JP4254330B2 - Image photographing device, image photographing method, and authentication device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an image capturing apparatus that captures an image of a subject, and an authentication apparatus that authenticates the subject using authentication information acquired from the captured image.
[0002]
[Prior art]
In recent years, when restricting access to important information such as personal information and confidential information, and managing entry / exit to highly secure rooms, it is unique to each human body such as iris, fingerprint, face or retina Authentication apparatuses that perform personal authentication using information (so-called biometric information) as authentication information have been put into practical use.
[0003]
For example, an image of an object around the eye (hereinafter referred to as an eye image) is taken, and authentication information is created by encoding the iris portion of the eye image. The authentication information acquired from the object is registered in advance. An iris authentication technique for authenticating a subject by comparing and verifying the authentication information has been proposed and put into practical use (see, for example, Patent Document 1).
[0004]
In such an authentication device using the iris authentication technology (hereinafter referred to as an “iris authentication device”), various device configurations such as a stationary type and a handy type have been proposed depending on the application. In the iris authentication device used, how to properly guide the position of the eye of the subject to fall within the angle of view of the image capturing unit of the iris authentication device has been a major issue.
[0005]
In order to solve this problem, for example, in a hand-held iris authentication apparatus, two mirrors are arranged in advance at a predetermined position of the iris authentication apparatus, and the person to be authenticated has two eyes of the iris authentication apparatus. There has been proposed a configuration in which the position of the eye can be guided to an appropriate position by moving the apparatus by itself in a position reflected in the mirror (see, for example, Patent Document 2).
[0006]
[Patent Document 1]
Japanese Patent No. 3307936
[Patent Document 2]
JP 2000-207536 A
[0007]
[Problems to be solved by the invention]
However, in the handy type iris authentication apparatus as described above, when the subject who is the person to be authenticated wears glasses, no effective countermeasure has been taken for the detection.
[0008]
Further, in general, in an iris authentication apparatus, in order to capture an image of an iris pattern with high contrast, the eye of the subject is irradiated with near infrared light (wavelength of about 700 nm to about 1000 nm), and a reflection image thereof is captured. For this reason, when the subject wears spectacles, near-infrared light applied to the eye is reflected by the front and back surfaces of the spectacle lens (hereinafter abbreviated as the lens surface) and the reflected image is reflected. Taken. Since this reflection has an adverse effect on the iris portion of the eye image, there is a problem that an image having a good iris pattern cannot be reliably captured.
[0009]
In view of such a problem, the present invention provides an image capturing apparatus capable of detecting when a subject is wearing glasses and capturing a good iris pattern image in a handy type authentication apparatus, and the same An object of the present invention is to provide an authentication device using the.
[0010]
[Means for Solving the Problems]
  An image capturing apparatus according to the present invention includes an image capturing unit that captures an image of a subject at a position where shooting distances are different from each other, and an in-focus degree that calculates a degree of focus of each of a plurality of images captured by the image capturing unit. The plurality of images when the calculation unit, the spectacle wear determination unit that determines whether or not the subject wears spectacles, and the spectacle wear determination unit determine that the subject wears spectacles Among them, an in-focus image determination unit that determines that an image in which the degree of focus is equal to or greater than a predetermined threshold at a position closest to the subject is an in-focus image of the eye, and a light beam irradiation unit that irradiates the subject with a light beam The light beam irradiation control unit increases the intensity of the light beam applied to the light beam irradiation unit when the focus level exceeds a predetermined threshold in the focus level calculation unit. It is a feature.
[0011]
  With such a configuration, since the glasses wearing determination unit is provided, it can be determined whether or not the subject is wearing glasses. Furthermore, when it is determined that the subject wears spectacles in the spectacle wearing determination unit, the degree of focus is equal to or greater than a predetermined threshold and the image with the shortest shooting distance is determined as the focused image. The adverse effect of the reflection image on the lens surface of the spectacles on the eye image, particularly the iris image, can be reduced, and an in-focus image of the eye having a good iris pattern can be obtained. Furthermore, the intensity of the light beam applied to the light beam irradiation unit can be increased, and the intensity of the light beam is increased in the light beam irradiation unit after the degree of focus exceeds a predetermined threshold. It is possible to shoot an image and the intensity of the light beam may be low until a predetermined degree of focus is obtained, so that power consumption can be reduced, and image shooting suitable for mounting on a handheld device. A device can be realized.
[0012]
  Next, the image capturing apparatus of the present invention calculates an in-focus level of an image capturing unit that captures an image of a subject at a position where the shooting distance is different from each other, and a plurality of images captured by the image capturing unit. A degree-of-focus calculation unit, a spectacle wearing determination unit that determines whether or not the subject is wearing spectacles, and when the spectacle wearing determination unit determines that the subject is wearing spectacles, Among the plurality of images, the relationship between the shooting distance and the degree of focus of the image is such that the focus degree changes to show the first maximum as the subject approaches, and then shows the second maximum. A focused image that, when changed, determines that an image in which the degree of focus is equal to or greater than a predetermined threshold and the shooting distance is closer than the shooting distance corresponding to the second maximum is the focused image of the eye. Judgment part and,
A light beam irradiation unit configured to irradiate the subject with a light beam, and the light beam irradiation control unit irradiates the light beam irradiation unit when the focus level exceeds a predetermined threshold in the focus level calculation unit. It is characterized by increasing the intensity of light rays.
[0013]
  With such a configuration, since the glasses wearing determination unit is provided, it can be determined whether or not the subject is wearing glasses. Further, when the spectacle wearing determination unit determines that the subject wears spectacles, the degree of focus is equal to or greater than a predetermined threshold, and the shooting distance is closer than the shooting distance corresponding to the second maximum. Since the image is determined to be an in-focus image, it is possible to obtain a good eye-focused image in which the adverse effect of the reflected image on the lens surface of the spectacles on the eye image, particularly the iris image, is reduced. Furthermore, the intensity of the light beam applied to the light beam irradiation unit can be increased, and the intensity of the light beam is increased in the light beam irradiation unit after the degree of focus exceeds a predetermined threshold. It is possible to shoot an image and the intensity of the light beam may be low until a predetermined degree of focus is obtained, so that power consumption can be reduced, and image shooting suitable for mounting on a handheld device. A device can be realized.
[0014]
In addition, when the spectacle wearing determination unit determines that the subject does not wear spectacles, the in-focus image determination unit has a degree of focus equal to or greater than a predetermined threshold at a position farthest from the subject among the plurality of images. According to the configuration in which it is determined that the image to be an in-focus image is an eye-focused image, it is possible to obtain a focused image with a good iris pattern when the subject is a naked eye who is not wearing glasses. Regardless of the presence or absence of the image, it is possible to obtain a focused image of the eye suitable for authentication.
[0015]
The glasses wearing determination unit is configured to determine that the subject is wearing glasses when there are a predetermined number or more of pixels having a predetermined luminance or higher among images captured by the image capturing unit. Also good.
[0016]
According to such a configuration, it is possible to determine whether or not the person to be authenticated wears glasses without performing input or the like by the person to be authenticated who is the subject.
[0017]
Further, an input unit connected to the spectacle wearing determination unit may be provided, and the spectacle wearing determination unit may determine that the subject wears spectacles when a predetermined input is made to the input unit. .
[0018]
By adopting such a configuration, it is possible to determine wearing of glasses with a simple configuration, and an image capturing apparatus that is easy for the user to use can be realized.
[0023]
Moreover, the structure provided with the guidance information output part which outputs the guidance information which guide | induces a photographing distance to the distance which can obtain a focused image with respect to a to-be-photographed object may be sufficient.
[0024]
With such a configuration, guidance information for guiding the person to be authenticated to a position where a focused image can be obtained is output. The burden at the time of moving to the position where can be obtained can be reduced.
[0025]
Further, a guidance information output control unit that causes the guidance information output unit to modulate and output the frequency of the voice information based on the level of the focus degree calculated by the focus degree calculation unit is information by voice. The structure provided may be sufficient.
[0026]
By adopting such a configuration, it is possible to realize a configuration in which the frequency of the voice information increases as the degree of focus increases, and conversely, a configuration in which the frequency decreases. Therefore, a guidance method with less burden on the person to be authenticated can be realized.
[0027]
Furthermore, the structure by which the irradiation light irradiated from a light irradiation part is near infrared light may be sufficient.
[0028]
With such a configuration, it is possible to capture a high-contrast image of the iris.
[0029]
Next, the authentication device of the present invention is stored in the above-described image photographing device of the present invention, the focused image storage unit that stores the focused image determined by the focused image determination unit, and the focused image storage unit. An authentication information creation unit that creates authentication information from a focused image, and a comparison / collation unit that compares and collates pre-registered registration authentication information and authentication information created by the authentication information creation unit. .
[0030]
With such a configuration, it is possible to detect the eyeglasses of the person to be authenticated with a simple configuration, and it is possible to capture a good eye image even when the glasses are worn, and a small authentication device with a high authentication rate. realizable.
[0031]
The authentication information creation unit may be configured to create authentication information by coding an iris image obtained from the image of the person to be authenticated.
[0032]
  With such a configuration, a high authentication rate can be realized using authentication information obtained by encoding an iris image.
  Next, according to the image capturing method of the present invention, an image capturing step of capturing an image of a subject at a position where the capturing distance is different from each other, and a degree of focus of each of the plurality of images captured in the image capturing step are calculated. When it is determined that the subject wears spectacles in the in-focus degree calculation step, the spectacle wear determination step that determines whether or not the subject wears spectacles, and the spectacle wear determination step, Of the plurality of images, an in-focus image determination step for determining that an in-focus image is equal to or greater than a predetermined threshold at a position closest to the subject is an eye-focused image, and irradiating the subject with light rays A light beam irradiation step, wherein the light beam irradiation control step is performed when the focus degree exceeds a predetermined threshold in the focus degree calculation step. It is characterized by increasing the intensity of the irradiated light.
With such a configuration, since the glasses wearing determination step is provided, it can be determined whether or not the subject wears glasses. Furthermore, when it is determined in the spectacle wearing determination step that the subject is wearing spectacles, the degree of focus is equal to or greater than a predetermined threshold and the image with the shortest shooting distance is determined as the focused image. The adverse effect of the reflection image on the lens surface of the spectacles on the eye image, particularly the iris image, can be reduced, and an in-focus image of the eye having a good iris pattern can be obtained. Furthermore, the intensity of the light beam applied to the light beam irradiation step can be increased, and the intensity of the light beam is increased in the light beam irradiation step after the in-focus degree exceeds a predetermined threshold value. It is possible to shoot an image and the intensity of the light beam may be low until a predetermined degree of focus is obtained, so that power consumption can be reduced, and image shooting suitable for mounting on a handheld device. A method can be realized.
[0033]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, as an embodiment of the present invention, an image photographing device and an authentication device of the present invention will be described with reference to the drawings.
[0034]
FIG. 1 is a block diagram showing a configuration of an image capturing device and an authentication device according to an embodiment of the present invention. FIG. 2 is a diagram for explaining how to use the authentication apparatus according to the embodiment of the present invention. Further, FIG. 3 is a diagram showing an external appearance of a mobile phone device equipped with the authentication device according to the embodiment of the present invention.
[0035]
First, the image photographing device 1 of the present invention photographs the eye 2 of the person to be authenticated and outputs a focused eye image (hereinafter referred to as a focused image). Further, the authentication device 3 of the present invention authenticates the person to be authenticated by creating an iris code as authentication information from the image output from the image capturing device 1 and comparing it with registered authentication information stored in advance. . As shown in FIG. 2, the authentication device 3 of the present invention performs image shooting and authentication while the person to be authenticated holds the casing in his hand.
[0036]
Returning to FIG. 1, the image capturing apparatus 1 according to the embodiment of the present invention captures an eye image of a person to be authenticated at a fixed time, for example, every 1/30 second, at a position where the shooting distance is different from each other. Connected to the image photographing unit 4 for photographing the image, the focus degree calculating unit 5 for calculating the degree of focus of the image photographed by the image photographing unit 4 (hereinafter referred to as the degree of focus), and the image photographing unit 4. The focus calculated by the eyeglass wear determination unit 6 and the focus degree calculation unit 5 that determines that the person to be authenticated wears the glasses when a portion having a predetermined luminance or higher is detected in the captured image. The in-focus image determination unit 7 that determines whether the image captured by the image capturing unit 4 is a focused image, depending on whether or not the degree is equal to or greater than a predetermined threshold value. A light beam irradiating unit 8 for irradiating external light, and a light beam controlling the intensity of the light beam emitted from the light beam irradiating unit 8 Control unit 9, the guidance information output unit 10 for outputting guidance information to be described later with respect to the person to be authenticated, and includes a guidance information output control section 11 for controlling the output of the guide information outputted from the guide information output section 10.
[0037]
The image photographing unit 4 can be realized by a known device capable of photographing an image at regular intervals using an optical system.
[0038]
The in-focus degree calculation unit 5 can use a so-called high-pass filter that extracts and integrates a high-frequency component for each image captured by the image capturing unit 4.
[0039]
The spectacle wearing determination unit 6 is a subject to be detected when there are a predetermined number or more of pixels having a predetermined luminance or higher due to the influence of reflected light from a frame of the spectacles or the like in the image captured by the image capturing unit 4. The configuration may be such that it is determined that the certifier is wearing glasses, or the input unit (not shown) is connected to the spectacle wear determination unit 6 and a predetermined input is received from the input unit May be configured to determine that the user is wearing glasses. Here, as a predetermined input method, for example, a method of causing various users to easily perform operations such as long press of a predetermined direct key or double press of a start key is practical.
[0040]
The in-focus image determining unit 7 determines that the image is an in-focus image if the in-focus degree calculated by the in-focus level calculating unit 5 is equal to or greater than a predetermined threshold value. It is determined that the image is not a focused image, and the focused image is output.
[0041]
Note that the functions of the in-focus degree calculation unit 5, the spectacle wearing determination unit 6, and the in-focus image determination unit 7 can also be realized by software.
[0042]
As the light irradiation unit 8, for example, a known light emitting diode (LED) that generates near infrared light can be used.
[0043]
The guidance information output unit 10 causes the person to be authenticated to guide the position of the eye 2 of the person to be authenticated to a predetermined position using sound, light, or the like as will be described later.
[0044]
Next, the authentication device 3 of the present invention includes an image capturing device 1 according to the present invention, a focused image storage unit 12 that stores a focused image output from the focused image determination unit 7 of the image capturing device 1, and an in-focus image storage unit 12. Using the image stored in the focal image storage unit 12, the authentication information generation unit 13 that generates an iris code as authentication information by a known method (see, for example, the method described in Patent Document 1), and the storage unit 14 A comparison / collation unit 16 for comparing and collating the stored registration authentication information 15 and the authentication information created by the authentication information creating unit 13, and a result of comparison / collation by the comparison / collation unit 16, that is, either match or mismatch And a display unit 17 for displaying.
[0045]
A known frame memory or the like can be used as the focused image storage unit 12, and a known disk device or memory can be used as the storage unit 14 as appropriate.
[0046]
For the method for creating an iris code from an image in the authentication information creating unit 13 and the method for comparing and collating authentication information with each other in the comparison and collation unit 16, for example, the method described in Patent Document 1 can be used. However, the authentication device 3 of the present invention is not limited to this method, and authentication information can be created and verified using any known method such as pattern matching.
[0047]
Furthermore, a well-known display means, for example, a liquid crystal display, LED, etc. can be used for the display part 17. FIG.
[0048]
Next, each configuration of the authentication device 3 of the present invention is used by being incorporated in, for example, the mobile phone device 20 shown in FIG.
[0049]
Here, the cellular phone device 20 includes a microphone unit 21 and a speaker unit 22 used during a voice call, a key unit which is an input unit for inputting a destination telephone number, inputting text information such as mail, and inputting a key such as a URL. 23. The authentication device 3 according to the embodiment of the present invention is mounted on a known mobile phone device that includes a display unit 17 such as an antenna unit 24 that transmits and receives radio waves, a liquid crystal display, an EL, and an LED. Although the mobile phone device 20 according to the embodiment of the present invention has a configuration in which the upper housing 28 and the lower housing 29 are foldably connected to each other by the hinge portion 27, the present invention is limited in its form. Not what you want.
[0050]
In the mobile phone device 20 according to the embodiment of the present invention, a pair of light beam irradiation units 8 is provided on the lower side of the display unit 17 of the upper housing 28 in FIG. 3, and a hole 25 is provided between the light beam irradiation units 8. A mirror unit 26 is provided, and the optical system of the image capturing unit 4 can be seen through the hole 25. Here, the pair of light beam irradiation units 8 is provided in order to capture an eye image with high contrast and less blur sufficient to create an iris code.
[0051]
As will be described later, the mirror unit 26 is used to guide the position of the eye 2 of the person to be authenticated to a predetermined position.
[0052]
The operation of the authentication device 3 in the embodiment of the present invention as described above will be described in order with reference to the drawings.
[0053]
FIG. 4 is a flowchart showing the operation steps of the authentication device 3 in the embodiment of the present invention.
[0054]
First, when authentication by the authentication device 3 is started by the person to be authenticated operating the key unit 23, the light irradiation control unit 9 causes the light irradiation unit 8 to emit light. Accordingly, the eye 2 of the person to be authenticated is irradiated with near infrared light (S1).
[0055]
Here, the person to be authenticated moves the authentication device 3 to a position where his / her eye 2 is reflected on the mirror part 26 to a position where the iris part of the eye 2 just overlaps the hole 25. As a result, the person to be authenticated can place his / her eye 2 on the optical axis of the optical system of the image photographing unit 4. That is, the position of the eye 2 can be guided so as to be in a positional relationship that can be recognized in the X-axis direction and the Y-axis direction in FIG. Further, the person to be authenticated moves the authentication device 3 so as to approach the Z-axis direction in FIG.
[0056]
Next, the image capturing unit 4 captures an image at regular time intervals, that is, intermittently while the authentication subject moves the authentication device 3 so as to approach the user (S2).
[0057]
The photographed image is sent from the image photographing unit 4 to the in-focus degree calculating unit 5 and the spectacle wearing determining unit 6, and the in-focus degree calculating unit 5 extracts the high frequency component from the image as described above. The degree of focus is calculated (S3).
[0058]
The glasses wear determination unit 6 counts the number of pixels having a predetermined luminance or higher in the sent image, and if the counted number of pixels is equal to or greater than a predetermined threshold, the person to be authenticated wears glasses. (S4). On the other hand, the image is sent to the focused image determination unit 7, and it is determined whether or not it is a focused image as will be described later.
[0059]
When the spectacle wearing determination unit 6 is configured to determine that the subject is wearing spectacles when a predetermined key input is performed from the input unit connected as described above, the step S4 is performed. When the predetermined key input is performed from the input unit, it is determined that the subject wears glasses.
[0060]
The result of determining whether or not the person to be authenticated is wearing glasses is sent to the focused image determination unit 7 in the glasses wearing determination unit 6, and different focused images are determined depending on whether or not glasses are worn. (S5, S6).
[0061]
Next, the details of the focused image determination process in the focused image determination unit 7 of the authentication device 3 of the present invention will be described in detail.
[0062]
FIG. 5 is a diagram for explaining the function of the focused image determination unit 7 of the authentication device 3 according to the embodiment of the present invention. Here, as an example, a case where the person to be authenticated holds the authentication apparatus 3 in his hand and performs authentication while approaching the authentication apparatus 3 is shown.
[0063]
The graph shown in FIG. 5 is a graph showing the relationship of the degree of focus with respect to the time when the image was taken (hereinafter referred to as the focus degree curve). In the graph shown in FIG. 5, the vertical axis represents the degree of focus of an image photographed at a predetermined time interval while bringing the device close to the focus degree calculation unit 5 for each image, and the horizontal axis represents the image photographed. It's time. Here, since the person to be authenticated performs photographing at a predetermined time interval while bringing the authentication device 3 closer, the horizontal axis indicates the photographing distance, and the photographing distance increases in the right direction (the direction in which time elapses). Get closer.
[0064]
As shown in FIG. 5, first, when the person to be authenticated does not wear glasses, that is, in the case of the naked eye, the degree of focus gradually increases as the person to be authenticated moves closer to the authentication device 3 as shown by the broken line. The maximum 41 is shown in a state where the iris is in focus (focused), and decreases as the iris approaches further. Thus, in the state of the naked eye where the subject is not wearing glasses, the number of values that becomes the maximum 41 indicated by the degree of focus with the change in distance is one.
[0065]
In such a case, the in-focus image determination unit 7 determines that the image obtained with the in-focus degree P1 that has reached the predetermined threshold value TH for the first time on the in-focus level curve in FIG. 5 is the in-focus image. (S6).
[0066]
An example of an image determined as a focused image in this way is shown in FIG. As shown in FIG. 6A, in the focused image 51 with the naked eye, the reflection image 30 on the cornea of the light irradiation unit 8 is reflected in the pupil portion and does not cover the iris region. Therefore, a good iris image can be taken.
[0067]
When the person to be authenticated is naked eye, the in-focus image determination unit 7 captures images taken within the range of the threshold TH in FIG. 5, that is, between the in-focus level P1 and the in-focus level P2. The focused image 51 may be used. Further, in the configuration in which the person to be authenticated takes a picture while approaching the authentication device 3, the eye-focused image 51 is more quickly determined when the image shot at the focus P <b> 1 is the eye-focused image 51. be able to.
[0068]
As described above, when the spectacle wear determination unit 6 determines that the person to be authenticated does not wear spectacles, the focused image determination unit 7 matches the image captured at the above-described focus degree P1. A focused image 51 is assumed. In the case where the person to be authenticated is configured to take an image while moving away from the authentication device 3, the in-focus image 51 can be determined more quickly if the image taken at the in-focus degree P <b> 2 is the in-focus image 51. It goes without saying that it can be done. In such a case, the focused image determination unit 7 sets the image captured at the focus level P2 as the focused image 51.
[0069]
On the other hand, as shown by a solid line in FIG. 5, when the person to be authenticated wears glasses, when the person to be authenticated brings the authentication device 3 closer, the degree of focus gradually increases, and the first When the value exceeds the minimum 42 and then exceeds the minimum 44, the value increases again, indicating the second maximum 43, and then decreases. The first maximum 42 that appears as the distance is reduced is a maximum that indicates that the frame or lens surface of the glasses is in focus, and the second maximum 43 that appears next is a peak that appears when the iris is focused.
[0070]
Therefore, in the above-described step S4, when a signal indicating that the subject is wearing glasses is sent from the glasses wearing determination unit 6 to the focused image determining unit 7, the focused image determining unit 7 is a solid line focus degree curve in FIG. 5, and among the images having a focus degree equal to or greater than a predetermined threshold TH, the focus degree on the right side, that is, the side closer to the distance in the second maximum 43. It is determined that the image corresponding to P5 is a focused image (S5).
[0071]
The reason for this will be described. 6B to 6D are examples of photographed eye images.
[0072]
FIG. 6B is an image 52 corresponding to the focus degree P3 in which the focus degree exceeds the predetermined threshold TH on the side where the distance of the first maximum 42 in FIG. 5 is far (the left side in FIG. 5). As shown in FIG. 6B, the image 52 has a high degree of focus because it is in focus (focused) on the lens surface of the glasses, the frame, etc., and is not in focus on the iris. Is not right. Further, in the image 52, the reflection 31 on the lens surface of the light irradiation unit 8 is applied to the periphery of the iris, and it is difficult to acquire an iris image due to this influence.
[0073]
Next, FIG. 6C is an image 53 corresponding to the focus degree P4 at which the focus degree exceeds the predetermined threshold TH on the far side (left side in FIG. 5) of the second maximum 43 in FIG. In the image 53, although the iris is in focus, the reflection 31 on the lens surface of the light irradiation unit 8 is still in the vicinity of the iris, and it is difficult to obtain a good image of the iris due to this influence.
[0074]
Further, FIG. 6D shows that the person to be authenticated brings the authentication device 3 closer and the degree of focus exceeds the threshold TH on the side closer to the second maximum 43 in FIG. 5 (right side in FIG. 5). It is the image 54 corresponding to the degree of focus P5. In the image 54, the iris is in focus and the reflection 31 of the light irradiation unit 8 covers the white-eye area outside the iris area.
[0075]
Such an image 54 corresponding to the degree of focus P5 in which the degree of focus on the near side (right side in FIG. 5) of the second maximum 43 in FIG. An iris image can be taken. It should be noted that the image 54 corresponding to the above-described focus degree P5 is preferably used as the in-focus image in any of the configurations in which the person to be authenticated performs shooting while approaching the authentication device 3 or performs shooting while moving away. .
[0076]
Returning to FIG. 4, when the focused image determination in steps S5 and S6 described above is performed, while the focused image is not obtained, the process returns to step S2 to further shoot an image. On the other hand, when a focused image is obtained, the focused image is sent from the focused image determination unit 7 to the focused image storage unit 12 (S7).
[0077]
The in-focus image stored in the in-focus image storage unit 12 is sent to the authentication information creation unit 13, and the registration authentication information 15 stored in the storage unit 14 in advance and the authentication information created in the authentication information creation unit 13 Is compared and authenticated by the comparison / collation unit 16, and the result is displayed on the display unit 17 (S8).
[0078]
In addition, about the authentication process in this step S8, various well-known methods other than the method described in patent document 1 can be used, for example.
[0079]
The light beam irradiation control unit 9 is configured to increase the intensity of the light beam applied to the light beam irradiation unit when the focus level calculated by the focus level calculation unit 5 exceeds a predetermined threshold LTH. May be. With such a configuration, when the in-focus degree is equal to or less than the predetermined threshold value LTH, a light beam having a relatively low intensity is irradiated, so that the power consumption of the entire apparatus can be reduced.
[0080]
Moreover, even if the guidance information output control unit 11 controls the guidance information output unit 10 to output different guidance information in accordance with the change in the degree of focus calculated by the focus degree calculation unit 5. Good. For example, when the guidance information is sound, a configuration in which the person to be authenticated can easily guide his / her distance can be realized by increasing or decreasing the frequency of the guidance sound as the degree of focus increases.
[0081]
Note that the image capturing device 1 according to the embodiment of the present invention has been described using the configuration mounted inside the authentication device 3, but the image capturing device 1 of the present invention is not limited to this, and the image capturing is performed. Needless to say, the device may be used alone or mounted on another information device or the like.
[0082]
Furthermore, in the image photographing device 1 according to the embodiment of the present invention, the configuration in which the person to be authenticated performs photographing by moving the image photographing device 1 by himself / herself is shown, but the image photographing device 1 of the present invention is not limited to this. Needless to say, the image photographing apparatus of the present invention also includes a configuration in which the image photographing apparatus 1 is moved relative to the subject by a known moving means.
[0083]
It should be noted that the image photographing apparatus 1 according to the embodiment of the present invention can obtain a good eye image even when the subject is wearing glasses. Therefore, in the authentication device 3 according to the embodiment of the present invention, the authentication information has been described as an iris code created from an eye image. However, the authentication device of the present invention is not limited to this, for example, blood vessels in the fundus It goes without saying that any authentication information created from a human eye image such as a pattern can be used.
[0084]
【The invention's effect】
As described above, according to the present invention, the hand-held type authentication device includes the spectacle wearing determination unit, so that it can be determined whether or not the subject is wearing spectacles. Furthermore, when it is determined that the subject wears spectacles in the spectacle wearing determination unit, the degree of focus is equal to or greater than a predetermined threshold and the image with the shortest shooting distance is determined as the focused image. Image photographing apparatus capable of reducing adverse effect of reflected image on lens surface of eyeglass on eye image, particularly iris image, and obtaining focused image suitable for authentication having good iris pattern, and authentication using the same Equipment can be provided.
[Brief description of the drawings]
FIG. 1 is a block diagram illustrating a configuration of an image capturing device and an authentication device according to an embodiment of the present invention.
FIG. 2 is a diagram for explaining how to use the authentication device according to the embodiment of the present invention;
FIG. 3 is a diagram showing an external appearance of a mobile phone device equipped with an authentication device according to an embodiment of the present invention.
FIG. 4 is a flowchart showing operation steps of the authentication device in the embodiment of the present invention.
FIG. 5 is a diagram for explaining a function of a focused image determination unit of the authentication device according to the embodiment of the present invention;
6A is a diagram illustrating an example of an image determined to be a focused image in the embodiment of the present invention. FIGS. 6B to 6D are actually taken in the embodiment of the present invention. The figure which shows an example of an eye image
[Explanation of symbols]
1 Image capture device
2 Eyes of the person to be authenticated
3 Authentication device
4 Image shooting unit
5 Degree of focus calculation unit
6 Glasses wear determination part
7 Focused image determination unit
8 Light irradiation part
9 Light irradiation control unit
10 Guidance information output section
11 Guide information output controller
12 Focused image storage unit
13 Authentication information generator
14 Storage unit
15 Registration Authentication Information
16 Comparison verification part
17 Display
20 Mobile phone device
21 Microphone part
22 Speaker section
23 Key part
24 Antenna section
25 holes
26 mirror part
27 Hinge
28 Upper case
29 Lower housing
30 Reflected image
31 Reflection
41 maximum
42 First maximum
43 Second maximum
44 Minimal
51 Focused image
52-54 images

Claims (11)

An image capturing unit that captures an image of a subject at a position where the shooting distance differs from each other;
A degree-of-focus calculator that calculates the degree of focus of each of the plurality of images captured by the image capturing unit;
A spectacle wearing determination unit for determining whether the subject is wearing spectacles;
When the spectacle wearing determination unit determines that the subject is wearing spectacles, among the plurality of images, an image whose focus is equal to or greater than a predetermined threshold at a position closest to the subject is viewed An in-focus image determining unit that determines that the image is an in-focus image ;
A light irradiation unit for irradiating the subject with light,
The light irradiation control unit increases the intensity of light irradiated to the light beam irradiation unit when the focus level exceeds a predetermined threshold in the focus level calculation unit. Shooting device. An image capturing unit that captures an image of a subject at a position where the shooting distance differs from each other;
A degree-of-focus calculator that calculates the degree of focus of each of the plurality of images captured by the image capturing unit;
A spectacle wearing determination unit for determining whether the subject is wearing spectacles;
When the subject wear determination unit determines that the subject is wearing eyeglasses, the relationship between the shooting distance and the degree of focus of the image among the plurality of images increases as the subject approaches. When the degree of focus changes to show the first maximum and then changes to show the second maximum, the degree of focus is equal to or greater than a predetermined threshold, and the shooting distance is the second maximum. An in-focus image determining unit that determines that an image closer than the shooting distance corresponding to is an in-focus image of the eye ;
A light irradiation unit for irradiating the subject with light,
The light irradiation control unit increases the intensity of light irradiated to the light beam irradiation unit when the focus level exceeds a predetermined threshold in the focus level calculation unit. Shooting device.   When it is determined in the glasses wearing determination unit that the subject does not wear glasses, the in-focus image determining unit has the focus degree at a position farthest from the subject among the plurality of images. The image capturing apparatus according to claim 1, wherein an image having a predetermined threshold value or more is determined to be an in-focus image of the eye.   The glasses wearing determination unit determines that the subject is wearing glasses when there are a predetermined number or more of pixels having a predetermined luminance or higher among images captured by the image capturing unit. The image photographing device according to any one of claims 1 to 3.   An input unit connected to the glasses wearing determination unit, and when a predetermined input is made to the input unit, the glasses wearing determination unit determines that the subject is wearing glasses; The image photographing device according to any one of claims 1 to 3. With respect to the subject, any of the object distance from claim 1, characterized in that with a guidance information output unit for outputting the guidance information to guide a distance as obtained with the focusing image to claim 5 The image capturing device according to claim 1. Guidance information output control for causing the guidance information output unit to modulate and output the frequency of the voice information based on the degree of focus calculated by the focus degree calculation unit, wherein the guidance information is information by voice. The image photographing device according to claim 6 , further comprising a unit. The image photographing apparatus according to claim 7 , wherein the irradiation light irradiated from the light beam irradiation unit is near infrared light. The image photographing device according to any one of claims 1 to 8 ,
A focused image storage unit for storing the focused image determined by the focused image determination unit;
An authentication information creating unit that creates authentication information from the focused image stored in the focused image storage unit;
An authentication apparatus comprising: a comparison / collation unit that compares and collates pre-registered registration authentication information and the authentication information created by the authentication information creation unit. The authentication apparatus according to claim 9 , wherein the authentication information creating unit creates the authentication information by encoding an iris image obtained from the image of the subject. An image capturing step for capturing images of the subject at different shooting distances;
  A degree-of-focus calculation step of calculating the degree of focus of each of the plurality of images photographed in the image photographing step;
  Glasses wearing determination step for determining whether or not the subject is wearing glasses;
  When it is determined in the spectacle wearing determination step that the subject wears spectacles, an image of which the in-focus level is equal to or greater than a predetermined threshold at the position closest to the subject among the plurality of images. A focused image determination step for determining that the image is a focused image of
  A light beam irradiation step for irradiating the subject with a light beam,
  The light irradiation control step increases the intensity of light irradiated to the light beam irradiation step when the focus level exceeds a predetermined threshold in the focus level calculation step. Shooting method.

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