JP2004234040A - Personal authentication device - Google Patents

Abstract

An object of the present invention is to provide a means for solving a problem that cannot be registered or cannot be authenticated in a personal authentication device using a blood vessel pattern of a finger or a fingerprint pattern with an inexpensive and simple configuration.
An image sensor (31) irradiates a finger with a fingerprint pattern and an infrared light source (33), and obtains two types of biological information of a finger blood vessel pattern obtained by transmission.
According to the present invention, it is possible to realize a personal authentication apparatus capable of imaging both a blood vessel pattern and a fingerprint pattern of a finger with a single image sensor with an inexpensive and simple configuration and switching an authentication method as needed. .
[Selection diagram] Fig. 1

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a personal authentication device that uses human biological information as a specific means for an individual.
[0002]
[Prior art]
Conventionally, for example, a key is used for unlocking and starting a door of an automobile, and it is known that a key is inserted into an ignition switch 41 and the automobile is shifted to a starting state by rotating the key. At this time, if the key is stolen, or the keyhole is picked, there is a possibility that a malicious person other than the owner of the car may drive the vehicle. In order to prevent picking or use of duplicate keys, as described in Japanese Patent Application Laid-Open No. 2000-108848, only an engine having an IC called a transponder embedded in a key can start the engine. There is a method of starting an automobile equipped with an immobilizer function. In order to further enhance security, a method of unlocking and starting a door of an automobile using biometric information has been studied. For example, Japanese Unexamined Patent Publication Nos. 61-52972 and 6-72291 disclose methods. There is a way.
[0003]
As a personal authentication device using this biometric information, a method using a different fingerprint for each individual is most known. As an example of this, there are many methods such as the method disclosed in JP-A-54-85600.
[0004]
Further, as another personal authentication device using other biometric information, a method of personal authentication using a finger blood vessel pattern described in JP-A-2001-184507 can be used. In this method, an imaging system including a lens and an image sensor (image sensor) is used as an imaging unit for imaging a blood vessel pattern of a finger, and authentication is performed when the finger blood vessel pattern to be authenticated matches the registered finger blood vessel pattern.
[0005]
[Patent Document 1]
JP 2000-108848 A [Patent Document 2]
Japanese Patent Application Laid-Open No. 61-53872 [Patent Document 3]
JP-A-6-72291 [Patent Document 4]
JP-A-54-85600 [Patent Document 5]
JP 2001-184507 A
[Problems to be solved by the invention]
By the way, in the personal authentication device using a fingerprint pattern, depending on the individual, the fingerprint pattern cannot be registered due to a blurred fingerprint, or even if the fingerprint pattern is registered, the finger is dry at the time of authentication, or It has been pointed out that personal authentication cannot be performed due to a change in the condition of the fingertip at the time of registration, such as when it is wet.
[0007]
In addition, a problem has been pointed out that a forged finger can be produced by an inexpensive method.
[0008]
On the other hand, in the authentication method using the blood vessel pattern of the finger, since the information inside the finger called the blood vessel pattern is used, it is difficult to forge and there is no problem due to the dryness or wetness of the finger. It may be difficult to be authenticated because the flow is reduced.
[0009]
Therefore, an object of the present invention is to provide a means for solving the above-mentioned problem with an inexpensive and simple configuration.
[0010]
[Means for Solving the Problems]
In the present invention, in order to achieve the above object, only one imaging unit for imaging biological information is provided. However, this imaging unit enables imaging of two or more types of biological information, and identifies an individual. Configuration. In particular, two types of biological information of a fingerprint pattern and a finger blood vessel pattern obtained by irradiating a finger with an infrared light source and transmitting the finger are easy to adopt a configuration in which both pieces of information can be obtained by one imaging unit. Therefore, it is possible to configure an individual authentication device at low cost using personal biometric information of both a blood vessel pattern and a fingerprint pattern. Further, in the personal authentication device using the blood vessel pattern, since the transmitted light of the living body is used, it is possible to distinguish whether it is a living body or not by imaging this information. It can be used for counterfeit finger measures without the addition of.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail.
[0012]
FIG. 1 shows an example of a configuration diagram in which a personal authentication device using a finger blood vessel pattern and a fingerprint pattern is applied to a starting system of an automobile. The personal authentication device 3 shown in FIG. 1 is an example of an authentication device using a finger blood vessel pattern, and includes a microcomputer 30, an image sensor 31, a lens 32, infrared light sources 33 and 34, an infrared transmission filter 35, an infrared light source. It comprises a drive circuit 37 of 33 and 34, a nonvolatile memory 36 connected to the microcomputer 30, and a power supply circuit 38.
[0013]
When performing personal authentication using a finger blood vessel pattern, the finger 7 to be authenticated is placed between the infrared light source 33 and the infrared transmission filter 35. When the microcomputer 30 drives the drive circuit 37 to turn on the infrared light source 33, the infrared light is absorbed by the hemoglobin of blood, so that a blood vessel pattern is formed on the image sensor 31. In addition, the infrared transmission filter 35 has a characteristic of cutting visible light that is noise to obtain a blood vessel pattern and transmitting only infrared light including the blood vessel pattern. FIG. 2 shows an imaging example 70a of the finger 7 and the blood vessel pattern 71 imaged by the image sensor 31. Since the blood vessel pattern 71 differs depending on the individual, the individual can be specified by registering the blood vessel pattern 71 in the nonvolatile memory 36 in advance and determining whether the registered pattern matches the authentication pattern at the time of authentication.
[0014]
On the other hand, when performing personal authentication using a fingerprint pattern, the finger 7 to be authenticated is placed at the same position as the personal authentication using the blood vessel pattern of the finger. When the infrared light source 33 is turned off, the surface of the finger 7 is formed on the image sensor 31. FIG. 3 shows an imaging example 70b of the finger 7 and the fingerprint pattern 72 imaged by the image sensor. Since the fingerprint pattern 72 is also different for each individual, the individual can be specified by registering the fingerprint pattern 72 in the nonvolatile memory 36 in advance and determining whether or not the registered pattern and the authentication pattern match or not at the time of authentication. The infrared light source 34 is turned on as necessary for the purpose of obtaining sufficient brightness to obtain the fingerprint pattern 72.
[0015]
The blood vessel pattern 71 or the fingerprint pattern 72 captured by the image sensor 31 is photoelectrically converted into an electric signal, which is taken into the microcomputer 30. When the ignition switch 41 is ON, the power supply 44 is supplied to the power supply circuit 38 from the outside. Further, it is configured to be connected to the engine control device 42 via a LAN. Further, as an option, the microcomputer 30 is configured to be able to communicate with the IC card reader or the immobilizer 43.
[0016]
The operation of the personal authentication device 3 for starting the engine of the vehicle is controlled by a program stored in the microcomputer 30 shown in FIG. The operation of the microcomputer 30 will be described with reference to the flowchart of FIG. Note that this flowchart can be basically performed by the same processing for both the finger blood vessel pattern and the fingerprint pattern.
[0017]
When the ignition switch 41 shifts to the ON state, power is supplied to the entire personal authentication device 3 and the operation starts. The microcomputer 30 starts operating according to the program stored in the built-in memory. First, necessary initialization is performed in step S1. The contents of the initialization processing include, for example, initialization of an internal memory, initialization of the image sensor 31, and the like. Next, in step S2, it is determined whether the finger 7 to be authenticated has been placed at a predetermined position. If the finger 7 is not placed, the process returns to step S2. If so, the process proceeds to step S3, where characteristic parameter extraction processing of the finger blood vessel pattern 71 or the fingerprint pattern 72 is performed. Details of this processing will be described later. Next, the process proceeds to step S4, where the extracted characteristic parameters are compared with one or more parameters stored in the nonvolatile memory 36 in advance. In step S5, the collation result is determined. If there is no matching parameter, the process returns to step S2 as an unregistered person or as a verification failure. If the verification results match, it means that the vehicle has been authenticated as a legitimate driver. Next, the process proceeds to step S6, in which a start permission command is issued to the engine control device 42 via the LAN, and the engine is started.
[0018]
FIG. 5 illustrates details of the process of step S3 in FIG. First, in step S3a, the infrared light source 33 or 34 that illuminates the finger 7 is turned on by the drive circuit 37. Next, in step S3b, the image formed on the image sensor 31 is taken into the microcomputer 30. Next, in step S3c, the infrared light source 33 or 34 is turned off. Next, in step S3d, the microcomputer 30 performs arithmetic processing on the obtained image to extract characteristic parameters of the blood vessel pattern 71 or the fingerprint pattern 72.
[0019]
In this personal authentication device 3, the registered biometric information can be selected by each individual. That is, it is possible to register either (1) only the finger blood vessel pattern, (2) only the fingerprint pattern, or (3) both the finger blood vessel pattern and the fingerprint pattern. It is assumed that there are a plurality of users in an automobile, and it is possible to use different registration methods (1) to (3) for each individual. In some rare cases, only the finger blood vessel pattern of (1) or only the fingerprint pattern of (2) can be registered depending on the individual. Therefore, at the time of authentication, the flowchart in FIG. 4 is changed to a flowchart as shown in FIG. 6. For example, first, authentication is performed using a blood vessel pattern of a finger, and if they do not match, authentication is performed using a fingerprint pattern. Of course, the order of the authentication by the finger blood vessel pattern and the fingerprint pattern may be exchanged, and the authentication by the fingerprint pattern may be performed first. In addition, when both patterns of (3) are registered, even if the authentication result does not match for some reason in the first verification process regardless of the registrant, the verification process is performed by the other authentication method. Is possible, and the registrant can be authenticated.
[0020]
Also, when both patterns are registered as in (3), as shown in the flowchart of FIG. 7, first, the matching process is performed on the finger blood vessel pattern. The processing may be such that the engine is started only when the values match. Thus, since two types of biological information are used, the anti-theft property of the vehicle can be improved. Which of the flowcharts in FIGS. 6 and 7 is to be used may be determined at the time of registration of an individual, or may be configured to allow switching after registration as needed.
[0021]
By the way, it has been pointed out that a personal authentication device using a fingerprint pattern can produce a forged finger by an inexpensive method. In the configuration of the personal authentication device 3 shown in FIG. 1, the transmitted light intensity characteristic of the finger can be measured using the infrared light source 33 for imaging a blood vessel pattern. Accordingly, even if the authentication result using the fingerprint pattern matches, if it is determined that the finger is not a finger based on the transmitted light intensity, the authentication is set to NG, thereby avoiding the problem that the authentication result matches with the counterfeit finger. it can.
[0022]
In the present embodiment, an example in which the personal authentication device using the blood vessel pattern of the finger and the fingerprint pattern is applied to the starting system of an automobile has been described. However, the present invention is also applicable to a personal authentication device for entry control of a house or a building. It is possible. Also, the personal authentication device using the finger blood vessel pattern and the fingerprint pattern has been described as an example, but the invention can also be applied to a personal authentication device using iris authentication or the like by devising the attachment of the image sensor.
[0023]
【The invention's effect】
According to the present embodiment, it is possible to realize a personal authentication device capable of imaging two types of images, that is, a blood vessel pattern of a finger and a fingerprint pattern, with a single image sensor by using an inexpensive and simple configuration. When registration and authentication cannot be performed by the type of authentication method, another type of authentication method can be easily used.
[0024]
Further, in a personal authentication device using a fingerprint pattern, it is possible to avoid a problem that authentication results match with a counterfeit finger with an inexpensive configuration.
[Brief description of the drawings]
FIG. 1 is an example of a configuration diagram in which a personal authentication device according to an embodiment of the present invention is applied to a starting system of an automobile.
FIG. 2 is an imaging example of a finger and a blood vessel pattern.
FIG. 3 is an imaging example of a finger and a fingerprint pattern.
FIG. 4 is a program operation flowchart of a microcomputer of the personal authentication device.
FIG. 5 is a flowchart illustrating processing of characteristic parameters.
FIG. 6 is a program operation flowchart of a microcomputer of the personal authentication device.
FIG. 7 is a program operation flowchart of a microcomputer of the personal authentication device.
[Explanation of symbols]
3 ... personal authentication device, 7 ... finger, 30 ... microcomputer, 31 ... image sensor, 32 ... lens, 33, 34 ... infrared light source, 71 ... blood vessel pattern, 72 ... fingerprint pattern.

Claims (7)

A personal authentication device comprising an image pickup means for picking up personal biometric information, wherein a personal authentication device for specifying an individual from the information is configured to image two or more types of biometric information. 2. The personal authentication device according to claim 1, wherein the imaging device is provided with only one of the imaging devices and configured to image two or more types of biometric information. 3. The method according to claim 1, wherein the imaging unit is configured to obtain two types of biological information of a fingerprint pattern and a finger blood vessel pattern obtained by irradiating a finger with an infrared light source and transmitting the finger. Personal authentication device. 4. The personal authentication device according to claim 1, wherein each individual can select any one type of registration or authentication method. 4. The personal authentication device according to claim 1, wherein when any one of the authentication results does not match, the individual is specified by another authentication method. 4. The personal authentication apparatus according to claim 1, wherein when the identification of the individual by two or more types of authentication methods does not match, the identification of the individual is not performed. In a personal authentication device that includes an imaging unit that captures a fingerprint pattern and specifies an individual from the information, an infrared light source is further arranged on the nail side, irradiated, and the transmitted light intensity is obtained. A personal authentication device comprising means for determining

Images