JP2003037708A - Image authentication device - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To appropriately notify and transmit an operation state of an image authentication apparatus, such as an authentication processing result, to a person to be authenticated while suppressing an increase in apparatus scale and an increase in product cost. Provided is an image authentication device having a function capable of performing the function. SOLUTION: The image authentication apparatus is roughly divided into a sensor device (image reading means) SEN for reading a two-dimensional image (corresponding to unique information of a person to be authenticated; for example, a fingerprint) of a predetermined subject SUB, and a sensor device. A light source unit LGT disposed on the back side of the SEN, an image reading operation in the sensor device SEN, a light emitting state in the light source unit LGT,
And an operation control unit CON that controls identification and authentication processing of a read image in an authentication processing unit ATS described below, and a two-dimensional image read by the sensor device SEN,
An authentication processing unit (image identification unit) ATS for identifying and authenticating the subject SUB (or the person to be authenticated) ATS.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image authentication apparatus, and more particularly to an image authentication apparatus which reads a two-dimensional image of a subject such as a fingerprint and makes an authentication decision on the subject based on the two-dimensional image.

[0002]

2. Description of the Related Art In recent years, there has been a tendency for illegal invasion of facilities and buildings such as laboratories and theft of information from information devices such as personal computers to increase, and only for a preset specific person. The spread of security devices that allow entry and use is required. Also, in fields such as electronic commerce, which is expected to spread rapidly in the future, it is required to establish a technique for authenticating a person as an essential technique.

Conventionally, as means for authenticating a specific person, for example, information specific to the authentication target person (image information etc.) such as a fingerprint is read, and the authentication target person is identified based on the specific information. There is known a person authentication device (image authentication device) that authenticates with a user. Here, as a technique for reading unique information such as a fingerprint that has been conventionally applied to an image authentication device, for example, an electrostatic capacitance detection type or optical type image reading means is known.

In the electrostatic capacitance detection type image reading means, a plurality of electrodes are arranged in a matrix on a detection surface on which a subject is placed via a dielectric film, and a finger is placed on a convex portion of a fingerprint. And change in capacitance between the recess and the electrode (difference)
Image pattern (fingerprint) of the subject by detecting
Is to read. Regarding such an image reading means, for example, JP-A-4-231803 and JP-A-2
It is described in detail in Japanese Patent Publication No. 001-67460.

On the other hand, in the optical image reading means, the photosensors are arranged in a matrix on the detection surface via a protective film, and the photosensors are arranged on the back side of the sensor device (the side opposite to the side on which the finger is placed). The light and dark information corresponding to the fingerprint is read by detecting the amount of electric charge accumulated according to the reflected light of the predetermined irradiation light from the backlight.
An example of the configuration of the optical image reading means will be described later in detail. In addition, as a technique for authenticating unique information such as a fingerprint, for example, by comparing the read unique information (fingerprint) with characteristic points in pre-registered reference information,
There is known a method of authenticating whether or not the person to be authenticated is a person who is permitted to enter the facility or use the information device.

[0006]

By the way, in the conventional image authentication apparatus as described above, in order to notify the person to be authenticated of the result of the authentication processing based on the read unique information, a display apparatus, an audio apparatus, or the like is used. It is common to employ a configuration in which visual and auditory communication is used. However, when the configuration including the display device and the audio device separately from the image authentication device is applied as described above, the device scale is increased and the product cost is increased. There is a problem in that the application of the image authentication device (particularly, the fingerprint authentication device) to a mobile device such as an information terminal (PDA) is hindered.

In view of such problems, the present invention suppresses the increase in the size of the device and the increase in the product cost, and determines the operation state of the image authentication device such as the result of the authentication process as the authentication target person. An object of the present invention is to provide an image authentication device having a function capable of accurately notifying and transmitting.

[0008]

An image authentication apparatus according to the present invention comprises image reading means for reading a two-dimensional image of a subject placed on a predetermined detection surface, and based on the two-dimensional image,
An image authentication device including an image identification unit that performs authentication determination of the subject, the image authentication device having a light source unit that emits light in at least two different colors and irradiates the detection surface,
The light source unit emits light in a predetermined color according to a predetermined operation state of the image authentication device.

That is, the detection surface on which the subject is placed emits light of a predetermined color according to various operating states of the image authentication apparatus. As a result, the person to be authenticated who mounts the subject can visually recognize the operation state of the image authentication device by the emission color of the detection surface, and thus can accurately notify and transmit the operation state. Since it is not necessary to provide a configuration such as a display device separately from the image authentication device, it is possible to favorably suppress an increase in device size and an increase in product cost.

Here, the operation state of the image authentication device means, for example, whether the position of the subject placed on the detection surface is normal, whether the image reading operation for reading a two-dimensional image of the subject is in progress, or , The result of the authentication determination of the read two-dimensional image of the subject, and the like, the emission color of the detection surface is controlled to be different depending on the suitability. As a result, the authentication target person determines whether or not the subject is placed at a normal position on the detection surface before the operation of reading the two-dimensional image of the subject, and the reading operation of the two-dimensional image is executed. Whether or not, or whether or not the authentication target person has been authenticated based on the read two-dimensional image, the state and the result can be accurately recognized visually by the emission color of the detection surface.

Further, in the above image authentication apparatus, the light source section may be composed of a single light emitting device capable of emitting light of two or more different colors, or each light emitting color may be individually provided. It may be composed of a light emitting device. According to this, in the former,
Since the detection surface can emit light in different colors with a single light emitting device, it is possible to further suppress the increase in the scale of the device. In the latter case, by emitting a plurality of light emitting devices with a single color, respectively. Since the detection surface can be made to emit light in different colors, it is possible to easily control the light emission of the light emitting device.

In this case, by setting red and blue, for example, as the emission colors of the detection surface emitted by the light source unit, in the case of the normal state or the normal operation depending on the suitability of the operation state of the image authentication device. Emits blue light,
Since red light emission can be performed in an abnormal state or abnormal operation, the authentication target person can intuitively visually recognize the operation state of the image authentication device by the emission color of the detection surface.

In the above image authentication device, for example, a light emitting diode element or an electroluminescent element, or a combination of a light emitting diode element and an electroluminescent element is favorably applied as a light emitting device constituting a light source section. can do. According to this, compared with the case where a fluorescent tube or the like is applied as a light emitting device, the device scale including peripheral circuits can be significantly reduced in size and weight, and power consumption can be reduced. It is possible to realize an image authentication device that is more suitable for the specifications of small size, light weight, and low power consumption required when applied to the above.

Further, in the above-mentioned image authentication device, the image reading means detects the change in electrostatic capacitance between the subject and the electrodes arranged two-dimensionally on the detection surface side to detect the two-dimensional subject. An electrostatic capacitance detection type image reading method for reading an image may be applied, and the amount of reflected light with respect to the irradiation light applied to the subject placed on the detection surface is set to 2 on the detection surface side. An optical image reading method for reading a two-dimensional image of a subject by detecting with a two-dimensionally arranged photo sensor may be applied. According to this, the configuration of the present invention is favorably applied to an existing image reading unit applied as an image authentication device (particularly, a fingerprint authentication device) and an image reading unit that is being considered for practical use in the future. can do.

Here, a backlight provided in an optical image reading means is applied (combined) as the light source section, and a light emitting device constituting the backlight is formed according to the operation state of the image authentication apparatus. The light may be emitted in different emission colors. Thus, the detection surface can be made to emit light of a predetermined color in accordance with the operation state of the image authentication device, without changing the configuration of the optical image reading means and by only simple light emission control.

In the image authentication device, the photo sensor forming the image reading means includes a source electrode and a drain electrode formed with a channel region made of a semiconductor layer sandwiched therebetween, and at least above and below the channel region. A first gate electrode and a second gate electrode each formed through an insulating film, a reset pulse is applied to the first gate electrode to initialize the photo sensor, and a precharge pulse is applied to the drain electrode. And then applying a read pulse to the second gate electrode, the voltage corresponding to the charge accumulated in the channel region is output as the output voltage during the charge accumulation period from the end of initialization to the application of the read pulse. However, the image reading means observes the difference between the signal voltage related to the precharge pulse and the output voltage as the signal component. It may be a shall.

That is, the photosensor applies a reset pulse to the top gate electrode (first gate electrode) and a read pulse to the bottom gate electrode (second gate electrode) at a predetermined timing, It is configured by a so-called double-gate type photosensor that outputs a voltage corresponding to the charges accumulated in the channel region during the charge accumulation period. As a result, the photo sensor that constitutes the image reading means can be made thinner and smaller,
The density of the read pixels is increased, and the two-dimensional image of the subject can be read as a high-definition image.
It is possible to further improve the accuracy of the authentication determination of the authentication target person based on the three-dimensional image.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of an image authentication apparatus according to the present invention will be described in detail below. <First Embodiment> FIG. 1 is a block diagram showing the overall configuration of a first embodiment of an image authentication apparatus according to the present invention.

As shown in FIG. 1, the image authentication apparatus according to the present embodiment is roughly classified into a sensor for reading a two-dimensional image of a predetermined subject SUB (corresponding to the unique information of the person to be authenticated; for example, a fingerprint). Device (image reading means) SEN
And a light source unit LGT arranged on the back side of the sensor device SEN, an image reading operation in the sensor device SEN, a light emitting state in the light source unit LGT, and an identification and authentication process of a read image in an authentication processing unit ATS described later. An operation control unit CON and an authentication processing unit (image identification means) ATS that identifies and authenticates the subject SUB (or the person to be authenticated) based on the two-dimensional image read by the sensor device SEN. Have a configuration.

Each configuration will be specifically described below. The sensor device SEN reads a two-dimensional image of the subject SUB such as a finger placed on the detection surface provided on the one surface side, and is, for example, the electrostatic capacitance detection type or optical type image as described above. The reading means can be applied well. Here, the sensor device SEN uses light emitted from the light source unit LGT arranged on the back side (other surface side) of the sensor device SEN to notify the operating state of the image authentication device, as described later. Sensor device SE
In order that at least a partial region or the entire region of the detection surface provided on the one surface side of N emits light with a predetermined emission color,
It is desirable that each cross-sectional structure of the sensor device SEN be made of a material having translucency. The specific configuration of the sensor device SEN applicable to the present invention will be described later in detail.

FIG. 2 is a schematic configuration diagram showing a configuration example of a light source unit applied to the image authentication apparatus according to this embodiment.
FIG. 3 is a spectrum distribution diagram showing a spectrum characteristic of light emitted from the light source unit applied to the image authentication apparatus according to the present embodiment. Here, the spectral distribution shown in FIG. 3 shows an outline of the spectral characteristics of light of each color, and is not an actual measurement value. The light source unit LGT is shown in FIG.
As shown in (b), a plurality of light emitting diodes (L
ED; a light emitting device) and a detection surface Fd on the upper surface of the sensor device SEN described above are configured to have a planar spread, and the light emitting unit 1 is arranged on one side surface side. And a light guide plate 2.

The light emitting section 1 emits a plurality of light emitting diodes, for example, red light, capable of emitting light of different colors which can be easily visually recognized by humans (the difference in light emission color can be easily visually recognized). Light emitting diode (red LED) LDr and light emitting diode (blue LED) LD emitting blue light
b is arranged along one side surface of the light guide plate 2. That is, the light emission colors of the respective light emitting diodes LDr and LDb are, specifically, as shown in FIG. 3, light of different colors (for example, approximately 600 to 700 nm and approximately light having a spectral distribution in which peak wavelengths do not overlap with each other). (Red light and blue light showing spectral distributions Sr, Sb having peaks in the respective wavelength bands of 430 to 480 nm). Here, as the blue LED,
For example, a well-known light emitting diode made of a gallium nitride-based compound semiconductor can be favorably applied. Although not shown, a reflector (reflection plate) for reflecting the light emitted from each of the light emitting diodes LDr, LDb to one side surface direction of the light guide plate 2 to the back side of the light emitting diodes LDr, LDb. ) May be provided.

The light guide plate 2 is made of a transparent synthetic resin such as glass or acrylic, and is used as a sensor device SE.
In order to diffuse the light emitted from the light guide plate 2 evenly over almost the entire one end face side (the front face side in FIG. 2A and the upper face side in FIG. 2B) facing N, the surface emission is performed. 2 is provided, and the light guide plate is provided over substantially the entire area of the other surface side (the back surface side in FIG. 2A and the bottom surface side in FIG. 2B) facing the one end surface. A reflection plate 4 is provided to reflect the light scattered and diffused inside 2 to the one end face side.

In such a light source unit LGT, as shown in FIG.
As shown in (b), each light emitting diode LD of the light emitting unit 1
The light (red light, blue light) emitted from r and LDb is individually incident from one side surface side of the light guide plate 2 and is emitted to the sensor device SEN from one end surface side, and is made of a translucent material. After passing through the sensor device SEN, the light is emitted from the detection surface Fd formed on the upper surface of the sensor device SEN.

The authentication processing unit ATS uses the sensor device SE.
By comparing the two-dimensional image read by N with the two-dimensional image of the subject SUB that has been registered in advance for the person who is permitted to authenticate, the subject SUB is identified, and the authentication determination of the person to be authenticated is performed. To do. Then, the result of the authentication determination is output to the operation control unit CON and used as a control signal when setting the light emission state in the light source unit LGT. Here, the comparison processing of the two-dimensional image includes the comparison of the image patterns in the entire read two-dimensional image and the feature points included in the image pattern, for example, the comparison of fingerprint images in the comparison processing of the fingerprint images. Differences between two-dimensional images (fingerprints) can be determined by comparing the positions and presence / absence of line end points and branch points.

Next, the control operation of the image authentication apparatus according to this embodiment will be described with reference to the drawings. Here, the series of control operations described below is performed by the operation control unit C.
It is executed by turning on. FIG. 4 is a light emission state diagram of the light source unit showing an example of the control operation in the image authentication apparatus according to the present embodiment. Here, for convenience of illustration, different hatching is used for convenience in order to clarify the difference in emission color.

In the image reading / authentication apparatus having the above-mentioned structure, the control operations of roughly reading the two-dimensional image of the object, the identification / authentication processing of the read image, and the notification of the authentication result are sequentially executed. First, in the reading operation of the two-dimensional image of the subject, as shown in FIG.
For example, with the subject SUB such as a finger placed on the detection surface Fd on the upper surface of the sensor device SEN, the electrostatic capacitance detection type or optical type image reading method as described above is applied to correspond to the detection surface Fd. Is performed by measuring a detection signal (change in capacitance or accumulated charge amount) corresponding to the image pattern of the finger (convex portion and concave portion of the fingerprint) by two-dimensionally arranged detection electrodes or photosensors. . Here, as a light source used for an optical two-dimensional image reading operation,
As shown in FIG. 4B, a light source used for an authentication result notification operation described later, for example, a predetermined light emitting diode (for example, red LED; LDr) of the light source unit LGT,
The setting may be controlled so that a part or the whole of the detection surface Fd on which the finger is placed emits light in a predetermined color (red emission).

Next, in the identification and authentication processing of the read image, the two-dimensional image data read by the above-described two-dimensional image reading operation is taken into the authentication processing section, and the two-dimensional image data and the authentication processing section are preliminarily stored. By comparing the registered two-dimensional image data of the subject SUB of the person authorized for authentication, the subject SUB is identified and it is determined whether the person to be authenticated is an authorized person. The result of this determination is output to the operation control unit CON. In addition,
During this operation, for example, the light emitting diode (for example, the blue LED; LDb) in the light source unit LGT is stopped to emit light so that the authentication target person recognizes at least that the reading operation of the two-dimensional image is completed. hand,
The detection surface Fd may be set and controlled so that it does not emit light.

Then, the operation of notifying the authentication result is performed by the light source unit as shown in FIG. 4C when the person to be authenticated is authenticated based on the result of the authentication judgment in the authentication processing unit ATS. A predetermined light emitting diode (for example, blue LED; LDb) of the LGT is controlled to emit light of a predetermined color (blue light) to cause the detection surface Fd to emit light of that color. Then, the fact that the authentication is permitted (the result of the authentication judgment) is notified.

On the other hand, in the authentication processing section, when the person to be authenticated is not permitted to be authenticated (authentication is rejected),
As shown in FIG. 4B, a predetermined light emitting diode (for example, a red LED;
LDr) is controlled to emit light of a predetermined color (red light) so that the detection surface Fd emits light of that color, so that the person to be authenticated has been denied authentication (the result of the authentication determination). ) Is notified.

As described above, according to the image authentication apparatus of this embodiment, at least the result of the authentication determination (the operation state of the image authentication apparatus) can be visually notified and transmitted by the emission color of the detection surface. Therefore, the person to be authenticated can accurately and quickly recognize the operation state. In particular,
In this case, when the authentication is permitted, the detection surface is generally made to emit light by the blue light used as the permission color, the safety color, and the normal color. In addition, since it is possible to notify the person to be authenticated of the result of the authentication judgment by causing the detection surface to emit light with red light used as a refusal color, a dangerous color, or an abnormal color, the authentication target person can It is possible to intuitively recognize the result of the authentication determination by the emission color. Further, as described above, when the detection surface is made to emit light during the reading operation of the two-dimensional image, in addition to the above blue light emission, the red LED and the blue LED are simultaneously controlled to emit red light and blue light. The detection surface may be made to emit light by the combined light of, or a light emitting diode that emits light of a color other than red or blue (for example, yellow light) is further provided, and detection is performed by the monochromatic light or the combined light. The surface may be made to emit light of a desired color.

It should be noted that, as the luminescent color that allows the result of the authentication judgment to be intuitively recognized, green or yellow light can be applied in addition to the above-mentioned red and blue. However, the spectral distributions of the green light and the yellow light are between the peak wavelengths of the spectral distributions Sr and Sb of the red light and the blue light shown in the spectral distribution diagram of FIG. Also in the degree coordinate diagram, since the coordinate areas of yellow light and green light or red light are close,
It may be difficult to recognize a color change between yellow light and green light or red light. Therefore, for example, blue light and yellow light, or green light and red light, or red light, blue light,
Unlike the combination of white light, which is a composite color of green light, and red light, blue light, or green light, the peak wavelength and chromaticity coordinates of the spectral distribution do not approximate each other, and it is possible to easily distinguish visually. By applying the combination of the emission colors, it is possible to satisfactorily notify and convey the operating state of the image authentication device through the eyes.

Further, according to such an image authentication device,
By using the detection surface (sensor device) that is an essential component of the image authentication device, by radiating light of different colors from the light source unit arranged on the back side of the sensor device to cause the detection surface to emit a desired color. Since various operating states can be notified and transmitted, it is not necessary to provide a configuration such as a display device separately from the image authentication device, and it is possible to favorably suppress an increase in device scale and an increase in product cost. it can. Furthermore, in this case, by applying a light emitting diode as a light emitting device that constitutes the light source unit, it is possible to significantly reduce the size of the device including peripheral circuits, as compared with a configuration in which a fluorescent tube or the like is applied. Since it is possible to realize a light source unit having high brightness and excellent power saving characteristics, the image authentication device according to the present invention (particularly, the fingerprint authentication device) is favorably mounted on a portable device such as a laptop computer or a mobile phone. be able to.

Next, another configuration example of the light source unit applied to the image authentication apparatus according to this embodiment will be described with reference to the drawings. FIG. 5 is a schematic configuration diagram showing another configuration example of the light source unit applied to the image authentication apparatus according to the present embodiment,
FIG. 6 is a schematic configuration diagram showing still another configuration example of the light source unit applied to the image authentication apparatus according to the present embodiment.

In the above embodiment, the light source unit LG
As shown in FIG. 2, a plurality of monochromatic (red and blue) light emitting diodes LDr and LDb that emit different colors are shown as T.
However, the present invention is not limited to this. That is, as another configuration of the light source unit LGT applied to the present embodiment, as shown in FIGS. 5A and 5B, a single light emitting device capable of emitting light of two or more different colors, for example, As shown in FIG. 5C, a configuration is provided in which the light emitting section 1 is provided with only a single light emitting diode LDx whose peak wavelength in the spectral distribution Sx of emitted light changes by controlling the applied current or the like. The light emitting state is controlled so as to change the color of the light emitted from the light emitting diode LDx according to the operating state of the image authentication device as described above. Note that, in FIGS. 5A and 5B, for convenience of illustration, different hatching is used for convenience in order to clarify the difference in emission color.

As a result, light of an arbitrary different color (for example, a single light emitting device (light emitting diode LDx)) (for example,
Since the detection surface Fd can be made to emit light of a desired color by radiating red light and blue light having the spectral distributions Sr and Sb, the size of the entire image authentication device including the light emitting unit 1 (light source unit LGT) can be increased, The power consumption can be further suppressed, and the application to mobile devices and the like can be further promoted.

Further, the light source unit LG applied to this embodiment
As another configuration of T, for example, as shown in FIG.
As shown in (b), different colors (for example, in the spectral distribution chart shown in FIG. 3, the spectral distribution Sr,
A plurality of stripe-shaped organic or inorganic electroluminescent elements (hereinafter abbreviated as "EL elements") capable of emitting Sb-containing red light and blue light); for example, red EL element and blue EL element) ELr, ELb has a configuration in which it is arranged so as to have a two-dimensional spread corresponding to the detection surface Fd of the sensor device SEN, and the EL elements ELr, EL of the respective colors are provided according to the operating state of the image authentication device described above.
The drive state of b is controlled to change the emission color. In addition,
In FIG. 6A, for convenience of illustration, only the red EL element ELr is shown by hatching.

Here, the EL elements ELr and ELb are shown in FIG.
As shown in (b), a transparent substrate (EL substrate) 31 is provided.
An anode electrode 32 formed of a transparent electrode such as ITO and formed in a stripe shape, and EL layers 33r and 33b containing a light emitting material of a predetermined emission color are sequentially stacked on the anode electrode 32 and the EL layer 33r. , 33b, the cathode electrode layer 34 is laminated on the entire surface.

Then, these EL elements ELr, ELb
In the same manner as in the above-described embodiment, the compound composition of the EL layers 33r and 33b is appropriately set so that the red light and the blue light having the spectral distributions Sr and Sb shown in FIG. 3 can be emitted. Specifically, when an organic EL element is applied, the light emitting material for emitting red light and blue light is a polymer having a conjugated double bond, such as polyphenylene vinylene derivative and polyfluorene. The derivative can be applied well. As a result, an EL element that is thin, has high brightness, and has high power saving characteristics can be applied as a light emitting device, and light of different colors can be emitted to cause the detection surface to emit light of a desired color. It is possible to further reduce the size and power consumption of the entire image authentication device including the unit 1 (light source unit LGT), and further promote application to portable devices and the like.

The light source unit applied to this embodiment is
In addition to the configuration in which only one of the above-described light emitting diode or EL element is applied, the configuration in which the light emitting diode shown in FIG. 2 or 5 is applied (in this case, is provided on the other surface side of the light guide plate). The configuration in which the EL element shown in FIG. 6 is applied is arranged on the back side of (the configuration in which the reflection plate is removed is applied), and the emission color from the light emitting diode and E
The emission colors from the L elements may be used alone or may be combined and emitted to the sensor device so that the detection surface emits light of a desired emission color.

<Second Embodiment> Next, a second embodiment of the image authentication apparatus according to the present invention will be described with reference to the drawings. FIG. 7 is a block diagram showing the overall configuration of the second embodiment of the image authentication device according to the present invention, and FIG. 8 is a schematic configuration diagram showing a configuration example of the image authentication device according to the present embodiment. Here, the same components as those in the above-described embodiment are designated by the same reference numerals, and the description thereof will be simplified or omitted.

As shown in FIG. 7, the image authentication apparatus according to this embodiment has the same configuration (sensor device SEN, light source unit LGT, operation control unit CON, authentication processing unit ATS) as that of the above-described embodiment, It has a configuration in which a plurality of position detection sensors (position detection means) LSN for detecting the position of the subject SUB placed on the detection surface Fd of the sensor device SEN are provided. Here, since the sensor device SEN and the authentication processing unit ATS have the same configurations and functions as those of the above-described embodiment, the description thereof will be omitted.

The light source unit LGT applied to this embodiment is
As shown in FIGS. 8A and 8B, a configuration including a light emitting unit 1 including a plurality of light emitting diodes LDr, LDb, and LDy capable of emitting different colors, for example, red light, blue light, and yellow light, respectively. have. In addition, a plurality of position detection sensors L
As shown in FIG. 8A, the SN is the sensor device SE
It is arranged on the detection surface Fd side of the upper surface of N and in the peripheral area of the reading area AR of the two-dimensional image of the subject SUB. Here, the position detection sensor LSN is specifically, the subject (finger) over substantially the entire reading area AR (detection surface Fd).
In order to detect the state where the SUBs are evenly placed (normal placement state), for example, three locations are arranged at arbitrary positions in the three side directions of the reading area AR.

That is, when the subject is in a normal mounting state where it can be detected, detection signals are output from all the position detection sensors LSN, and the subject is not mounted uniformly over the entire reading area. In such a state, no detection signal is output from any of the plurality of position detection sensors LSN. As a result, the operation control unit CON monitors the output states of the detection signals from the plurality of position detection sensors LSN, and thereby the reading area AR (detection surface F
d) It is possible to determine whether or not the subject SUB is placed at the normal position above.

The state in which the subject SUB is evenly placed over the entire reading area AR (normal placement state) is registered in advance in the identification and authentication processing of the read image executed in the authentication processing section ATS. The state in which the subject SUB is placed at a position where the predetermined feature point portion included in the two-dimensional image can be read well so that the comparison with the two-dimensional image can be performed well.

Further, the operation control section CON has various control operations (sensor device SE) as shown in the above-mentioned embodiment.
In addition to the image reading operation in N, the light emitting state in the light source unit LGT, and the image identifying operation in the authentication processing unit ATS described later), the detection surface Fd of the subject SUB is based on the detection signal output from the position detection sensor LSN. The placement state on the (reading area AR) is determined, and the subject position detection operation for controlling the light emission state of the light source unit LGT is executed based on the determination result.

The control operation of the image authentication apparatus (operation control section) according to this embodiment will be described below with reference to the drawings. Here, the description of the control operation equivalent to that of the above-described embodiment will be simplified or omitted. Figure 9
FIG. 6 is a light emission state diagram of a light source section showing an example of a control operation in the image authentication device according to the present embodiment. Here, for the sake of illustration, in order to clarify the difference in the emission color,
For convenience, different hatching is used.

In the image reading / authentication apparatus having the above-mentioned configuration, the mounting position of the subject is detected, the mounting state is notified, the two-dimensional image of the subject is read, the identification and authentication processing of the read image, and the authentication result. Each control operation of the notification is sequentially executed. First, in the operation of detecting the placement position of the subject, as shown in FIG. 9A, the person subject to authentication places the subject SUB such as a finger on the detection surface Fd on the upper surface of the sensor device SEN as described above. Based on the detection signals output from the plurality of position detection sensors LSN arranged in the peripheral area of the reading area AR, it is determined whether or not the subject SUB is in the normal mounting state.

Then, when the subject SUB is determined to be in the normal placement state based on the result of the placement position detection of the subject, the placement state notification operation is as shown in FIG. 9 (b). In addition, for example, by controlling the light emission of the blue light emitting diode (blue LED) LDb of the light source unit LGT to emit blue light and cause the detection surface Fd (reading area AR) to emit blue light, a person to be authenticated is authenticated. , It informs that the mounting state (mounting position) of the subject SUB is normal.

On the other hand, when it is determined that the subject SUB is not in the normal mounting state, as shown in FIG. 9C, for example, the red light emitting diode (red LE of the light source unit LGT is used.
D) The emission state of LDr is controlled so that red light is emitted and the detection surface Fd (reading area AR) emits red light, whereby the placement state (placement position) of the subject SUB on the person to be authenticated is determined. It informs that it is not normal and urges correction to a normal mounting state. The notification operation of the mounting state is repeatedly executed until the subject SUB is in the normal mounting state on the detection surface Fd (reading area AR).

Next, in the above-described subject placement position detecting operation, the two-dimensional image reading operation is executed only when it is determined that the subject SUB is in a normal placement state, and the capacitance detection type or A two-dimensional image of the subject SUB is read by applying the optical image reading method. Here, as a light source used for an optical two-dimensional image reading operation, as shown in FIG. 9C, a light source used for a mounting state informing operation, for example, a predetermined light emitting diode of the light source unit LGT ( For example, a red LED; LDr) may be used to perform setting control so that a part or the whole of the detection surface Fd on which the finger is placed emits light (red emission) in a predetermined color.

Thereafter, similar to the above-described embodiment, the identification and authentication processing of the read image is executed, and the subject SUB is read based on the two-dimensional image read by the reading operation of the two-dimensional image.
And determines whether the person to be authenticated is an authorized person. Then, based on the result of the identification and authentication processing, when the notification result of the authentication result is executed and the authentication target person is authenticated, as in the case shown in FIG. 9B, the detection surface Fd is displayed. By emitting blue light, the person to be authenticated is notified that the authentication is permitted (the result of the authentication determination), and the two-dimensional image data captured by the authentication processing unit ATS is registered in advance in the authentication processing unit ATS. When the person to be authenticated is not permitted to be authenticated (authentication is rejected) because it does not match the two-dimensional image data of the subject SUB for the person to be authenticated, the same as the case shown in FIG. 9C. By making the detection surface Fd emit red light, or as shown in FIG. 9D, for example, a yellow light emitting diode (yellow LED) LDy of the light source unit LGT is used.
Is controlled to emit yellow light to cause the detection surface Fd to emit yellow light, thereby informing the authentication target person that authentication has been rejected (the result of authentication determination).

As described above, according to the image authentication apparatus of the present embodiment, in addition to the operation and effect of the above-described embodiment, the luminescent color of the detection surface allows the subject to be placed on the detection surface visually. Since the information can be notified and transmitted, the person to be authenticated can accurately and quickly recognize the mounting state (operating state), and when the mounting state (mounting position) of the subject is not normal, It is possible to appropriately correct the placement position of the subject so that the normal placement state is quickly achieved.
Therefore, the identification / authentication process of the read image is normally executed, and the authentication is rejected because the placement state of the subject is poor even though the person is authorized for authentication. Therefore, it is possible to provide an image authentication device with higher authentication accuracy.

[0054]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a configuration example of a sensor device (image reading means) applicable to the image authentication apparatus according to the present invention will be described. The sensor device applicable to the image authentication apparatus according to the present invention is a CCD which is an optical image reading means.
A solid-state imaging device such as (Charge Coupled Device) can be used.

As is well known, the CCD is a photodiode or a thin film transistor (TFT: Thin Film Transistor).
Photosensors, etc., are arranged in a matrix, and the amount of electron-hole pairs (charge amount) generated corresponding to the amount of light applied to the light receiving portion of each photosensor is determined by the horizontal scanning circuit and the vertical scanning circuit. The brightness of the irradiation light is detected by the scanning circuit. By the way, in such a sensor device (photo sensor system) using a CCD,
Since it is necessary to individually provide a selection transistor for bringing each scanned photosensor into a selected state, there is a problem that the system itself becomes large as the number of detected pixels increases.

Therefore, in recent years, as a structure for solving such a problem, a thin film transistor having a so-called double gate structure (hereinafter, referred to as "double gate", in which a photo sensor itself has a photo sensing function and a selection transistor function. Type transistor ”) has been developed, and attempts have been made to miniaturize the system and increase the density of pixels. Then, the photosensor system to which such a double gate type transistor is applied can be favorably applied to the above-described image authentication device according to the present invention.

Here, a photosensor using a double gate type transistor (hereinafter referred to as a "double gate type photosensor") applied to the image authentication apparatus according to the present invention will be described with reference to the drawings. <Double Gate Photo Sensor> FIG. 10 is a sectional structural view showing a schematic configuration of a double gate photo sensor.

As shown in FIG. 10A, the double-gate photosensor 10 includes a semiconductor layer such as amorphous silicon in which electron-hole pairs are generated when excitation light (here, visible light) is incident. (Channel layer) 11 and semiconductor layer 1
1. Impurity layers 17 and 18 made of n ⁺ silicon provided at both ends of 1 and selected from chromium, chromium alloy, aluminum, aluminum alloy, etc. formed on the impurity layers 17 and 18 and opaque to visible light Drain electrode 12 and source electrode 13, and a block insulating film 14 and an upper (top) gate insulating film 15 above the semiconductor layer 11 (above the drawing).
A top gate electrode (first gate electrode) 21 which is formed of a transparent electrode layer such as ITO and which is transparent to visible light, and a lower portion (bottom portion) below the semiconductor layer 11 (lower portion in the drawing). ) A bottom gate electrode (second gate electrode) 22 selected from chromium, a chromium alloy, aluminum, an aluminum alloy or the like formed through the gate insulating film 16 and opaque to visible light. Has been done. The double-gate photosensor 10 having such a configuration is formed on a transparent insulating substrate 19 such as a glass substrate.

Here, in FIG. 10A, the top gate insulating film 15, the block insulating film 14, the bottom gate insulating film 16, and the protective insulating film 20 provided on the top gate electrode 21 are formed of the semiconductor layer 11. By a material having a high transmittance for excited visible light, for example, silicon nitride, silicon oxide, ITO, etc.,
It has a structure for detecting only light incident from above the drawing.

The double-gate type photosensor 10 is generally represented by an equivalent circuit as shown in FIG. Here, TG is the top gate electrode 2
1 is a top gate terminal electrically connected, BG is a bottom gate terminal electrically connected to the bottom gate electrode 22, S is a source terminal electrically connected to the source electrode 13, and D is a drain electrode 12. It is a drain terminal electrically connected.

Next, a drive control method of the above-mentioned double gate type photo sensor will be described with reference to the drawings. FIG. 11 is a timing chart showing an example of a basic drive control method for a double-gate photosensor,
FIG. 12 is a conceptual diagram of the operation of the double-gate type photo sensor, and FIG. 13 is a diagram showing the optical response characteristics of the output voltage of the double-gate type photo sensor. Here, description will be given with reference to the configuration of the above-described double-gate photosensor (FIG. 1) as appropriate.

First, in the reset operation (initialization operation), as shown in FIGS. 11 and 12A, a pulse voltage (hereinafter referred to as “reset pulse”) is applied to the top gate terminal TG of the double-gate type photo sensor 10. Note; for example, Vtg
= + 15V high level) φTi is applied to the semiconductor layer 11 and the semiconductor layer 11 in the block insulating film 14.
Carriers (here, holes) accumulated near the interface with and are released (reset period Trst).

Next, in the light accumulation operation (charge accumulation operation), as shown in FIGS. 11 and 12B, the top gate terminal TG is at a low level (for example, Vtg = -15V).
By applying the bias voltage φTi of, the reset operation is completed and the light accumulation period Ta by the carrier accumulation operation is completed.
Will start. In the light accumulation period Ta, the semiconductor layer 11 is changed depending on the amount of light incident from the top gate electrode 21 side.
Of electrons in the effective incident area of
Hole pairs are generated, near the interface between the semiconductor layer 11 and the semiconductor layer 11 in the block insulating film 14, that is,
Holes are accumulated around the channel region.

In the precharge operation, as shown in FIGS. 11 and 12C, in parallel with the light accumulation period Ta, a predetermined voltage (precharge) is applied to the drain terminal D based on the precharge signal φpg. The voltage) Vpg is applied to hold the charge in the drain electrode 12 (precharge period Tprch). Next, in the read operation, as shown in FIG.
As shown in FIG. 12D, after the precharge period Tprch has passed, a high level (eg, Vbg = + 10V) bias voltage (read selection signal; hereinafter referred to as “read pulse”) is applied to the bottom gate terminal BG. By applying φBi (selected state), the double gate photosensor 10 is turned on (reading period Tread).

Here, in the read period Tread,
Carriers (holes) accumulated in the channel region act in the direction of relaxing Vtg (-15V) applied to the top gate terminal TG having the opposite polarity, and thus Vbg of the bottom gate terminal BG.
(+ 15V) forms an n-channel, and the voltage of the drain terminal D (drain voltage) VD according to the drain current.
Is the precharge voltage Vpg as shown in FIG.
It shows a gradual decrease with time.

That is, when the light accumulation state in the light accumulation period Ta is the bright state, as shown in FIG.
Since carriers (holes) corresponding to the amount of incident light are trapped in the channel region, they act to cancel the negative bias of the top gate terminal TG, and the positive bias of the bottom gate terminal BG causes the double bias by the canceled amount. The gate photosensor 10 is turned on. Then, according to the ON resistance corresponding to the incident light amount, the drain voltage VD is lowered as shown in FIG.

On the other hand, when the light storage state is dark and no carriers (holes) are stored in the channel region, a negative bias is applied to the top gate terminal TG as shown in FIG. 12 (e). By this, the positive bias of the bottom gate terminal BG is canceled, the double gate type photo sensor 10 is turned off, and as shown in FIG.
The drain voltage VD is maintained almost as it is.

Therefore, as shown in FIG. 13A, the tendency of the drain voltage VD to change is that the read pulse is applied to the bottom gate terminal BG from the end of the reset operation by applying the reset pulse φTi to the top gate terminal TG. Time until φBi is applied (light accumulation period Ta)
It is closely related to the amount of light received, and tends to decrease sharply when there are many accumulated carriers (bright state), and gradually decreases when there are few accumulated carriers (dark state). Indicates. Therefore, the read period T
By detecting the drain voltage VD (= Vrd) after a lapse of a predetermined time from the start of read, or by detecting the time until the voltage reaches the predetermined threshold voltage as a reference. The amount of light (irradiation light) incident on the double-gate photosensor 10 is converted.

The double gate type photo sensor operates as a two-dimensional sensor system by repeating the same processing procedure for the double gate type photo sensor 10 in the i + 1-th row with the series of image reading operations described above as one cycle. Can be made. In the timing chart shown in FIG. 11, after the precharge period Tprch has passed, as shown in FIGS. 12F and 12G, a low level (for example, Vbg = 0V) is applied to the bottom gate terminal BG. When the state (non-selected state) is continued, the double-gate photosensor 10 continues to be in the OFF state, and the drain voltage VD changes to the precharge voltage V as shown in FIG. 13B.
Holds a voltage close to pg. In this way, the selection function of switching the reading state of the double-gate photosensor 10 to the selected / non-selected state is realized depending on the state of the voltage applied to the bottom gate terminal BG.

<Photo Sensor System> Next, a photo sensor system including a photo sensor array configured by arranging the above-described double gate type photo sensors in a predetermined format will be described with reference to the drawings. here,
A photosensor array configured by arranging a plurality of double gate type photosensors in a two-dimensional manner will be shown and described. However, a plurality of double gate type photosensors are arranged in a one-dimensional manner in the X direction to form a line sensor array. Needless to say, the two-dimensional area may be scanned by moving the line sensor array in the Y direction orthogonal to the X direction.

FIG. 14 is a schematic configuration diagram of a photosensor system including a photosensor array configured by arranging double-gate photosensors two-dimensionally. As shown in FIG. 14, the photosensor system is roughly classified into a large number of double gate photosensors 10, for example, n rows × m.
Photosensor array 100 arranged in a matrix of columns (n and m are arbitrary natural numbers), and top gate terminal TG (top gate electrode 21) and bottom gate terminal BG (bottom gate electrode 2) of each double-gate photosensor 10.
2) are connected in the row direction to extend, and a top gate line 101 and a bottom gate line 102, and a drain line (data line) in which the drain terminal D (drain electrode 12) of each double-gate photosensor 10 is connected in the column direction ) 103, the source terminal S (source electrode 13) in the column direction, and the source line (common line) 104 connected to the ground potential, the top gate driver 110 connected to the top gate line 101, and the bottom. A bottom gate driver 120 connected to the gate line 102 and a drain driver 130 including a column switch 131, a precharge switch 132, and an amplifier 133 connected to the drain line 103 are included.

Here, the top gate line 101 is integrally formed of a transparent electrode layer such as ITO together with the top gate electrode 21 shown in FIG. 10, and the bottom gate line 102, the drain line 103 and the source line 10 are formed.
4 is a bottom gate electrode 22 and a drain electrode 1 respectively
2. The source electrode 13 and the source electrode 13 are integrally formed of a material that is opaque to the same excitation light. Further, a constant voltage Vss set according to a precharge voltage Vpg described later is applied to the source line 104, but may be a ground potential (GND).

In FIG. 14, φtg is a control signal for generating signals φT1, φT2, ... φTi, ... φTn which are selectively output as either the reset voltage or the photocarrier storage voltage, and φbg Is a control signal for generating signals φB1, φB2, ... φBi, ... φBn that are selectively output as either the read voltage or the non-read voltage, and φpg controls the timing of applying the precharge voltage Vpg. This is a precharge signal.

In such a structure, from the top gate driver 110 through the top gate line 101,
By applying a signal φTi (i is an arbitrary natural number; i = 1, 2, ... N) to the top gate terminal TG, the photo sense function is realized, and the bottom gate driver 12
The signal φBi is applied to the bottom gate terminal BG from 0 through the bottom gate line 102, and the drain line 10
The detection signal is taken into the drain driver 130 via the output signal V and the output voltage V of the serial data or parallel data is output.
By outputting as out, the selective reading function is realized.

FIG. 15 is a cross-sectional view of the main parts of a sensor device (image reading means) to which the above-described photo sensor system is applied. Note that, here, an operation in the case of reading an image pattern (fingerprint) of a finger as a subject will be described. Further, for convenience of illustration, hatching showing a cross-sectional portion of the photo sensor system is omitted. As shown in FIG. 15, a sensor device S for reading an image pattern such as a fingerprint
In EN, irradiation light La is made incident from a backlight (surface light source) BL provided on the lower side of an insulating substrate 19 such as a glass substrate on which the double gate photosensor 10 is formed, and the irradiation light La is double gated. Photo sensor 1
0 (specifically, bottom gate electrode 22, drain electrode 1
2. Except for the area where the source electrode 13) is formed, the transparent insulating substrate 19 and the insulating films 15, 16 and 20 are penetrated and placed on the detection surface (fingerprint detection surface) Fd on the upper surface of the protective insulating film 20. The subject (finger) SUB is irradiated.

Here, during the fingerprint reading operation by the sensor device SEN, the semitransparent layer of the skin surface layer FPs of the finger, which is the subject SUB, contacts the sensing surface Fd (protective insulating film 20) on the uppermost surface of the sensor device SEN. By doing so, an air layer having a low refractive index disappears at the interface between the protective insulating film 20 and the skin surface layer FPs. Note that it is generally known that the thickness of the skin surface layer FPs is thicker than 650 nm. Therefore, the light La incident inside the convex portion FPa of the fingerprint FP propagates while being scattered and reflected in the skin surface layer FPs. .

Then, a part of the propagated light Lb passes through the transparent insulating films 20, 15, 14 and the transparent top gate electrode 21 and is incident on the semiconductor layer 11 of the double gate type photosensor 10 as excitation light. To be done. In this way, carriers (holes) generated by light incident on the semiconductor layer 11 of the double-gate photosensor 10 arranged at the position corresponding to the convex portion FPa of the subject (finger) SUB are accumulated. Thus, the image pattern (fingerprint FP) of the subject (finger) SUB can be read as the light and dark information according to the series of drive control methods described above.

In the recess FPb of the fingerprint FP,
The light La emitted from the backlight BL is detected by the detection surface Fd.
Passes through the interface between the air layer and the air layer, reaches the subject (finger) SUB at the tip of the air layer, and scatters in the skin surface layer FPs. However, since the skin surface layer FPs has a higher refractive index than air, at a certain angle. The light Lc in the skin surface layer FPs incident on the interface is less likely to escape to the air layer, and the incidence on the semiconductor layer 11 of the double gate photosensor 10 arranged at the position corresponding to the recess FPb is suppressed.

When the photo sensor system which is such an optical image reading means is applied to the image authentication device according to the present invention as the image reading means, it is essential for the image reading operation in the photo sensor system. The backlight BL having the above configuration can also be used as the above-described light source unit LGT according to the present invention. That is, in the reading operation of the above-described photo sensor system, the double gate type photo sensor 10 is reflected by the subject SUB.
The reflected light that is incident on the semiconductor layer 11 needs to have an excitation energy that can satisfactorily accumulate charges corresponding to the image pattern of the two-dimensional image of the subject, and thus the reflected light from the backlight BL to the subject SUB. The light radiated on the light may have various emission colors.

Specifically, in the above-described photo sensor system, when the semiconductor layer 11 of the double gate type photo sensor 10 is made of amorphous silicon,
Since the excitation-sensitive emission band is mainly the visible light band, the backlight BL (that is, the light source unit L) is used during the image reading operation.
When monochromatic visible light other than white is used as the irradiation light emitted from the GT) to the subject SUB, the emission color of the light emitting diode that emits a predetermined visible light color (for example, the red light of the red light emitting diode LDr). In addition, when white light is adopted, a combination of the combined colors of the light emitting diodes which emit light of a plurality of different colors from the white light (for example, the red light of the red light emitting diode LDr and the green light emitting diode LDg Of the green light and the blue light of the blue light emitting diode LDb or the combination of the yellow light of the yellow light light emitting diode LDy and the blue light of the blue light emitting diode LDb) In addition, when performing an operation of notifying the identification / authentication result, by controlling the light emission of one of the light emitting devices corresponding to each of the above emission colors, the image authentication device is controlled. Light of any color (red light, green light, blue light, yellow light, or combined light of any combination of these) is emitted according to the operating state of the detection surface Fd to emit a predetermined light. Can emit light in colors. Further, as the configuration of the backlight BL (light source unit LGT), as described above, a light emitting device capable of changing and controlling the emission color according to the applied current can be applied.

Therefore, in the image authentication apparatus according to the present invention, in the light source section which emits light of different colors and the photo sensor system in the notification operation of the placement state of the subject and the notification operation of the identification and authentication result, When a two-dimensional image of a subject is read, a backlight that emits irradiation light of a predetermined color is shared (shared), and the operation control unit controls the light emitting state of the light emitting device. In addition to being able to intuitively visually recognize the operation state of the image authentication device by controlling the emission color of the detection surface in each control operation as shown in each of the above-described embodiments, the essential configuration for the photo sensor system Since the (backlight BL) can be directly applied to the light source unit LGT according to the present invention, it is not necessary to newly provide a configuration related to the light source unit, and the device scale is small. It is possible to achieve a significant reduction of the reduction and product cost.

In this embodiment, a double gate type photosensor is applied as a sensor device applicable to the image authentication apparatus according to the present invention. It is needless to say that the present invention is not limited to the above, and can be favorably applied to a photosensor system using a photosensor having another configuration such as a photodiode or a TFT.

Next, another configuration example of the sensor device (image reading means) applicable to the image authentication apparatus according to the present invention will be described with reference to the drawings. As the sensor device applicable to the image authentication apparatus according to the present invention, in addition to the above-described optical image reading unit, an electrostatic capacitance detection type image reading unit can be applied. Here, as the electrostatic capacitance detection type image reading means, for example, a so-called silicon chip sensor structure in which detection electrodes and the like are arranged on a silicon substrate can be favorably applied.

FIG. 16 is a schematic diagram showing a capacitance detection type sensor device (silicon chip sensor).
FIG. 17 is a conceptual diagram showing the principle of the reading operation of the two-dimensional image of the subject in the silicon chip sensor. Note that, in FIG. 17, for convenience of illustration, hatching showing a cross-sectional portion of the silicon chip sensor is omitted. FIG.
As shown in (a) and (b), the structure of the silicon chip sensor is roughly the reading area AR of the detection surface Fd on the silicon substrate 41 via the transparent insulating film 42 made of a silicon oxide film or the like. A plurality of transparent detection electrodes 43 made of a transparent electrode material such as ITO, which are two-dimensionally arranged in a region, a switching element (not shown) such as a transistor connected to each transparent detection electrode 43, and a plurality of transparent detections Electrode 43
And a transparent dielectric layer 44 formed at least over the detection area AR so as to cover the switching element,
Is configured. Here, the upper surface of the dielectric layer 44 constitutes the detection surface Fd in the image recognition device according to the present invention.

In the silicon chip sensor having such a structure, as shown in FIG.
When B is placed on the detection surface Fd on the upper surface of the transparent dielectric layer 44,
A capacitor Cs is formed between the subject SUB and each transparent detection electrode 43 facing each other through the transparent dielectric layer 44. Here, the capacitance of each capacitor Cs is large in the convex portion FPa of the fingerprint FP because only the transparent dielectric layer 44 is interposed between the subject (finger) SUB and the transparent detection electrode 43. In addition, in the concave portion FPb of the fingerprint FP, an air layer is present in addition to the transparent dielectric layer 44 between the subject (finger) SUB and the transparent detection electrode 43, which is small. Therefore, the image pattern (fingerprint FP) of the subject (finger) SUB is read by detecting the difference (change) in the capacitance of each capacitor Cs in each such transparent detection electrode 43.

When the silicon chip sensor, which is such an electrostatic capacitance detection type image reading means, is applied to the image authentication apparatus according to the present invention, the sensor device is the same as in the above embodiments. The light emitting unit 1 (not shown) of the light source unit LGT is provided on the side surface of the SEN (silicon chip sensor), and the transparent insulating film 42, the transparent detection electrode 43, and the transparent dielectric layer 44 also serve as the light guide plate 2. Have In this way, the detection surface Fd on the upper surface of the sensor device SEN is caused by the light emitted from the light source unit LGT according to the operation state of the image authentication apparatus (the state of placement of the subject or the result of the identification and authentication processing of the read image). In order to emit light with a predetermined emission color, each cross-sectional structure of the silicon chip sensor is made of a translucent material.

When a transparent insulating substrate such as glass is used instead of the silicon substrate 41 constituting the above-described silicon chip sensor, each of the above-described embodiments is provided on the back side of the sensor device SEN. Like the form,
By disposing the light source unit LGT including the light emitting unit 1 and the light guide plate 2, the electrostatic capacitance detection type sensor device (image reading unit) can be favorably applied to the image authentication apparatus according to the present invention.

In each of the above-mentioned embodiments, the capacitance detection type and optical type image reading means are shown as the constitutional example of the sensor device applicable to the image authentication apparatus according to the present invention. Is not limited to these methods. In short, based on the output signal output from the detection element provided corresponding to the two-dimensional image of the subject, at least the characteristic portion included in the two-dimensional image of the subject. A sensor device having another configuration may be used as long as it can read. The image authentication device according to the present invention is a mobile device such as a mobile phone or a personal digital assistant,
By connecting or directly mounting to a computer such as a personal computer or a server device, it can be favorably applied as a security device for use of application software or for authentication for accessing personal information.

[0089]

As described above, according to the image authentication apparatus of the present invention, in the image authentication apparatus which reads a two-dimensional image of a desired subject and judges the subject authentication based on the two-dimensional image, various image authentication apparatuses can be used. Since the detection surface on which the subject is placed emits light in a predetermined color according to various operating states, the authentication target person on which the subject is placed can perform image authentication based on the emission color of the detection surface. Since the operating state of the device can be visually recognized, the operating state can be accurately notified and transmitted, and there is no need to provide a configuration of a display device or the like separately from the image authentication device. It is possible to favorably suppress the increase in size and the increase in product cost.

Here, the operation state of the image authentication apparatus means, for example, whether the position of the subject placed on the detection surface is normal, whether the image reading operation for reading a two-dimensional image of the subject is in progress, or , The result of the authentication determination of the read two-dimensional image of the subject, etc., and the emission color of the detection surface is controlled to be different depending on these suitability. Prior to the operation of reading, whether or not the subject is placed at a normal position on the detection surface, whether or not the reading operation of the two-dimensional image is performed, or the read two-dimensional image is On the basis of the light emission color of the detection surface, the state and result of whether or not the person to be authenticated has been authenticated can be accurately recognized visually.

Further, in the above image authentication apparatus, the light source section may be composed of a single light emitting device capable of emitting light of two or more different colors, or individual light emitting colors may be used. It may be composed of a light emitting device. According to this, in the former case,
Since the detection surface can emit light in different colors with a single light emitting device, it is possible to further suppress the increase in the scale of the device. In the latter case, by emitting a plurality of light emitting devices with a single color, respectively. Since the detection surface can be made to emit light in different colors, it is possible to easily control the light emission of the light emitting device.

Here, by setting, for example, red and blue as the emission colors of the detection surface emitted by the light source unit, in the case of the normal state or the normal operation depending on the suitability of the operation state of the image authentication device. Emits blue light,
Since red light emission can be performed in an abnormal state or abnormal operation, the authentication target person can intuitively visually recognize the operation state of the image authentication device by the emission color of the detection surface.

In the image authentication apparatus, as the light emitting device constituting the light source unit, for example, a light emitting diode element or an electroluminescent element, or a combination of a light emitting diode element and an electroluminescent element is preferably applied. Because you can
Compared with the case where a fluorescent tube or the like is applied as a light emitting device, the device scale including peripheral circuits can be significantly reduced in size and weight, and power consumption can be reduced. It is possible to realize an image authentication device that is more suitable for the specifications of small size, light weight, and low power consumption required at that time.

Further, in the above-mentioned image authentication device, the image reading means may be a capacitance detection type image reading system or an optical image reading system. According to this, the configuration of the present invention can be applied to an existing image reading unit applied as an image authentication device (particularly, a fingerprint authentication device) or an image reading unit which is being considered for practical use in the future. It can be applied well.

Here, as a light source unit, a backlight provided in an optical image reading means is applied (combined), and a light emitting device constituting the backlight is used in accordance with the operating state of the image authentication apparatus. By emitting light in different emission colors, the detection surface emits light of a predetermined color according to the operating state of the image authentication device, without changing the configuration of the optical image reading unit and only by simple light emission control. Can be made.

In the image authentication device, a so-called double gate type photo sensor can be applied as a photo sensor forming the image reading means, so that the photo sensor forming the image reading means can be made thin and small. It is possible to increase the density of read pixels, read a two-dimensional image of a subject as a high-definition image, and further improve the accuracy of authentication determination of a person to be authenticated based on the read two-dimensional image.

[Brief description of drawings]

FIG. 1 is a block diagram showing an overall configuration of a first embodiment of an image authentication device according to the present invention.

FIG. 2 is a schematic configuration diagram showing a configuration example of a light source unit applied to the image authentication apparatus according to the first embodiment,

FIG. 3 is a spectrum distribution diagram showing spectrum characteristics of light emitted from a light source unit applied to the image authentication apparatus according to the first embodiment.

FIG. 4 is a light emission state diagram of a light source section showing an example of a control operation in the image authentication apparatus according to the first embodiment.

FIG. 5 is a schematic configuration diagram showing another configuration example of the light source unit applied to the image authentication apparatus according to the first embodiment.

FIG. 6 is a schematic configuration diagram showing still another configuration example of the light source unit applied to the image authentication apparatus according to the first embodiment.

FIG. 7 is a block diagram showing the overall configuration of a second embodiment of the image authentication device according to the present invention.

FIG. 8 is a schematic configuration diagram showing a configuration example of an image authentication device according to a second embodiment.

FIG. 9 is a light emission state diagram of a light source unit showing an example of a control operation in the image authentication device according to the second embodiment.

FIG. 10 is a cross-sectional structure diagram showing a schematic configuration of a double-gate photosensor applied to the image authentication device according to the present invention.

FIG. 11 is a timing chart showing an example of a basic drive control method for a double-gate photosensor.

FIG. 12 is a conceptual diagram of the operation of a double gate type photo sensor.

FIG. 13 is a diagram showing an optical response characteristic of an output voltage of a double gate type photo sensor.

FIG. 14 is a schematic configuration diagram of a photosensor system including a photosensor array configured by arranging double-gate photosensors two-dimensionally.

FIG. 15 is a cross-sectional view of essential parts of a sensor device (image reading means) to which a photosensor system including a double-gate photosensor is applied.

FIG. 16 is a schematic configuration diagram showing a capacitance detection type sensor device (silicon chip sensor).

FIG. 17 is a conceptual diagram showing a principle of a reading operation of a two-dimensional image of a subject in a silicon chip sensor.

[Explanation of symbols]

SEN sensor device LGT light source CON operation control unit ATS authentication processing unit LSN position detection sensor SUB subject Fd detection surface

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H04N 1/04 ZEC G01B 11/24 F 1/48 K H04N 1/46 AF term (reference) 2F065 AA49 AA56 BB05 CC16 DD01 DD02 FF04 FF41 FF61 GG07 GG23 HH02 HH13 LL01 LL12 MM22 QQ21 QQ25 QQ28 QQ31 RR07 5B047 AA25 AB02 BA02 BB04 BC12 BC14 CA04 CA19 CB17 CB23 5C051 AA01 BA04 DA06 DB01 DB04 DB06 DB08 DB18 DB29 DB31 DC02 DC03 DC05 DE02 DE29 5C072 AA01 BA01 CA05 CA12 EA05 EA08 FA01 FB25 RA04 5C079 HB01 JA17 JA21 JA27 NA09

Claims (13)

[Claims] 1. The object 2 placed on a predetermined detection surface.
Image reading means for reading a three-dimensional image, and image identifying means for making an authentication decision on the subject based on the two-dimensional image,
In an image authentication device including: a light source unit that emits light in at least two different colors and irradiates the detection surface, and according to a predetermined operation state of the image authentication device,
An image authentication apparatus, wherein the light source unit emits light of a predetermined color. 2. The image authentication device has a position detecting means for detecting the position of the subject placed on the detection surface, and the position detecting means detects whether the position of the subject is normal or not. The image authentication apparatus according to claim 1, wherein the light source unit is controlled to emit light of different colors. 3. The image authentication device controls the light source unit so as to emit light of different colors according to the result of the authentication determination of the subject by the image identification means. The image authentication device described. 4. The image authentication apparatus, when the two-dimensional image of the subject is read by the image reading unit, controls the light source unit to emit light of a predetermined color. The image authentication device according to any one of 3 above. 5. The image authentication apparatus according to claim 1, wherein the light source unit is composed of a single light emitting device capable of emitting light of two or more different colors. 6. The image authentication apparatus according to claim 1, wherein the light source unit is configured by a light emitting device for each light emitting color. 7. The light source unit is capable of emitting at least red monochromatic light or composite color light composed of a plurality of colors, and blue monochromatic light or composite color light composed of a plurality of colors. 7. The image authentication device according to any one of 1 to 6. 8. The light source unit is configured by a light emitting diode element or an electroluminescent element, or a combination of a light emitting diode element and an electroluminescent element. The image authentication device according to claim 1. 9. The image reading means detects a change in capacitance between the subject and a plurality of electrodes that are two-dimensionally arranged corresponding to the detection surface to detect the change in capacitance of the subject. 2. A three-dimensional image is read.
9. The image authentication device according to any one of 8 to 8. 10. The image reading means includes a backlight for emitting a predetermined irradiation light on the back side of the detection surface, and the irradiation light is emitted from the backlight to the subject placed on the detection surface. A two-dimensional image of the subject is read by detecting the amount of reflected light that is emitted and reflected by the subject by a plurality of photosensors that are two-dimensionally arranged corresponding to the detection surface. The image authentication apparatus according to claim 1, wherein 11. The light source unit is a backlight provided in the image reading unit, and controls a light emission state of monochromatic light or composite color light composed of a plurality of colors that constitutes the irradiation light with which the subject is irradiated. The image authentication apparatus according to claim 10, wherein the image authentication apparatus emits light in a predetermined color according to a predetermined operation state of the image authentication apparatus. 12. A photo sensor constituting an image reading means is formed by interposing a source electrode and a drain electrode sandwiching a channel region made of a semiconductor layer and at least an insulating film above and below the channel region. A first gate electrode and a second gate electrode, the reset pulse is applied to the first gate electrode to initialize the photosensor, and the precharge pulse is applied to the drain electrode. By applying a read pulse to the second gate electrode, the read voltage is applied to the channel region according to the amount of reflected light reflected by the subject during the charge accumulation period from the end of initialization to the application of the read pulse. A voltage corresponding to the accumulated charges is output as an output voltage, and the image reading unit outputs a signal voltage related to the precharge pulse. The difference from the output voltage is observed as the signal component.
The image authentication device according to any one of 1. 13. The image authentication device is connected to any one of a mobile phone, a mobile device such as a personal digital assistant, a personal computer, and a computer of a server. The image authentication device described in.