JPH01114780A - X-ray detecting device - Google Patents

Abstract

PURPOSE:To thin and lighten a device, to decrease the attenuation of X-rays and to realize a long service life of the device by covering a photoelectric converting part and an X-ray visible light converting part provided on a substrate, with a light transmissive and moisture- proof adhesive layer, and also, covering the upper face with an Al foil inserted fluororesin. CONSTITUTION:On the upper surface of a substrate 1 whose X-ray absorbing power is weak, and also, which consists of a carbon fiber/epoxy composite material being light in weight and tough, an Al thin film 2 for reflecting a visible light and shielding an electric noise is provided. In the center of the thin film 2, a foundation electrode 4 which has used a polyimide film 3 whose X-ray absorbing power is weak, as a base material, and has brought Al/Cr to vacuum vapor-deposition on the upper surface is formed, and a photoelectric converting element 5 consisting of amorphous silicon, and a transparent electrode film 6 are formed on the upper surface of the electrode 4, and on its upper surface, respectively, by which a photoelectric converting part 20 is constituted. The converting part 20 is covered with a light transmissive and moisture-proof adhesive layer 7a, and also, on its surface, an X-ray visible light converting part 8 is laminated. On the upper surface of the converting part 8, a light transmissive and moisture-proof adhesive film 7b is laminated, and also, a Tedra film 9 (Al foil inserted fluororesin) is stuck. In such a way, deterioration of the function caused by moisture absorption of the converting part is prevented, and the service life can be extended.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to an X-ray detection device.

[Prior Art] FIG. 2 is a longitudinal sectional view of a conventional X-ray detection device. 10
A is a substrate made of acrylic material and has a thickness of 3 to 4 cm, and an AQ thin film 11a having the same planar shape as the substrate 10a is provided on the substrate 10a. The Af2 thin@11a substrate 10a
A photoelectric conversion section 30 using a base material 12 made of polyimide film and having the same planar shape as the substrate 10a is provided on the entire upper surface in the opposite direction. Substrate 10a of the base material 12
A base electrode 13 made of AQ, Ag, Cr, etc. is formed on the upper surface in the opposite direction.
A photoelectric conversion element 14 of a p-i-n type amorphous semiconductor diode is formed on the upper surface in the direction opposite to Oa, and S
A transparent electrode film 15 made of not + ITO or the like is formed. The components 12, 13, 14, and 15 formed on the AQ thin film 11a collectively form a photoelectric conversion section 30. Furthermore, the entire upper surface of the photoelectric conversion unit 30 in the direction opposite to the substrate 10a has the same planar shape as the substrate lOa (
1. An X-ray visible light converting means t6 coated with a phosphor made of ZnS or the like that converts X-rays into visible light is adhered to the entire upper surface of the X-ray visible light converting means 16 in the direction opposite to the substrate 10a. An AQ thin film 11b having the same planar shape as the substrate 10a is provided, and finally all the above-mentioned components 10a, lIa, 12,
13. A substrate 10b made of the same acrylic material as the substrate 10a is bonded to the entire upper surface of the A12 thin film 11b so as to sandwich +4.15 and 16.1 lb.

When X-rays are incident on the X-ray detection device configured as described above, the X-rays pass through various elements constituting the X-ray detection device and are directly or indirectly transmitted to the X-ray visible light conversion means 16.
incident on . This converts the X-rays into visible light, which passes through the transparent electrode film 15 and directly passes through the photoelectric conversion element 1.
4, or reflected by the AQ thin films 11a and llb provided at positions sandwiching the photoelectric conversion element 14, and incident on the photoelectric conversion element 14. This creates a potential difference between the base electrode 13 and the transparent electrode film 15 that sandwich the photoelectric conversion element 14 . By measuring the potential difference, xmm irradiated to the present X-ray detection device is measured.

[Problems to be Solved by the Invention] However, in the above-mentioned conventional X-ray detection device, in order to maintain strength against external forces applied to the X-ray detection device, the
Since the substrates 10a and jobs made of acrylic material having the same thickness as the gate are provided on both sides of the photoelectric conversion unit 30, the thickness of the entire X-ray detection device becomes thick, and therefore the weight of the device becomes heavy. Also, the substrate 10a or 10b
Since the substrates 10a and 10a are thick, the irradiated X-rays reach the substrates 10a and
There was a problem that the attenuation rate when passing through the IOb was high, making it impossible to accurately detect the X-ray irradiation dose.

Furthermore, the polyimide film that is the material of the base material 12, which is a component of the photoelectric conversion unit 30, is highly hygroscopic, and in the conventional X-ray detection device, the four sides of the base material 12 that are not in contact with other components are directly Since the base material 12 is in contact with the outside air, there is a risk that the base material 12 may absorb moisture from the air and peel off, resulting in a problem that the life of the X-ray detection device is shortened.

The purpose of the present invention is to solve the above problems, to make an X-ray detection device thin and light by using a thin and strong substrate, and to reduce the attenuation of X-rays in the substrate of the X-ray detection device. Moreover, it is an object of the present invention to provide an X-ray detection device that has a longer life span by sealing a polyimide film, which is a base material of a photoelectric conversion section, from the outside air.

[Means for Solving the Problems] The present invention provides at least an amorphous semiconductor photoelectric conversion means using a polyimide film as a base material, an X-ray visible light conversion means, a fluororesin sandwiched between aluminum foil, and one or more transparent layers. It is characterized by being covered with a light moisture-proof adhesive layer.

[Function] With the above configuration, when X-rays enter the X-ray visible light conversion section, they are converted into visible light by the X-ray visible light conversion section and then enter the photoelectric conversion section. At this time, the photoelectric conversion section converts the visible light into an electrical signal and outputs it.

Therefore, the incident X-rays can be detected as electrical signals. Note that by using a material that can maintain strength even if it is thin for the substrate material, the attenuation of incident X-rays in a thick substrate as in the conventional example is reduced, and the X-ray detection device can be made thinner. In addition, by sealing the photoelectric conversion section with a light-transmitting moisture-proof adhesive layer and shielding it from the outside air, the performance of the X-ray detection device will not deteriorate even if the base material of the photoelectric conversion section is made of a highly hygroscopic material. , the life of the X-ray detection device can be extended.

[Example] An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a longitudinal sectional view of the X-ray detection device of the present invention.

l is made of carbon fiber/epoxy composite material, which is a lightweight and strong material with weak X-ray absorption ability, and has a thickness of 0 and 4 rtry,
It is a square substrate of 3501R square, and the upper surface of the substrate 1 has the same planar shape as the substrate 1 and has a thickness of 17 μm, in order to reflect visible light generated in the X-ray visible light converter 8, which will be described later. An AQ thin film 2 is provided to shield electrical noise from the outside. Approximately at the center of the AQ thin film 2, there is a 125 cm
A polyimide film 3 having a weak X-ray absorbing power and having a thickness of 125 μm at the corner is used as a base material, and the entire upper surface of the polyimide film 3 opposite to the AQ thin film 2 is coated with a thickness of 100 μm made of AQ/Cr.
0 base electrodes 4 are vacuum-deposited uniformly in the same planar shape as the polyimide film 3. A thickness t made of amorphous silicon over the entire upper surface of the base electrode 4 in the direction opposite to the substrate l.
oooo The photoelectric conversion element 5 of a human p-1-n type semiconductor diode is uniformly formed by, for example, a glow discharge method,
■TO on the upper surface of the photoelectric conversion element 5 in the direction opposite to the substrate l.
The transparent electrode film 6 is uniformly formed in the same planar shape as the base electrode 4. The components 3, 4, 5, and 6 collectively constitute the photoelectric conversion section 20, and are adhered to approximately the center of the AQ thin@2 with an adhesive. The photoelectric conversion section 20 provided on the surface of the AQ thin film 2 is covered with a transparent moisture-proof adhesive layer 7a. The thickness of the light-transmitting moisture-proof adhesive layer 7a is, for example, at most 0.2 mm.
Made of EVA (ethylene vinyl acetate) in mm. As a result, the photoelectric conversion section 20 is completely sealed from the outside air by the light-transmitting moisture-proof adhesive layer 7a. Furthermore, an X-ray visible light converter 8 for converting X-rays into visible light is laminated on the entire upper surface of the transparent moisture-proof adhesive layer 7a in the direction opposite to the substrate 1 in the same planar shape as the substrate 1. Ru. The X-ray visible light conversion section 8 is formed by coating paper or a synthetic resin film with a phosphor made of Gd, O, S:Tb. Furthermore, a light-transmitting moisture-proof adhesive layer 7bh similar to the light-transmitting moisture-proof adhesive layer 7a is provided on the entire upper surface of the X-ray visible light conversion unit 8 in the direction opposite to the substrate I.
4 The transparent moisture-proof adhesive layer 7b is uniformly laminated on the upper surface of the X-ray image visual light conversion unit 8 so that the upper surface after lamination is parallel to the substrate 1 in the same planar shape as the substrate 1. A Tedra film 9 (AQ foil sandwiched fluororesin film) is adhered to the entire upper surface in the opposite direction to the substrate 1 with an adhesive or the like in the same planar shape as the substrate 1.

In the X-ray detection device configured as described above, for example, when X-rays are incident from the surface of the substrate 1 on which the AQ thin film 2 is not formed, the X-rays are transmitted to the substrate 1. It is hardly absorbed by the components of the X-ray detection device such as the AQ thin film 2, the photoelectric conversion section 20, and the transparent moisture-proof adhesive layer 7a, and enters the X-ray visible light conversion section 8 where it is converted into visible light. . The converted visible light passes through the light-transmitting moisture-proof adhesive layer 7a and enters the photoelectric conversion element 5, which is a component of the photoelectric conversion unit 20. Note that if the visible light obtained by converting the X-rays in the X-ray visible light converter 8 is emitted in the opposite direction to the direction in which the photoelectric converter 20 is located, or if the visible light is emitted in the direction in which the photoelectric converter 20 is located. However, if the visible light does not pass through the photoelectric conversion element 5, the visible light is reflected by the AC foil and the AQ thin film 2 within the TEDRA film 9 and can enter the photoelectric conversion element 5. In this way, the present X-ray detection device is configured so that the conversion efficiency of X-rays into visible light is improved. When visible light is incident on the photoelectric conversion element 5, a potential difference is generated between the transparent electrode film 6 that sandwiches the photoelectric conversion element 5 and the base electrode 4. By measuring this potential difference, the amount of X-ray irradiation to the irradiated object can be measured.

In this embodiment, the material of the base electrode 4 is AQ/C.
r, but A(!, Ag, Cr, A(!/Ag, Cr
/Ag etc. may be used. Translucent moisture-proof adhesive layer 7a.

The material of 7b is EVA (ethylene vinyl acetate)
However, PVB (polyvinyl butyral) may also be used.

The material of the X-ray-light converter 8 is Ga2O, S:Tb, but may also be CaWO, BaPC12:Eu. Furthermore, sandwiching a light-transmitting moisture-proof adhesive layer between the substrate 1 and the AQ thin film 2 or between the AQ thin film 2 and the polyimide film base material 3 is effective in further increasing the moisture-proofing effect.

[Effects of the Invention] As detailed above, according to the present invention, by using a carbon fiber board with low X-ray attenuation and high strength even though it is thin for the substrate of the X-ray detection device, the same strength as the conventional one can be achieved. It is possible to reduce the overall thickness of the X-ray detection device and reduce the weight of the X-ray detection device. In addition, by sealing the photoelectric conversion section, which outputs electrical signals using visible light converted from X-rays, with a transparent, moisture-proof adhesive layer to prevent it from coming into contact with the outside air, we can prevent functional deterioration due to moisture absorption in the photoelectric conversion section. This can be prevented and the life of the X-ray detection device can be extended. or,
Sealing the photoelectric conversion section with the AQ thin film can protect the electrical signal output from the photoelectric conversion section from electrical noise acting from outside the X-ray detection device, and also contributes to preventing false detection of the X-ray dose.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view of an X-ray detection device that is an embodiment of the present invention, and FIG. 2 is a vertical cross-sectional view that is an embodiment of a conventional X-ray detection device. l...Substrate, 3...Base material, 4...Base electrode, 5
...Photoelectric conversion element, 6...Transparent electrode film, 7...
Translucent moisture-proof adhesive layer, 8... X-ray visible light conversion section,
20...Photoelectric conversion section. Patent applicant Kanebuchi Kagaku Kogyo Co., Ltd. Agent: Patent attorney Maeda Ao and one other person Figure 1 Figure 2

Claims (2)

[Claims] (1) Consisting of at least an amorphous semiconductor photoelectric conversion means based on a polyimide film, an X-ray visible light conversion means, a fluororesin film sandwiched with aluminum foil, and one or more light-transmitting and moisture-proof adhesive layers. An X-ray detection device characterized by: (2) The light-transmitting moisture-proof adhesive layer is made of PVB (polyvinyl butyral) or EVA (ethylene vinyl acetate)
X according to claim 1, characterized in that
Line detection device.