JP2001285573A - Image information read method and device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a radiation solid-state detector, where a ray emission linear electrode and a charging linear electrode are placed in parallel, and that can surely increase signal charge amounts, using a simple configuration. SOLUTION: The detector 20 consists of a recording light side electrode layer 21, recording optical conductive layer 22, charge carrying layer 23, reading optical conductive layer 24 and read light side electrode layer 25, having a stripe electrode 26 comprising an element 26a, which are layered in this order. A charging element 27a for providing an output of an electric signal with a level in response to the quantity of latent image polarity electric charges which are stored in a storage section 29 formed on a border surface between the recording optical conductive layer 22 and the charge-carrying layer 23, is placed in parallel with the element 26a. A planar light source 30, consisting of an electrode layer 31, an EL layer 32 provided with an EL material 32a and an electrode layer 33 so as to correspond to only each light emission element 26a is integrally provided so as to face the read light side electrode layer 25.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a recording photoconductive layer,
The present invention relates to an image information reading method and apparatus using an optical reading type image detector including a reading photoconductive layer, a power storage unit, and a stripe electrode having transparency to reading electromagnetic waves.

[0002]

2. Description of the Related Art Conventionally, apparatuses using an image detector, such as a facsimile, a copying machine, and a radiation imaging apparatus, are known.

For example, in a medical radiation imaging apparatus or the like, a photoconductive material such as a selenium plate which exhibits conductivity in response to radiation such as X-rays is used in order to reduce the exposure dose received by a subject and improve diagnostic performance. An optical readout radiation solid state detector (electrostatic recording medium) having a body (layer) is used as an image detector, and the radiation solid state detector is irradiated with X-rays as recording electromagnetic waves (hereinafter also referred to as recording light). And the amount of charge (charge pair) corresponding to the dose of irradiated X-rays generated in the photoconductor
The radiographic image information is recorded as an electrostatic latent image by accumulating the latent image polar charge (latent image charge) in the power storage unit in the solid-state radiation detector, and is read as electromagnetic waves for reading (hereinafter also referred to as reading light). The signal light corresponding to the polarity charge of the latent image is read out by scanning the reading light side electrode layer of the solid-state radiation detector on which the radiation image information is recorded with the laser beam or the line light, that is, the current corresponding to the signal charge is detected. For example, a method of reading radiation image information is known (for example, US Pat. No. 5,268,569, International Publication 199).
No. 59261, JP-A-9-5906, and Japanese Patent Application Nos. 10-271374 and 11-8792 filed by the present applicant.
No. 2 and No. 11-89553).

[0004] Here, Japanese Patent Application No. 10-2 filed by the present applicant.
The radiation solid state detector described in, for example, Japanese Patent No. 71374 refers to a recording light-side electrode layer (first electrode layer) having transparency to recording light, and receiving irradiation of recording light transmitted through the recording light-side electrode layer. The recording photoconductive layer, which exhibits electrical conductivity by generating an electric charge, acts as a substantially insulator for a latent image polarity electric charge having the same polarity as the electric charge charged on the recording light side electrode layer, and the latent image polarity A charge transport layer that acts as a substantially conductive substance for a transport polarity charge (transport charge) having a polarity opposite to that of the charge, a read photoconductive layer that exhibits conductivity by generating a charge when irradiated with read light, and a read A reading light side electrode layer (second electrode layer) having transparency to light is laminated in this order, and a power storage unit is formed at the interface between the recording photoconductive layer and the charge transport layer.

[0005] The applicant of the present invention has disclosed the above-mentioned Japanese Patent Application No. 10-271.
No. 374, etc., one of the methods for reading out signal charges is to form a linear electrode on a reading light side electrode layer for obtaining an electric signal corresponding to the amount of the latent image polar charge as a light irradiation electrode. A plurality of electrodes are arranged in a stripe shape to form a stripe electrode (comb electrode), and a detection amplifier is connected to each linear electrode. The longitudinal direction of the linear electrode is defined as a sub-scanning direction, the longitudinal direction of the linear electrode is defined as A direction orthogonal to the array direction (the arrangement direction of the linear electrodes) is defined as a main scanning direction, and the stripe electrode side is scanned in a sub-scanning direction by linear read light (hereinafter also referred to as line light) extending in the main scanning direction. A method of detecting a signal charge for each linear electrode (hereinafter, referred to as a line reading method) has been proposed.

In this line reading method, the reading speed is increased because the reading is performed in parallel (simultaneous) in the main scanning direction, and the distributed capacitance of each detection amplifier is obtained by dividing the electrodes into linear electrodes. Since the (load capacity) is reduced, the S / N ratio can be improved. Further, since the storage position of the latent image polar charge can be fixed at least at the position where the linear electrodes are provided, the structure-noise correction is performed. It is an excellent method having various advantages, such as the ability to perform the following.

[0007] The applicant of the present invention has disclosed the aforementioned Japanese Patent Application No. 11-879.
In JP-A Nos. 22 and 11-89553, in order to improve reading efficiency, a sub-element (charge) is arranged in parallel with each linear electrode forming a stripe electrode (hereinafter referred to as a linear electrode for light irradiation) in a reading light side electrode layer. Extraction linear electrode)
Is arranged as a charging linear electrode, a detector that can use the charging linear electrode when outputting an electric signal according to the amount of the latent image polar charge stored in the power storage unit. is suggesting.

When the charging linear electrodes are provided in this manner, a new capacitor is formed between the power storage unit and each charging linear electrode, and has a polarity opposite to that of the latent image polar charge stored in the power storage unit by recording. Can be charged on the charging linear electrode by charge rearrangement at the time of reading. With this, the amount of the transport charge distributed to the capacitor formed between the linear electrode for light irradiation and the power storage unit via the photoconductive layer for reading is made relatively smaller than the case where the linear electrode for charging is not provided. In addition to increasing the amount of signal charges that can be extracted from the detector to the outside, the reading efficiency is improved, and at the same time, the effect of providing a stripe electrode such as high-speed response of reading is also achieved. You can do it.

Further, the applicant of the present application has disclosed the above-mentioned Japanese Patent Application No. 11-20 / 1990.
In No. 7283, even when a linear electrode for charging is provided, if the transmittance of the linear electrode for light irradiation to reading light is small, the linear electrode for light irradiation functions as a light irradiation electrode. When the transmittance decreases or the transmittance of the charging linear electrode with respect to the reading light is large, the charging linear electrode also functions as a light irradiation electrode and the amount of signal charge that can be taken out may be reduced. To ensure that the amount of light incident on the photoconductive layer for light irradiation from the linear electrode portion for light irradiation is larger than the amount of light incident from the linear electrode portion for charging, the transmittance of both linear electrodes to the reading light and It has also been proposed to define a conditional expression regarding the width of the electrode so as to surely improve the reading efficiency.

[0010]

However, in order to satisfy a predetermined conditional expression, the members of the linear electrode for light irradiation and the linear electrode for charging must usually be made different from each other, and the electrode structure is not sufficient. It becomes complicated, and these different components
It is difficult to form a film on one electrode layer, and even if it can be realized, the manufacturing process becomes complicated and the cost increases.

The present invention has been made in view of the above circumstances, and provides an image detector that has a simple electrode structure and can be easily manufactured when a charging linear electrode is provided to improve reading efficiency. It is intended to provide.

[0012]

SUMMARY OF THE INVENTION The present invention provides a light source configured to irradiate reading light only to a linear electrode for light irradiation and not to irradiate a linear electrode for charging. Is characterized in that the light irradiation linear electrode and the charging linear electrode can be made of the same material and the same structure. That is, the image information reading method according to the present invention includes a recording photoconductive layer that generates a latent image polar charge by being irradiated with a recording electromagnetic wave and exhibits conductivity, and a charge that is irradiated with the reading electromagnetic wave. A photoconductive layer for reading, which exhibits conductivity, and two electrode layers provided so as to sandwich the two photoconductive layers for applying an electric field to the two photoconductive layers; and a photoconductive layer for recording. And a power storage unit for storing a latent image polarity charge formed between the photoconductive layer and the reading photoconductive layer, wherein the electrode layer on the reading photoconductive layer side of the two electrode layers is used for reading electromagnetic waves for reading. A large number of linear electrodes for light irradiation and a plurality of linear electrodes for charging for outputting an electric signal corresponding to the amount of the latent image polar charges are arranged in parallel to each other, and are read. Scanning the electrode layer on the photoconductive layer side for reading In a method of reading image information using an optical reading type image detector that outputs a current corresponding to the amount of the latent image polar charge for each light irradiation linear electrode, a reading linear line for charging an electromagnetic wave is used. The irradiation intensity on the electrode is made smaller than the irradiation intensity of the electromagnetic wave for reading on the linear electrode for light irradiation.

In the image information reading method of the present invention, the irradiation intensity of the reading electromagnetic wave to the charging linear electrode is 1/5 or less of the irradiation intensity of the reading electromagnetic wave to the light irradiation linear electrode. It is desirable to be.

An image information reading apparatus according to the present invention is an apparatus for performing the above method, that is, a recording photoconductive layer which exhibits a conductivity by generating a latent image polarity charge by being irradiated with an electromagnetic wave for recording. A reading photoconductive layer that exhibits electrical conductivity by generating charges by being irradiated with reading electromagnetic waves,
Two electrode layers provided so as to sandwich the two photoconductive layers for applying an electric field to the two photoconductive layers, and a latent image formed between the recording photoconductive layer and the reading photoconductive layer A power storage unit for accumulating polar charges, wherein the electrode layer on the reading photoconductive layer side of the two electrode layers is connected to a light irradiation linear electrode having transparency to electromagnetic waves for reading and a latent electrode. A large number of charging linear electrodes for outputting an electric signal corresponding to the amount of the image polarity charges are arranged in parallel with each other, and the scanning electromagnetic wave scans the electrode layer on the reading photoconductive layer side. Accordingly, an optical reading type image detector for outputting a current corresponding to the amount of the latent image polar charge for each of the light irradiation linear electrodes, and an image signal carrying image information by detecting the current are obtained. Scanning means for scanning the electrode layer on the photoconductive layer side for reading with an electromagnetic wave for reading; In the image information reading apparatus, the irradiation intensity of the reading electromagnetic wave to the charging linear electrode is smaller than the irradiation intensity of the reading electromagnetic wave to the light irradiation linear electrode. And a light source having the above configuration.

In the image information reading apparatus according to the present invention, the light source may be configured such that the irradiation intensity of the reading electromagnetic wave to the charging linear electrode is 1 / th of the irradiation intensity of the reading electromagnetic wave to the light irradiation linear electrode. It is desirable that the number be 5 or less.

[0016]

According to the image information reading method and apparatus of the present invention, the irradiation intensity of the reading electromagnetic wave to the charging linear electrode is higher than the irradiation intensity of the reading electromagnetic wave to the light irradiation linear electrode. Since the charging linear electrode and the light irradiating linear electrode are made of the same material and have the same structure, the charging linear electrode can be made to be a photocharge non-generating electrode. The manufacture of a good detector becomes easier.

[0017] Further, by taking measures on the light source side, it is not necessary to perform a special treatment on the charging linear electrode, and the manufacturing process of the detector is not complicated, and there is no problem of an increase in cost.

Further, when the width and the transmittance of the linear electrode for light irradiation and the width and the transmittance of the linear electrode for charging satisfy a predetermined conditional expression, the reading efficiency is further improved. Can be done.

[0019]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an image information reading apparatus (hereinafter, also simply referred to as a reading apparatus) of the present invention, in which a solid-state radiation detector as an image detector, a light source, and a current detection circuit as an image signal acquiring means are integrally formed. 1 (A) is a perspective view of a detector, FIG. 1 (B) is an XZ sectional view of an arrow P portion of FIG. 1 (A), and FIG. 1 (C). FIG. 2 is an XY cross-sectional view of the Q arrow finger part of FIG. In FIG. 1A, a part of a recording device (such as a power supply) for recording an electrostatic latent image on a detector 20, a light source control means 40 for controlling a planar light source 30 for reading, and a current detection circuit 5
0 is also shown.

First, a radiation solid state detector 20 as an image detector used in the image information reading method and apparatus of the present invention will be described.

The solid-state radiation detector 20 has a recording-light-side electrode layer 21 that is permeable to recording light carrying image information such as X-rays transmitted through a subject, and has passed through the recording-light-side electrode layer 21. The recording photoconductive layer 22 which generates a charge pair by receiving the recording light and exhibits conductivity, and acts as a substantially insulator with respect to a latent image polar charge (for example, a negative charge) in the charge pair; In addition, the charge transport layer 23, which acts as a substantially conductive material, with respect to a transport polarity charge having a polarity opposite to that of the latent image (positive charge in the above example), generates a charge pair by being irradiated with the reading light. And a reading photoconductive layer 24 exhibiting electrical conductivity, and a reading light side electrode layer 25 having transparency to reading light are arranged in this order. At the interface between the recording photoconductive layer 22 and the charge transport layer 23, a two-dimensionally distributed power storage unit 29 for storing latent image polar charges carrying image information generated in the recording photoconductive layer 22 is formed. You.

The size (area) of the detector 20 is, for example, not less than 20 × 20 cm, and particularly in the case of chest X-ray photography, the effective size is about 43 × 43 cm.

The material of the recording photoconductive layer 22 is a-
Lead (II) such as Se (amorphous selenium), PbO, PbI ₂ , lead (II) iodide, Bi ₁₂ (Ge, S
_i) O 20, _Bi 2 photoconductive material containing as a main component at least one of such _{I 3} / organic polymer nanocomposite is appropriate.

As the substance of the charge transport layer 23, for example, the larger the difference between the mobility of the negative charge charged to the recording light side electrode layer 21 and the mobility of the positive charge having the opposite polarity, the better (for example, 10 ^2). or more, preferably 10 ³ or higher) poly N- vinylcarbazole (PVK), N, N'-diphenyl -N, N '
-Bis (3-methylphenyl)-[1,1'-biphenyl]
Organic compounds such as -4,4'-diamine (TPD) and discotic liquid crystal, or TPD polymer (polycarbonate, polystyrene, PUK) dispersion, Cl
Semiconductor materials such as a-Se doped with ~ 200 ppm are suitable. In particular, organic compounds (PVK, TPD, discotic liquid crystal, and the like) are preferable because they have photosensitivity, and the charge transport layer 23 is generally low in dielectric constant.
Thus, the capacity of the reading photoconductive layer 24 is reduced, and the signal extraction efficiency at the time of reading can be increased. Here, “having light insensitivity” means that the material hardly exhibits conductivity even when irradiated with the recording light L1 or the reading light L2.

The material of the reading photoconductive layer 24 is a-
Se, Se-Te, Se-As-Te, metal-free phthalocyanine, metal phthalocyanine, MgPc (Magnesium ph
talocyanine), VoPc (phase II of Vanadyl phthal)
Preferred is a photoconductive material containing at least one of ocyanine), CuPc (Cupper phtalocyanine) and the like as a main component.

The thickness of the recording photoconductive layer 22 should be 50 μm or more and 1000 μm in order to sufficiently absorb the recording light.
It is preferably not more than μm.

The charge transport layer 23 and the read photoconductive layer 24
Is preferably not more than の of the thickness of the recording photoconductive layer 22, and the thinner the better, the better the response at the time of reading. Is preferably 1/100 or less.

The material of each of the above layers is such that the recording light side electrode layer 21 is charged with a negative charge and the reading light side electrode layer 25 is charged with a positive charge, so that the interface between the recording photoconductive layer 22 and the charge transport layer 23 is formed. A negative charge as a latent image polar charge is accumulated in the power storage unit 29 formed in the first and second layers, and the charge transport layer 23 is formed as a transport polarity charge having a polarity opposite to that of the negative charge mobility as the latent image polar charge. The mobility of the positive charge is larger, which is an example of a material that is suitable for functioning as a so-called hole transport layer.However, these may each be a charge of the opposite polarity, and thus the polarity is reversed. At this time, only a slight change such as changing the charge transport layer functioning as the hole transport layer to the charge transport layer functioning as the electron transport layer is sufficient.

For example, a photoconductive substance such as the above-described amorphous selenium a-Se, lead oxide (II), and lead (II) iodide can be used for the recording photoconductive layer 22. -Trinitrofluorenylidene aniline (TNFA) dielectric, trinitrofluorenone (TNF) /
A polyester dispersion system and an asymmetric diphenoquinone derivative are suitable, and the above-mentioned non-metallic phthalocyanine and metal phthalocyanine can be similarly used as the reading photoconductive layer 24.

In the detector 20, the power storage unit 29 is formed at the interface between the recording photoconductive layer 22 and the charge transport layer 23. However, the present invention is not limited to this. For example, US Pat. As described above, the power storage unit may be formed by the trap layer that stores the latent image polarity charge as a trap.

The recording-light-side electrode layer 21 and the reading-light-side electrode layer 25 only need to have transparency to recording light or reading light, respectively. Include a Nesa film (SnO ₂ ) known as a light transmitting metal thin film, and ITO (Indium Tin Oxi).
de) or IDIXO (Idemitsu Indium X-me), which is an amorphous light-transmitting metal oxide that is easy to etch
metal oxides such as tal Oxide; Idemitsu Kosan Co., Ltd.
It can be used with a thickness of about 200 nm, preferably 100 nm or more. In addition, aluminum Al, gold Au,
Pure metal such as molybdenum (Mo) and chromium (Cr)
By setting the thickness to 0 nm or less (preferably about 10 nm), transparency to visible light can be imparted. By using any of these, the transmittance for visible light as reading light can be made 50% or more.

When an image is recorded by using X-rays as the recording light and irradiating the X-rays from the recording light-side electrode layer 21 side, the recording light-side electrode layer 21 has transparency to visible light. Since the recording light side electrode layer 21 is unnecessary, a pure metal such as Al or Au having a thickness of, for example, 100 nm can be used.

On the other hand, the light irradiation electrode of the reading light side electrode layer 25 is a stripe electrode 26 in which a number of elements (linear electrodes) 26a are arranged in a stripe pattern at a pixel pitch. The pixel pitch is set to about 50 to 250 μm in order to enable high S / N while maintaining high sharpness in medical X-ray imaging. Further, within the range of the pixel pitch, the width of each element 26a is set to 10 to 200
It is about μm.

Here, the purpose of using the electrodes of the reading light side electrode layer 25 as the stripe electrodes 26 is to simplify the correction of the structure noise or to reduce the capacitance of the image by reducing the capacitance.
/ N, or by localizing the electrostatic latent image corresponding to the stripe electrodes to increase the electric field strength, improve the reading efficiency and improve the S / N, and perform parallel reading (mainly in the main scanning direction). ) To shorten the reading time.

In the reading light side electrode layer 25, a level corresponding to the amount of the latent image polarity charge stored in the power storage unit 29 formed at the substantially interface between the recording photoconductive layer 22 and the charge transport layer 23 is provided. Is provided with a charging electrode 27 which is a conductive member for outputting the electric signal. The charging electrode 27 has a large number of charging elements (charging linear electrodes) 27a arranged in a stripe pattern.
7a are arranged such that the charging elements 27a and the elements 26a of the stripe electrodes 26 are alternately arranged in parallel.

A predetermined distance is maintained between each element 26a and each charging element 27a so as to be electrically insulated, and a slight amount of pigment such as carbon black is dispersed between the two elements 25a. It is filled with a non-conductive polymer material such as polyethylene, and has a light shielding property with respect to reading light.

The charging element 27a of the charging electrode 27
The material and thickness of the electrode material forming the same are the same as those of the electrode material forming the element 26a of the stripe electrode 26. As a result, the stripe electrode 26 and the charging electrode 27 are made of the same material and arranged in the same structure (thickness). Just make it different.

In this detector 20, _a capacitor C _{* a} is formed between the recording light-side electrode layer 21 and the power storage unit 29 with the recording photoconductive layer 22 interposed therebetween, and the charge transport layer 23 and the reading photoconductive layer A capacitor C _{* b is provided} between the power storage unit 29 and the stripe electrode 26 (element 26a) with the layer 24 interposed therebetween.
Are formed, and the reading photoconductive layer 24 and the charge transport layer 23 are formed.
, A capacitor C _{* c} is formed between the power storage unit 29 and the charging electrode 27. At the time of charge rearrangement at the time of reading, the amount of positive charge Q _{+ a} , Q _{+ b} , Q _{+ c} distributed to each of the capacitors C _{* a} , C _{* b} , C _{* c} is such that the total Q ₊ is the latent image polarity charge. the amount Q _- the same as the capacitance of the capacitors C
_a, a _C b, an amount proportional to _{C c.} This can be represented by the following equation.

[0039] _{Q - = Q + = Q +} a + Q + b + Q + c Q + a = Q + × C a / (C a + C b + C c) Q + b = Q + × C b / (C a + C b + C c) Q _{+ C} = Q _{+ Cc} / ( _Ca + _Cb + _Cc ) The amount of signal charge that can be extracted from the detector 20 is the amount of positive charge Q _{+ a} , distributed to the capacitors C _{* a} and C _{* c} .
The sum is equal to the sum of Q _{+ c} (Q _{+ a} + Q _{+ c} ), and the positive charge distributed to the capacitor C _{* b} cannot be taken out as a signal charge (for details, refer to Japanese Patent Application No. 11-87922).

Here, the stripe electrode 26 and the charging electrode
Capacitor C with pole 27_{* B}, C _{* C}About the capacity of
Considering that, the capacity ratio C_b: C_cRepresents each element
26a, 27a width ratio W_b: W_cBecomes on the other hand,
Capacitor C_{* A}Capacity C_a And capacitor C_{* B}Capacity
C_bMeans that even if the charging electrode 27 is provided,
No sound appears.

As a result, during charge rearrangement at the time of reading, the amount of positive charge Q _{+ b} distributed to the capacitor C _{* b} can be made relatively smaller than when the charging electrode 27 is not provided. To that extent, the amount of signal charge that can be extracted from the detector 20 via the charging electrode 27 is reduced.
Can be relatively larger than the case without
It is possible to reliably improve the reading efficiency and the S / N of the image.

The detector 20 is connected to the current detection circuit 50 and is formed integrally with the planar light source 30. The planar light source 30 is a light source control unit 4 for controlling the planar light source 30.
0 is connected.

The current detection circuit 50 reads out the charge corresponding to the latent image polarity charge stored in the power storage unit 29 via the charging electrode 27, thereby obtaining an image signal of a level corresponding to the amount of the latent image polarity charge. And has a large number of detection amplifiers 51 connected to each element 26a of the stripe electrode 26. The detection amplifier 51 is connected to each element 27a.
Is used as a charging electrode to detect as a current an amount of charge corresponding to the amount of the latent image polarity charge.
1a, an integrating capacitor 51b and a switch 51c.

The recording-light-side electrode layer 21 of the detector 20 is connected to one of the inputs 54 a and 55 a of the switches 54 and 55 and the negative electrode of the power supply 52. The positive pole of the power supply 52 is connected to the negative pole of the power supply 53 and the other input 55 of the switch 55.
b. The positive electrode of the power supply 53 is connected to the other input 54b of the switch 54. Each operational amplifier 51
The non-inverting input terminal (+) of a is commonly connected to the output of the switch 54, and the inverting input terminal (-) is individually connected to the element 26a. The output of the switch 55 is commonly connected to each element 27a of the charging electrode 27.

The planar light source 30 is entirely composed of an EL luminous body, and has an electrode layer 31, an EL layer (light emitting layer) 32, and an electrode layer 33. An insulating layer 34 is provided between the reading light side electrode layer 25 of the detector 20 and the electrode layer 31 of the planar light source 30. The electrodes of the electrode layer 31 have a large number of light-transmissive elements (linear electrodes) 31a (hatched portions in the drawing) arranged in a stripe shape so as to intersect (substantially orthogonal in this example) the elements 26a of the detector 20. It consists of On the other hand, the electrode of the electrode layer 33 is made of a support 3 such as a glass substrate.
5 is a flat plate electrode formed on the substrate 5 and totally reflects the EL light emitted from the EL layer 32. ITO or IDIXO is used as the element 31a.
Each element 31a is connected to the light source control means 40.

The EL layer 32 may be an inorganic EL layer formed of an inorganic material or an organic EL layer formed of an organic material.
It may be an L layer. In the EL layer 32, the EL material is not uniformly filled in the entire layer, but only the portions 32a corresponding to the light irradiation elements 26a of the detector 20 are filled with the EL material. A portion 32b corresponding to each of the elements 27a is filled with a light blocking member.

The light source control means 40 controls each element 31a.
Are sequentially switched, a predetermined DC voltage is applied between each element 31a and the electrode layer 33. By applying the DC voltage, EL light is emitted from a portion of the EL layer 32 sandwiched between the element 31a and the electrode layer 33.

As described above, in the EL layer 32, only a portion 32a corresponding to each of the light irradiation elements 26a is filled with the EL material.
Is in close contact with the detector 20 via an extremely thin insulating layer 34, so that even if a voltage is applied between the linear (linear) element 31a and the electrode layer 33, the portion filled with the EL material The EL light emitted from 32a is transmitted through the element 31a so as to irradiate only the light irradiating element 26a with little spread. Accordingly, when the irradiation intensity of the reading light on the element 26a is U _b and the irradiation intensity on the sub-element 27a is U _c , U _b / U
_c ≧ 5 is surely satisfied.

That is, as the planar light source 30, a large number of small point light sources comprising an element 31a, an EL layer 32 (particularly, an EL filling portion 32a) and an electrode layer 33 are provided in a planar manner as shown by hatching in FIG. By arranging the elements 31a sequentially in the longitudinal direction of the light irradiation elements 26a to emit EL light from the EL layer 32,
EL corresponding only to each of the light irradiation elements 26a
It becomes possible to electrically scan the radiation solid state detector 30 with light (reading light).

As a result, the sub-element 27a is not irradiated with the reading light, and the charging sub-element 2
The problem that the reading efficiency decreases due to the edge effect of 7a does not occur.

Further, since the sub-element 27a is not subjected to special processing by taking measures on the light source side, the manufacturing process on the detector side is not complicated, and there is no problem of cost increase.

Further, since the reading light is not applied to the charging electrode and the reading light is applied only to the light irradiation electrode, even if the light irradiation electrode and the charging electrode are made of the same material and have the same structure. This makes it easier to manufacture a detector with good reading efficiency.

Further, when the width and the transmittance of the linear electrode for light irradiation and the width and the transmittance of the linear electrode for charging satisfy a predetermined condition, the reading efficiency is further improved. Can be done.

In the above embodiment, the electrode layer 33, the EL layer 32, the element 31a, and the insulating layer 3
4 are arranged in this order to form the planar light source 30 and the insulating layer 34.
Are integrally formed facing the detector 20, but this is not necessarily required. For example, as shown in FIG. 2, a structure in which a support 35 such as a glass substrate is interposed between the planar light source 30, the electrode layer 33, the EL layer 32, and the element 31a may be employed.

In the embodiment shown in FIG.
0 can be brought close to the light irradiation element 26a, so that no special means for condensing the EL light emitted from the EL layer 32 is required. There is a possibility that the EL light emitted from the portion 32a filled with the EL material expands when passing through the support 35 and irradiates not only the light irradiation element 26a but also the charging sub-element 27a. . Therefore, when such a configuration is adopted, a dielectric mirror 36 as an optical resonator structure is formed by laminating dielectric multilayer films,
The spread width of the EL light emitted from the L layer 32 is reduced, and
The directivity of the L light is improved so that the EL light is irradiated only to the light irradiation element 26a.

The element 26 for irradiating the reading light is used.
The irradiation intensity for a_b, Charging sub-element 27
The irradiation intensity for a_c, The dielectric mirror 36
Is U _b/ U_cThe degree of light collection that satisfies ≧ 5
Just do it.

In the above-described embodiment, the minute EL emitters each having the light transmitting element 31a and emitting the linear EL light toward the detector 20 via the element 31a are distributed two-dimensionally. Although the disposed planar light source is configured integrally with the detector 20, the detector and the light source may be separate.

For example, each LED, LCD,
EL or laser diode etc. for each element 26
and a whole arranged in a line so as to face only a.
To form a linear light source, and dispose the light source separately from the detector.
The light source in the longitudinal direction of the element 26a.
26a.
No. In this case, the light source and the detector are separated by a certain distance.
The individual LEs facing each element 26a
Light emitted from D or the like is applied to the corresponding element 26a.
Only enters and does not irradiate the charging element 27a.
For example, the refractive index of, for example, Selfoc lens (trademark)
It is preferable to provide a condensing means using a distributed lens.
No. Irradiation of the reading light to the light irradiation element 26a
Strength is U_b Irradiation intensity on the charging sub-element 27a
Degree U_cAnd U_b/ U_cSatisfies ≧ 5
What is necessary is just a degree of light collection. The right side is preferable
Is more preferably 8, and more preferably 12.

[Brief description of the drawings]

FIG. 1 is a diagram showing an embodiment of an image information reading apparatus according to the present invention, in which a solid-state radiation detector serving as an image detector, a light source, and a current detection circuit are integrally formed, and FIG. (A) shown in the figure, XZ of the arrow P part of the figure (A)
Sectional view (B), XY section view (C) of Q arrow finger part of figure (A)

FIG. 2 is a plan view showing distribution of a planar light source.

FIG. 3 is a schematic view showing another embodiment of the light source.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Image information reading apparatus 20 Radiation solid state detector (image detector) 21 Recording light side electrode layer 22 Recording photoconductive layer 23 Charge transport layer 24 Reading photoconductive layer 25 Reading light side electrode layer 26 Stripe electrode 26a Light irradiation Element (light-emitting linear electrode) 27 charging electrode 27a charging element (charging linear electrode) 29 power storage unit 30 planar light source 31a element (linear electrode) 40 light source control means (drive source and EL light Function as scanning means) 50 current detection circuit (image signal acquisition means)

Claims (4)

[Claims] 1. A recording photoconductive layer, which generates a latent image polarity charge by being irradiated with a recording electromagnetic wave and exhibits conductivity, and generates a charge by being irradiated with a reading electromagnetic wave to be conductive. A reading photoconductive layer exhibiting a property, two electrode layers provided so as to sandwich the two photoconductive layers and applying an electric field to the two photoconductive layers, the recording photoconductive layer and the reading And a power storage unit for storing the latent image polarity charge formed between the photoconductive layer and the read photoconductive layer. A large number of light irradiation linear electrodes having transparency to electromagnetic waves and charging linear electrodes for outputting an electric signal corresponding to the amount of the latent image polar charge are arranged in parallel with each other. The electrode layer on the photoconductive layer side for reading is scanned by the electromagnetic wave for reading. A method for reading image information using an optical reading type image detector that outputs a current corresponding to the amount of the latent image polar charge to each of the light irradiation linear electrodes. An irradiation intensity of the electromagnetic wave to the linear electrode for charging is smaller than an irradiation intensity of the electromagnetic wave for reading to the linear electrode for light irradiation. 2. An irradiation intensity of the reading electromagnetic wave to the charging linear electrode is set to be not more than 1/5 of an irradiation intensity of the reading electromagnetic wave to the light irradiation linear electrode. 2. The image information reading method according to claim 1, wherein: 3. A recording photoconductive layer, which generates a latent image polarity charge by being irradiated with a recording electromagnetic wave and exhibits conductivity, and a charge generation is generated by being irradiated with a reading electromagnetic wave to be conductive. A reading photoconductive layer exhibiting a property, two electrode layers provided so as to sandwich the two photoconductive layers and applying an electric field to the two photoconductive layers, the recording photoconductive layer and the reading And a power storage unit for storing the latent image polarity charge formed between the photoconductive layer and the read photoconductive layer. A large number of light irradiation linear electrodes having transparency to electromagnetic waves and charging linear electrodes for outputting an electric signal corresponding to the amount of the latent image polar charge are arranged in parallel with each other. The electrode layer on the photoconductive layer side for reading is scanned by the electromagnetic wave for reading. An optical readout type image detector that outputs a current corresponding to the amount of the latent image polar charge for each of the linear electrodes for light irradiation, and an image signal that detects the current and carries image information. Obtaining image signal obtaining means;
A scanning unit for scanning the electrode layer on the reading photoconductive layer side with the reading electromagnetic wave, wherein the scanning unit transmits the reading electromagnetic wave to the charging linear electrode. An image information reading apparatus, comprising: a light source that makes the irradiation intensity of the electromagnetic wave for reading smaller than the irradiation intensity of the electromagnetic wave for reading on the linear electrode for light irradiation. 4. An irradiation intensity of the reading electromagnetic wave to the charging linear electrode, wherein the irradiation intensity of the reading electromagnetic wave to the charging linear electrode is 1/5 or less of an irradiation intensity of the reading electromagnetic wave to the light irradiation linear electrode. 4. The image information reading apparatus according to claim 3, wherein: