JP2003209236A - Imaging apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an imaging apparatus including a solid-state detector having a layer of a-Se contained as its main components, which can suppress the occurrence of an artifact or reduction of an S/N ratio caused by deterioration of an a-Se characteristic. <P>SOLUTION: In a chest radiography apparatus 1, a solid-state detector 50, a current detection means 30 for detecting a current flowing from an electrostatic recorder 10 of the detector 50, and so on are disposed in a casing 2, forming an image pickup part 4. The current detection means 30 includes a printed circuit board 31, a TAB film 32 for connecting the board 31 and recorder 10, and a charge amplifier IC 33 mounted on the TAB film 32. A distance l spaced between one end of the film 32 and one end of the recorder 10 (reading optical conductive layer 14) is set to 5 mm or more. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image pickup device, and more particularly to an image pickup device provided with a solid-state detector including a layer containing amorphous selenium as a main component.

[0002]

2. Description of the Related Art Conventionally, in medical X-ray photography,
A solid-state detector using a photoconductor such as a selenium plate made of a-Se (amorphous selenium), which is sensitive to radiation such as X-rays, is used in order to reduce the exposure dose to the subject and improve the diagnostic performance. Then, the solid-state detector is irradiated with recording radiation (recording light) such as X-rays carrying the radiation image information to accumulate latent image charges carrying the radiation image information in the power storage unit of the solid-state detector, After that, by scanning the solid-state detector with an electromagnetic wave (reading light) for reading such as a laser beam, the current generated in the solid-state detector is detected via the flat plate electrodes or stripe electrodes on both sides of the solid-state detector, thereby forming a latent image. A system for reading an electrostatic latent image carried by an electric charge, that is, a radiation image information is known (for example, Japanese Patent Laid-Open No. 200-200200).
0-105297, 2000-284056, etc.).

The applicant of the present application has proposed a portable image pickup device in which the above-mentioned solid state detector is built in a compact casing (for example, Japanese Patent Application No. 2000-113946). This device uses a solid-state detector in which a plurality of layers such as a conductive layer and a photoconductive layer are laminated on a glass substrate.
As the glass substrate used here, a glass plate used in a liquid crystal display or the like is mainly used because it is excellent in chemical resistance and heat resistance required for forming a solid-state detector and is inexpensive. To be

[0004]

By the way, in the above-described image pickup device, the solid-state detector and the printed circuit board for detecting the current generated in the solid-state detector generally have a charge amplifier IC mounted thereon. TAB (Tape Automa
ted Bonding) The film is connected. here,
Both ends of the TAB film are pressed by a heating head to be thermocompression bonded to the glass substrate and the printed circuit board of the solid state detector, respectively.

However, a-Se used in the above solid-state detector has low heat resistance and has a glass transition temperature (Tg).
Since it is as low as 42 ° C, when the heating head is brought close to the solid-state detector (a-Se) when the TAB film is thermocompression bonded,
Since the temperature of a-Se exceeds the glass transition temperature and the characteristics of a-Se change, there is a possibility that artifacts may occur or the S / N may decrease in the region where the characteristics change. The same problem occurs when an IC such as a charge amplifier is directly thermocompression-bonded to the glass substrate.

In view of the above circumstances, the present invention is produced by heating and pressure bonding a wiring substrate such as a TAB film in an image pickup device including a solid-state detector including a layer containing a-Se as a main component. It is an object of the present invention to provide an image pickup apparatus in which the occurrence of artifacts due to the deterioration of the characteristics of Se and the reduction of S / N are suppressed.

[0007]

A first image pickup device according to the present invention is provided with an electrostatic recording portion including a layer containing amorphous selenium as a main component on a substrate, and uses image information as an electrostatic latent image. A solid-state detector for recording and generating a current according to an electrostatic latent image by a predetermined process, and a wiring substrate having a wiring for detecting the generated current, the wiring substrate,
It is characterized in that it is thermocompression-bonded to the layer containing amorphous selenium as a main component at a distance of 5 mm or more on the substrate.

In the first image pickup device described above, it is desirable that the distance between the layer containing amorphous selenium as a main component on the substrate and the wiring substrate is 50 mm or less.

A second image pickup device according to the present invention comprises an electrostatic recording portion including a layer containing amorphous selenium as a main component on a substrate, and records image information as an electrostatic latent image,
A solid-state detector that generates a current according to an electrostatic latent image by a predetermined process and an IC that detects the generated current are provided.
However, it is characterized in that it is thermocompression-bonded to the layer containing amorphous selenium as a main component at a distance of 5 mm or more on the substrate.

In the second image pickup device, a layer containing amorphous selenium as a main component and an IC are formed on the substrate.
It is desirable that the separation distance between and is 50 mm or less.

In the above-mentioned first and second image pickup devices, the "solid-state detector" means that the image information is quieted by irradiating light carrying image information (not limited to visible light, but also including radiation). It means something that can be recorded as an electrostatic latent image. For example, by recording image information as an electrostatic latent image and scanning with an electromagnetic wave for reading, a current corresponding to the electrostatic latent image is generated. And the electrostatic recording body described in JP 2000-105297 A and the like.

[0012]

According to the first image pickup device of the present invention, an electrostatic recording portion including a layer containing amorphous selenium (a-Se) as a main component is provided on a substrate, and image information is stored as an electrostatic latent image. As a wiring substrate having a solid-state detector for generating a current according to an electrostatic latent image by a predetermined process and a wiring substrate having a wiring for detecting the generated current. Is heated and pressure-bonded to the substrate of the solid-state detector with a distance of 5 mm or more from the layer containing amorphous selenium as a main component on the substrate of the solid-state detector. At this time, even if the heating head is pressed against the wiring substrate, the temperature of a-Se does not exceed 42 ° C., which is the glass transition temperature of a-Se, due to the heat generated by the heating head. Artifact due to alteration There can be prevented or generated, that the S / N is lowered.

Further, the second image pickup device of the present invention comprises an electrostatic recording portion including a layer containing amorphous selenium (a-Se) as a main component on the substrate, and the image information is an electrostatic latent image. And a solid-state detector that generates a current according to an electrostatic latent image by a predetermined process, and an IC that detects the generated current.
In the image pickup apparatus including the IC, the IC is heated and pressure-bonded to the substrate of the solid-state detector with a distance of 5 mm or more from the layer containing amorphous selenium as a main component on the substrate of the solid-state detector. Even if the heating head is pressed against the IC when it is thermocompression bonded to the substrate of the detector, the temperature of a-Se does not exceed 42 ° C. which is the glass transition temperature of a-Se due to the heat generated by the heating head. Therefore, a-S
Artifacts may occur due to alteration of e, and S / N
Can be prevented from decreasing.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a side sectional view showing a schematic configuration of a chest imaging apparatus 1 which is an embodiment of the present invention. As shown in FIG. 1, this chest imaging apparatus 1
The imaging section 4 is supported on the imaging support column 3 so as to be able to move up and down through an actuator (not shown) such as a ball screw or a cylinder.

The image pickup section 4 is a solid-state detector 50 having an electrostatic recording section 10 as an image pickup device formed on a glass substrate 5.
And a base 6 for holding the glass substrate 5 of the solid-state detector 50
And a reading exposure light source unit 20 used when reading the radiation image information recorded in the electrostatic recording unit 10, and an electrostatic recording unit 10 during scanning exposure of the reading exposure light source unit 20 to the electrostatic recording unit 10. Current detecting means 30 for obtaining an image signal by detecting a current flowing out of the device, a high voltage power supply unit 45 for applying a predetermined voltage to the electrostatic recording unit 10, and an electrostatic recording unit 10 before the start of photographing.
A pre-exposure light source unit 60 for irradiating the subject with pre-exposure light, and a grid arranged on the side facing the subject of the electrostatic recording unit 10 for absorbing scattered rays generated when the radiation transmitted through the subject (not shown) is scattered by the subject. 70, and a control printed circuit board 80 which constitutes a control means for controlling the grid 70, the pre-exposure light source section 60 and the reading exposure light source section 20 are arranged in the housing 2.

Further, the image pickup section 4 passes the image signal from the current detecting means 30 through the inside of the supporting column 3 and the external image processing apparatus 1.
A signal cable 90 for outputting to 50 and a power cable 92 that passes through the inside of the support column 3 and is connected to an external AC (alternating current) power supply 152 are provided.

As described above, by accommodating each element for recording and reading an image in one housing 2, the image pickup section 4 is compactly arranged and can be moved easily, which is practical. is there.

The current detecting means 30 comprises a printed circuit board 31,
A relatively short TAB whose one end is connected to the printed circuit board 31
(Tape Automated Bonding) film 32 and charge amplifier IC mounted on the TAB film 32
It consists of 33. The other end of the TAB film 32 is connected to the electrostatic recording unit 10.

FIG. 2 is a view showing an arrangement relationship between an example of the solid state detector 50 and the reading exposure light source section 20. Note that FIG.
In the figure, the base 6 described later is omitted.

The solid-state detector 50 comprises a glass substrate 5 and an electrostatic recording section 10 formed on the glass substrate 5. The electrostatic recording unit 10 records radiation image information as an electrostatic latent image and generates a current according to the electrostatic latent image by scanning with a reading electromagnetic wave (hereinafter referred to as reading light). Specifically, as shown in FIG. 2, the first conductive layer 11 having a transparency with respect to recording electromagnetic waves such as X-rays that have passed through the subject (hereinafter referred to as recording light), the irradiation of the recording light is performed. The recording photoconductive layer 12 that generates an electric charge by being received and exhibits conductivity, and acts as an approximately insulator against the latent image polar charges (for example, negative charges) charged in the first conductive layer 11, and The charge transport layer 13 that acts as a substantially conductive body against the transport polar charge (positive charge in the previous example) opposite to the latent image polar charge, generates a charge by being irradiated with the reading light, and thereby becomes conductive. A photoconductive layer 14 for reading,
The second conductive layer 15 that is transparent to the reading light is laminated in this order. A power storage unit 19 is formed at the interface between the recording photoconductive layer 12 and the charge transport layer 13.

The first conductive layer 11 and the second conductive layer 15 each form an electrode. The electrode of the first conductive layer 11 is a two-dimensional flat plate electrode, and the electrode of the second conductive layer 15 is As shown by the diagonal lines in the figure, a large number of elements (linear electrodes) 15a are stripe electrodes arranged in a stripe pattern at a pixel pitch (for example, Japanese Patent Laid-Open No. 2000-105).
(See the electrostatic recording body described in Japanese Patent No. 297). Element 1
The arrangement direction of 5a corresponds to the main scanning direction, and the longitudinal direction of the element 15a corresponds to the sub scanning direction.

The reading photoconductive layer 14 has a high sensitivity to electromagnetic waves in the wavelength range from near ultraviolet to blue (300 to 550 nm) and has a wavelength in the red range (700 nm or more).
Having low sensitivity to the electromagnetic waves of, specifically,
A photoconductive substance containing a-Se as a main component is preferable.

In this embodiment, the element 1
5a has a width of 50 μm, is arranged at a pixel pitch of 100 μm, and is made of a material that transmits light having a wavelength of 550 nm or less, such as ITO or thin film Al. Further, a-Se is used for the reading photoconductive layer 14.

FIG. 3 shows the solid-state detector 5 of the image pickup section 4 shown in FIG.
0 is a view more specifically showing a mounting portion of the base 6 to the housing 2, (A) is a front view seen from the electrostatic recording portion 10 side,
(B) and (C) are sectional views taken along the line BB of (A), respectively.
-C line sectional drawing is shown. The base 6 supports the glass substrate 5 of the solid-state detector 50 as shown in the figure. In general, the glass substrate 5 is very thin with a thickness of 1.1 mm or less, whereas the base 6 is made of sufficiently thick glass so as not to bend even if it is arranged vertically as shown in the figure. Then, it is set to 5 mm or more. The base 6 is transparent to the light output from the reading light source and the pre-exposure light source, and has substantially the same refractive index and thermal expansion coefficient as the glass substrate 5. Also,
In order to prevent light loss and stray light due to reflection of the reading light, the reading light incident surface 6a is coated with an AR (antireflection) coating. The base 6 and the substrate 5 are adhered to each other with an adhesive such as epoxy resin or Canadian balsam. As shown in FIG. 3, the base 6 is sandwiched at its four corners, left and right, and the lower end by mounting members 7 made of metal or the like, reinforced and fixed to the housing 2. Between the upper end of the base 6 and the mounting member 7, there is provided a gap 8 through which the TAB film 32 for connecting the electrostatic recording unit 10 and the printed circuit board 31 is inserted. Specifically, as shown in the cross-sectional view (B), a portion of the base 6 located above the electrostatic recording portion 10 and the mounting member 7.
A gap 8 is provided between the mounting member 7 and the base member 6 at the upper right corner as shown in the sectional view (C).
It is sandwiched by.

The reading exposure light source unit 20 includes a light source composed of a plurality of LED chips arranged in a line, and an optical system for linearly irradiating the light output from the light source on the electrostatic recording unit 10. Use one consisting of. It should be noted that the stripe electrode 1 of the electrostatic recording unit 10 is driven by a linear motor (not shown) with the light source unit 20 kept at a necessary distance from the electrostatic recording unit 10.
The entire surface of the electrostatic recording unit 10 is exposed by scanning in the longitudinal direction of 5a.

As described above, the reading photoconductive layer 14 has high sensitivity to electromagnetic waves in the wavelength range from near ultraviolet to blue (300 to 550 nm), and has a wavelength in the red range (70).
Since it has a low sensitivity to electromagnetic waves of 0 nm or more), a light source that emits light having a wavelength in the near-ultraviolet to blue region of 550 nm or less is used.

A specific example of the reading exposure light source section 20 will be shown in FIG. 4 and its configuration and operation will be described. FIG. 4 (A) shows
FIG. 4 is a side view showing a detailed configuration of the reading exposure light source unit 20 shown in FIG. 2 as seen from the Y direction, and FIG. 4B is an XY sectional view of the reading exposure light source unit 20. In FIG. 4, the above-mentioned base 6 is omitted.

As shown in FIG. 4, the exposure light source unit for reading 20 is used.
Is a light source 101 including a plurality of LED chips 101a, 101b, ... arranged linearly in the Z-axis direction, and for improving the quality of light emitted from the light source 101,
A slit 102 having an opening 102a extending in the longitudinal direction of the light source 101 and an opening 102a of the slit 102.
The first optical means 106 including the cylindrical lenses 104 and 105 which are the optical members 103 for converging the light toward the light source, and the light passing through the first optical means 106 as the light source 1
The second optical means 109 is composed of cylindrical lenses 107 and 108 for focusing on the image detector surface in a direction orthogonal to the longitudinal direction of 01.

The slit 102 spatially filters the light output from the light source to suppress flare light and determines the beam diameter on the detector. The slit may be any slit as long as it suppresses the spatial spread of light, and may be not only a mechanical slit having an opening as in the present embodiment but also an optical gap such as a density distribution filter.

Light emitted from each light emitting point of the light source 101, that is, from each LED chip 101a, 101b, ... Is slit 102 by cylindrical lenses 104 and 105.
The light is focused and filtered in the longitudinal direction of the aperture 102a, and is focused in the direction orthogonal to the longitudinal direction of the light source by the cylindrical lenses 107 and 108 of the second optical means 109, and the electrostatic recording portion 10 is irradiated with the light. Each LED
Since the light beam from the chip spreads isotropically and diffuses, and is not focused in the longitudinal direction of the light source, the light from each chip diffuses in the longitudinal direction of the light source on the detector. Thereby, the light from the light source 101 is emitted from the electrostatic recording unit 1.
0 is irradiated linearly, and the light from each chip simultaneously exposes a plurality of pixels arranged in a line. That is,
Each pixel on the electrostatic recording unit 10 is simultaneously exposed by the light output from the plurality of LED chips. For example, although FIG. 4 is a schematic view, the point A on the electrostatic recording unit 10 is simultaneously exposed by seven LED chips.

More specifically, for example, the focal length of the optical system is 40 mm, the pixel size is 100 μm, the LED chip interval (light emitting point interval) is 200 μm, and the beam divergence angle from the LED chip in the longitudinal direction of the light source is 120 °. (Half), each pixel on the detector is simultaneously exposed to light from at least 700 or more LED chips.

In the reading exposure light source section 20 described above, the cylindrical lens 10 of the first optical means 106 is used.
Instead of 4, 105, a Selfoc lens may be used.

The light source 101 of the exposure light source unit for reading 20 described above is formed by arranging a plurality of LED chips, but a plurality of LD chips may be arranged instead of the LED chips. Further, an LED array or an LD array in which a plurality of light emitting points are arranged in a line may be used as a light source.

In the present embodiment, the example in which the light source having a plurality of light emitting points linearly is provided as the exposure light source unit for reading has been described, but the present invention is not limited to this. It is also possible to use the reading exposure light source unit described in Japanese Patent Laid-Open No. 2000-162726, which comprises a planar light source in which minute light sources are arranged in a plane and a light source control means for controlling the planar light source.

FIG. 5 is a perspective view of the exposure light source unit for reading 120 and the electrostatic recording unit 10 (A), an XZ sectional view (B), and XY.
A sectional view (C) is shown. The glass substrate 5 is omitted in FIG. The exposure light source unit for reading 120 includes a planar light source 130 and a light source control unit 140 that controls the light source 130.
The surface light source 130 is integrally formed with the electrostatic recording unit 10 between the second conductive layer 15 of the electrostatic recording unit 10 and the glass substrate 5.

More specifically, the planar light source 130 is an EL light-emitting body and is composed of a conductive layer 131, an EL layer 132, and a conductive layer 133. An insulating layer 134 is provided between the second conductive layer 15 and the conductive layer 131 of the electrostatic recording unit 10. The conductive layer 131 is a stripe electrode in which a large number of elements (linear electrodes) 131a are arranged in a stripe pattern at a pixel pitch so as to intersect (substantially orthogonal in this example) the element 15a of the electrostatic recording unit 10. . As a result, a large number of linear light sources formed by the elements 131a (hatched portions in the drawing) are arranged in a plane. Each element 131
Is connected to the light source control means 140. In addition, each element 131a is formed of a material that is transparent to the EL light from the EL layer 132. The conductive layer 133 is a flat plate electrode and is formed by totally reflecting the EL light emitted from the EL layer 132.

The light source control means 140 includes an element 131.
a and the conductive layer 133 facing it, the elements 131a individually or a plurality of or all the elements 1a.
A predetermined voltage is simultaneously applied to 31a, and a predetermined DC voltage is applied between each element 131a and the conductive layer 133 while sequentially switching the elements 131a. By applying this DC voltage, the element 131a
EL light is emitted from the EL layer 132 sandwiched between the conductive layer 133 and the conductive layer 133. Since the element 131a has a linear shape, the EL light transmitted through the element 131a is used as a linear reading light. That is, the planar light source 130
This is equivalent to a linear array of minute light sources, and the elements 131a are sequentially switched to emit EL light, whereby the electrostatic recording section 10 is electrically scanned with the reading light.

By using the surface light source integrally formed with the electrostatic recording unit 10 as the exposure light source for reading, a space for moving the light source, a linear motor for moving the light source, etc. are not required, and the entire apparatus is provided. It can be made more compact.

Further, the reading exposure light source section 120 comprising the planar light source 130 and the light source control means 140 can also serve as the pre-exposure light source section. Specifically, a predetermined voltage is simultaneously applied between the plurality of elements 131a and the conductive layer 133. At this time, by applying a voltage, the EL layer 132
It suffices that the pre-exposure light emitted from the device irradiates the electrostatic recording portion 10 substantially uniformly, and the number of the elements 131a does not matter. For example, it may be thinned out at a predetermined interval, or all elements 131a may be thinned out.

If the reading light and the light for pre-exposure are emitted by using the same light source as described above, it is not necessary to provide a special light source for pre-exposure, so that the apparatus can be made more compact. Since the number of parts of the device can be reduced, the device can be inexpensive.

When the planar light source 130 integrally formed with the electrostatic recording unit 10 is applied as a reading exposure light source and a pre-exposure light source, the integrated electrostatic recording unit 10 and The planar light source 130 may be supported by the base from the planar light source 130 side. At this time,
The base need not be light transmissive.

FIG. 6 shows the electrostatic recording section 10 and the current detecting means 3.
It is a figure showing the details of the connection mode of 0 and the high voltage power supply part 45. As shown in the figure, each element 15a of the electrostatic recording unit 10 is connected to the charge amplifier IC 33 via a print pattern (not shown) formed on the TAB film 32.
And a charge amplifier IC 33 connected to the print pattern formed on the TAB film 32 (not shown)
It is connected to the printed circuit board 31 via. In the present embodiment, not all the elements 15a are connected to one charge amplifier IC33, but several to several tens of charge amplifier ICs 33 are provided as a whole, and several to several hundred elements 15a that are sequentially adjacent to each other are provided. Each of them is connected to each charge amplifier IC 33.

The connection between the electrostatic recording unit 10 and the current detecting means 30 in this embodiment will be described in more detail with reference to the drawings. FIG. 7A is a top view of the electrostatic recording unit 10 and the current detecting unit 30, and FIG. 7B is a side view of the electrostatic recording unit 10 and the current detecting unit 30.

By pressing the heating head 38 from above the end portion of the TAB film 32, the TAB film 32 and the plurality of elements 15a on the glass substrate 5 are separated from each other by the ACF.
(Anisotropic Conductive Film)
It is thermocompression bonded via 35.

At this time, the heat generated by the heating head 38 may change the quality of the reading photoconductive layer 14 made of a-Se. Therefore, the edge of the reading photoconductive layer 14 and the edge of the TAB film 32 may be changed. By setting the separation distance l of 5 mm or more, the temperature of the reading photoconductive layer 14 due to the heat generated by the heating head 38 is 42 ° C., which is the glass transition temperature of a-Se.
Therefore, it is possible to prevent the occurrence of artifacts and the reduction of S / N due to the alteration of a-Se. Further, the longer the separation distance l, the more the influence of the heat generated by the heating head 38 on the reading photoconductive layer 14 can be suppressed. However, if the separation distance l is made too long, the image area of the electrostatic recording unit 10 becomes large. On the other hand, since the housing 2 becomes large and the commercialability is deteriorated, the separation distance l is 5
It is desirable to set it to 0 mm or less. The heating head 3
By providing a heat shield member 39 between the electrostatic recording unit 10 and the electrostatic recording unit 10, the influence of heat can be suppressed more effectively.

Further, the printed circuit board 31 and the TAB film 32 are also thermocompression bonded via the ACF 34 in the same manner.

The current detecting means 30 is not limited to the above-mentioned mode, but may be a mode in which the charge amplifier IC 33 is not formed on the TAB film 32 as shown in FIG. 8, for example. FIG. 8A shows the electrostatic recording unit 10.
FIG. 8B is a side view of the electrostatic recording unit 10 and the current detecting unit 30. FIG.

In this embodiment, the charge amplifier IC 33 is directly thermocompression-bonded to the plurality of elements 15a on the glass substrate 5 and the wiring 37 from the output terminal of the charge amplifier IC 33 to the TAB film 32.

By pressing the heating head 38 from above the charge amplifier IC 33, the charge amplifier IC 3
3 and the plurality of elements 15a and the wiring 37 on the glass substrate 5 are thermocompression bonded via the ACF 36. Similarly, the wiring 37 on the glass substrate 5 and the TAB film 32, and the printed circuit board 31 and the TAB film 32 are also thermocompression bonded via the ACF.

Even in such an embodiment, the distance l between the end of the photoconductive layer for reading 14 and the end of the charge amplifier IC 33 is 5 mm or more and 50 m or more for the same reason as described above.
It is desirable that it is m or less.

The first conductive layer 11 which is the plane electrode of the electrostatic recording section 10 is provided with a non-image area 11a which is formed to be larger than the image recording area. In this non-image area 11a, the hot side (core wire) of the cable 46 output from the high-voltage power supply section 45 arranged near the electrostatic recording section 10 is provided.
46a is directly bonded, and the ground side (sheath) 46b of the cable 46 is connected to the printed circuit board 31 by screwing 47. In this embodiment, the hot side 46a has a negative potential with respect to the ground side 46b. The ground side 46b connected to the printed circuit board 31 is
Each charge amplifier IC33 through the TAB film 32
Is commonly connected to the charge amplifier IC33.
It also becomes the reference potential of.

As described above, in the apparatus 1 having the above structure, the high-voltage power supply section 45 is arranged in the vicinity of the electrostatic recording section 10 and the printed circuit board 31, so that the cable 46 for connecting the power supply can be shortened, and the special cable is special. Since it is not necessary to use a cable, the cable 46 can be easily routed, and the hot side 46a and the ground side 46b of the cable 46 are connected to the electrostatic recording unit 10 and the printed circuit board 31 by direct bonding or screwing. The cost can be reduced without the need for a special connector.

FIG. 9 shows the details of the current detecting means 30 and the high-voltage power supply section 45 provided in the housing 2, and an image provided outside them and the solid-state detector 50, the current detecting means 30, and the apparatus 1. 3 is a block diagram showing a connection mode with a processing device 150 and the like. FIG.

The high-voltage power supply unit 45 is a circuit in which the high-voltage power supply 40 and the bias switching means 42 are integrated, and the high-voltage power supply 40 once switches the bias application / short-circuiting to the electrostatic recording unit 10. Therefore, it is connected to the electrostatic recording unit 10 via the bias switching unit 45. This circuit is
It is designed to prevent excessive charging / discharging current in order to limit the peak value of the current flowing at the time of switching and prevent the destruction of the portion where the current of the device is concentrated.

The charge amplifier IC 33 provided on the TAB film 32 is provided for each element 1 of the electrostatic recording unit 10.
It is provided with a large number of charge amplifiers 33a and sample-hold (S / H) 33b connected for each 5a, and a multiplexer 33c for multiplexing the signals from each sample-hold 33b. The current flowing out of the electrostatic recording unit 10 is converted into a voltage by each charge amplifier 33a,
The voltage is sampled and held by the sample hold 33b at a predetermined timing, and the voltage corresponding to each sampled and held element 15a is sequentially output from the multiplexer 33c so as to be switched in the arrangement order of the elements 15a (corresponding to a part of main scanning). To). The signals sequentially output from the multiplexer 33c are printed circuit boards 31.
The voltage input to the multiplexer 31c provided above and corresponding to each element 15a is applied to the element 15a.
The main scanning is completed by sequentially outputting from the multiplexer 31c so as to switch in the arrangement order of a. Multiplexer 31
The signals sequentially output from c are converted into digital signals by the A / D converter 31a, and the digital signals are stored in the memory 31b.
Stored in.

As the pre-exposure light source section 60, a light source that emits / quenches light in a short time and has a very small afterglow is required. In this embodiment, an external electrode type rare gas fluorescent lamp is used. More specifically, the pre-exposure light source unit 60, as shown in FIG.
A plurality of external electrode type rare gas fluorescent lamps 61 extending in the depth direction in the drawing, a wavelength selection filter 62 inserted between the fluorescent lamps 61 and the electrostatic recording unit 10, and a fluorescent lamp 61.
And a reflecting plate 63 disposed behind the fluorescent lamp 61 for efficiently reflecting the light output from the fluorescent lamp 61 to the electrostatic recording unit 10 side. It should be noted that the pre-exposure light may be applied to the entire second electrode layer 15 of the electrostatic recording unit 10, and no particular focusing means is required, but the illuminance distribution is preferably small. Instead of the fluorescent lamp, a light source in which LED chips are arranged side by side can be used as the light source. Further, by providing the base 6 with wavelength selectivity, the wavelength selection filter 62
Can be omitted.

When the electrostatic latent image is read from the electrostatic recording unit 10, basically all the latent image charges accumulated can be read out, but in some cases the latent image charges cannot be completely read out. It may be left unread as a residual charge in the electrostatic recording unit 10. Further, when an electrostatic latent image is recorded on the electrostatic recording unit 10, a high voltage is applied to the electrostatic recording unit 10 before the irradiation of recording light. At the time of this application, a dark current is generated, and a charge due to the dark current is generated. (Dark current charge) is also accumulated in the electrostatic recording unit 10. Furthermore, the electrostatic recording unit 1 may be caused by other causes.
It is known that various charges are accumulated at 0 before irradiation with recording light. Unnecessary charges such as these residual charges and dark current charges accumulated before the irradiation of the recording light are added to the charges for carrying the image information accumulated by the irradiation of the recording light, so that the static charges are eventually generated. When the electrostatic latent image is read from the electrographic recording unit 10, the output signal contains a signal component due to unnecessary charges in addition to the signal based on the charges carrying the image information, resulting in an afterimage phenomenon and S / N deterioration. Causes problems such as.

The "pre-exposure" is for erasing unnecessary charges accumulated in the image detector before irradiating the image detector with this recording light, and for solving problems such as an afterimage phenomenon and S / N deterioration. It is a thing.

Next, the operation of the chest imaging apparatus 1 thus constructed will be described.

First, the photographing unit 4 is moved up and down and positioned according to the physique of the subject (patient).

Next, the pre-exposure light is irradiated to the electrostatic recording section 10 to erase the unnecessary charges accumulated in the electrostatic recording section 10.

The pre-exposure process may be performed before the voltage is applied to the electrostatic recording section 10 or after the voltage is applied. Further, it may be a mode in which the pre-exposure lighting is turned on before the voltage application and the light is turned off after the voltage application.

At the time of photographing, first, the bias switching means 42.
Thus, the negative electrode of the power source 40 is connected to the first conductor layer 11 and a DC voltage is applied between the first conductor layer 11 and each element 15a to charge both conductor layers 11, 15. As a result, the first conductive layer 11 and the element 15a in the electrostatic recording unit 10 are
A U-shaped electric field that forms the U-shaped recess in the element 15a is formed between and.

After that, when the photographer presses an irradiation button (not shown) in consideration of the timing, the grid 70 arranged on the side of the subject of the photographing section 4 starts to swing, and the swing speed of this grid 70 is a predetermined speed. Is reached and a sufficient voltage is applied to the electrostatic recording unit 10 by the above voltage application, and X-rays are emitted.

When the electrostatic recording section 10 is irradiated with X-rays transmitted through the object, that is, recording light carrying radiation image information of the object, positive and negative charge pairs are generated in the recording photoconductive layer 12 of the electrostatic recording section 10. The generated negative charges are concentrated on the element 15a along the electric field distribution described above, and the negative charges are accumulated in the electricity storage unit 19 formed at the interface between the recording photoconductive layer 12 and the charge transport layer 13. It Since the amount of the accumulated negative charges, that is, the latent image polar charges, is approximately proportional to the amount of radiation that has passed through the subject, the latent image polar charges carry an electrostatic latent image. In this way, the electrostatic latent image is recorded on the electrostatic recording unit 1.
It is recorded at 0. On the other hand, the positive charges generated in the recording photoconductive layer 12 are attracted to the first conductive layer 11 and are recombined with the negative charges injected from the high voltage power source 40 to disappear.

When the electrostatic latent image is read from the electrostatic recording unit 10 after the X-ray irradiation and the image recording, the electrostatic recording unit 1 is used.
The bias switching means 42 short-circuits the conductive layers 11 and 15 of 0.

The exposure light source unit 20 for reading operates, and the light source 101
The reading light L is output from the device, and the element 15a is moved in the longitudinal direction, that is, the sub-scanning direction by a linear motor (not shown) to scan the entire surface of the electrostatic recording unit 10. As described above with respect to the operation of the exposure light source unit for reading 20, the linear reading light L output from the light source unit 20 passes through the base 6 and the glass substrate 5 and is transmitted to each element 15a of the electrostatic recording unit 10. Is irradiated.

Then, positive and negative charge pairs are generated in the reading photoconductive layer 14, and the positive charges therein are attracted to the negative charges (latent image polarity charges) accumulated in the electricity storage unit 19 so that the charge transport layer is formed. It rapidly moves in 13 and re-combines with latent image polar charges in the electricity storage unit 19 and disappears. On the other hand, the reading photoconductive layer 14
The negative charge generated in the second charge layer is recombined with the positive charge injected into the second conductive layer 15 and disappears. In this way, the electrostatic recording unit 1
The negative charge accumulated at 0 disappears due to charge recombination,
A current is generated in the electrostatic recording unit 10 due to the movement of charges during the charge recombination.

The current detection charge amplifier 33a connected to each element 15a detects this current in parallel (simultaneously) for each element 15a. The signal detected by the charge amplifier 33a is sample-held by the sample-hold 33b, and the voltage corresponding to each sample-held element 15a is sequentially output from the multiplexer 33c so that the voltage is switched in the arrangement order of the elements 15a. The signals are further sequentially output by the multiplexer 31c, A / D converted by the A / D converter 31a, and stored in the memory 31b as a digital image signal.

The electrostatic recording section 10 is accompanied by the scanning exposure of the reading light L.
The electric current flowing therein corresponds to the latent image charge, that is, the electrostatic latent image, and the image signal obtained by detecting this electric current represents the electrostatic latent image, so that the electrostatic latent image can be read.

The image signal once stored in the memory 31b is sent to the external image processing apparatus 150 via the signal cable 90, is subjected to appropriate image processing in the image processing apparatus 150, and is taken together with the photographing information to the network. 15
1 is uploaded and sent to the server or printer.

In the above description, the apparatus for photographing the chest is taken as an example of the embodiment of the present invention, but the present invention is not limited to this, and as shown in FIG. In addition, the present invention can be applied to the X-ray imaging apparatus 2 in which the imaging unit 4 is further supported by the movable unit, which is supported so as to be able to move up and down, rotate, and tilt in an oblique direction.

The photographing section 4 supported by the U-arm 200 and the irradiation section 210 are arranged at the facing positions, and the U-arm is moved up and down and rotated according to the photographing region and photographing angle of the subject to adjust the position. Take a picture. The image capturing unit 4 is the same as that in the above-described embodiment, and the image capturing method is also the same, so detailed description thereof will be omitted.

The radiation image pickup apparatus according to the present invention is U
It can be used as an imaging unit of an X-ray imaging apparatus equipped with a C-arm in the same manner as an imaging apparatus equipped with an -arm.

[Brief description of drawings]

FIG. 1 is a side sectional view showing a schematic configuration of a chest imaging apparatus according to an embodiment of the present invention.

FIG. 2 is a perspective view of an image detector used in the chest imaging apparatus and a diagram showing a positional relationship between an exposure light source unit for reading.

FIG. 3 is a diagram showing a base supporting the image detector.

FIG. 4 is a diagram showing a detailed configuration of a reading exposure light source unit.

FIG. 5 is a diagram showing another mode of the exposure light source unit for reading.

FIG. 6 is a diagram showing details of a connection mode of an image detector, a current detection unit, and a high-voltage power supply unit.

FIG. 7 is a diagram showing details of a connection mode of an image detector and a current detection means.

FIG. 8 is a diagram showing details of a connection mode of an image detector and a current detection means.

FIG. 9 is a block diagram showing details of a current detection unit and a high-voltage power supply unit and a connection mode between these units and an image detector.

FIG. 10 is a diagram showing a mode in which the image pickup apparatus of the present invention is applied to an X-ray imaging apparatus having a U-arm.

[Explanation of symbols]

1 chest imaging device 3 Supporting columns for shooting 4 Shooting department 10 image detector 20 Exposure light source for reading 30 Current detection means 40 high voltage power supply 45 High voltage power supply 60 Pre-exposure light source section 70 grid 80 control printed circuit board 90 signal cable 92 power cable

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H04N 5/335 H04N 1/04 EF term (reference) 2G088 EE01 FF02 GG21 JJ09 JJ32 4M118 AA05 AB01 BA05 BA19 CA15 CB05 DD01 DD02 GA01 GA09 GA10 GD05 GD07 HA21 HA26 HA29 5C024 AX12 AX17 DX04 JX02 5C072 AA01 BA11 BA17 EA08 FA05 VA01

Claims (4)

[Claims] 1. An electrostatic recording section including a layer containing amorphous selenium as a main component is provided on a substrate, image information is recorded as an electrostatic latent image, and the electrostatic latent image is processed by a predetermined process. A solid-state detector for generating an electric current, and a wiring substrate having a wiring for detecting the generated electric current, wherein the wiring substrate and the layer containing amorphous selenium as a main component on the substrate are 5 mm or more. An image pickup device, wherein the image pickup device is separated from the substrate and is thermocompression bonded to the substrate. 2. The image pickup device according to claim 1, wherein a separation distance between the layer containing amorphous selenium as a main component on the substrate and the wiring substrate is 50 mm or less. 3. An electrostatic recording section including a layer containing amorphous selenium as a main component is provided on a substrate, image information is recorded as an electrostatic latent image, and the electrostatic latent image is recorded according to a predetermined process. A solid-state detector for generating a current and an IC for detecting the generated current are provided, and the IC is thermocompression-bonded to the substrate at a distance of 5 mm or more from the layer containing amorphous selenium as a main component on the substrate. An image pickup device characterized in that. 4. The separation distance between the layer containing the amorphous selenium as a main component and the IC is 50 m on the substrate.
The image pickup device according to claim 3, wherein the image pickup device has a thickness of m or less.