JP2000090251A - Imaging device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an imaging device capable of being made thin in thickness and to reduce its producing cost. SOLUTION: Address light guide paths 2 are formed in practically parallel at a prescribed interval and guide incident light. An organic EL layer 12 is formed at one part of plural address light guide paths 2, is emitted corresponding to an impressed voltage and guides light to the address light guide paths 2. Data electrode 21 are successively formed at positions, where address sequential EL light emitting parts 10 are not formed, vertically to the address light guide paths 2 at a prescribed interval while storing prescribed charges. An optically conductive layer 23 is formed over plural address light guide paths 2 and plural data electrodes 21 and the resistance value of a part, to which light is made incident, is lowered. An insulated lightproof layer 22 shields light so as not to make light emitted from the address light guide path 2 directly incident to the optically conductive layer 23 on the data electrode 21. A transparent electrode 24 is grounded, laminated and formed on the optically conductive layer 23.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image sensor for reading an image of an object, and more particularly to an image sensor for reading an image of an object using light.

[0002]

2. Description of the Related Art A fingerprint sensor is known as an imaging device for reading an image of an object using light.

[0003] Fingerprints have a unique shape for each individual, and are easy to perform matching by pattern matching. Therefore, fingerprint sensors are widely used to identify specific individuals.

FIG. 8 shows an example of a fingerprint sensor using a CCD (Charge Coupled Device) as an image sensor which reads an image of an object.

[0005] The fingerprint sensor shown in FIG. 8 includes a right-angle prism 60 to which a total reflection film 60 a is attached, a light source 61, a lens 62, and a CCD 63. When a fingerprint pattern is read by this fingerprint sensor, the finger FG is placed on the right-angle prism 60 so that the surface of the fingerprint to be read comes into contact with the total reflection film 60a.

In this state, the right-angle prism 6 is
The light incident on 0 is absorbed by the convex portion of the fingerprint of the total reflection film 60a (actually, only this portion comes into contact with the total reflection film 60a), and is substantially reflected by the concave portion of the fingerprint, An image is formed on the CCD 63 by the lens 62.
Then, the CCD 63 detects the formed light,
Read the fingerprint pattern.

As an image pickup device other than the above, a double-gate TFT is used instead of a CCD as an image pickup device.
(Thin-Film Transistor).

In a two-dimensional image pickup apparatus using such a TFT, the TFTs are arranged in an XY matrix array, and image information for each pixel is read from the data line.

[0009]

However, in the fingerprint sensor described above, the light source 61 is formed by the right-angle prism 60.
It is necessary to change the angle of the light from
Therefore, an image must be formed on the CCD 63. For this reason, there is a problem that it is difficult to make the entire apparatus thin.

On the other hand, an imaging device using a TFT having a double gate structure uses a high melting point glass for a substrate and performs CVD (Chemical Vapor Deposition) or the like for element formation, so that the production cost is high. There's a problem.

Accordingly, it is an object of the present invention to provide an image pickup device capable of making the entire apparatus thin.

[0012]

In order to achieve the above object, an image pickup device according to a first aspect of the present invention is formed so as to be spaced apart from each other and to be formed substantially in parallel to guide incident light. A light guide path, and formed corresponding to a part of each of the plurality of light guide paths, emits light according to the applied voltage,
A plurality of light emitting elements that guide light to each of the plurality of light guide paths, and are separated from each other and substantially parallel to each other, and form a predetermined angle with the plurality of light guide paths, and the plurality of light emitting elements are not formed. A plurality of first electrodes formed at positions, and a plurality of first electrodes laminated at least at positions of intersections of the plurality of light guide paths and the plurality of first electrodes, and a predetermined wavelength range A photoconductive layer whose resistance changes when light is incident thereon, and a light blocking unit that blocks light so that light emitted from the light guide path does not directly enter the photoconductive layer.
A second electrode formed on the photoconductive layer so as to face the plurality of first electrodes corresponding to a position where the photoconductive layer is formed.

According to the present invention, it is possible to irradiate an object to be imaged with light, and to change the shape and shading of the object to be imaged by changing the resistance value of the photoconductive layer due to light reflected according to the object. Can be detected. Further, the light to be applied to the object to be imaged may be guided from the corresponding light emitting elements via a plurality of light guide paths. Therefore, in an imaging device to which this imaging device is applied, it is not necessary to use a right-angle prism or the like, and the entire imaging device can be configured to be thin.

Further, if the light guide path and the first or second electrode are finely structured, it is not necessary to perform complicated patterning of the photoconductive layer by performing a process such as photolithography or etching. Therefore, the production cost of the imaging device can be reduced.

[0015] The light emitting element and the photoconductive layer may be arranged so as to be separated from each other in the layer thickness direction so as not to overlap with each other.

The plurality of first electrodes are made of a material having light non-transmissivity, and are formed between the photoconductive layer and the plurality of light guide paths, and also serve as the light blocking means. You may.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a photo sensor according to a first embodiment of the present invention will be described.

FIG. 1 shows an image pickup section 2 constituting a photo sensor.
FIG. 3 is a diagram illustrating a configuration of an EL light emitting unit 10 in the order of 0 and address. FIG. 1A is a plan view illustrating a configuration when the imaging unit 20 and the address sequential EL light emitting unit 10 are viewed from above. FIG. 1B shows a cross-sectional configuration when cut along AA in FIG. 1A.

As shown in FIGS. 1A and 1B, a plurality of address guides extend between an image pickup section 20 and an address sequential EL light emitting section 10 on a substrate 1 made of glass or the like. The light paths 2 are formed substantially parallel to each other. The address light guide path 2 guides the light emitted from the EL light emitting unit 10 in the address order, radiates the light into the photoconductive layer 23, and irradiates the object to be imaged.

The address-sequential EL light-emitting section 10 includes an anode electrode 11, an organic EL (electroluminescence) layer 12, a cathode electrode 13, and a sealing film 14.

The anode electrode 11 is made of ITO (Indium Tin).
Oxide). As shown in FIG. 1A, the same number of the anode electrodes 11 as the number of the address light guide paths 2 are formed, and as shown in FIG.
It is formed on one end of the address light guide path 2.

The organic EL layer 12 is formed on the entire surface of the EL light emitting section 10 in order of address so as to cover a part of the anode electrode 11. For example, a hole transport layer (not shown) formed on the anode electrode 11 side And an electron transporting light emitting layer (not shown) formed on the cathode electrode 13 side. The hole transport layer is formed of α-NPD represented by Chemical Formula 1.

[0023]

Embedded image

The electron transporting light emitting layer is composed of Be
bq2.

[0025]

Embedded image

The organic EL layer 12 emits light in a predetermined wavelength range when a predetermined voltage is applied. In this case, the organic EL
The layer 12 emits light in a green wavelength range, and this wavelength range is included in a spectral sensitivity characteristic of a photoconductive layer 23 of the imaging unit 20 described later. The light emitted from the organic EL layer 12 enters the address light guide path 2 and is
The light travels through the inside and is emitted into the imaging unit 20.

The cathode electrode 13 is made of MgAg, MgI
n, an electrode formed of AlLi or the like, and an organic EL layer 1
2 on the entire surface. Further, the potential of the cathode electrode 13 is grounded so as to be zero.

The sealing film 14 is formed on the cathode electrode 13 as shown in FIG. 1 (b) in order to prevent oxygen or water from entering the organic EL layer 12, the cathode electrode 13 and the like. Note that the sealing film 14 may be formed by laminating an inorganic or organic resin or the like.

The imaging section 20 includes a data electrode 21, a light-shielding layer 22, a photoconductive layer 23, a transparent electrode 24, and a protective film 25.

The light-shielding layer 22 is made of a material that shields light propagating from the address light guide 2, and is substantially perpendicular to the address light guide 2 as shown in FIG. The plurality of address light guide paths 2 are formed substantially parallel to each other at a predetermined interval.

The data electrodes 21 are shown in FIGS. 1 (a) and 1 (b).
As shown in FIG. However, in order to prevent light emitted from the address light guide path 2 from directly entering the upper part of the data electrode 21, the data electrode 21
Is formed narrower than the width of the light shielding layer 22, as shown in the figure. Further, the data electrode 21 is made of MgAg, MgIn,
It is formed of AlLi or the like.

The photoconductive layer 23 is formed on the address light guide 2, the light shielding layer 22, and the data electrode 21, as shown in FIG. The photoconductive layer 23 is made of CdS (cadmium sulfide) or eosine shown in Chemical Formula 3.
Visible light (wavelength: about 4) such as ZnO (zinc oxide) containing
(00 nm to 800 nm).

[0033]

Embedded image

When the photoconductive layer 23 absorbs visible light (hereinafter, simply referred to as "light"), carriers, that is, holes and electrons are generated inside the portion where the light is absorbed. Therefore,
The resistance is reduced at the location where the light is applied. On the other hand, the portion of the photoconductive layer 23 where light is not incident has a high resistance value,
It is insulated. As can be seen from FIG.
When light is emitted from the address light guide path 2, the light is blocked by the light blocking layer 22, so that the photoconductive layer 23 above the data electrode 21 does not directly show conductivity due to the light from the address light guide path 2. .

The transparent electrode 24 is an electrode formed of ITO or the like and transmitting visible light. As shown in FIG.
It is formed on the entire surface of the photoconductive layer 23 and is grounded.

The protective film 25 is made of transparent glass, plastic, or the like, is formed on the transparent electrode 24, and protects the imaging unit 20 from an external environment (such as dust). Since the image of the object is obtained through the protective film 25, 200D
When obtaining a resolution higher than PI, the thickness of the protective film 25 is desirably 60 μm or less.

The address sequential EL light emitting section 10 described above
And the imaging unit 20, as shown in FIG.
It is formed on the top and is connected by the address light guide path 2,
They are formed at positions separated from each other. Therefore, the organic EL layer 12 using organic molecules that are vulnerable to high temperatures,
It is more desirable to form after forming.

As described above, the address light guide path 2 has a refractive index such that the light emitted from the address-sequential EL light emitting section 10 can be radiated into the image pickup section 20. That is, since the refractive index of the substrate 1 is set to be smaller than the refractive index of the address light guide path 2, the address-sequential EL light emitting section 10
Is transmitted through the address light guide path 2 and transmitted through the address light guide path 2 with little loss while being substantially reflected in the address light guide path 2.
In the imaging unit 20, the refractive index of the address light guide path 2 is set equal to or smaller than the refractive index of the photoconductive layer 23.
The light is emitted into the photoconductive layer 23 from the interface between the address light guide path 2 and the photoconductive layer 23.

Next, the image pickup section 20 and the address sequential E
A drive system of the L light emitting unit 10 will be described.

FIG. 2 is a diagram showing the configuration of this drive system.

The address sequential EL light emitting section 10 and the image pickup section 20
The driving system of FIG.
0, a data line signal readout circuit 40, and a control unit 50.

The portion of the image pickup section 20 shows an equivalent circuit. The broken line in the drawing indicates the address light guide path 2, and the variable resistor indicates the photoconductive layer 23 on the data electrode 21 near the position where the address light guide path 2 and the data electrode 21 intersect. As described above, since the photoconductive layer 23 is in an insulated state when no light is incident thereon, the resistance value of the variable resistor is maximized.

The address driver circuit 30 is connected to the plurality of anode electrodes 11, sequentially applies a voltage to the anode electrodes 11 according to a control signal from the control unit 50, and selectively emits light to the address light guide path 2. Therefore, the address light guide paths 2 are selected one by one and emit light into the imaging unit 20.

The data line signal reading circuit 40 is connected to the plurality of data electrodes 21 and makes the data electrodes 21 have a certain potential in response to a control signal from the control unit 50. As described above, since the light selected and emitted from the address light guide path 2 is blocked by the light shielding layer 22, the resistance value of the photoconductive layer 23 does not change from this state. However, if an object is present on the imaging unit 20 and the light reflectance of the object is high, the light emitted from the address light guide 2 is reflected and reenters the photoconductive layer 23. Since the reflected light is reflected at some angle, the photoconductive layer 23 (especially the position where the address light guide path 2 and the data electrode 21 intersect each other in the vicinity where the object exists (the position
The light is not directly emitted from the address light guide path 2).

For example, if an object having high light reflectivity exists above the variable resistor R, the reflected light re-enters the resistor R.
Decrease in resistance value. Then, in the data electrode 21 connected to the resistor R, the stored electric charge is transferred to the resistor R.
And escapes to the transparent electrode 24 to change its potential.
The data line signal read circuit 40 also detects the potential change of the data electrode 21 and outputs the detection result to the control unit 50 as a detection signal.

The control section 50 outputs various control signals to be described later to control the operations of the address driver circuit 30 and the data line signal reading circuit 40.

Next, the operation of the photosensor having the above configuration will be described with reference to FIG.

FIG. 3 shows a state where an object to be imaged (for example, a fingerprint) is placed on the image pickup section 20 and the image is read.

First, the control section 50 outputs a charging signal to the data line signal reading circuit 40 to instruct the data electrode 21 to have a constant potential (other than 0 V).

The data line signal reading circuit 40 charges the data electrode 21 positively or negatively in response to the charging signal from the control unit 50.

Next, the control section 50 outputs a voltage application signal to the address driver circuit 30 so as to selectively apply a voltage to the anode electrode 11 of the address sequential EL light emitting section 10. The voltage application to the anode electrode 11 is performed one by one in order.

The address driver circuit 30 responds to a voltage application signal from the control unit 50 by
1 is applied with a voltage.

In the address sequential EL light emitting section 10, when a voltage is applied to the anode electrode 11, the organic EL of that portion is applied.
A voltage in the thickness direction is applied to the layer 12. Therefore, the organic EL layer 12 in the portion where the voltage is applied emits light.

The light emitted from the organic EL layer 12 is incident on the address light guide path 2 in the portion where the light is emitted.

Light incident on the address light guide path 2 is radiated from the interface with the photoconductive layer 23 into the photoconductive layer 23 in the imaging section 20 while traveling through the address light guide path 2. As described above, the address light guide paths 2 are selected one by one and emit light into the photoconductive layer 23.

Light selected and emitted from the address light guide path 2 passes through the photoconductive layer 23, the transparent electrode 24, and the protective film 25 from between the light shielding layers 22 of the imaging section 20 as shown in FIG. The light passes through and irradiates the imaging target.

When the object to be imaged is, for example, a fingerprint, this light is reflected at the interface of the protective film 25 corresponding to the concave portion of the fingerprint, and reenters the imaging unit 20. On the other hand, at the interface of the protective film 25 corresponding to the convex part of the fingerprint, light escapes from the protective film 25 through the fingerprint convex part, so that the light hardly enters the photoconductive layer 23 on the corresponding data electrode 21. As shown in FIG. 3, the incident intensity of the reflected light changes depending on the shape of the imaging target, that is, whether the imaging target is in contact with the protective film 25 or not. Light is not efficiently reflected in a portion where the imaging target is in contact with the protective film 25, but light is efficiently reflected in a portion not in contact with the protective film 25.

The light reflected at the portion where the object to be imaged is not in contact with the protective film 25 is transmitted to the photoconductive layer 23 of the imaging section 20.
(Especially, a position where the address light guide path 2 and the data electrode 21 cross each other).

At the portion where the reflected light is incident on the photoconductive layer 23 at the position where the address light guide path 2 and the data electrode 21 intersect, a hole-electron pair is generated as described above. Becomes smaller. Therefore, the charge stored in the data electrode 21 corresponding to the portion where the resistance of the photoconductive layer 23 is reduced by the light reflected by the imaging object (fingerprint concave portion) flows to the transparent electrode 24 through the photoconductive layer 23. , The potential of the data electrode 21 changes.

The data line signal readout circuit 40 controls the data electrode 2 according to the control signal from the control unit 50.
1 is detected and output to the control unit 50 as a detection signal.

The control section 50 stores the detection signal input from the data line signal read circuit 40 as data.

Then, the control section 50 outputs a charging signal to the data line signal readout circuit 40 in order to make the address light guide path 2 of the next row emit light and capture an image.

The subsequent operation is the same as described above. Also,
The above operation is sequentially applied to the anode electrodes 11 of the EL light emitting section 10 in order of the address, and is repeated until the voltages are applied to all the anode electrodes 11. That is,
Light is sequentially incident on the address light guide paths 2, and this operation is repeated until light is incident on all the address light guide paths 2. And
The stored image of the imaging object is used for reproducing and collating the image.

Next, an image obtained by the above-described processing will be described with reference to FIG.

FIG. 4 shows a state where an object having a donut-shaped concave portion on the imaging section 20 and a flat portion other than the concave portion is placed.

The address light guide 2 passing through the imaging unit 20
And data electrode 21 are, as shown in FIG.
It is assumed that there are one (A1 to A11) and thirteen (D1 to D13). The bottom surface of the object is the protective film 2 of the imaging unit 20.
Assume that it is in contact with 5. Therefore, the intersection of the address light guide path 2 and the data electrode 21 corresponding to the portion that is not in contact with the protective film 25 due to the concave portion of the object is the point circled in FIG.

First, the data line signal reading circuit 4
0 charges the data electrode 21. Since light has not yet entered the photoconductive layer 23 of the imaging unit 20, the photoconductive layer 2
3 is an insulating state.

Next, the address driver circuit 30 sequentially applies a voltage to the anode electrode 11. As a result, the organic EL layer 12 emits light, and the light is sequentially incident on the address light guide path 2.

When the light radiated from the address light guide path 2 is reflected by the protective film 25 by the concave portion of the object to be imaged and re-enters the image pickup section 20, the resistance of the photoconductive layer 23 at that portion decreases. In FIG. 4, when the address light guide A3 emits light, a portion of the photoconductive layer 23 corresponding to a portion where the concave portion of the object exists, that is, A3-A3 of the address light guide A3.
The resistance of the photoconductive layer 23 near the portion corresponding to A1 to A3-2 decreases.

The data electrode 2
The charge stored in 1 escapes from the transparent electrode 24 through the portion of the photoconductive layer 23 where the resistance value has decreased. Therefore, the potential of the data electrode 21 corresponding to a portion where the imaging target is not in contact changes. That is, the data electrodes D6, D
7, and the potential of D8 changes.

The control unit 50 includes an address light guide A
A voltage application signal is output to the address driver circuit 30 so that light is incident on the data line 3, and a detection signal indicating that the potential of the data electrodes D6, D7, and D8 has dropped is received from the data line signal read circuit 40. Therefore, for example, the control unit 50 outputs (A3, D6), (A3,
The points (points a, b, and c in FIG. 4) corresponding to the portion where the object does not exist can be stored as data as D7) and (A3, D8).

When light is incident on the address light guide path A11, a point corresponding to a portion where the object is not in contact (FIG. 4,
(Circled points) are stored as data.

Using this data, for example, the X-coordinate of D1 to D13 of the data electrode and the Y-coordinate of A1 to A11 of the address light guide path, the circled point in FIG. 4 becomes as shown in FIG. Will be reproduced. In the re-development, by increasing the number of the address light guide paths 2 and the data electrodes 21 and increasing the number of points, the image of the object can be represented more accurately. The number of the address light guide path 2 and the number of the data electrodes 21 are as follows.
It is determined by an experiment or the like according to the purpose of imaging.

As described above, if the address light guide path 2 and the data electrode 21 are set according to the purpose, and the anode electrode 11 and the light shielding layer 22 are finely processed accordingly, the photoconductive layer 2
3. There is no need to pattern the transparent electrode 24, the organic EL layer 12, and the cathode electrode 13. Further, it is not necessary to use a high melting point glass for the substrate 1, and the imaging unit 2
0 production costs can be reduced.

Further, as described above, since the light emitted by the organic EL layer 12 is irradiated on the object to be imaged through the address light guide path 2, there is no need to use a right-angle prism or the like, and the entire photosensor is used. It can be made thin.

The shape of the object obtained as described above is stored in advance in a memory or the like as data, and it is determined whether or not the shape of the object obtained by imaging matches the data in the memory. You can also. This is, for example,
It can be applied to fingerprint collation.

Next, a photo sensor according to a second embodiment of the present invention will be described.

In this photo sensor, the address sequential EL light emitting unit 10 of the photo sensor shown in the first embodiment is
The configuration is such that it faces the imaging unit 20 with the substrate interposed therebetween.

FIG. 6 is a diagram showing the structure of this photosensor. FIG. 6A is a plan view of the photosensor as viewed from above. FIG. 6B shows the photosensor of FIG.
3 shows a cross-sectional structure when cut at B. FIG.
(C) shows a cross-sectional structure when the photosensor of (a) is cut by CC. In the figure, the same reference numerals as those in FIG. 1 indicate the same as those in FIG.

This photosensor is largely different from the photosensor shown in the first embodiment in that it does not use an address light guide path, uses a louver substrate 4, and is different from a surface on which an image pickup section 20 is formed. On the surface, an anode electrode 11 ', an organic EL layer 12', a cathode electrode 13 ', and a sealing film 14'
The address sequential EL light-emitting portion 10 ′ is formed.

The louver substrate 4 has a light guide portion 4a provided along the anode electrode 11 'and having a high transmittance for address light, and a reflection portion 4b having high reflectivity for the address light on both sides of the light guide portion 4a. Having. Accordingly, the light incident from the predetermined anode electrode 11 ′ out of the plurality of light is incident only on a predetermined one of the plurality of light guides 4 a of the louver substrate 4, and passes through only the light guide 4 a as it is to form the photoconductive layer. The light travels straight toward the light guide layer 23 or is repeatedly reflected by the reflector 4b so that the traveling direction is controlled substantially in the straight travel direction, and then the light is emitted from the light guide 4a toward the photoconductive layer 23.

Voltage is sequentially applied to the plurality of anode electrodes 11 'one by one, as in the first embodiment. As shown in FIG. 6, the anode electrodes 11 'are formed substantially parallel to each other so as to be substantially orthogonal to the data electrodes 21.

The light emitted from the organic EL layer 12 ′ by applying a predetermined voltage to the anode electrode 11 ′ is reflected between the reflection portions 4 b of the louver substrate 4 and does not leak to the next. The function substantially the same as that of the address light guide path 2 is performed.

The functions and operations of the other parts, the driving system and the imaging method are substantially the same as those shown in the first embodiment.

As described above, if the organic EL layer 12 ′ and the data electrode 21 are set according to the purpose and the anode electrode 11 ′ and the light-shielding layer 22 are finely processed, the photoconductive layer 23, the transparent electrode 24, there is no need to pattern the organic EL layer 12 'and the cathode electrode 13'. Further, it is not necessary to use a high-melting glass for the substrate, and the production cost of the photosensor can be reduced.

As described above, the organic EL layer 12 ′
Since the light emitted by the light source is directly applied to the object to be imaged, there is no need to use a right-angle prism or the like, and the entire photosensor can be configured to be thin.

The present invention is not limited to the first and second embodiments described above, and various modifications and applications are possible. Hereinafter, modifications of the above-described embodiment applicable to the present invention will be described.

In the address light guide 2 shown in the first embodiment, a groove or the like may be formed in the substrate, and this groove may be used as the light guide.

The photoconductive layer 23 has an island shape depending on the pixel (the intersection between the address light guide path 2 or the anode electrode 11 ′ and the data electrode 21) or is narrower than the data electrode 21 as shown in FIG. It may be formed in a line with a width. In this case, the light that enters the photoconductive layer 23 from the address light guide path 2 is blocked by the data electrode 21,
The light shielding layer 22 can be omitted. In this case, the photoconductive layer 2
3 is formed of an interlayer insulating resin 27 that transmits light.

Further, the protective film 25 may be a thin film. In this case, the photoconductive layer 23 becomes strong against the external environment.

The transparent electrode 24 and the cathode electrode 13
May be formed in the same pattern so as to correspond to the data electrode 21 and the anode electrode 11, respectively, instead of one sheet. Further, the transparent electrode 24 is formed of a pixel (an intersection between the address light guide path 2 or the anode electrode 11 ′ and the data electrode 21).
May be formed only at the position corresponding to.

The substrate (louver substrate 4) shown in the second embodiment may be a glass substrate provided with a louver substrate, or may be a substrate obtained by cutting out an optical fiber plate in place of the louver substrate. The optical fiber plate has a light-reflective honeycomb shape in a state in which a plurality of transparent fibers are bundled in a longitudinal direction substantially equal to a direction of a shortest line connecting the anode electrode 11 ′ and the photoconductive layer 23. And is set such that light incident from the anode electrode 11 ′ proceeds toward the photoconductive layer 23.

The photosensor is provided with a photoconductive layer 2 based on the difference in the amount of reflected light incident on the photoconductive layer 23 of the imaging section 20.
Since the change in the resistance value of 3 is used, the object to be imaged is
Not only an object having irregularities such as a fingerprint but also an object having a different reflectance may be used. For example, in an image written in black on white paper, the reflectance of the white portion is different from that of the black portion, so that the image can be read by the above method.
Therefore, the photo sensor described above can also be used as a scanner.

Further, in the above-described photosensor, when the photoconductive layer 23 whose resistance value gradually changes with respect to the incidence of light is used, and the temporal change of the resistance value with respect to the amount of incident light is known in advance. Can read the gray scale of the imaging target by measuring the potential of the data electrode 21 with time. Further, when such a material can be applied to the photoconductive layer 23, if the data electrode 21 has a non-transmissive property with respect to light, such as carbon black, the data electrode 21 can also serve as the light shielding layer 22.

Further, the image pickup unit 2 shown in the first embodiment
No. 0 indicates that the transparent electrode 24 and the photoconductive layer 23 are sequentially laminated on the substrate 1 and the data electrode 21 and the photoconductive layer 23 are formed on the photoconductive layer 23.
The light shielding layer 22 may be formed, and the protective film 25 may be laminated thereon. In this case, light is incident from the protective film 25 in the direction of the substrate 1 so that the object to be imaged contacts the surface of the substrate 1.

[0096]

As is apparent from the above description, according to the present invention, it is not necessary to use a right-angle prism in an imaging device. Further, there is no need to perform complicated patterning on the light emitting layer and the conductive layer.

Therefore, it is possible to provide an image pickup device which performs good image pickup and reduces production cost.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a configuration of an image capturing unit and an address sequential EL light emitting unit of a photo sensor according to a first embodiment.

FIG. 2 is a diagram illustrating a drive system of an imaging unit and an address sequential EL light emitting unit.

FIG. 3 is a diagram illustrating a state in which an image of an imaging target is being captured;

FIG. 4 is a diagram for explaining an operation when reading an imaging target.

FIG. 5 is a diagram showing a state in which data of an image is reproduced.

FIG. 6 is a diagram illustrating a configuration of a photosensor according to a second embodiment.

FIG. 7 is a diagram illustrating another configuration of the photoconductive layer of the imaging unit.

FIG. 8 is a diagram illustrating a configuration example of a conventional imaging device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Substrate, 2 ... Address light guide path, 4 ... Louver board, 4a ... Light guide part, 4b ... Reflection part, 10 ... Address sequential EL light emission part, 11 ... Anode electrode, 12 ... Organic E
L layer, 13: cathode electrode, 14: sealing film, 10 '
・ Address sequential EL light emitting section, 11 ′...
2 '... organic EL layer, 13' ... cathode electrode, 14 '...
・ Sealing film, 20 ・ ・ ・ Imaging unit, 21 ・ ・ ・ Data electrode, 22 ・ ・ ・
Light-shielding layer, 23 ... Photoconductive layer, 24 ... Transparent electrode, 25 ...
Protective film, 27: interlayer insulating resin, 30: address driver circuit, 40: data line signal readout circuit, 50: control unit, 60: right angle prism, 6
0a: Total reflection film, 61: Light source, 62: Lens, 63: CCD, FG: Finger

Claims (3)

[Claims] 1. A plurality of light guides formed to be substantially parallel to each other and separated from each other to guide incident light; and an applied voltage formed corresponding to a part of each of the plurality of light guides. A plurality of light emitting elements that emit light in accordance with and guide light to each of the plurality of light guide paths; and a plurality of light emitting elements that are spaced apart from each other and substantially parallel to each other and form a predetermined angle with the plurality of light guide paths. A plurality of first electrodes formed at positions where elements are not formed; and a layer formed by laminating the first electrodes at least at intersections of the plurality of light guide paths and the plurality of first electrodes. A photoconductive layer whose resistance changes when light in a predetermined wavelength range is incident thereon; and a light blocking means for blocking light such that light emitted from the light guide path is not directly incident on the photoconductive layer. Corresponding to the position where the photoconductive layer is formed. First electrode and opposite to the imaging device, characterized in that and a second electrode formed by laminating the photoconductive layer. 2. The imaging device according to claim 1, wherein the light emitting element and the photoconductive layer are arranged so as not to overlap each other in a layer thickness direction. 3. The light-blocking means, wherein the plurality of first electrodes are made of a material having light non-transmissivity, and are formed between the photoconductive layer and the plurality of light guide paths. The image pickup device according to claim 1, wherein the image pickup device also functions as: