JP2009165631A - Vein authentication device and vein authentication method - Google Patents

Abstract

A vein authentication device and a vein authentication method are provided that can easily control the amount of light of near-infrared light and ensure the reproducibility of authentication.
A vein authentication device 10 according to the present invention includes a lens array 103 in which a plurality of light receiving lenses that receive transmitted light that has passed through a vein layer are arranged in an array, and an outer periphery of the lens array. Based on the near-infrared light irradiation light source 107 that irradiates the surface with near-infrared light, the wide-angle lens unit 111 that collects the transmitted light received by the lens array, and the transmitted light collected by the wide-angle lens unit The imaging unit 101 includes an imaging element 113 that generates a captured image of the vein layer.
[Selection] Figure 3

Description

  The present invention relates to a vein authentication device and a vein authentication method.

  Biometric personal identification is a very important technology for protecting the rights in the future network society. In particular, in commercial transactions on the Internet, where other people can impersonate themselves and steal money, content, rights, etc. over the Internet, they are attracting attention as a technology that protects areas that cannot be solved by encryption alone. However, fingerprints and irises cannot solve the problem of forgery. In this regard, personal authentication technology using a part that cannot be easily imaged from the outside with a vein pattern is expected as next-generation biometric personal authentication because of its high accuracy of determination, forgery, and impersonation.

  In particular, in an imaging method using a transmission image of a vein, it is difficult to make a planar structure of the device because the position of the light source is greatly limited. Therefore, in order to realize the planar structure of the device, research on contact-type devices has been made (see, for example, Patent Document 1 and Patent Document 2), and devices using, for example, wide-angle lenses have also been proposed. Yes.

JP-A-3-292578 JP 2007-257307 A

  However, the method described in the above-mentioned patent document has a problem that complicated control is required to control the amount of near-infrared light applied to the finger. In addition, in a device using a wide-angle lens, it is difficult to limit the distance between the device and the finger, and it is necessary for the user to securely place the finger at the same distance, so that the reproducibility of authentication cannot be ensured. there were.

  Therefore, the present invention has been made in view of such problems, and the object thereof is new and improved, which is easy to control the amount of near-infrared light and can ensure the reproducibility of authentication. Another object is to provide a vein authentication apparatus and a vein authentication method.

  In order to solve the above problems, according to an aspect of the present invention, a finger surface is irradiated with near infrared light, and a vein layer located inside the finger is imaged by the near infrared light diffused inside the finger. An image capturing unit that performs image correction of an image obtained by capturing the vein layer, a vein pattern extraction unit that extracts a vein pattern from the image-corrected captured image of the vein layer, and the extracted vein pattern An authentication unit that performs an authentication process based on the imaging unit, wherein the imaging unit includes a lens array in which a plurality of light receiving lenses that receive transmitted light that has passed through the vein layer are arranged in an array, and an outer periphery of the lens array A near-infrared light source that irradiates the finger surface with near-infrared light, a wide-angle lens part that condenses the transmitted light received by the lens array, and a light that is collected by the wide-angle lens part Based on the transmitted light before Vein authentication device comprising an image sensor for generating a captured image of the venous layer, is provided.

  The correction unit includes a mirror image correction unit that performs a correction process of a mirror image obtained by the lens array, an aberration correction unit that corrects aberration caused by the wide-angle lens unit, and a luminance distribution correction that corrects the luminance distribution of the captured image. May be further provided.

  The luminance distribution correction unit is configured to obtain a luminance distribution of the captured image so that the luminance distribution of the near-infrared light emitted from the near-infrared light irradiation light source and the imaging luminance distribution of the wide-angle lens are complementary to each other. May be corrected.

  The focal position of the wide-angle lens unit may be set to the imaging position of the lens array.

  The vein authentication device further includes a light shielding wall disposed between the lens array and the near infrared light irradiation light source, and the light shielding wall is emitted from the near infrared light irradiation light source and is applied to the lens array. The near-infrared light that is directly incident may be shielded.

  The focal position of the lens array may be set in the vein layer.

  In order to solve the above-described problem, according to another aspect of the present invention, a vein authentication method for performing near-infrared light irradiation on a finger surface and performing authentication based on a vein pattern of a vein layer located inside the finger A lens array in which a plurality of light-receiving lenses that receive transmitted light that has passed through the vein layer are arranged in an array, and an outer periphery of the lens array, and near-infrared light with respect to the finger surface A near-infrared light irradiating light source that irradiates light, a wide-angle lens portion that condenses the transmitted light received by the lens array, and a captured image of the vein layer based on the transmitted light collected by the wide-angle lens portion An imaging unit including an imaging device that generates an image of the vein layer, a correction process for the vein layer imaging data generated by the imaging unit, and a correction process are performed. From the captured image data, Extracting a vein pattern, a step that is extracted to authenticate the vein pattern, the vein authentication method comprising is provided.

  In order to solve the above problems, according to still another aspect of the present invention, a computer is irradiated with near infrared light on a finger surface, and the near infrared light diffused inside the finger is positioned inside the finger. An imaging unit control function that controls an imaging unit that images the vein layer that performs imaging, a correction function that performs image correction of an image obtained by imaging the vein layer, and a vein that extracts a vein pattern from the captured image of the vein layer that has undergone image correction A program for realizing a pattern extraction function and an authentication function for performing an authentication process based on the extracted vein pattern is provided.

  According to this configuration, the computer program is stored in the storage unit included in the computer, and is read and executed by the CPU included in the computer, thereby causing the computer to function as the vein authentication device. A computer-readable recording medium in which a computer program is recorded can also be provided. The recording medium is, for example, a magnetic disk, an optical disk, a magneto-optical disk, a flash memory, or the like. Further, the above computer program may be distributed via a network, for example, without using a recording medium.

  The vein authentication apparatus according to the present invention can easily control the light amount of near-infrared light, and can ensure the reproducibility of authentication.

  Exemplary embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In addition, in this specification and drawing, about the component which has the substantially same function structure, duplication description is abbreviate | omitted by attaching | subjecting the same code | symbol.

  The inventor of the present application has studied to solve the above-mentioned problems, and has come up with the following knowledge. That is, in vein authentication, a surface sensor such as a CCD (Charge Coupled Devices) or a CMOS (Complementary Metal Oxide Semiconductor) is used as an image sensor, but in such a surface sensor, S caused by thermal noise is used. / N degradation becomes a problem. Therefore, in order to reduce such thermal noise and power consumption and to minimize the influence on the human body, it is necessary to limit the amount of light to be irradiated within a certain range. Also, depending on the person, the surface sensor can easily reach saturation luminance, and it is necessary to control the illumination very precisely.

  In order to realize a contact type device, the sensor size of the surface sensor becomes large, and the cost and the scale of the apparatus become problems. Therefore, a method that can reduce the cost and the scale of the apparatus is required.

  Therefore, as a result of intensive studies to solve these problems, the present inventor has come up with a vein authentication apparatus and a vein authentication method according to the present invention as described below.

(First embodiment)
<About the configuration of the vein authentication device 10>
First, the configuration of the vein authentication apparatus 10 according to the first embodiment of the present invention will be described in detail with reference to FIG. FIG. 1 is a block diagram for explaining a configuration of a vein authentication device 10 according to the present embodiment.

  For example, as illustrated in FIG. 1, the vein authentication device 10 according to the present embodiment includes an imaging unit 101, a correction unit 151, a vein pattern extraction unit 159, an authentication unit 161, a processing unit 167, and a storage unit 169. And mainly.

  The imaging unit 101 captures an image of the body surface (for example, a finger FG) of an individual who desires registration or authentication of a vein pattern, and generates imaging data. The imaging unit 101 according to the present embodiment is a contact-type imaging unit 101 that uses a microlens array (MLA), which is an example of a lens array, and a wide-angle lens. Then, the near-infrared light 12 having a predetermined wavelength is irradiated, and the transmitted light 14 scattered in the finger FG and transmitted through the vein is collected to perform imaging. The imaging unit 101 will be described in detail later again.

  The imaging unit 101 is driven and controlled by an imaging control unit (not shown) including a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like. The unit outputs the obtained imaging data to a correction unit 151 described later. Further, the imaging control unit may record the obtained imaging data in a storage unit 169 described later. In recording in the storage unit 169, the imaging control unit may associate an imaging date, an imaging time, and the like with the generated imaging data. Note that the generated imaging data may be an RGB (Red-Green-Blue) signal, or image data of other colors or gray scales.

(Regarding the configuration of the imaging unit 101)
Here, the configuration of the imaging unit 101 provided in the vein authentication apparatus 10 according to the present embodiment will be described in detail with reference to FIGS. FIG. 2 is an explanatory diagram for explaining the imaging unit 101 according to the present embodiment, and FIG. 3 is a cross-sectional view for explaining the imaging unit 101 according to the present embodiment. FIG. 4 is an explanatory diagram for explaining the imaging unit 101 performed in the vein authentication apparatus 10 according to the present embodiment.

  As shown in FIGS. 2 and 3, for example, the imaging unit 101 according to the present embodiment includes a microlens array 103, a light emitting diode (LED) 107, a light shielding wall 109, a wide-angle lens unit 111, and the like. The image sensor 113 is mainly provided.

  The microlens array 103 is composed of a plurality of microlenses 105, and the microlenses 105 are arranged in a grid pattern on a predetermined substrate as shown in FIGS. For example, as shown in FIG. 3, each microlens 105 guides the transmitted light 14 incident on the microlens 105 from the light incident surface to a wide-angle lens unit 111 described later. Since the microlens array 103 is a lens array having a small curvature of field and no distortion in the depth direction, by using such a microlens array 103, good image data can be obtained. The focal position of each microlens 105 constituting the microlens array 103 is set to be the position of the vein layer where the vein to be imaged by the imaging unit 101 exists.

  It is known that the human skin has a three-layer structure of an epidermis layer, a dermis layer, and a subcutaneous tissue layer, but the above-described vein layer exists in the dermis layer. The dermis layer is a layer present at a thickness of about 2 mm to 3 mm from a position of about 0.1 mm to 0.3 mm with respect to the finger surface. Therefore, by setting the focal position of the microlens 105 at such a position of the dermis layer (for example, a position of about 1.5 mm to 2.0 mm from the finger surface), the transmitted light 14 transmitted through the vein layer is It becomes possible to condense efficiently.

  A plurality of light emitting diodes 107 as an example of a near-infrared light irradiation light source are arranged around the microlens array 103 as shown in FIG. 2, for example, and emit near-infrared light having a predetermined wavelength band with respect to the finger FG. Irradiate. Near-infrared light is highly permeable to body tissues, but is absorbed by hemoglobin in the blood (reduced hemoglobin), so when irradiating near-infrared light on the fingers, palms and back of the hand, The veins distributed inside the fingers, palms and back of the hand appear in the image as shadows. The shadow of the vein that appears in the image is called the vein pattern. In order to image such a vein pattern satisfactorily, the light emitting diode irradiates near infrared light having a wavelength of about 600 nm to 1300 nm, preferably about 700 nm to 900 nm.

  Here, when the wavelength of near-infrared light irradiated by the light emitting diode is less than 600 nm or more than 1300 nm, it is difficult to obtain a good vein pattern because the proportion absorbed by hemoglobin in the blood becomes small. Become. Further, when the wavelength of near-infrared light emitted from the light emitting diode is about 700 nm to 900 nm, the near-infrared light is specifically absorbed by both deoxygenated hemoglobin and oxygenated hemoglobin. A good vein pattern can be obtained.

  Also, instead of using a light emitting diode having the above wavelength band, a combination of a light emitting diode capable of emitting light including the above wavelength band and a filter for optically band limiting the emitted light is used. May be used.

  For example, as shown in FIG. 3, the near-infrared light emitted from the light emitting diode 107 propagates upward toward the surface of the finger FG and directly enters the finger FG as light 12. Here, since the human body is a good scatterer of near-infrared light, the direct light 12 incident on the finger FG propagates while being scattered in all directions. A part of the scattered light is transmitted as back scattered light 13 through the vein layer from the back toward the finger surface, and enters the microlens array 103 as transmitted light 14.

  Further, a light shielding wall 109 is provided between the microlens array 103 and the light emitting diode 107, for example, as shown in FIGS. The light shielding wall 109 shields the direct light 12 so that the direct light 12 emitted from the light emitting diode 107 does not directly enter the microlens 105 of the microlens array 103.

  The wide-angle lens unit 111 is a close-up lens unit provided below the microlens array 103 (on the z-axis negative direction side in FIG. 3), and the transmitted light 14 incident on the microlens 105 on the microlens array 103 will be described later. The light is guided to the image sensor 115. The lens diameter of the wide-angle lens used for the wide-angle lens unit 111 is selected according to the size of the microlens array 103. In addition, the focal position of the wide-angle lens used in the wide-angle lens unit 111 is preferably set to the imaging position of the microlens 105 on the microlens array 103.

  The wide-angle lens is a lens whose effective focal length for forming an image is shorter than the length of the diagonal line of the image plane. By using the wide-angle lens, the length between the microlens array 103 and the wide-angle lens unit 111 is increased. Can be shortened. That is, it is possible to reduce the size of the imaging unit 101 by using the wide-angle lens unit 111 using such a wide-angle lens for condensing the transmitted light 14 that has passed through the microlens array 103. Furthermore, by effectively utilizing the characteristics of the wide-angle lens having a wide angle of view, the light from the microlens array 103 that is larger than the lens diameter of the wide-angle lens can be effectively condensed.

  Note that the wide-angle lens unit 111 may be composed of one wide-angle lens, for example, as shown in FIG. 3, or may be composed of a plurality of lenses including a wide-angle lens.

  The imaging element 113 has an imaging surface in which a plurality of light receiving elements are arranged in a grid, and generates imaging data based on near-infrared light based on the transmitted light 14 imaged by the wide-angle lens unit 111. For example, a CCD image sensor, a C-MOS image sensor, or the like can be used as the image sensor 113 according to the present embodiment. The imaging element 113 outputs the generated imaging data to the correction unit 151 described later. Further, the image sensor 113 may store the generated image data in the storage unit 169 described later.

  A microlens array is a device that is suitable for reading vein patterns that exist several millimeters below the skin, but in order to image the light collected by the microlens array, it is equal to the projected area of the microlens array. Since a large-sized image sensor is required, it has been difficult to put it to practical use. However, in the imaging unit 101 according to the present embodiment, the transmitted light 14 collected by the microlens array 103 is further collected by the wide-angle lens unit 111, and thus an imaging having a sensor size smaller than the projection area of the microlens array. The element can be used effectively.

  Further, for example, as shown in FIG. 3, a condensing lens portion 115 capable of transmitting near-infrared light is disposed between the wide-angle lens portion 111 and the image sensor 113, and the near-infrared light transmitted through the wide-angle lens portion 111. The light may be further condensed. Such a condensing lens unit 115 may be composed of a single lens or a plurality of lenses. The optical lens used for the condensing lens unit 115 can be any lens as long as it can condense near infrared light efficiently.

  When a wide-angle lens is used as a condensing system as in the imaging unit 101 according to the present embodiment, the incident angle of the transmitted light 14 incident on the imaging element 113 increases from the center of the imaging element 113 toward the edge. . Therefore, as shown in FIG. 4A, the sensitivity characteristic at the edge of the image sensor 113 is extremely lower than the sensitivity characteristic at the center of the image sensor 113. Therefore, when a wide-angle lens is used alone, there is a problem that a uniform luminance distribution cannot be obtained in the image sensor 113.

  On the other hand, when the light emitting diode 107 that is a near-infrared light irradiation light source is arranged around the imaging system (microlens array 103) like the imaging unit 101 according to the present embodiment, as shown in FIG. The edge of the image sensor 113 located in the vicinity of the light emitting diode 107 is very bright, while the center of the image sensor 113 is very dark. For this reason, there is a problem that not only an image having a uniform luminance distribution cannot be obtained by the image sensor 113 but also luminance saturation of the image sensor 113 occurs.

  However, the imaging unit 101 according to the present embodiment combines the two configurations of a condensing optical system using a wide-angle lens and a light emitting diode disposed in the immediate vicinity of the imaging system, so that a non-uniform illumination effect by the light emitting diode is obtained. And the non-uniform sensitivity of the wide-angle lens complement each other. As a result, the imaging unit 101 according to the present embodiment can generate imaging data having a nearly uniform luminance distribution as illustrated in FIG. 4C, for example, despite using a wide-angle lens. Is possible.

  Note that, in the imaging unit 101 according to the present embodiment, an optical band suitable for vein imaging with respect to light (transmitted light 14) that has passed through the vein layer that is the object to be measured between the finger FG and the imaging element 113. A filter for limiting may be further provided.

  The configuration of the imaging unit 101 according to the present embodiment has been described above with reference to FIGS. Hereinafter, the configuration of the vein authentication device 10 according to the present embodiment will be described with continued reference to FIG.

  For example, the correction unit 151 includes a CPU, a ROM, a RAM, and the like, and is a processing unit that performs various types of image correction processing on the imaging data captured by the imaging unit 101. The correction unit 151 further includes a mirror image correction unit 153, a luminance distribution correction unit 155, and an aberration correction unit 157.

  Imaging data generated by the imaging element 113 based on the transmitted light 14 collected by one microlens 105 is a mirror image. Therefore, the mirror image correction unit 153 performs inversion correction on each of the plurality of imaging data generated based on the transmitted light 14 collected by each microlens 105 and combines them into one imaging data. The imaging data that has been subjected to the correction processing by the mirror image correction unit 153 is output to the luminance distribution correction unit 155 described later.

  As described above, in the imaging unit 101 according to the present embodiment, the luminance distribution caused by the wide-angle lens unit 111 and the luminance distribution caused by the light-emitting diode 107 are effectively combined, so that the imaging element 113 is substantially uniform. It is possible to obtain a simple luminance distribution. However, the image data generated by the image sensor 113 still has a slight luminance distribution. Therefore, the luminance distribution correction unit 155 corrects the luminance distribution existing in the image data generated by the image sensor 113 within a dynamic range (D range) so as to be uniform. The imaging data on which the brightness correction has been performed is output to an aberration correction unit 157 described later.

  The aberration correction unit 157 corrects the aberration included in the imaging data output from the luminance correction unit 155. Since the imaging unit 101 according to the present embodiment uses a wide-angle lens as a condensing optical system, the generated imaging data receives large aberration distortion such as distortion. Therefore, the aberration correction unit 157 geometrically corrects the tall distortion aberration. The imaging data for which aberration correction has been completed is output to a vein pattern extraction unit 159 described later.

  Note that the correction unit 151 may record the imaging data for which image correction has been completed in the storage unit 169 described later.

  The vein pattern extraction unit 159 includes, for example, a CPU, a ROM, a RAM, and the like. For example, the vein pattern extraction unit 159 has a function of performing preprocessing for vein pattern extraction on near-infrared light imaging data transmitted from the correction unit 151, and veins. It has a function of performing pattern extraction and a function of performing post-processing of vein pattern extraction.

  Here, the pre-processing of the vein pattern extraction described above is, for example, a process of detecting a finger contour from imaged data and identifying where the finger is located in the imaged data, or using the detected finger contour. This includes processing for rotating the imaging data and correcting the angle of the imaging data (angle of the captured image).

  Further, the extraction of the vein pattern is performed by applying a difference filter to the imaging data for which the contour detection and the angle correction have been completed. The difference filter is a filter that outputs a large value as an output value at a portion where the difference between the pixel of interest and the surrounding pixels is large between the pixel of interest and the surrounding pixels. In other words, the difference filter is a filter that emphasizes lines and edges in an image by calculation using a difference between a pixel of interest and a gradation value in the vicinity thereof.

  In general, when filter processing is performed on image data u (x, y) having a lattice point (x, y) on a two-dimensional plane as a variable using a filter h (x, y), the following formula 1 As shown in FIG. 4, image data ν (x, y) is generated. Here, in the following Equation 2, “*” represents a convolution (convolution).

  In the extraction of the vein pattern according to the present embodiment, a differential filter such as a primary spatial differential filter or a secondary spatial differential filter may be used as the differential filter. The primary spatial differential filter is a filter that calculates a difference between gradation values of adjacent pixels in the horizontal direction and the vertical direction for the pixel of interest, and the secondary spatial differential filter is the pixel of interest. Is a filter that extracts a portion where the amount of change in the difference in gradation value is large.

  As the second-order spatial differential filter, for example, the following Log (Laplacian of Gaussian) filter can be used. The Log filter (Equation 3) is expressed by the second derivative of a Gaussian filter (Equation 2) that is a smoothing filter using a Gaussian function. Here, in Expression 2 below, σ represents a standard deviation of a Gaussian function, and is a variable representing the degree of smoothing of the Gaussian filter. In addition, σ in Equation 3 below is a parameter that represents the standard deviation of the Gaussian function as in Equation 2, and by changing the value of σ, the output value when the Log filter processing is performed can be changed. it can.

  Further, the post-processing of the vein pattern extraction includes, for example, threshold processing, binarization processing, thinning processing, and the like performed on the image data after application of the difference filter. Through such post-processing, it is possible to extract a skeleton of a vein pattern.

  The vein pattern extraction unit 159 transmits the vein pattern and skeleton extracted in this way to the authentication unit 161 described later. The vein pattern extraction unit 159 may store the extracted vein pattern and skeleton in the storage unit 169 described later. In addition, the vein pattern extraction unit 159 may store the parameters generated when performing the above-described processes, the progress of the process, and the like in the storage unit 169.

  The authentication unit 161 includes, for example, a CPU, a ROM, a RAM, and the like, and registers the vein pattern generated by the vein pattern extraction unit 159 as a template, or the vein pattern generated by the vein pattern extraction unit 159 has already been registered. The vein pattern is verified against the template in use. For example, the authentication unit 161 further includes a vein pattern registration unit 163 and a vein pattern authentication unit 165.

  The vein pattern registration unit 163 registers the vein pattern generated by the vein pattern extraction unit 159 as a template in the storage unit 169 described later. In addition, when registering a registered vein pattern, not only the vein pattern but also other data (for example, fingerprint data, face image data, iris data, voiceprint data, etc.) for specifying an individual having the vein pattern is associated with the vein pattern. You may remember. The registered vein pattern registered as a template may have header information in accordance with a standard such as CBEFF (Common Biometric Exchange File Format).

  The vein pattern authentication unit 165 authenticates the generated vein pattern based on the vein pattern generated by the vein pattern extraction unit 159 and the vein pattern template already recorded. The vein pattern authentication unit 165 requests the storage unit 169 to be described later to disclose a registered vein pattern, and compares the acquired registered vein pattern with the vein pattern transmitted from the vein pattern extraction unit 159. The comparison between the registered vein pattern and the transmitted vein pattern can be performed, for example, by calculating a correlation coefficient shown below and based on the calculated correlation coefficient. The vein pattern authentication unit 165 authenticates the transmitted vein pattern when the registered vein pattern and the transmitted vein pattern are similar as a result of comparison, and does not authenticate when they are not similar.

The correlation coefficient is defined by Equation 4 below, and is a statistical index indicating the similarity between two data x = {x _i }, y = {y _i }, and is from −1 to 1 Take real values up to. When the correlation coefficient indicates a value close to 1, it indicates that the two data are similar. When the correlation coefficient indicates a value close to 0, the two data indicate that they are not similar. Show. Further, when the correlation coefficient shows a value close to -1, the case where the signs of the two data are inverted is shown.

  The vein pattern authentication unit 165 may record the authentication result in the storage unit 169 as an authentication history in association with the authentication time. By generating such an authentication history, it becomes possible to know who requested the vein pattern authentication and who used the information processing apparatus 10.

  The processing unit 167 includes, for example, a CPU, a ROM, a RAM, and the like, and executes predetermined processing according to the vein pattern authentication result output from the authentication unit 161. In other words, when the processing unit 167 receives a notification from the authentication unit 161 that the vein pattern authentication has been successful, the processing unit 167 releases the restriction on the predetermined process that is restricted to be executed, and executes the process.

  The storage unit 169 stores a registered vein pattern requested for registration from the vein pattern registration unit 163 and other data associated with the registered vein pattern. In addition to these data, it is also possible to store imaging data generated by the imaging unit 101, vein patterns extracted by the vein pattern extraction unit 159, and the like. In addition to these data, the vein authentication apparatus 10 can appropriately store various parameters, the progress of processing, etc. that need to be saved when performing some processing, or various databases. Is possible. The storage unit 169 can be freely read and written by the imaging unit 101, the correction unit 151, the vein pattern extraction unit 159, the authentication unit 161, the processing unit 167, and the like.

  Heretofore, an example of the function of the vein authentication device 10 according to the present embodiment has been shown. Each component described above may be configured using a general-purpose member or circuit, or may be configured by hardware specialized for the function of each component. In addition, the CPU or the like may perform all functions of each component. Therefore, it is possible to appropriately change the configuration to be used according to the technical level at the time of carrying out the present embodiment.

  The vein authentication device 10 according to the present embodiment includes, for example, an information processing device such as a computer or a server, a mobile terminal such as a mobile phone or PHS, a personal digital assistant (PDA), an automatic teller machine (ATM), an entrance / exit You may mount in various apparatuses, such as a management apparatus, a game device, and the controller of a game device.

  In the above description, the registered vein pattern registered as a template has been described as being recorded in the vein authentication apparatus 10. However, the registered vein pattern can be a DVD medium, an HD-DVD medium, a Blu-ray medium, The information may be recorded on a recording medium such as a CompactFlash (registered trademark), a memory stick, or an SD memory card, or an IC card or an electronic device mounted with a non-contact type IC chip. It may be recorded on a server connected via a network.

<About the vein authentication method according to this embodiment>
Next, the vein authentication method according to the present embodiment will be described in detail with reference to FIG. FIG. 5 is a flowchart for explaining the vein authentication method according to the present embodiment.

  First, the imaging unit 101 of the vein authentication device 10 according to the present embodiment irradiates a finger placed on the imaging unit 101 with near infrared light, and images a vein layer located inside the finger (step). S101). The imaging data generated by the imaging unit 101 is output to the correction unit 151 of the vein authentication device 10 according to the present embodiment.

  Next, the mirror image correction unit 151 performs inversion correction for correcting the mirror image on the imaging data output from the imaging unit 101, and combines the imaging data into one piece of imaging data (step) S103). When the mirror image correction process is completed, the mirror image correction unit 151 outputs the imaging data to the luminance distribution correction unit 153.

  Subsequently, the luminance distribution correction unit 153 corrects the luminance distribution of the imaging data output from the mirror image correction unit 151 so that the imaging data has a uniform luminance distribution (step S105). The luminance distribution correction unit 153 outputs the imaging data to the aberration correction unit 155 when the luminance distribution correction processing ends.

  Next, the aberration correction unit 155 performs processing for removing various aberrations caused by the wide-angle lens used in the imaging unit 101 from the imaging data (step S107). The imaging data from which the aberration is removed is output to the vein pattern extraction unit 159.

  Subsequently, the vein pattern extraction unit 159 extracts a vein pattern from the imaging data transmitted from the correction unit 151 (step S109). When the extraction of the vein pattern ends, the vein pattern extraction unit 159 outputs the extracted vein pattern to the authentication unit 161.

  Next, the authentication unit 161 performs vein pattern authentication processing based on the vein pattern output from the vein pattern extraction unit 159 (step S111). Here, when the user using the vein authentication device 10 desires to register a vein pattern, the vein pattern registration unit 163 of the authentication unit 161 outputs the vein pattern output from the vein pattern extraction unit 159. Is registered in the storage unit 169 as a registered vein pattern. When the user using the vein authentication device 10 desires vein pattern authentication, the vein pattern authentication unit 165 of the authentication unit 161 includes a registered vein pattern and a vein pattern already registered. The vein pattern output from the extraction unit 159 is compared, and if the vein pattern output from the vein pattern extraction unit 159 is a registered vein pattern, the processing unit 167 is notified that the authentication is successful. If the vein pattern output from the vein pattern extraction unit 159 does not match the registered vein pattern, the authentication unit 161 notifies the processing unit 167 that the authentication has failed.

  Subsequently, the processing unit 167 performs predetermined processing according to the authentication result notified from the authentication unit 161 (step S113). In other words, when receiving a notification that the authentication is successful from the authentication unit 161, the processing unit 167 removes the restriction on a predetermined process whose execution is restricted, and executes the process. In addition, when receiving a notification that the authentication has failed from the authentication unit 161, the processing unit 167 ends the processing.

  Although the vein authentication method according to the present embodiment has been described above, the above-described authentication method does not necessarily have to be performed in time series according to the described order. For example, in the above description, the luminance distribution correction is first performed after the mirror image correction processing, and then the aberration correction processing is performed. However, the aberration correction processing is first performed after the mirror image correction processing, and then the luminance distribution correction is performed. Good.

<Hardware Configuration of Vein Authentication Device 10>
Next, the hardware configuration of the vein authentication device 10 according to the present embodiment will be described in detail with reference to FIG. FIG. 6 is a block diagram for explaining a hardware configuration of the vein authentication device 10 according to the present embodiment.

  The vein authentication device 10 mainly includes a CPU 901, a ROM 903, a RAM 905, a host bus 907, a bridge 909, an external bus 911, an interface 913, an input device 915, an output device 917, and a storage device 919. , A drive 921, a connection port 923, and a communication device 925.

  The CPU 901 functions as an arithmetic processing unit and a control unit, and controls all or part of the operation in the vein authentication device 10 according to various programs recorded in the ROM 903, the RAM 905, the storage device 919, or the removable recording medium 927. The ROM 903 stores programs used by the CPU 901, calculation parameters, and the like. The RAM 905 primarily stores programs used in the execution of the CPU 901, parameters that change as appropriate during the execution, and the like. These are connected to each other by a host bus 907 constituted by an internal bus such as a CPU bus.

  The host bus 907 is connected to an external bus 911 such as a PCI (Peripheral Component Interconnect / Interface) bus via a bridge 909.

  The input device 915 is an operation unit operated by the user, such as a mouse, a keyboard, a touch panel, a button, a switch, and a lever. Further, the input device 915 may be, for example, remote control means (so-called remote control) using infrared rays or other radio waves, or an external connection device such as a mobile phone or a PDA corresponding to the operation of the vein authentication device 10. 929 may be used. Furthermore, the input device 915 includes an input control circuit that generates an input signal based on information input by a user using the above-described operation means and outputs the input signal to the CPU 901, for example. The user of the vein authentication device 10 can input various data and instruct a processing operation to the vein authentication device 10 by operating the input device 915.

  The output device 917 is, for example, a display device such as a CRT display device, a liquid crystal display device, a plasma display device, an EL display device and a lamp, a sound output device such as a speaker and headphones, a printer device, a mobile phone, a facsimile, etc. It is comprised with the apparatus which can notify the information which carried out visually or audibly to a user. For example, the output device 917 outputs results obtained by various processes performed by the vein authentication device 10. Specifically, the display device displays the results obtained by the various processes performed by the vein authentication device 10 as text or images. On the other hand, the audio output device converts an audio signal composed of reproduced audio data, acoustic data, and the like into an analog signal and outputs the analog signal.

  The storage device 919 is a data storage device configured as an example of a storage unit of the vein authentication device 10. For example, a magnetic storage device such as an HDD (Hard Disk Drive), a semiconductor storage device, an optical storage device, or It is composed of a magneto-optical storage device or the like. The storage device 919 stores programs executed by the CPU 901 and various data, and acoustic signal data and image signal data acquired from the outside.

  The drive 921 is a recording medium reader / writer, and is built in or externally attached to the vein authentication apparatus 10. The drive 921 reads information recorded on a removable recording medium 927 such as a mounted magnetic disk, optical disk, magneto-optical disk, or semiconductor memory, and outputs the information to the RAM 905. In addition, the drive 921 can write a record on a removable recording medium 927 such as a magnetic disk, an optical disk, a magneto-optical disk, or a semiconductor memory. The removable recording medium 927 is, for example, a DVD medium, an HD-DVD medium, a Blu-ray medium, a compact flash (registered trademark) (CompactFlash: CF), a memory stick, or an SD memory card (Secure Digital memory card). Further, the removable recording medium 927 may be, for example, an IC card (Integrated Circuit card) on which a non-contact IC chip is mounted, an electronic device, or the like.

  The connection port 923 includes, for example, a USB (Universal Serial Bus) port, i. A port for directly connecting a device such as an IEEE 1394 port such as Link, a SCSI (Small Computer System Interface) port, an RS-232C port, an optical audio terminal, an HDMI (High-Definition Multimedia Interface) port, etc. to the vein authentication device 10 is there. By connecting the external connection device 929 to the connection port 923, the vein authentication device 10 directly acquires the audio signal data and the image signal data from the external connection device 929, or acquires the audio signal data and the image signal from the external connection device 929. Or provide data.

  The communication device 925 is a communication interface including a communication device for connecting to the communication network 931, for example. The communication device 925 is, for example, a wired or wireless LAN (Local Area Network), Bluetooth, or WUSB (Wireless USB) communication card, an optical communication router, an ADSL (Asymmetric Digital Subscriber Line) router, or various types. It is a modem for communication. The communication device 925 can transmit and receive an acoustic signal and the like with the Internet and other communication devices, for example. The communication network 931 connected to the communication device 925 is configured by a wired or wireless network, and may be, for example, the Internet, a home LAN, infrared communication, radio wave communication, satellite communication, or the like. .

  Heretofore, an example of the hardware configuration capable of realizing the function of the vein authentication device 10 according to each embodiment of the present invention has been shown. Each component described above may be configured using a general-purpose member, or may be configured by hardware specialized for the function of each component. Therefore, it is possible to change the hardware configuration to be used as appropriate according to the technical level at the time of carrying out this embodiment.

  As described above, in the vein authentication device 10 and the vein authentication method according to the present embodiment, finger vein authentication can be implemented in a planar structure by using reflected and scattered light in the planar structure, and as a result, It is possible to realize a contact-type vein authentication device that can easily control the amount of near-infrared light and can ensure the reproducibility of authentication.

  In addition, by using a wide-angle lens as the condensing optical system, it is possible to reduce the size of the image pickup device and to reduce the size of the image pickup device in spite of the method using the image pickup device using the microlens array. Can be miniaturized.

  Furthermore, by arranging the near-infrared light irradiation light source around the microlens array, the near-infrared light irradiation light source and the imaging system including the microlens array can be integrated.

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to this example. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Understood.

It is a block diagram for demonstrating the structure of the vein authentication apparatus which concerns on the 1st Embodiment of this invention. It is explanatory drawing for demonstrating the imaging part which concerns on the same embodiment. It is sectional drawing for demonstrating the imaging part which concerns on the same embodiment. It is explanatory drawing for demonstrating the imaging part performed with the vein authentication apparatus which concerns on the same embodiment. It is a flowchart for demonstrating the vein authentication method which concerns on the embodiment. It is a block diagram for demonstrating the hardware constitutions of the vein authentication apparatus which concerns on the embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Vein authentication apparatus 12 Direct light 13 Back scattered light 14 Transmitted light 101 Imaging part 103 Micro lens array 105 Micro lens 107 Light emitting diode 109 Light-shielding wall 111 Wide angle lens part 113 Imaging element 115 Condensing lens part 151 Correction | amendment part 153 Mirror image correction | amendment part 155 Brightness distribution correction unit 157 Aberration correction unit 159 Vein pattern extraction unit 161 Authentication unit 163 Vein pattern registration unit 165 Vein pattern authentication unit 167 Processing unit 169 Storage unit FG Finger

Claims (7)

An imaging unit that irradiates a finger surface with near infrared light and images a vein layer located inside the finger by the near infrared light diffused inside the finger;
A correction unit that performs image correction of an image obtained by imaging the vein layer;
A vein pattern extraction unit that extracts a vein pattern from the image-corrected captured image of the vein layer;
An authentication unit that performs an authentication process based on the extracted vein pattern;
With
The imaging unit
A lens array in which a plurality of light-receiving lenses that receive transmitted light that has passed through the vein layer are arranged in an array;
A near-infrared light irradiation light source that is disposed on the outer periphery of the lens array and irradiates the finger surface with near-infrared light;
A wide-angle lens unit that collects the transmitted light received by the lens array;
An imaging element that generates a captured image of the vein layer based on the transmitted light collected by the wide-angle lens unit;
A vein authentication device comprising: The correction unit is
A mirror image correction unit that performs correction processing of a mirror image obtained by the lens array;
An aberration correction unit that corrects aberration caused by the wide-angle lens unit;
A luminance distribution correction unit for correcting the luminance distribution of the captured image;
The vein authentication apparatus according to claim 1, further comprising: The luminance distribution correction unit
Correcting the luminance distribution of the captured image so that the luminance distribution of the near-infrared light emitted from the near-infrared light irradiation light source and the imaging luminance distribution of the wide-angle lens are complementary to each other. The vein authentication device according to claim 2. The vein authentication apparatus according to claim 1, wherein a focal position of the wide-angle lens unit is set to an imaging position of the lens array. The vein authentication apparatus further includes a light shielding wall disposed between the lens array and the near-infrared light irradiation light source,
The vein authentication apparatus according to claim 1, wherein the light shielding wall shields the near infrared light emitted from the near infrared light irradiation light source and directly incident on the lens array. The vein authentication apparatus according to claim 1, wherein a focal position of the lens array is set in the vein layer. A vein authentication method that irradiates near-infrared light on a finger surface and performs authentication based on a vein pattern of a vein layer located inside the finger,
A lens array in which a plurality of light receiving lenses that receive transmitted light that has passed through the vein layer are arranged in an array, and an outer periphery of the lens array, and a near infrared light that irradiates the finger surface with near infrared light An infrared light irradiation light source, a wide-angle lens unit that collects the transmitted light received by the lens array, and an imaging that generates a captured image of the vein layer based on the transmitted light collected by the wide-angle lens unit Imaging the vein layer by an imaging unit comprising an element;
Correcting the vein layer imaging data generated by the imaging unit; and
Extracting the vein pattern from the imaging data subjected to the correction process;
Authenticating the extracted vein pattern;
The vein authentication method characterized by including.

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