JP2008243634A - Gas radiation detector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a gas radiation detector employing a reading substrate using a technique used in electronic industry. <P>SOLUTION: The gas radiation detector is used for detecting primary electrons generated by ionizing radiation in a gas at a reading electrode. The gas radiation detector includes: a drift electrode 10 imparting an electric field accelerating the generated electrons; and a gas electron amplification part 20 locally increased in electric field intensity for generating an electronic avalanche in the gas from one of the primary electrons; wherein the reading electrode includes multiple electrode elements ST1j capable of uniformly detecting the occurrence of an electronic avalanche, an insulator insulating the respective electrode elements, and a static elimination means 80 alleviating charge accumulated in the insulator. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a gas radiation detector. More specifically, the present invention relates to a readout electrode suitable for a gas radiation detector.

  Elementary particles are even smaller than molecules and atoms, and they cannot be seen with the eyes or with an electron microscope. Therefore, detectors for capturing elementary particles are important for the study of elementary particles and nuclei.

  Furthermore, research on material structures using X-rays, γ-rays and neutrons, observation of the universe using balloons, and the forefront of medical practice such as positron emission tomography (hereinafter referred to as “PET”), or Elementary particle detection technology is extremely important when performing non-destructive inspections of products in factories.

  As a prior art, a gas radiation detector (hereinafter referred to as “GEM”) invented by Sauri Fabio of the CERN Research Institute in Europe in 1997 has attracted attention (for example, Patent Document 1). reference).

  8 and 9 are schematic views of the structure of the GEM chamber proposed by Sauri, and FIG. 10 is a diagram for explaining an example and principle of the double-sided flexible substrate of the gas electron amplification unit.

  As shown in FIGS. 8 and 9, the GEM chamber includes a drift electrode 10, a gas electron amplification unit 20, and a readout substrate 30. These are housed in a container (not shown) that can be sealed, and the inside is filled with a gas that matches the radiation to be detected.

  When primary electrons are generated by incident ionizing radiation in the container, the primary electrons are attracted to the gas electron amplification unit 20 by the electric field generated by the drift electrode 10. As shown in FIG. 10, the gas electron amplification unit 20 is a double-sided flexible substrate, and a copper foil of 5 μm is stretched on both surfaces of an insulator such as Kapton having a thickness of 50 μm. Holes with a diameter of 70 μm are formed in the double-sided flexible substrate at a pitch of 140 μm. When a voltage of about 450 V, for example, is applied between the copper foils on both sides, a strong electric field is locally generated at the hole as shown on the left side of FIG.

The primary electrons generated and attracted to the gas electron amplifying unit 20 are accelerated by a strong electric field in the hole and collide with the filled gas to generate an electron avalanche. When the electron avalanche occurs, the number of electrons increases, and the reading substrate 30 detects the position where the electron avalanche has occurred (see Patent Document 1 for more details).
Japanese Patent Publication No. 2001-508935

  FIG. 11 shows the structure of the readout substrate 30 according to the prior art, and FIG. As shown in FIG. 11, in order to read out two-dimensionally, it is necessary to arrange equally strip-shaped conductors at right angles with high accuracy in order to provide uniform detection performance. In one example, a large number of strip-shaped copper foils having a width of 80 μm and a thickness of 4 μm are arranged in parallel, and insulated by an insulator having a thickness of 50 μm such as polyimide. A glass epoxy substrate in which a large number of strip-shaped copper foils having a width of 340 μm and a thickness of 4 μm were embedded in parallel was placed thereunder.

In the manufacturing method, as shown in FIG. 12, the copper pattern is transferred to a glass epoxy substrate. On the other hand, a copper pattern is formed on the polyimide substrate. Adhere both sides with polyimide adhesive. The upper polyimide layer is removed by etching using the copper pattern as a mask. For etching, wet or laser etching is used, but etching is often performed too much, and if any part becomes defective, the entire substrate must be discarded. Further, the shape of the mountain as shown in the lower left of FIG.

  As described above, in the prior art, the readout substrate 30 needs to be specially processed that is not often used for general industrial purposes. For this reason, many man-hours were required to manufacture, and it was expensive. Further, as described above, the application has spread to PET and the like, but it has been a problem in terms of cost. There is also a problem that it is very difficult to produce a fine readout pattern necessary for application to an X-ray detector such as an X-ray.

  An object of the present invention is to solve the above-mentioned problems and to provide a gas radiation detector that employs a readout substrate using a technique used in the electronic industry.

  The inventor can detect the position of the readout substrate not only when the electrons generated by the electron avalanche arrive at the readout electrode, but also by electromagnetic induction caused by movement of the electrons. It has been found that the accumulated charge is adversely affected, and the present invention has been completed.

  (1) A gas radiation detector for detecting a primary electron generated by ionizing radiation in a gas at a readout electrode, a drift electrode for generating an electric field for accelerating the generated electron, and one of the primary electrons A gas electron amplifying unit whose electric field strength is locally increased in order to cause an electron avalanche in the gas, a plurality of electrode elements capable of uniformly detecting the occurrence of an electron avalanche, A gas radiation detector comprising: an insulator that insulates the electrode element; and a charge eliminating unit that relaxes charges accumulated in the insulator.

  The gas radiation detector according to the invention of (1) has a drift electrode for generating an electric field for accelerating the generated electrons and an electric field intensity locally for generating an electron avalanche in gas from one of the primary electrons. The enhanced gas electron amplifying unit, the readout electrode, a large number of electrode elements that can uniformly detect the occurrence of electron avalanche, the insulator that insulates each electrode element, and the charge accumulated in the insulator is relaxed Neutralizing means.

  It is the same as that of the prior art in that it is amplified by causing an electron avalanche in the gas from one of the primary electrons by the gas electron amplifier. The gas radiation detector of the present invention can reduce the accumulation of a large number of charges generated by an electron avalanche by providing the readout electrode with a charge eliminating means for relaxing the charges accumulated in the insulator. In particular, when a large number of charges are accumulated locally, it becomes difficult to detect the readout uniformly. This problem can be solved by providing the static eliminating means.

  It is desirable that the static elimination means add a high resistance body to the gas electron amplifier side of the insulator. It is desirable to apply a carbon paint to add a high resistance body. In addition, you may use the substance which has equivalent insulation performance and resistance value instead of a carbon coating material. For example, a paint of copper oxide or chromium oxide may be used. Furthermore, a film having an equivalent thickness may be fixed instead of being applied.

  Although depending on the specific structure and design specifications of the gas radiation detector, the surface resistance value when a high resistance is added to the insulator is preferably empirically 100 KΩ / □ to 10 MΩ / □. If the surface resistance value is smaller than this, the signal spreads and hinders detection. On the other hand, if the surface resistance value is too high, it takes time to relieve the accumulated electric charge and it is not practical.

  (2) A two-dimensional gas radiation detector for detecting primary electrons generated by ionizing radiation in a gas with a two-dimensional readout electrode, the drift electrode generating an electric field for accelerating the generated electrons, and the primary A gas electron amplifying unit whose electric field strength is locally increased in order to generate an electron avalanche in the gas from one of the electrons, and the two-dimensional readout electrode are opposed to the gas electron amplifying unit, A plurality of parallel electrode elements that extend along a predetermined direction and can uniformly detect the occurrence of an avalanche, an insulator that insulates each electrode element, and a charge accumulated in the insulator is relaxed A first readout electrode having a charge eliminating means; and located in the gas electron amplifying part opposite to the first readout electrode and extending along the second predetermined direction across the first predetermined direction That an electronic avalanche has occurred 2-dimensional gas radiation detector comprising a plurality of parallel electrode elements, and the insulating material for insulating the respective electrode elements, and a second readout electrode with a that can be detected.

  The invention (2) relates to a two-dimensional gas radiation detector. In principle, the invention of (1) can be detected in two dimensions. In terms of configuration, a drift electrode that generates an electric field that accelerates the generated electrons, a gas electron amplifying unit whose electric field strength is locally increased in order to generate an electron avalanche in the gas from one of the primary electrons, The point provided with is the same as the invention of (1).

The readout electrode is configured to be detected in two dimensions. That is, the two-dimensional readout electrode extends along the first predetermined direction so as to face the gas electron amplification unit, and a plurality of parallel electrode elements capable of uniformly detecting the occurrence of an electron avalanche, and each electrode A first readout electrode having an insulator that insulates the device and a charge eliminating means that relaxes the charge accumulated in the insulator; and a first predetermined direction located in the antigas electron amplification section of the first readout electrode And a plurality of parallel electrode elements capable of uniformly detecting the occurrence of an avalanche extending along the second predetermined direction, and an insulator for insulating each electrode element.

  In the invention of (2), the plurality of parallel electrode elements of the second electrode extend across the direction in which the plurality of parallel electrode elements of the first electrode extends. Accordingly, electrode elements parallel to the mesh shape are arranged. Therefore, it is possible to specify the position where the electronic avalanche occurs in two dimensions by measuring the amount of electricity detected in each electrode element. Although it is desirable that the angle crossing the predetermined direction is a right angle, the specific position can be detected by correcting when measuring the quantity of electricity even when crossing at a different angle.

  In addition, the first readout electrode is provided with a static elimination means for relaxing the charge accumulated in the insulator. It should be noted that the charge eliminating means can be provided on both the first readout electrode and the second readout electrode.

  (3) Electrons extending across the first read electrode and the second read electrode along a third direction which is intermediate between the first predetermined direction and the second predetermined direction. The two-dimensional gas according to the invention of (2), further comprising a third readout electrode having a plurality of parallel electrode elements capable of uniformly detecting that an avalanche has occurred and an insulator for insulating each electrode element. Radiation detector.

  The invention of (3) relates to a two-dimensional gas radiation detector as in the invention of (2). In principle, in the case of the special case in the invention of (2), there are cases where the position cannot be specified in two dimensions, and this can be detected.

  That is, in the mesh shape, it is not possible to specify when an electronic avalanche of the same size occurs at two positions simultaneously, but along the third direction, the first readout electrode and the second readout electrode By further including a third readout electrode extending across the region, the position where the electronic avalanche has occurred can be specified.

  The readout substrate or readout electrode used in the inventions (1) to (3) is preferably a flexible substrate that can be manufactured by ordinary electronic substrate technology. By using a flexible substrate, a gas radiation detector having a curved shape corresponding to the application can be manufactured. Also, the reading accuracy can be increased. Furthermore, since it does not depend on a special manufacturing method as in the prior art, it is possible to manufacture a large-sized product at low cost.

  Further, it is desirable that the readout substrate or the electrode element of the readout electrode used in the inventions (1) to (3) is a conductive strip (Stripping). This is because “uniformly detecting” required for these electrode elements can be easily realized by a technology established in the market in the case of a conductive strip.

  Furthermore, the insulator used in the inventions (1) to (3) is preferably made of a polyimide resin. However, other insulators can be used depending on the purpose. For example, it may be a glass epoxy resin or another insulator.

  In the above inventions (1) to (3), the purpose of insulation is to insulate the electrode elements. As a specific configuration, in the invention of (2), by forming conductive band plate patterns on the front and back surfaces of the insulating substrate, a plurality of parallel parallel detections can be made to uniformly detect the occurrence of an electronic avalanche on the front surface. It is also possible to form a plurality of parallel second electrode elements that can uniformly detect the occurrence of an electronic avalanche on the back surface of the first electrode element.

However, depending on the purpose, the conductive band plate may be configured to be covered with an insulator. According to the third electrode element of the invention of (3), a sheet-like element in which a conductive band plate is covered with an insulator can be provided on the antigas electronic amplification part side of the second readout electrode.

  Further, the static eliminating means of the invention of (2) or (3) is a means that employs an insulator of the first readout electrode having an insulation resistance capable of gradually discharging the charge accumulated within a predetermined time. Also good. Depending on the purpose of the gas radiation detector, it is desirable that the cost is low if there is a certain performance. For this purpose, this structure with a small number of manufacturing steps is suitable.

  ADVANTAGE OF THE INVENTION According to this invention, the gas radiation detector which employ | adopted the readout electrode using the technique currently used in the electronic industry can be provided, without performing the special process which is not used so much for general industrial use. In addition, although the application is expanding to PET and the like, it is possible to provide a gas radiation detector that is curved with a size suitable for this. In addition, it is possible to provide a gas radiation detector that employs a readout electrode having a fine readout pattern necessary for an X-ray detector such as an X-ray.

  Embodiments of the present invention will be described below with reference to the drawings. This is merely an example, and the technical scope of the present invention is not limited to this.

<Example 1>
FIG. 1 is a diagram showing a schematic configuration of a gas radiation detector according to the present invention. FIG. 2 shows a specific embodiment realized by the flexible substrate of the two-dimensional readout electrode according to the present invention. FIG. 3 is a conceptual explanatory diagram of an embodiment of the readout electrode according to the present invention.

As shown in FIG. 1, a gas radiation detector 1 of the present invention includes a drift electrode 10 that generates an electric field that accelerates primary electrons generated by ionizing radiation in a gas, and one of the primary electrons in the gas. In order to generate an electron avalanche, a gas electron amplification unit 20 whose electric field intensity is locally increased and a readout electrode 50 are provided. In FIG. 1, the gas electron amplifying unit 20 has one stage, but can have a plurality of stages according to the purpose. Usually three stages are often applied.
Here, the drift electrode 10 and the gas electron amplification unit 20 are the same as those shown in FIG.

In FIG. 1, the readout electrode 50 shows an example of a two-dimensional readout electrode. A plurality of electrode elements ST1j, which are first readout electrodes that can uniformly detect the occurrence of an electron avalanche by the gas electron amplification unit 20, and And an insulator 51 that insulates each electrode element ST1j, and a charge eliminating means 80 using a film coated with a carbon paint that relieves charges accumulated in the insulator 51.

  A large number of electrode elements ST1j as the first readout electrodes are made of a conductive band plate, and each is connected to an electronic circuit A1j for processing a signal detected by the electrode element ST1j. In addition, a large number of electrode elements ST2k as second read electrodes and an insulator 61 that insulates each electrode element ST2k are provided below the first read electrodes. A number of electrode elements ST2k, which are the second readout electrodes, are made of a conductive band plate, and an electronic circuit A2k for processing a signal detected by the electrode element ST2k is connected to each. The first electrode element ST1j and the second electrode element ST2k cross each other at right angles, and the gas electron amplifying unit 20 can uniformly detect two-dimensionally that an electron avalanche has occurred. As will be described later, the insulator 51 and the insulator 61 can be manufactured as a single piece.

A specific embodiment in which the two-dimensional readout electrode according to the present invention is realized by a flexible substrate will be described with reference to FIG. In FIG. 2, the two-dimensional readout electrode 50 extends as a first readout electrode along a first predetermined direction, and a plurality of two-dimensional readout electrodes 50 that can uniformly detect the occurrence of an electron avalanche by the gas electron amplification unit 20. It is manufactured by a flexible substrate 52 in which parallel electrode elements ST1j and an insulator that insulates each electrode element ST1j are integrally manufactured. On the gas electron amplification unit 20 side of the flexible substrate 52, there is provided a static elimination means 80 using a film coated with a carbon paint that relieves charges accumulated in the flexible substrate 52.

  The second readout electrode is provided with a plurality of parallel electrode elements ST2k extending across the first readout electrode at right angles as shown in the figure on the back side of the flexible substrate 52 (opposite side of the first readout electrode). Yes.

  As shown in FIG. 2, the first readout electrode is connected from the connector 53 to the connector 56 via the lead-out portion of the flexible substrate, and further from the connector 71 provided on the metal frame 70 to the connector 74. And is connected to the electronic circuit A1j. Similarly, the second readout electrode is connected from the connector 63 to the connector 66 through the lead-out portion of the flexible board, and further connected from the connector 75 provided on the metal frame 70 to the readout electronic circuit A2k through the connector 78. Has been.

  A conceptual description of an embodiment of the read electrode according to the present invention will be described below with reference to FIG. In FIG. 3, the number of first electrode elements ST1j and second electrode elements ST2k is greatly reduced for convenience of explanation. As shown in FIG. 3, on the surface of the flexible substrate 52 having a thickness of 50 μm, first electrode elements ST1j which are conductive strips of copper foil having a width of 80 μm and a thickness of 5 μm are arranged in parallel at a pitch of 400 μm. On the surface thereof, there is provided a static eliminating means 80 by a film coated with a carbon paint that relaxes charges accumulated in the flexible substrate 52.

  On the back surface of the flexible substrate 52, second electrode elements ST2k, which are conductive strips of copper foil having a width of 340 μm and a thickness of 5 μm, are arranged in parallel at a pitch of 400 μm. The first electrode element ST1j and the second electrode element ST2k are arranged in a mesh pattern so as to cross at a right angle. Further, a substrate 58 is provided on the lower side of the flexible substrate 52 to support insulation and support of the second electrode element ST2k. As shown in FIG. 3, the first electrode element ST1j is connected to the readout electronic circuit A1j, and the second electrode element ST2k is connected to the readout electronic circuit A2k.

  The test results of the two-dimensional gas radiation detector having the above configuration will be described below with reference to the drawings. FIG. 4 is a diagram illustrating an output signal of a two-dimensional readout electrode by a double-sided flexible substrate to which the charge eliminating unit is not applied, and FIG. 5 is a diagram illustrating an output signal of the two-dimensional readout electrode according to the present invention. FIG. 6 is a diagram showing an image detected by the gas radiation detector according to the present invention.

In the test, an electric field between the drift electrode 10 and the gas electron amplification unit (GEM) 20 is set to 1 kV / cm in a mixed gas of 70% argon (Ar) and 30% carbon dioxide (CO ₂ ). A voltage of 450 V was applied to the electron amplifier (GEM) 20, and the electric field between the gas electron amplifier 20 and the readout electrode 50 was set to 6 kV / cm.

  The inventor first tried to simply perform two-dimensional readout using a double-sided flexible substrate, and the result was as shown in FIG. FIG. 4 shows output signals of the first readout electrode and the second readout electrode using the gas electron amplification unit 20 as a trigger. As shown in FIG. 4, the output signal of the first readout electrode is a reasonable value, but the output signal of the second readout electrode is reversed and is significantly different from the expectation.

This is because a negative signal is generated on the surface due to the dielectric action when a large amount of electrons move due to the electron avalanche toward the double-sided flexible substrate, but a positive charge appears due to the movement of the charge accumulated on the back surface. It is estimated to be. Although it is possible to use this signal, this signal is not stable. Further, it is considered that the signal shape itself changes depending on how much charge is accumulated. However, it may be detected in the future if the signal processing is devised. As a result of considering a reliable method, the inventor found the following.

  A large amount of electrons due to an electron avalanche reaches the surface of the double-sided flexible substrate, and charges accumulate in the insulator. This charge interferes with signal detection on the back surface. Therefore, it is possible to detect the signal on the back side by electromagnetic induction by reducing the charge accumulated in the insulator by providing a charge eliminating means and by the electromagnetic avalanche.

  It is structurally suitable for the static eliminating means to add a high resistance body to the gas electron amplifier side of the insulator. Therefore, as described above, the film added with the carbon paint is used as the static elimination means 80 in the case where the high resistance is added. However, the charge eliminating means may have an insulation resistance capable of gradually discharging the charge accumulated in the first readout electrode insulator within a predetermined time.

  In this way, the static eliminating means 80 is provided by the film in which the carbon coating material is applied to the surface of the double-sided flexible substrate 52. The results measured in this state are shown in FIG. Similarly, FIG. 5 shows output signals from the first readout electrode and the second readout electrode using the gas electron amplification unit 20 as a trigger. As shown in FIG. 5, it was found that the expected signals could be obtained for both the first readout electrode and the second readout electrode, and the prospect of practical use was obtained.

  FIG. 6 shows a two-dimensional image by X-rays detected by the gas radiation detector according to the present invention. FIG. 6 shows an example with 80 readout electrodes on one side, and it was found that it can be used for image reproduction.

  As described above, it has become possible to provide a gas radiation detector that employs a readout electrode using a flexible substrate technique that is generally used in the electronics industry. It is easy to manufacture because it uses the technology commonly used in the electronics industry. Therefore, the cost can be reduced. In this embodiment, it is manufactured at a pitch of 400 μm, but it is possible to easily manufacture a fine readout pattern that is difficult to manufacture by the conventional method. Further, since the pitch of the gas electron amplifying unit is 140 μm at present, it is possible to manufacture a readout electrode with a pitch of 100 μm that is sufficiently accurate for detecting an electron avalanche generated in the gas electron amplifying unit.

  In addition, since flexible substrate technology is used, in the application of curved two-dimensional gas radiation detectors such as PET, it is arranged to cover the whole body of the human body to be examined by arranging many detectors of about 30 cm x 30 cm. You can also

<Example 2>
The second embodiment relates to a two-dimensional gas radiation detector as in the first embodiment. In the special case of the first embodiment, it can be detected when the position cannot be specified in two dimensions.

  FIG. 7 is a conceptual explanatory diagram of another embodiment of the read electrode according to the present invention. As shown in FIG. 7, the configuration of the first embodiment shown in FIG. The third read electrode uniformly detects the occurrence of an avalanche extending across the first read electrode element ST1j and the second read electrode element ST2k as shown by the one-dot chain line in FIG. A plurality of parallel electrode elements ST3m that can be formed are provided on the flexible substrate 92. The flexible substrate 92 is fixed to the lower side of the flexible substrate 52 so as to be in the positional relationship of FIG. An electronic circuit A3m that can detect a signal is connected to each electrode element ST3m.

  In the case of the special case of the first embodiment, when an electronic avalanche occurs at the two positions (94, 95) in FIG. 7 at the same time, two positions (96, 96) also correspond to the two-dimensional case. Although not specified, it further includes a third read electrode element ST3m extending across the first read electrode and the second read electrode along the third direction as shown in FIG. Thus, the position where the electronic avalanche has occurred can be specified.

  In this way, it is possible to provide a two-dimensional gas radiation detector that can detect a two-dimensional image more accurately.

  As mentioned above, although demonstrated using the Example of this invention, the technical scope of this invention is not limited to the range as described in the said Example. Various modifications or improvements can be added to the above embodiment. It is apparent from the scope of the claims that the embodiments added with such changes or improvements can be included in the technical scope of the present invention. Examples of modifications of the present invention are illustrated below.

<Modification 1>
Although the two-dimensional gas radiation detector has been mainly described above, it can be similarly applied to a one-dimensional gas radiation detector. The present invention can also be applied to a gas radiation detector having a more complicated structure.

<Modification 2>
In the first embodiment, the flexible substrate has been mainly described. However, it can also be realized with a normal electronic circuit substrate. Moreover, it is realizable also by combining a flexible substrate and a normal electronic circuit board.

<Modification 3>
In Example 1, although the example which has exposed metal foil on both surfaces in the double-sided flexible board | substrate was mainly demonstrated, it can apply also to the flexible board | substrate which does not expose metal foil. Moreover, it is applicable also to the board | substrate which exposed only one side.

<Modification 4>
Although the first embodiment has been described by applying a carbon paint as a charge eliminating unit, other materials having equivalent performance may be used. For example, a paint made of copper oxide or chromium oxide may be used. Furthermore, a film having an equivalent thickness may be fixed instead of being applied. In addition, as the insulator of the first readout electrode, an insulator having an insulation resistance capable of gradually decreasing the charge accumulated within a predetermined time can be adopted. Further, in addition to the first readout electrode, a static eliminating unit may be used for another readout electrode.

<Modification 5>
In the first embodiment, the conductive strip (Stripping) has been mainly described as the conductive electrode, but other means capable of detecting an avalanche can also be applied. In particular, the generated avalanche can be replaced by other means capable of detecting as electromagnetic induction (electromagnetic wave).

  Non-destructive inspection measuring devices that detect two-dimensional positions with high transparency, such as X-rays and gamma rays, and single photon emission type computers such as PET and SPECT (Single Photon Emission Computed Tomography) It can be used for medical devices that use gamma rays such as tomography, and devices that can accurately measure the incident position of neutrons two-dimensionally.

It is a figure which shows the outline of a structure of the gas radiation detector which concerns on this invention. It is a specific embodiment realized by the flexible substrate of the two-dimensional readout electrode according to the present invention. It is a conceptual explanatory drawing of the Example of the read-out electrode which concerns on this invention. It is a figure showing the output signal of the two-dimensional read-out electrode by the double-sided flexible substrate which does not apply a static elimination means. It is a figure showing the output signal of the two-dimensional readout electrode which concerns on this invention. It is a figure showing the image detected by the gas radiation detector which concerns on this invention. It is a conceptual explanatory drawing of another Example of the read-out electrode which concerns on this invention. 1 is a schematic diagram of the structure of a GEM chamber proposed by Sauri. It is the schematic of the structure of a GEM chamber. It is a figure explaining an example and a principle of the double-sided flexible substrate of a gas electron amplification part. It is a figure explaining the structure of the read-out board | substrate by a prior art. It is a figure which shows the example of a manufacturing process of the reading substrate by a prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Gas radiation detector 10 Drift electrode 20 Gas electron amplification part 30 Read board 50 Read electrode 51 Insulator 52 Flexible board 53-56 Connector 58 Board | substrate 61 Insulator 63-66 Connector 70 Frame 80 Static elimination means 92 Flexible board A1j Electronic circuit A2k electronic circuit A3m electronic circuit ST1j first electrode element ST2k second electrode element ST3m third electrode element

Claims (7)

A gas radiation detector for detecting primary electrons generated by ionizing radiation in a gas at a readout electrode,
A drift electrode that generates an electric field that accelerates the generated electrons;
A gas electron amplifying unit whose electric field strength is locally increased in order to generate an electron avalanche in the gas from one of the primary electrons;
The readout electrode has a large number of electrode elements that can uniformly detect that an electron avalanche has occurred, an insulator that insulates each electrode element, and a charge removal means that relaxes the charge accumulated in the insulator,
Gas radiation detector equipped with. A two-dimensional gas radiation detector for detecting primary electrons generated by ionizing radiation in a gas with a two-dimensional readout electrode,
A drift electrode that generates an electric field that accelerates the generated electrons;
A gas electron amplifying unit whose electric field strength is locally increased in order to generate an electron avalanche in the gas from one of the primary electrons;
The two-dimensional readout electrode is
A plurality of parallel electrode elements that face the gas electron amplifying unit and extend along a first predetermined direction and can uniformly detect that an electron avalanche has occurred, and an insulator that insulates each electrode element And a first readout electrode having a charge eliminating means for relaxing charges accumulated in the insulator,
Uniformly, an electron avalanche located in the gas electron amplifying portion of the first readout electrode and extending along the second predetermined direction across the first predetermined direction has occurred. A second readout electrode having a plurality of parallel electrode elements that can be detected and an insulator that insulates each electrode element;
A two-dimensional gas radiation detector.   An electronic avalanche extending across the first read electrode and the second read electrode along a third direction intermediate the first predetermined direction and the second predetermined direction occurs. The two-dimensional gas radiation detector according to claim 2, further comprising a third readout electrode having a plurality of parallel electrode elements capable of uniformly detecting the above and an insulator that insulates each electrode element.   The gas radiation detector according to any one of claims 1 to 3, wherein the electrode element is a conductive strip.   The gas radiation detector according to any one of claims 1 to 4, wherein the static elimination unit is a unit in which a high resistance is added to the gas electron amplification unit side of the insulator.   The gas radiation detector according to claim 5, wherein the high-resistance material added is a film coated with a carbon paint. 4. The two-dimensional gas according to claim 2, wherein the charge eliminating unit is a unit that employs an insulator having an insulation resistance capable of gradually discharging charges accumulated within a predetermined time as the insulator of the first readout electrode. Radiation detector.