic diagram showing an example of the acquisition method of the palm pattern shown in FIG. It is a schematic diagram showing the other example of the acquisition method of the palm pattern shown in FIG. It is a block diagram showing schematic structure of the biometrics apparatus which concerns on a comparative example. It is a flowchart showing an example of the personal authentication operation | movement which concerns on embodiment. It is a schematic diagram showing an example of the image and pattern used in the case of the personal authentication operation | movement shown in FIG. It is a flowchart showing an example of the personal authentication operation | movement which concerns on a modification. It is a block diagram showing the example of application to the electronic device of a biometrics apparatus.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The description will be given in the following order.
1. Embodiment (Example of personal authentication using the result of collation of a palm pattern)
2. Modified example (example of collating palm-shaped patterns before collating multiple finger vein patterns)
3. Application example (application example of biometric authentication device to electronic equipment)
4). Other variations

<1. Embodiment>
[Constitution]
FIG. 1 is a block diagram illustrating a schematic configuration example of a biometric authentication device (biometric authentication device 1) according to an embodiment of the present invention. The biometric authentication device 1 includes a light source unit 10, an imaging unit 11, a finger region extraction unit 121, a vein pattern detection unit 122, a vein pattern status determination unit 123, a vein pattern verification unit 124, a palm pattern acquisition unit 131, and a palm pattern. A collation unit 134 and an authentication unit 14 are provided. Note that the biometric authentication method and the biometric authentication program according to the embodiment of the present invention are each embodied in the biometric authentication device 1 of the present embodiment, and thus will be described together.

  As shown in FIG. 1, the light source unit 10 is a light source (near infrared light source) that emits near infrared light Lir toward the palm p of a living body (human being a user) to be authenticated. Such a near-infrared light source is configured using, for example, a light emitting diode (LED). As the wavelength region of the near infrared light Lir, for example, it is desirable to use a near infrared region (a wavelength region of about 700 nm to 1200 nm). This is because it is easy to acquire a vein pattern image in the vein pattern detection unit 122 described later by utilizing the property that hemoglobin contained in the vein of the living body (palm p) easily absorbs near-infrared light.

  The imaging unit 11 acquires a palm image Ip that is an image including at least a part of a palm p (palm) of a living body. That is, the palm image Ip may be not only an image of the entire palm p but also an image of a part of the palm p (for example, an image in which some finger areas such as a thumb are missing from the entire palm p). In this example, the imaging unit 11 uses the near infrared light Lir emitted from the light source unit 10 to acquire the palm image Ip. Such an imaging unit 11 is configured using, for example, an imaging element (image sensor) such as a charge coupled device (CCD) or a complementary metal oxide semiconductor (CMOS).

  The finger area extraction unit 121 executes a plurality of (in this example, corresponding to the image of the area where each finger is located in the palm p from the palm image Ip acquired by the imaging unit 11 by executing predetermined image processing, for example. 5) finger region images If are respectively extracted. At this time, as indicated by a dashed arrow in FIG. 1, the finger area extraction unit 121 refers to, for example, a palm pattern Pps acquired by a palm pattern acquisition unit 131 described later (included in the palm pattern Pps). Each finger region image If is extracted from the palm image Ip.

  The vein pattern detection unit 122 performs a plurality of (five in this example) finger vein patterns Pfv1 based on the plurality of finger region images If extracted by the finger region extraction unit 121, for example, by executing predetermined image processing. Are respectively detected. Here, the following is mentioned as an example of the image process which extracts each finger vein pattern Pfv1 from the finger area | region image If which is a gray scale image. That is, first, the vein pattern detection unit 122 performs processing for enhancing the edge region in the finger region image If. Examples of the edge enhancement method at this time include a method using an image filter such as a Gaussian filter or a Laplacian filter. Next, the vein pattern detection unit 122 performs a process of removing noise in the image after the edge enhancement process using an image filter such as a median filter, and then uses a predetermined threshold to perform the process after the noise removal process. Binarization processing is performed on the image. The vein pattern detection unit 122 can finally extract each finger vein pattern Pfv1 by performing thinning processing, which is general image processing, on the binarized image.

  The vein pattern status determination unit 123 determines a pattern status (a priority distribution status described later) in the plurality of finger vein patterns Pfv1 detected by the vein pattern detection unit 122. In this example, the vein pattern status determination unit 123 automatically selects a part of the finger vein patterns Pfv1 that are expected to be suitable for finger vein authentication among the plurality of detected finger vein patterns Pfv1. More specifically, in this example, the vein pattern status determination unit 123 automatically selects a finger vein pattern Pfv1 having a relatively high priority among the plurality of finger vein patterns Pfv1, although details will be described later. It is like that. A part of the finger vein pattern Pfv1 selected in this way is output as a finger vein pattern Pfv2.

  The vein pattern matching unit 124 includes a plurality of finger vein patterns Pfv2 detected by the vein pattern detection unit 122 and selected by the vein pattern status determination unit 123, and a registered vein pattern Pfv0 of each finger in the palm p registered in advance. Are collated with each other. Specific examples of the collation method include the following. That is, for example, the vein pattern matching unit 124 calculates the similarity between each finger vein pattern Pfv2 and each registered vein pattern Pfv0, and compares the calculated similarity of each finger with a predetermined threshold. Thus, a matching result for each finger is obtained. An example of a method for calculating the similarity at this time is a method using cross-correlation values in two images (finger vein pattern Pfv2 and registered vein pattern Pfv0). Note that it is desirable to perform finger position correction processing as necessary when calculating such similarity. Here, as described above, since some of the finger vein patterns Pfv1 are automatically selected by the vein pattern status determination unit 123, the vein pattern matching unit 124 has priority among the plurality of finger vein patterns Pfv1. The finger vein pattern Pfv1 having a relatively high degree is selectively used as the vein pattern Pfv2. The collation result is output as collation result data Cfv.

  The palm pattern acquisition unit 131 acquires a shape pattern (palm pattern Pps) of the palm p of the living body. As a method for obtaining the palm pattern Pps, for example, the following two methods can be cited.

  In the first method, for example, as schematically illustrated in FIG. 2A, the touch sensor 15 disposed on the liquid crystal panel 16 is used as the palm pattern acquisition unit 131, for example, and the detection result of the touch sensor 15 is detected. Is used to acquire the palm pattern Pps. As the touch sensor 15, various touch sensors such as a capacitance type, an optical type, and a contact type can be used.

  The second method is to acquire the palm pattern Pps using image processing on the palm image Ip acquired by the imaging unit 11 as schematically shown in FIG. 2B, for example. . In other words, in this method, the image processing unit 131A in the palm pattern acquisition unit 131 performs image processing on the palm image Ip to generate a palm pattern Pps. As an example of a method for extracting the palm pattern Pps by such image processing, there is a method for detecting a skin color region in a palm image Ip composed of a multicolor image. Another example is a method of performing edge detection in a palm image Ip made of a gray scale image obtained by imaging using near infrared light Lir. An example of the edge detection technique is a technique using a Laplacian filter, which is a general image processing technique.

  2A and 2B, for example, guide display for guiding (instructing) the placement area of the palm p may be performed on the liquid crystal panel 16, for example. In this case, the displacement of the placement area of the palm p (positional displacement every time it is placed) is suppressed, and the authentication accuracy is improved.

  The palm shape pattern collating unit 134 collates the palm shape pattern Pps acquired by the palm shape pattern acquiring unit 131 with the registered palm shape pattern Pps0 in the palm p registered in advance. The result collated in this way is output as collation result data Cps.

  The authentication unit 14 makes a comprehensive determination based on the individual matching results (matching result data Cfv) of the plurality of finger vein patterns Pfv2 in the vein pattern matching unit 124, whereby the authentication result as the final personal authentication result Data Bout is obtained and output. At this time, the authentication unit 14 makes a comprehensive determination in consideration of the individual priority levels in the plurality of finger vein patterns Pfv2. Further, particularly in the present embodiment, the authentication unit 14 makes such a comprehensive determination using the collation result (collation result data Cps) in the palm pattern matching unit 134. That is, comprehensive judgment is performed in consideration (integrated) of both the matching result data Cfv of the finger vein pattern Pfv2 and the matching result data Cps of the palm pattern Pps. The details of the comprehensive judgment method (personal authentication method) in the authentication unit 14 will be described later.

  It should be noted that at least a part of the above-described finger region extraction unit 121, vein pattern detection unit 122, vein pattern status determination unit 123, vein pattern verification unit 124, palm pattern acquisition unit 131, palm pattern pattern verification unit 134, and authentication unit 14 Each is configured using, for example, a microcomputer.

[Action / Effect]
(A. Basic operation)
In this biometric authentication device 1, when the palm p of a living body to be authenticated is placed in the vicinity, the imaging unit 11 acquires a palm image Ip that is an image including at least a part of the palm p. Then, based on the palm image Ip, a collation process (collation process with a registered pattern registered in advance) is performed, and personal authentication is performed based on the collation result.

  Specifically, when a collation result indicating that it matches the registered pattern is obtained, the biometric authentication device 1 outputs authentication result data Bout indicating that the personal authentication is successful. On the other hand, when a collation result indicating that it does not match the registered pattern is obtained, the biometric authentication device 1 outputs authentication result data Bout indicating that personal authentication has failed.

(B. Detailed personal authentication operation)
Next, details of the personal authentication operation in the biometric authentication device 1 will be described in comparison with a comparative example (a general biometric authentication device using a finger vein pattern).

(Comparative example)
FIG. 3 is a block diagram illustrating a schematic configuration of a biometric authentication device (biometric authentication device 100) according to a comparative example. The biometric authentication device 100 of this comparative example includes a light source unit 10, an imaging unit 101, a vein pattern detection unit 122, a vein pattern matching unit 124, and an authentication unit 104.

  The imaging unit 101 uses the near infrared light Lir emitted from the light source unit 10 to acquire an image of the biological finger f (finger region image If). The vein pattern detection unit 122 detects a finger vein pattern Pfv based on the finger region image If by executing predetermined image processing. The vein pattern collating unit 124 collates this finger vein pattern Pfv with a registered vein pattern Pfv0 of a finger registered in advance. The authentication unit 104 obtains and outputs authentication result data Bout as a personal authentication result based on the matching result (matching result data Cfv) of the finger vein pattern Pfv in the vein pattern matching unit 124.

  In such a biometric authentication device 100, in order to acquire finger vein information (finger vein pattern Pfv), it is necessary to place a biometric finger f to be authenticated at a predetermined position. However, when the finger f is placed, misalignment (position misalignment of the placement area of the finger f, angular misalignment due to the rotation of the finger f itself, etc.) is likely to occur, resulting in a decrease in authentication accuracy.

  In addition, placing the finger f in the correct position requires a special operation for personal authentication. For example, it is not easy for an elderly person or the like to place the finger f correctly, and the convenience is inferior. Become.

(This embodiment)
Therefore, in the biometric authentication device 1 of the present embodiment, a plurality of finger region images If are respectively extracted from the palm image Ip acquired by the imaging unit 11, and a plurality of finger vein patterns are based on the plurality of finger region images If. Pfv1 is detected, and personal authentication is performed based on the plurality of finger vein patterns Pfv1.

  Here, when the palm p is placed, the degree of freedom of arrangement becomes lower in principle compared to when the finger f is placed (the finger is not easily rotated or angularly displaced when placed). Compared with the comparative example, the authentication accuracy is improved. Further, since the positional deviation of the palm p is easier to detect than the positional deviation of the finger f, it can be said that the authentication accuracy is improved in this embodiment as compared with the comparative example. Furthermore, since the degree of freedom in arrangement becomes low, in other words, the burden on the user that it must be placed in the correct position is reduced, so that the present embodiment also improves convenience compared to the comparative example. .

In addition, in the biometric authentication device 1 of the present embodiment, the authentication unit 14 makes a final determination by making a comprehensive determination based on the individual verification results of the plurality of finger vein patterns Pfv2 in the vein pattern verification unit 124. Authentication result data Bout as a result of personal authentication is acquired. Thereby, for example, compared with the case where a personal authentication result is obtained based on, for example, the number of simple fingers (the number of fingers that have been successfully verified), the authentication accuracy can be further improved. Specifically, when the personal authentication result is obtained based on the number of fingers, etc., the authentication accuracy is inferior to the present embodiment for the following reasons, for example.
-In finger vein authentication, despite the difference in ease of authentication by finger, the personal authentication result is calculated by a simple majority without considering that point.
The detected finger vein pattern varies depending on the shape of the palm (for example, how the hand opens), but this point is not taken into consideration.

  FIG. 4 is a flowchart showing an example of the personal authentication operation according to the present embodiment. 5A to 5E schematically show examples of images and patterns used in the personal authentication operation shown in FIG.

  In this personal authentication operation, first, the imaging unit 11 uses the near infrared light Lir emitted from the light source unit 10 to acquire a palm image Ip that is an image including at least a part of the palm p of the living body (user). (See step S11 in FIG. 4: FIG. 5A). Next, the palm pattern acquisition unit 131 acquires the shape pattern (palm pattern Pps) of the palm p of the living body using, for example, the method shown in FIG. 2A or 2B described above (step S12: FIG. 5 ( E)). At this time, for example, if the palm pattern Pps is a tilted (rotated) image, the palm pattern pattern income unit 131 automatically corrects the tilt of the palm pattern Pps. Is desirable.

  Subsequently, the finger area extraction unit 121 extracts a plurality (five in this example) of finger area images If from the palm image Ip acquired in step S11, for example, by executing predetermined image processing ( Step S13: See FIG. 5B). At this time, as indicated by broken arrows in FIGS. 1 and 5, the finger region extraction unit 121 refers to, for example, the palm pattern Pps acquired in step S12 (for each finger included in the palm pattern Pps). It is desirable to extract each finger region image If from the palm image Ip. This is because it is difficult to extract the finger region image If without using the palm pattern Pps.

  Next, the vein pattern detection unit 122 executes, for example, predetermined image processing, and based on the plurality of finger region images If extracted in step S13, a plurality (five in this example) of finger vein patterns Pfv1 (Step S14: see FIG. 5C).

  Subsequently, the vein pattern status determination unit 123 considers the priority (appropriateness for finger vein authentication), and selects a part (two in this example) of the plurality of finger vein patterns Pfv1 detected in step S14. ) Finger vein pattern Pfv1 is selected as the finger vein pattern Pfv2 (step S15: see FIG. 5D). Here, as schematically shown in FIG. 5D, the finger vein pattern Pfv1 having a relatively large information amount (data amount) is set to have a relatively high priority, The finger vein pattern Pfv1 having a relatively small information amount is set so that the priority is relatively small. Then, as schematically shown in FIG. 5D, the vein pattern status determination unit 123 converts the finger vein pattern Pfv1 having a relatively high priority among the finger vein patterns Pfv1 to the finger vein pattern. Select (adopt) as Pfv2.

  Next, the vein pattern collating unit 124 collates each finger vein pattern Pfv2 selected in step S15 with the registered vein pattern Pfv0 of the finger registered in advance (step S16). At this time, since some finger vein patterns Pfv1 are automatically selected in step S15, the vein pattern matching unit 124 selectively uses and registers the finger vein pattern Pfv1 having a relatively high priority. Collation with the vein pattern Pfv0 is performed.

  Next, the palm pattern matching unit 134 collates the palm pattern Pps acquired in step S12 with the registered palm pattern Pps0 registered in advance (step S17).

  Then, the authentication unit 14 is based on the individual matching result (matching result data Cfv) of the plurality of finger vein patterns Pfv2 in step S16 and the matching result (matching result data Cps) of the palm pattern Pps in step S17. By making a comprehensive determination, a final personal authentication result (authentication result data Bout) is obtained and output (step S18). In this way, a comprehensive determination is made in consideration of both the matching result data Cfv of the finger vein pattern Pfv2 and the matching result data Cps of the palm pattern Pps (finger vein authentication and palm shape authentication are used in combination. ), The authentication accuracy can be further improved.

  Further, at this time, the authentication unit 14 performs a comprehensive determination in consideration of individual priority levels in the plurality of finger vein patterns Pfv2. Specifically, such a comprehensive determination is made based on the collation result (collation result data Cfv) in the finger vein pattern (vein pattern Pfv2) having a relatively high priority selected in step S15 ( (See FIG. 5D above). As a result, personal authentication is performed by selectively using a vein pattern matching result with a finger suitable for finger vein authentication, and in this respect, the authentication accuracy can be further improved.

  Thus, the series of personal authentication operations shown in FIG. 4 is completed.

  As described above, in the present embodiment, a plurality of finger region images If are respectively extracted from the palm image Ip, and a plurality of finger vein patterns Pfv1 are detected based on the plurality of finger region images If, respectively. Since personal authentication is performed based on the finger vein pattern Pfv1, the degree of freedom of arrangement of authentication targets can be reduced. Therefore, it is possible to improve authentication accuracy and improve convenience.

  In addition, since the authentication result data Bout as the final personal authentication result is obtained by making a comprehensive judgment based on the individual matching results of the plurality of finger vein patterns Pfv2, further authentication accuracy can be improved. It is possible to improve.

(Example of comprehensive judgment method)
Here, an example of the comprehensive determination method (personal authentication method) in the authentication unit 14 will be specifically described.

  That is, in this example, first, finger vein patterns Pfv1 and Pfv2 for each finger are binarized images, and a value of “1” is set to a pixel in which a vein exists, and a pixel in which no vein exists. Is assigned a value of “0”. In general, an image with many veins (an image with a high ratio of veins) has a large amount of information, which is suitable for personal authentication. Therefore, as described in detail below, in this example, the vein ratio (ratio of pixels having a value of “1” in the image) corresponding to each finger vein pattern Pfv1, Pfv2 is set to the above-mentioned “priority”. By using and considering as an example, the authentication unit 14 makes a comprehensive determination.

  Here, Table 1 below shows an example of similarity and vein ratio values in the finger vein patterns Pfv1 and Pfv2 of five fingers (thumb, index finger, middle finger, ring finger, and little finger). Note that the similarity means the similarity between each finger vein pattern Pfv2 and each registered vein pattern Pfv0 as described above, and is a parameter calculated by the vein pattern matching unit 124. In addition, in this example, a value of 800 is used as the threshold value for similarity (described above) when the vein pattern matching unit 124 performs matching. In this example, the vein ratio is calculated by the vein pattern status determination unit 123.

  Here, comparing the degree of similarity between each finger and the threshold, the thumb and index finger have a similarity greater than the threshold (= 800) (similarity is relatively large), and the middle finger, ring finger, and little finger The similarity is smaller than the threshold (similarity is relatively small). Therefore, for example, as described above, when obtaining a personal authentication result based on the number of fingers that have been successfully collated, two of the thumb and forefinger are successfully collated (determined as the person), the middle finger, the ring finger, Since three of the little fingers are unsuccessful in collation (determining that they are others), the authentication result is that personal authentication has failed. Further, for example, when comparing the average value of similarity between each finger (in this example, average value = 780) and a threshold value (= 800), since this average value is smaller than the threshold value, matching failure ( It will result in (personal authentication failure).

  On the other hand, in this example in the present embodiment, the vein pattern status determination unit 123 selectively uses (adopts) a finger having a relatively high vein ratio (priority) (value of 0.05 or more). ) On the other hand, a finger with a relatively small vein ratio (value less than 0.05) is determined not to be suitable for vein authentication and is not used. That is, in this example, only three fingers, that is, the thumb, the index finger, and the little finger are to be verified. Therefore, for example, when comparing the average value of similarity between these three fingers (in this example, average value = 1000) and a threshold value (= 800), this average value is larger than the threshold value. As a result, a result of successful verification (successful personal authentication) is obtained. As described above, in the present embodiment, comprehensive judgment is performed in consideration of the magnitude of individual priority (information amount) corresponding to each finger (selectively using a finger having a high priority). Thus, as described above, it is possible to improve the authentication accuracy.

In this example, a case where a finger having a relatively small vein ratio (priority) is not used at the time of collation has been described. However, the present invention is not limited to this. For example, the size of the vein ratio of each finger A method of performing weighting according to the above is also conceivable. That is, for example, the weight of the finger having the largest vein ratio value (thumb in this example) is set to 100, and the other fingers are weighted according to the value of the vein ratio as follows, for example. You may make it utilize in the case of collation, after setting so that it may become small.
・ Weight on index finger: 100 × (0.07 / 0.08) = 87.5
・ Weight at middle finger: 100 × (0.03 / 0.08) = 37.5

  Further, in this example, the case has been described where the vein ratio in the image corresponding to each finger vein pattern Pfv1, Pfv2 is used as an example of priority. However, the present invention is not limited to this, and for example, corresponds to each registered vein pattern Pfv0. The vein ratio in the image to be used may be used as an example of priority. Further, parameters other than the vein ratio (for example, parameters corresponding to the characteristics of the original image such as a difference value between the maximum luminance value and the minimum luminance value in each finger region image If) may be used. .

<2. Modification>
Then, the modification of the said embodiment is demonstrated. In addition, the same code | symbol is attached | subjected to the same thing as the component in embodiment, and description is abbreviate | omitted suitably.

  FIG. 6 is a flowchart showing an example of the personal authentication operation according to the modification. The personal authentication operation of the present modification includes step S17 and step S21 described below between step S12 and step S13 in the personal authentication operation according to the embodiment shown in FIG. This corresponds to a process including step S22 described below instead of S18, and other operations (steps) are the same.

  Specifically, first, in the present modification, immediately after acquiring the palm pattern Pps in step S12, the palm pattern matching unit 134 determines that the palm pattern Pps and the previously registered palm pattern Pps0 are registered. Are collated (step S17 in FIG. 6). That is, in the present modification, unlike the embodiment, after the palm pattern Pps is collated by the palm pattern collating unit 134 (step S17), the finger vein pattern Pfv2 is collated by the vein pattern collating unit 124 (step S17). S16) is performed.

  Here, the authentication unit 14 obtains a difference Dps between the patterns (between the palm pattern Pps and the registered palm pattern Pps0) in Step S17, and this difference Dps is less than a predetermined threshold Dth (Dps <Dth). ) Is determined (step S21). In other words, in this step S21, a preliminary determination is made in the comprehensive determination in the authentication unit 14 described above.

  Here, when it is determined (preliminary determination) that the difference degree Dps is less than the threshold value Dth (Dps <Dth) (step S21: Y), the difference degree Dps is relatively small. It can be seen that it is difficult to cause a problem in the accuracy of finger vein authentication based on the shape pattern Pps. This is because the difference in finger position between finger vein information registration and authentication is relatively small, and the difference in finger vein information due to the difference in finger position is considered to be relatively small. Therefore, in this case, the process proceeds to subsequent steps S13 to S16, S22 (collation in the vein pattern collation unit 124 and comprehensive judgment using the collation result data Cfv (this judgment to be described later)).

  On the other hand, if it is determined (preliminary determination) that the dissimilarity Dps is greater than or equal to the threshold Dth (Dps ≧ Dth) (step S21: N), the dissimilarity Dps is relatively large. It can be seen that problems are likely to occur in the accuracy of finger vein authentication based on the palm pattern Pps. This is because the difference in finger position between finger vein information registration and authentication is relatively large, and the difference in finger vein information due to the difference in finger position is also considered to be relatively large. . Accordingly, in this case, for example, the process returns to the first step S11 without shifting to the subsequent steps S13 to S16, S22. This prompts the user to reacquire the palm image Ip and the like (acquisition of an appropriate palm image Ips and the like having a relatively small difference Dps), which contributes to further improvement in authentication accuracy and convenience. It will be.

  In this modification, after step S16 described above, the authentication unit 14 performs comprehensive determination (main determination) based on the individual matching results (matching result data Cfv) of the plurality of finger vein patterns Pfv2 in step S16. ) To obtain and output a final personal authentication result (authentication result data Bout) (step S22). This completes the series of personal authentication operations shown in FIG.

  As described above, in this modification, unlike the embodiment, the authentication unit 14 uses the verification result data Cps in the palm pattern verification unit 134 when making a comprehensive determination in personal authentication. In addition to making the determination (step S21), this determination is performed using the individual matching result data Cfv of the plurality of finger vein patterns Pfv2 in the vein pattern matching unit 124. That is, the authentication unit 14 makes a comprehensive determination of a two-stage configuration in which the verification result data Cps is used for preliminary preliminary determination and the individual verification result data Cfv is used for final final determination. Yes.

  As a result, in this modified example, it is no longer necessary to always perform finger vein pattern detection and verification processing, regardless of how the palm p is placed, and it is unlikely that problems such as finger vein authentication will occur in preliminary judgment. Only when the determination is made, such finger vein pattern detection and verification processing are performed. Therefore, in this modification, in particular, it is possible to further improve the authentication accuracy, reduce the processing load on the microcomputer or the like, and reduce the power consumption. Further, since the user can replace the palm p without waiting for the finger vein authentication result, it is possible to further improve convenience.

<3. Application example>
Next, an application example (application example to an electronic device) of the biometric authentication device according to the above-described embodiment and modification will be described.

  FIG. 7 is a block diagram illustrating a configuration example of an electronic device (electronic device 2) according to an application example. This electronic device 2 is for causing one or a plurality of biometric authentication devices (in this example, one biometric authentication device 1) described in the above embodiment or modification and a predetermined function as the main body of the electronic device 2 to be exhibited. Various functional units 20 are provided.

  In this example, authentication result data Bout output from the biometric authentication device 1 is supplied to the function unit 20. Then, the function unit 20 performs a predetermined operation using the authentication result data Bout. Specifically, for example, when the authentication result data Bout indicating that the personal authentication is successful is supplied, the function unit 20 performs operations for exhibiting the various functions described above. On the other hand, for example, when the authentication result data Bout indicating that the personal authentication has failed is supplied, the function unit 20 does not execute the operation for exhibiting such various functions.

  Examples of such an electronic device 2 include, for example, various portable information devices (PDA: Personal Digital Assistant) such as smartphones, tablet devices, wearable devices, game devices, television receivers (TV devices), and various home appliances. Examples thereof include terminals in various systems such as an automated teller machine (ATM), a point of sale (POS) terminal, and a medical system.

<4. Other variations>
Although the present invention has been described with the embodiment, the modification, and the application example, the present invention is not limited to the embodiment and the like, and various modifications are possible.

  For example, in the above-described embodiments and the like, the personal authentication method (the comprehensive determination method in the authentication unit 14) has been described with a specific example. However, the personal authentication method (the comprehensive determination method) is not limited thereto. Other methods may be used.

  In addition, the method for acquiring the palm pattern Pps in the palm pattern pattern acquisition unit 131 is not limited to the method described in the above embodiment, and other methods may be used.

  Further, in the above-described embodiment and the like, the case where the light source unit 10 (near infrared light source) that emits the near infrared light Lir is provided has been described as an example. However, the present invention is not limited to this. May not be provided. In other words, in some cases, the image capturing unit 11 may acquire the palm image Ip without using the near infrared light Lir emitted from the light source unit 10.

  The series of processes described in the above embodiments may be performed by hardware (circuit), or may be performed by software (program). When performed by software, the software is composed of a group of programs for causing each function to be executed by a computer. Each program may be used by being incorporated in advance in the computer, for example, or may be used by being installed in the computer from a network or a recording medium.

  DESCRIPTION OF SYMBOLS 1 ... Biometric authentication apparatus, 10 ... Light source part, 11 ... Imaging part, 121 ... Finger area | region extraction part, 122 ... Vein pattern detection part, 123 ... Vein pattern status determination part, 124 ... Vein pattern collation part, 131 ... Palm-shaped pattern Acquisition unit, 131A ... image processing unit, 134 ... palm shape pattern matching unit, 14 ... authentication unit, 15 ... touch sensor, 16 ... liquid crystal panel, 2 ... electronic device, 20 ... functional unit, p ... palm, Lir ... near red Outside light, Ip ... palm image, If ... finger region image, Pfv1, Pfv2 ... finger vein pattern, Pfv0 ... registered vein pattern, Pps ... palm shape pattern, Pps0 ... registered palm shape pattern, Cfv, Cps ... collation result data, Bout ... authentication result data, Dps ... difference, Dth ... threshold.

Claims (13)

An imaging unit that acquires a palm image that is an image including at least a part of a palm of a living body;
A finger region extraction unit that extracts a plurality of finger region images from the palm image acquired by the imaging unit;
A vein pattern detection unit for detecting a plurality of finger vein patterns, respectively, based on the plurality of finger region images extracted by the finger region extraction unit;
A vein pattern matching unit that matches a plurality of finger vein patterns detected by the vein pattern detection unit with a registered vein pattern of a finger registered in advance;
A biometric authentication device comprising: an authentication unit that obtains a final personal authentication result by making a comprehensive determination based on individual verification results of a plurality of finger vein patterns in the vein pattern verification unit. A palm pattern acquisition unit that acquires the palm pattern of the living body;
A palm shape pattern matching unit that matches a palm shape pattern acquired by the palm shape pattern acquisition unit with a registered palm shape pattern registered in advance;
The biometric authentication device according to claim 1, wherein the authentication unit performs the comprehensive determination by using a matching result in the palm pattern matching unit. The biometric authentication device according to claim 2, wherein the vein pattern matching unit performs matching after the palm shape pattern matching unit performs matching. When the authentication unit makes the comprehensive determination,
While making a preliminary judgment using the collation result in the palm pattern matching unit,
The biometric authentication device according to claim 3, wherein the determination is performed using individual matching results of a plurality of finger vein patterns in the vein pattern matching unit. The authentication unit
When the preliminary determination that the difference between the palm pattern acquired by the palm pattern pattern acquisition unit and the registered palm pattern is less than a predetermined threshold is made, the subsequent vein pattern matching unit While shifting to the main judgment using the collation and the collation result,
5. When the preliminary determination that the degree of difference is equal to or greater than the threshold is made, the subsequent verification in the vein pattern verification unit and the main determination using the verification result are not performed. Biometric authentication device. The palm shape pattern acquisition unit acquires the palm pattern by using a detection result of a touch sensor or image processing on a palm image acquired by the imaging unit. The biometric authentication device according to item 1. The biometric authentication device according to any one of claims 1 to 6, wherein the authentication unit performs the comprehensive determination in consideration of individual priority levels in the plurality of finger vein patterns. The vein pattern matching unit selectively uses a finger vein pattern having a relatively high priority among the plurality of finger vein patterns, and performs matching with the registered vein pattern,
The biometric authentication device according to claim 7, wherein the authentication unit performs the comprehensive determination based on a collation result in a finger vein pattern having a relatively high priority. The finger vein pattern having a relatively large amount of information is set so that the priority is relatively large,
The biometric authentication device according to claim 7 or 8, wherein the finger vein pattern having a relatively small amount of information is set so that the priority is relatively small. A light source that emits near-infrared light;
The biometric authentication device according to any one of claims 1 to 9, wherein the imaging unit acquires the palm image using near infrared light emitted from the light source unit. Comprising one or more biometric authentication devices,
The biometric authentication device is:
An imaging unit that acquires a palm image that is an image including at least a part of a palm of a living body;
A finger region extraction unit that extracts a plurality of finger region images from the palm image acquired by the imaging unit;
A vein pattern detection unit for detecting a plurality of finger vein patterns, respectively, based on the plurality of finger region images extracted by the finger region extraction unit;
A vein pattern matching unit that matches a plurality of finger vein patterns detected by the vein pattern detection unit and a registered vein pattern of a finger;
An electronic device comprising: an authentication unit that obtains a final personal authentication result by making a comprehensive determination based on individual verification results of a plurality of finger vein patterns in the vein pattern verification unit. An imaging step of acquiring a palm image that is an image including at least a part of a palm of a living body;
A finger area extraction step for extracting a plurality of finger area images from the palm image acquired in the imaging step;
A vein pattern detection step for detecting each of a plurality of finger vein patterns based on the plurality of finger region images extracted in the finger region extraction step;
A vein pattern matching step for matching a plurality of finger vein patterns detected in the vein pattern detection step with a registered vein pattern of a finger;
A biometric authentication method comprising: an authentication step of obtaining a final personal authentication result by making a comprehensive determination based on individual verification results of a plurality of finger vein patterns in the vein pattern verification step. An imaging step of acquiring a palm image that is an image including at least a part of a palm of a living body;
A finger area extraction step for extracting a plurality of finger area images from the palm image acquired in the imaging step;
A vein pattern detection step for detecting each of a plurality of finger vein patterns based on the plurality of finger region images extracted in the finger region extraction step;
A vein pattern matching step for matching a plurality of finger vein patterns detected in the vein pattern detection step with a registered vein pattern of a finger;
A biometric authentication program that causes a computer to execute an authentication step of obtaining a final personal authentication result by making a comprehensive determination based on individual verification results of a plurality of finger vein patterns in the vein pattern verification step.

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