JP2018205785A - Personal authentication device - Google Patents

Abstract

To provide a personal authentication device in which reading means of a finger vein pattern is thinned.SOLUTION: A personal identification device of the present invention comprises reading means for reading information including a vein pattern of a finger and authentication means having a database in which data for authentication of finger vein pattern is recorded in advance. The reading means comprises a pair of light source unit and an imaging unit arranged in parallel in the longitudinal direction of an abutting finger and the imaging unit has a close-up type wide angle lens, a lens holder, and imaging elements. The lens holder has a shape that opens toward the imaging direction and has an inner surface enlarging toward the imaging direction, and holds the close-up wide angle lens at the root portion where the inner dimension is short.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a personal authentication device that performs identity verification based on a finger vein pattern, and more particularly, to a personal authentication device in which a reading unit that reads a finger vein pattern is thinned.

  The vein pattern, which is biometric information, is in-vivo information and is difficult to forge. Further, since the vein pattern is not determined by human genetic information (DNA base sequence), even if identical twins having the same genetic information have different vein patterns, they can be identified. Therefore, the personal authentication based on the vein pattern has high identification accuracy.

  Outline the mechanism of personal authentication based on finger vein pattern. When a (near) infrared ray is incident on a finger, the (near) infrared ray that passes through the inside of the finger is easily absorbed by hemoglobin flowing in the veins of the finger. The finger vein pattern appears as a black shadow. Therefore, a specific person's vein pattern is recorded in the database in advance as authentication data, and when performing authentication, the specific person's vein pattern obtained from the reading means of the personal authentication device and the recorded vein pattern (for authentication) Data) can be used for personal authentication.

  The specific structural aspect of a personal authentication apparatus is illustrated. A light source such as an LED (: light emitting diode) is arranged on the inner surface of a case where a specific person inserts a finger, and a CCD (: charge-coupled device) image sensor is arranged on the inner surface facing the LED. . As the LED, a (near) infrared LED is used, and in addition to a CCD image sensor, a two-dimensional photosensor such as a complementary metal oxide semiconductor (CMOS) image sensor can be used. The light emitted from the LED is transmitted through the finger, the transmitted light image of the vein pattern is captured by a CCD image sensor, converted into a digital signal, and if there is authentication data corresponding to the database, the person is identified as the person. .

  FIG. 4 is a schematic view showing a conventional contact-type vein pattern reading means (see Patent Document 1). As shown in FIG. 4, when a specific person abuts the finger 41 on the surface of the finger rest 45, the light source 43 irradiates the finger 41 with infrared rays, and the infrared rays pass through the inside of the fingers 41, To reach. Among the infrared rays that reach the opening 40, the infrared rays that are emitted to the outside of the finger 41 pass through the opening 40, the acrylic plate 44, and the infrared transmission filter 47, reach the imaging device 49, and image the reaching infrared rays. The acrylic plate 44 is transparent to infrared rays, and prevents a finger or a foreign object from entering the reading unit 42. In the reading means 42, the opening 40 is described as being able to reduce the size of the reading means 42 by making the distance in the longitudinal direction of the finger 41 shorter than the length of the finger 41. However, as shown in FIG. 4, the reading means 42 has a long and thick distance L from the surface with which the finger 41 abuts to the imaging device 49, so that the mounting position of the reading means is limited and attachment processing is not easy. .

JP 2008-5854 A

  An object of the present invention is to provide a personal authentication device in which a finger vein pattern reading means is thinned. Another object of the present invention is to provide a personal authentication device including a reading unit that can collect a wide range of vein pattern information with a single lens.

  The present invention relates to a personal authentication device that reads a vein pattern of a finger abutting and identifies the person based on the vein pattern, and includes a reading unit that reads information including the finger vein pattern and authentication data for the finger vein pattern. Authentication means having a pre-recorded database. The reading unit includes a pair of light source units and an imaging unit that are arranged in parallel in the longitudinal direction of the abutting finger. The imaging unit includes a close-up wide-angle lens, a lens holder, and an imaging device. The lens holder has a shape that opens toward the photographing direction, has an inner surface that expands toward the photographing direction, and holds the close-up type wide-angle lens at a root portion having a short inner dimension. In addition, the imaging unit images light that has entered the finger from the light source unit, passes through the finger, and passes through the close-up type wide-angle lens.

  On the other hand, the authentication unit is configured to be able to receive imaging information from the imaging unit. When receiving imaging information from the imaging unit, the authentication unit extracts a vein pattern from the imaging information, and authentication data corresponding to the extracted vein pattern If is in the database, confirm that you are the person. Since the reading means constituting the personal authentication apparatus of the present invention is provided with a close-up type wide-angle lens, a wide range of information can be collected by one lens, and the reading means can be made thin.

  The close-up type wide-angle lens preferably has an angle of view of 100 ° to 150 °, and the focal length is preferably 0.5 mm to 1.5 mm. The reading means preferably has a thinned aspect in which the distance from the contact surface of the finger to the imaging element is 8.5 mm or less when the finger is in contact, and the light source has an optical axis of light to be irradiated, A structure that is inclined outward as viewed from the imaging unit in parallel with the light source unit is preferable for obtaining a vein pattern with good contrast. In the reading unit, it is preferable that the plurality of light source units are arranged with the imaging unit interposed therebetween in that the light emitted from the light source unit is uniformly filled inside the finger.

  The reading unit includes a concave finger placement guide, and when the light source unit and the imaging unit are arranged on the finger placement guide, the accuracy of personal authentication can be improved. Further, an aspect in which the reading unit is arranged for each finger so that the vein pattern can be read from a plurality of fingers is also preferable in terms of improving the accuracy of personal authentication. On the other hand, when the reading unit is provided with a light-shielding partition wall between the light source unit and the imaging unit, a high-contrast vein pattern can be obtained. The lens holder preferably has a shape in which the inner surface expands in a trumpet shape in the shooting direction. Moreover, the aspect in which the opening end of the lens holder protrudes from the top of the light source portion in the imaging direction by 0.3 mm to 1.5 mm and the aspect in which the light-absorbing light-shielding material is provided inside the opening end of the lens holder are both provided. It is preferable for increasing the contrast of the vein pattern and performing highly accurate personal authentication. The reading means can be arranged on a door lever, a steering wheel of a vehicle, a mobile phone or a case of a mobile phone.

  Since the reading means constituting the personal authentication device of the present invention is thin, there are few restrictions on the installation location, and the installation work is easy. Further, since a wide range of vein pattern information can be collected by one lens, a finger vein pattern can be obtained without arranging many lenses and many image sensors as in the prior art, and it is inexpensive. A personal authentication device can be provided.

It is a conceptual diagram which shows the function of the personal authentication apparatus of this invention. It is explanatory drawing which illustrates the hardware constitutions of the personal authentication apparatus of this invention. It is a flowchart which implements the personal authentication apparatus of this invention. It is a schematic diagram which shows the conventional contact type vein pattern reading means. It is an example of the database which comprises the authentication means in the personal authentication apparatus of this invention. It is a conceptual diagram which shows the structure of the reading means which comprises the personal authentication apparatus of this invention (built-in type reading means). It is a conceptual diagram which shows the structure of the reading means which comprises the personal authentication apparatus of this invention (external type reading means). It is a conceptual diagram which shows the structure of the reading means which comprises the personal authentication apparatus of this invention (the light source part which inclines). It is a conceptual diagram which shows the structure of the reading means which comprises the personal authentication apparatus of this invention (finger placement guide). It is explanatory drawing which shows the example which attached the reading means which comprises the personal authentication apparatus of this invention to the door lever. It is explanatory drawing which shows the example which attached the reading means which comprises the personal authentication apparatus of this invention to the case of a mobile telephone. It is a conceptual diagram which shows the structure of the reading means which comprises the personal authentication apparatus of this invention.

  The personal authentication device according to the present invention reads a vein pattern of a finger of a specific person in contact with the personal authentication device, and performs personal authentication based on the vein pattern. Personal authentication is a process of confirming and certifying that a specific person is really the person. The personal authentication device of the present invention includes a reading unit and an authentication unit, and the reading unit reads information including a finger vein pattern. Specifically, an image of a finger that is in contact with the reading unit is taken. The authentication means has a database in which authentication data for finger vein patterns is recorded in advance. The authentication unit extracts a vein pattern from the imaging information acquired by the reading unit, and performs personal authentication based on the extracted vein pattern and authentication data.

  FIG. 1 is a conceptual diagram showing the function of the personal authentication device of the present invention. In FIG. 1, a reading unit that is an input unit 111 acquires imaging information of a finger including a vein pattern, and inputs the imaging information. Further, the input means 111 inputs the authentication data for the static membrane pattern using a CD-ROM or the like. The control unit 112 records the authentication data input by the input unit 111 in the storage unit 114. The display unit 113 displays the recorded information and the like on the display as necessary. On the other hand, the output means 115 transmits the result of personal authentication to the outside of the personal authentication device, for example.

  FIG. 2 is an explanatory diagram illustrating the hardware configuration of the personal authentication device of the present invention. In FIG. 2, a CPU 122 is a control unit, and an input circuit 121 and a reading unit 130 are input units. The database 124 is a storage unit, and records authentication data 134 necessary for performing personal authentication based on a vein pattern, an operating system (OS) 131, and the like. As shown in FIG. 2, a CPU 122, an input circuit 121, a display 123, a reading unit 130, an output circuit 125, a database 124, and a memory 126 are connected to each other, and these hardware cooperate to perform personal authentication.

  The CPU 122 executes personal authentication based on a program recorded in the memory 126. In the personal authentication device shown in FIG. 2, when the reading unit 130 acquires and inputs imaging information including a vein pattern of a specific person, the CPU 122 records the input imaging information in the memory 126. Next, the CPU 122 extracts a vein pattern from the image information recorded in the memory 126 and records the extracted vein pattern in the memory 126. In addition, the CPU 122 acquires the authentication data 134 from the database 124 and records the authentication data 134 in the memory 126. Thereafter, the CPU 122 compares the vein pattern extracted from the image information with the authentication data, and authenticates the specific person with the corresponding person when there is corresponding information.

  FIG. 6 is a conceptual diagram showing the structure of the reading means constituting the personal authentication device of the present invention. FIG. 6A shows a structure when the reading unit 1 is cut in the longitudinal direction of the finger 9, and shows a state immediately before the abdomen of the finger 9 contacts the reading unit 1. The reading unit 1 includes a set of light source unit 2 and imaging unit 3 arranged in parallel in the longitudinal direction of the finger 9 that abuts. The embodiment illustrated in FIG. 6 is a built-in reading unit in which the light source unit 2 and the imaging unit 3 are arranged inside a member to which the reading unit 1 is attached.

  In the example shown in FIG. 6A, the reading unit 1 arranges two light source units 2 with the imaging unit 3 interposed therebetween. Even if only one of the light source units 2 is arranged, personal authentication can be performed effectively. However, as shown in FIG. 2 is preferable in that the near-infrared light irradiated from 2 can be uniformly filled in the finger 9. An aspect in which a plurality of light sources are provided in a direction orthogonal to the longitudinal direction of the finger 9 is also preferable in that the near infrared light can be uniformly filled in the finger 9. Since hemoglobin constituting red blood cells flowing in the finger vein specifically absorbs near-infrared light, the light source unit is composed of a light source that emits light including near-infrared light. Near-infrared light is an electromagnetic wave having a wavelength of 0.7 to 2.5 μm, and is the same as the electromagnetic wave employed in an infrared camera, a remote controller of household electrical appliances, and the like. As such a light source, an LED is preferable in terms of energy saving and long life.

  The reading unit 1 illustrated in FIG. 6A includes a light blocking partition 4 between the light source unit 2 and the imaging unit 3. When the opaque partition wall 4 is disposed, it is possible to prevent a reflected wave transmitted through the surface of the finger 9 from entering the imaging unit 3 among the light emitted from the light source unit 2 and to increase the contrast of the vein pattern in the captured image. preferable. As shown in FIG. 6 (a), the partition 4 is preferably configured such that the top reaches the surface of the reading means in that it effectively blocks the reflected wave. The reading unit 1 illustrated in FIG. 6A includes a transparent protective plate 5. It is preferable to dispose the protective plate 5 in that foreign matter such as dust can be prevented from entering the reading device 1 and the light source unit 2 and the imaging unit 3 can be protected. As the protective plate, for example, a transparent acrylic plate can be used.

  FIGS. 6B and 6C show the structure of the imaging unit 3, FIG. 6B is a front view, and FIG. 6C is a plan view. The imaging unit 3 includes a close-up type wide-angle lens 3a, a lens holder 3b that holds the close-up type wide-angle lens 3a, and an imaging element 3c. After the abdomen of the finger 9 comes into contact with the reading unit 1, the imaging element 3c picks up the light that has entered the finger 9 from the light source unit 2 and passes through the finger and passes through the close-up type wide-angle lens 3a. To do. A mode in which the personal authentication device is started by a contact sensor, a temperature sensor or the like when the finger 9 of the specific person contacts the reading unit 1 is preferable in that the personal authentication can be automated.

  In the close-up type wide-angle lens 3a in FIG. 6B, the angle of view is preferably 100 ° or more, more preferably 110 ° or more, and more than 120 ° in that one lens can acquire image information including a wide range of vein patterns. Is particularly preferred. On the other hand, when the angle of view of the lens increases, the peripheral portion of the image is deformed so as to flow outward, and the peripheral portion tends to become darker. Therefore, in order to obtain a highly accurate vein pattern, the angle of view of the close-up type wide-angle lens 3a is preferably 150 ° or less, more preferably 145 ° or less, and particularly preferably 140 ° or less. The imaging unit constituting the personal authentication apparatus of the present invention can obtain image information including a wide range of vein patterns with one lens by using a wide-angle lens. Therefore, a finger vein pattern can be obtained without arranging many lenses and many image sensors as in the prior art, and an inexpensive personal authentication device can be provided.

  The personal authentication device of the present invention performs personal authentication based on the finger vein pattern, but finger veins are often distributed in the dermis layer, and the dermis layer is distributed in a large amount from 1.5 mm to 3.0 mm from the finger surface. The depth of subject (the distance from the surface of the finger to the subject) is preferably set to 1.5 mm to 3.0 mm. In the embodiment illustrated in FIG. 6, since the reading unit 1 includes the protection plate 5, the distance L <b> 1 from the surface of the protection plate 5 to the close-up wide-angle lens 3 a, i.e., the finger 9, as illustrated in FIG. The distance L1 from the surface of the finger 9 to the close-up type wide-angle lens 3a when contacting the protective plate 5 is preferably 7 mm or less, and more preferably 6 mm or less in terms of reducing the thickness of the reading unit 1. In such an embodiment, the subject distance of the close-up type wide-angle lens 3a (the distance from the close-up type wide-angle lens to the vein pattern as the subject) is preferably 10 mm or less, more preferably 9.0 mm or less, and particularly preferably 7.5 mm. It is as follows.

  The close-up type wide-angle lens 3a is not necessarily a single lens, and for example, three or four combination lenses can be used. The focal length of the close-up wide-angle lens is preferably 1.5 mm or less, more preferably 1.2 mm or less, and particularly preferably 1.0 mm or less from the viewpoint of providing a thin reading means. On the other hand, the focal length of the close-up type wide-angle lens 3a is preferably 0.5 mm or more, and more preferably 0.7 mm or more in terms of reducing distortion of the captured image. In this manner, as shown in FIG. 6B, when the distance L from the surface of the protective plate 5 to the image sensor 3c, that is, when the finger 9 is in contact, the distance from the contact surface of the finger 9 to the image sensor 3c is obtained. The thin reading means 1 having a distance L of preferably 8.5 mm or less, more preferably 8.0 mm or less, and particularly preferably 7.0 mm or less can be provided. A lens diameter of, for example, 4 mm to 5 mm can be preferably used.

  The lens holder 3b has a shape that opens toward the shooting direction, has an inner surface that expands toward the shooting direction, and holds the close-up type wide-angle lens 3a at a root portion with a short inner dimension. FIG. 6B illustrates a lens holder whose inner surface expands in a trumpet shape in the shooting direction. The lens holder 3b is preferably a trumpet shape as illustrated in FIG. 6B in that the lens to be held is a wide-angle lens and a wide angle of view is effectively secured. As shown in FIG. 6B, the expansion angle α is preferably 50 ° or more, more preferably 55 ° or more, and more preferably 60 ° or more in that image information including a wide range of vein patterns can be acquired with one lens. Particularly preferred. On the other hand, since the peripheral region of the captured image is greatly deformed and has low luminance, the development angle α is preferably 75 ° or less, more preferably 73 ° or less, and more preferably 70 ° or less from the viewpoint of obtaining a highly accurate vein pattern. Particularly preferred. The inner surface of the lens holder is preferably mirror-finished in terms of increasing the light collection efficiency. A CCD image sensor or a CMOS image sensor can be used for the imaging device 3c.

  The imaging unit 3 illustrated in FIG. 6B includes an infrared transmission filter 3d. Therefore, in the mode shown in FIG. 6B, only the infrared light of the light passing through the close-up type wide-angle lens 3a is selectively transmitted by the infrared transmission filter 3d and reaches the image sensor 3c. Since the vein specifically absorbs near infrared rays, the region where the vein exists appears as a dark line with low luminance. On the other hand, since the region where no vein exists does not absorb near infrared rays, the luminance is maintained. Therefore, by providing the infrared transmission filter 3d and blocking light of wavelengths other than infrared rays, a vein (dark line) pattern with less noise and good contrast can be acquired. The infrared transmission filter 3d exhibits its function by being provided before the transmitted light from the finger reaches the image sensor 3c. Therefore, in addition to the embodiment illustrated in FIG. 6B, the infrared transmission filter 3d is disposed on the close-up type wide-angle lens 3a. The mode of arrangement is also effective.

  FIG. 12 is a conceptual diagram showing the structure of the reading means constituting the personal authentication device of the present invention, FIG. 12 (a) shows the structure when viewed from the side, and FIG. 12 (b) is from above. Shows the structure when viewed. As shown in FIG. 12A, in the imaging unit 3 constituting the personal authentication device of the present invention, the lens holder 3b opens in the shooting direction 3g, and the inner surface of the lens holder 3b faces in the shooting direction 3g. It has an expanding shape. That is, the lens holder 3b has an inner surface dimension L2 that increases toward the photographing direction 3b. Further, the close-up type wide-angle lens 3a is held at the root portion where the inner dimension of the lens holder 3b is short. Since the lens holder 3b has such a shape, it is possible to increase the effectiveness of the wide angle of view of the close-up type wide-angle lens 3a and to enlarge image information that can be collected by one lens.

  As shown in FIG. 12A, the lens holder 3b has a finger surface out of the light emitted from the light source unit 2 when the opening end 3e protrudes from the top of the light source unit 2 in the photographing direction 3g. This is preferable in that the reflected light transmitted through the line is suppressed and the contrast of the vein pattern is increased. From this viewpoint, the distance L3 from the opening end 3e of the lens holder 3b to the top of the light source unit 2 is preferably 0.3 mm or more, and more preferably 0.5 mm or more. On the other hand, since the light quantity from the light source part 2 will reduce when the distance L3 becomes large, the distance L3 is preferably 1.5 mm or less, and more preferably 1.0 mm or less.

  As shown in FIG. 12A, when the lens holder 3b includes a light-absorbing light-shielding material 3f inside the opening end 3e, the reflected light transmitted from the light source unit 2 to the finger surface is transmitted. It is preferable in that it is suppressed and the contrast of the vein pattern is increased. FIG. 12 illustrates a mode in which a plate-like body to which a black paint is applied is arranged as the light-absorbing light shielding material 3f. In the aspect shown in FIG. 12B, this plate-like body (absorbing light-shielding material 3f) is arranged at the opening end on the light source part 2 side of the opening end 3e of the lens holder 3b. FIG. 12B illustrates an example in which the light source unit 2 and the lens holder 3b are rectangular, and the lens holder 3b holds a close-up type wide-angle lens 3a.

  FIG. 7 is a conceptual diagram showing the structure of the reading means 1 constituting the personal authentication device of the present invention, and shows the structure when the reading means 1 is cut in the longitudinal direction of the finger 9. The mode illustrated in FIG. 7 is an external reading unit in which the light source unit 2 and the imaging unit 3 are arranged outside the member to which the reading unit 1 is attached. In the reading unit 1 illustrated in FIG. 7, the light source unit 2 and the imaging unit 3 have the top surface protected by the protection plate 5 and the side surfaces protected by the housing 6. The externally attached reading means is preferable in that it can be easily installed compared to the built-in reading means. In addition, in the external reading unit 1 illustrated in FIG. 7, the distance L from the surface with which the finger 9 abuts to the image sensor is 8.5 mm or less, and a personal authentication device including a thinned reading unit is provided. can do.

  FIG. 9 is a conceptual diagram showing the structure of the reading means 1 constituting the personal authentication device of the present invention, and FIG. 9A shows the structure when the reading means 1 is cut in the longitudinal direction of the finger 9. FIG. 9B shows a structure when the reading unit 1 is cut in a direction IXB-IXB orthogonal to the longitudinal direction of the finger 9 in FIG. 9A. The reading unit 1 illustrated in FIG. 9 includes a concave finger placement guide 7, and the light source unit 2 and the imaging unit 3 are arranged on the finger placement guide 7. The concave shape means a shape in which the central portion of the finger placement guide is depressed. Since the vein pattern in the finger 9 varies depending on the position of the finger, as shown in FIG. 9A, a finger placement guide 7 is provided, and the finger is placed along the finger placement guide, so that The distance D to the imaging unit 3 can be kept constant, and a vein pattern located at a distance D from the tip of the finger can be imaged. Therefore, the accuracy of personal authentication can be increased.

  Similarly, by providing a concave finger placement guide 7 as shown in FIG. 9B and placing the finger along the finger placement guide, the imaging location is constant in the finger width direction, and the location is constant. A certain vein pattern can be imaged. For this reason, the accuracy of personal authentication can be improved. In addition, when the finger placement guide 7 is formed of an opaque body, the effect of blocking ambient ambient light during imaging is enhanced, so that a vein pattern with less noise and good contrast can be acquired.

  Even in a mode in which the concave finger placement guide is not provided, it is possible to make the imaging location of the finger constant by displaying the location where the finger contacts. However, in the case of a reading means that does not have a concave finger placement guide and the surface on which the finger comes into contact is flat, pressing the finger against the contact surface reduces the blood in the pressurized area, so the contrast of the vein pattern May decrease. On the other hand, in the aspect provided with the concave finger placement guide, since the concave portion conforms to the shape of the finger, the pressure on the finger is dispersed, and a high-contrast vein pattern can be obtained.

  Although FIG. 9 illustrates an external reading unit, the same applies to a built-in reading unit in which the light source unit 2 and the imaging unit 3 are arranged inside a member to which the reading unit 1 is attached. Further, in the built-in type reading means, the finger placement guide is not limited to a mode in which the finger placement guide is disposed inside the member to which the reading means is attached, and also in a mode in which part of the finger placement guide is exposed to the outside of the member. Works effectively.

  FIG. 8 is a conceptual diagram showing the structure of the reading means constituting the personal authentication apparatus of the present invention, and shows the structure when the reading means 1 is cut in the longitudinal direction of the finger 9. In the aspect illustrated in FIG. 8, the light source unit 2 is configured such that the optical axis A of the irradiated light is inclined outward as viewed from the imaging unit 3 that is parallel to the light source unit. By tilting the light source unit 2 outward as viewed from the imaging unit 3, the reflected light that reaches the imaging unit 3 along the surface of the finger 9 out of the light emitted by the light source unit 2 is reduced. Therefore, noise in the imaging unit 3 is reduced, and a vein pattern with good contrast can be acquired.

  In addition, by tilting the light source unit 2 to the outside, it is possible to reduce an aspect in which light scattered in a shallow region of a finger with few veins reaching the imaging unit among light incident on the finger from the light source unit. For this reason, a vein pattern with less noise and good contrast can be obtained. An angle formed by the imaging direction of the imaging unit 3 and the optical axis A of the light source unit 2 is defined as an inclination angle β. When the inclination angle β is large, it is necessary to increase the amount of light source irradiated by the light source unit 2, and therefore the inclination angle β is usually preferably 30 ° to 50 °, although it depends on the presence or absence of the light shielding partition 4. On the other hand, when the reading means is attached to the member, the mode in which the reading means is arranged for each finger so that each vein pattern can be read from a plurality of fingers can perform more accurate personal authentication based on the vein patterns of the plurality of fingers. This is preferable.

  By attaching the reading means to the door lever, the steering wheel of the vehicle, the mobile phone or the case of the mobile phone, it becomes possible to perform personal authentication of a specific person who holds them. FIG. 10 is an explanatory view showing an example in which the reading means constituting the personal authentication device of the present invention is attached to the door lever. In the example shown in FIG. 10, the built-in type reading means 21 is attached to the door lever 25 arranged on the door 20. However, the embodiment is similarly effective in an aspect in which an external type reading means is attached. The reading means 21 are arranged in a total of three, and the reading means 21a is designed to acquire a vein pattern from the index finger (: index finger), the reading means 21b is the middle finger, and the reading means 21c is obtained from the ring finger (: ring finger). Yes. For this reason, more accurate personal authentication is possible based on a plurality of finger vein patterns. The reading unit 21a includes three light source units 22 and an imaging unit 23, and the reading units 21b and 21c have the same configuration.

  When a specific person grips the door lever illustrated in FIG. 10 with a finger, personal authentication is possible. After personal authentication, the door can be unlocked. Similarly to a door lever, a vehicle steering wheel that is gripped and operated by a finger can be used to authenticate the driver by attaching a reading means as shown in FIG. The reading means constituting the personal authentication device of the present invention is thin and can be easily attached to a door lever, a steering wheel of a vehicle, or the like because the attachment place is not selected.

  FIG. 11 is an explanatory view showing an example in which the reading means constituting the personal authentication device of the present invention is attached to a case of a mobile phone such as a smartphone. In the example shown in FIG. 11, the built-in reading means 31 is attached to the case 30 of the mobile phone, but the same applies to the case where an external reading means is attached. Although one reading means 31 is attached for the index finger (index finger), as shown in FIG. 10, a mode in which a plurality of reading means are attached to acquire information from a plurality of fingers is also possible. The reading unit 31 includes a light source unit 32, an imaging unit 33, and a light blocking partition 34, and has a concave finger placement guide 37 around it. The authentication means can be mounted on a mobile phone.

  When a specific person holds the case 30 shown in FIG. 11 with a finger, personal authentication is possible, and after the personal authentication is completed, a setting such as starting a mobile phone can be performed. Further, since the reading unit 31 includes the concave finger placement guide 37, the accuracy of personal authentication can be increased. Although FIG. 11 shows an example in which reading means is attached to the case of the mobile phone, personal authentication can be performed by attaching the reading means to the casing of the mobile phone, as in FIG. The reading means constituting the personal authentication apparatus of the present invention is thin, has few restrictions on the mounting location, and can be easily attached to a mobile phone, a case of a mobile phone, or the like.

  FIG. 3 is an example of a flowchart for implementing the personal authentication apparatus of the present invention. The personal authentication apparatus performs personal authentication in cooperation with hardware. As shown in FIG. 3, the reading unit first acquires imaging information of a specific person's finger (step S21), and transmits the acquired imaging information to the authentication unit (step S22). The authentication unit is configured to be able to receive imaging information from the imaging unit of the reading unit. When the authentication unit receives the imaging information (step 1), the CPU records the imaging information in a memory, and then A vein pattern is extracted from the imaging information (step S2), and the vein pattern is recorded in the memory.

  Extraction of the vein pattern from the imaging information is performed by a method of repeatedly tracking the dark line, a method of enhancing the pattern by filter processing, or the like. For example, in the method of repeatedly performing the tracking of the dark line, since the hemoglobin constituting the red blood cells flowing in the vein has a property of absorbing near infrared rays, the vein has a dark line having darker brightness than the surroundings in the photographed image of the finger. And appear. Therefore, the movement is performed pixel by pixel along the dark line from an arbitrary point in the photographed image until the line cannot be detected. This operation is repeated and the number of times traced for each pixel is recorded. Thereafter, the vein pattern is extracted by labeling the vein region and the background region. On the other hand, the method of emphasizing a pattern by filter processing is a method of extracting features of a vein pattern by filtering imaging information and enhancing contrast.

  Thereafter, as shown in FIG. 3, the authentication means searches whether there is authentication data corresponding to the extracted vein pattern (step S3), and if the corresponding authentication data is in the database, the authentication means is the person himself / herself. This is confirmed (personal authentication) (step S4). In the search for the corresponding authentication data (step S3), the CPU accesses the database and acquires the authentication data recorded in advance in the database. Next, the authentication data is recorded in the memory, and the authentication data corresponding to the extracted vein pattern is retrieved from the recorded authentication data. In this specification, “data corresponds” means not only the case where both data match, but also the case where the matching rate of both data is equal to or higher than a predetermined threshold value by the matching process. If there is no authentication data corresponding to the extracted vein pattern, personal authentication is not performed because it is not possible to confirm the identity.

  The collation between the vein pattern extracted by the dark line tracking method or the like and the authentication data recorded in the database is performed by, for example, the template matching method. First, binarization processing is performed on the extracted vein pattern image to emphasize the vein pattern. Next, the corresponding pixel values are compared between the binarized image and the authentication data, and the coincidence rate is calculated. The matching rate is the ratio of the number of pixels having a corresponding pixel value to the total number of pixels. If the match rate is equal to or higher than a predetermined threshold, the user is authenticated. Further, when performing personal authentication, the matching rate between the extracted vein pattern and the authentication data varies due to the position of the finger being displaced. For this reason, it is possible to employ a method in which collation is performed a plurality of times, the coincidence rate is calculated each time, and collation is performed based on the maximum value. It is preferable that the extracted vein pattern image is binarized and then subjected to a spatial compression process in order to increase the processing speed.

  FIG. 5 is an example of a database constituting authentication means in the personal authentication apparatus of the present invention. As shown in FIG. 5, authentication data related to the vein pattern of a specific person's finger is recorded in advance in the database, and an index is assigned to each specific person. The authentication data shown in FIG. 5 is input to the database in advance using an optical disk, a magnetic disk, or the like. Also, it is possible to transmit the imaging information of the finger of the specific person acquired by the reading unit to the authentication unit, extract a vein pattern from the imaging information, and register the extracted vein pattern in the database as authentication data.

  Using the index shown in FIG. 5 has the following advantages. An index is input in advance when performing personal authentication. The CPU accesses the database and obtains only the authentication data to which the same index is assigned from the authentication data recorded in advance in the database. The CPU records the single authentication data in the memory, confirms the correspondence between the single authentication data and the extracted vein pattern, and performs personal authentication. This aspect is preferable in that the personal authentication can be made efficient.

  A mode of notifying that the personal authentication is completed after the personal authentication is completed is preferable in that the completion of the authentication can be objectively confirmed. As a notification means, for example, notification by voice saying “Personal confirmation has been completed”, generation of a melody such as a chime, lighting of a display lamp, display on a display, etc. can be used and used together. Further, it is possible to transmit the fact that the personal authentication is completed to the outside of the personal authentication device, for example, a security company or a living person.

  Since the reading means constituting the personal authentication device of the present invention is thin, it can be easily attached to a door lever, a steering wheel of a vehicle, a mobile phone or a case of a mobile phone, and personal authentication is possible.

DESCRIPTION OF SYMBOLS 1 Reading means 2 Light source part 3 Image pick-up part 3a Close-up type wide-angle lens 3b Lens holder 3c Image pick-up element 3d Infrared transmission filter 3e Open end 3f Absorbing light-shielding material 3g Shooting direction 4 Partition (for light-shielding) 5 Protection plate 7 Finger placement guide 9 Finger 20 Door 25 Door Lever 30 Case (for cellular phone) 40 Opening 41 Finger 42 Reading means 43 Light source 44 Acrylic plate 45 Finger rest 47 Infrared transmission filter 49 Imaging device 111 Input means 112 Control means 113 Display means 114 Storage means 115 Output means 121 Input circuit 122 CPU
123 display 124 database 125 output circuit 126 memory 130 reading means 131 OS
134 Authentication data

Claims (13)

It is a personal authentication device that reads the vein pattern of the abutting finger and verifies the identity based on the vein pattern,
Reading means for reading information including a finger vein pattern;
Authentication means having a database pre-recorded with authentication data for finger vein patterns;
With
The reading means includes
It has a set of light source unit and image pickup unit arranged in parallel in the longitudinal direction of the finger that contacts,
The imaging unit
A close-up type wide-angle lens, a lens holder, and an image sensor;
The lens holder has a shape that opens toward the shooting direction, and has an inner surface that expands toward the shooting direction, and holds the close-up wide-angle lens at a root portion with a short inner dimension;
The imaging unit picks up light passing through the finger and passing through the close-up type wide-angle lens among light incident on the finger from the light source unit,
The authentication means includes
It is configured to be able to receive imaging information from the imaging unit,
When imaging information is received from the imaging unit,
Extract vein patterns from imaging information,
A personal authentication device that verifies the identity of a person when authentication data corresponding to the extracted vein pattern is in the database.   The personal authentication device according to claim 1, wherein the close-up wide-angle lens has an angle of view of 100 ° to 150 °.   The personal authentication device according to claim 1, wherein the close-up type wide-angle lens has a focal length of 0.5 mm to 1.5 mm.   The personal authentication device according to any one of claims 1 to 3, wherein when the reading unit contacts the finger, a distance from the contact surface of the finger to the imaging element is 8.5 mm or less.   5. The personal authentication device according to claim 1, wherein the light source unit is configured such that an optical axis of light to be irradiated is inclined outward as viewed from an imaging unit parallel to the light source unit.   The personal authentication device according to claim 1, wherein the reading unit arranges a plurality of light source units with the imaging unit interposed therebetween.   The personal authentication device according to claim 1, wherein the reading unit includes a concave finger placement guide, and the light source unit and the imaging unit are arranged on the finger placement guide.   The personal authentication device according to claim 1, wherein the reading unit is arranged for each finger so that the vein pattern can be read from a plurality of fingers.   The personal authentication device according to claim 1, wherein the reading unit includes a light-shielding partition wall between the light source unit and the imaging unit.   The personal authentication device according to claim 1, wherein an inner surface of the lens holder expands in a trumpet shape toward the photographing direction.   The personal authentication device according to any one of claims 1 to 10, wherein an open end of the lens holder protrudes from the top of the light source unit in the imaging direction by 0.3 mm to 1.5 mm.   The personal authentication device according to claim 1, wherein the lens holder includes a light-absorbing light-shielding material inside the opening end.   The personal authentication device according to claim 1, wherein the reading unit is arranged on a door lever, a steering wheel of a vehicle, a mobile phone, or a case of the mobile phone.

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