JP2012118050A - Radiographic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a radiographic device capable of saving a time and effort required for sealing an electrode part again and also suppressing deterioration of moisture-proof properties at the electrode part.SOLUTION: In a state where connectors 38, 40 of a radiation detector are connected to flexible cables 42, 44, the radiation detector and connection parts of the flexible cables 42, 44 and the connectors 38, 40 are covered with a protective film 100 to seal them integrally, which eliminates the need for sealing an electrode part again and enables suppression of deterioration of moisture-proof properties at the electrode part.

Description

  The present invention relates to a radiation imaging apparatus, and more particularly, to a radiation imaging apparatus that captures a radiation image indicated by radiation emitted from a radiation source and transmitted through a subject.

  In recent years, radiation detectors such as flat panel detectors (FPDs) that can arrange radiation sensitive layers on TFT (Thin Film Transistor) active matrix substrates and convert radiation directly into digital data have been put into practical use. A radiographic apparatus that captures a radiographic image represented by irradiated radiation has been put to practical use. The radiography apparatus using this radiation detector can confirm an image immediately compared to a radiography apparatus using a conventional imaging plate, and also performs fluoroscopic imaging (moving image shooting) for continuously capturing radiographic images. There is an advantage that you can.

  Various types of radiation detectors of this type have been proposed. For example, an indirect conversion method in which radiation is converted into light by a scintillator and then converted into electric charge in a semiconductor layer such as a photodiode, or radiation is converted into amorphous selenium. There is a direct conversion method for converting into electric charge in a semiconductor layer. In the radiation imaging apparatus, the electric charge accumulated in the radiation detector is read as an electric signal, and the read electric signal is amplified by an amplifier and then converted into digital data by an A / D (analog / digital) converter.

  By the way, in order to protect the radiation detector, the radiation detector may be sealed by coating with an organic material such as Parylene (registered trademark). For example, CsI (cesium iodide) used as a scintillator has deliquescence. For this reason, Patent Documents 1 and 2 propose that a scintillator is deposited on a sensor element substrate and then sealed with an organic material such as Parylene (registered trademark). Coating with an organic material such as Parylene (registered trademark) is used to seal a radiation detector using a scintillator because it can form a protective film that is uniform and has no pinholes up to the depths of minute gaps.

JP 2000-284053 A JP 2004-335870 A

  By the way, the radiation detector is provided with an electrode portion for connecting to an external circuit such as a drive circuit, and a connection wiring such as a flexible substrate for connecting to the external circuit is connected to the electrode portion.

  For this reason, as described in Patent Documents 1 and 2, when the radiation detector is coated and sealed with an organic material, it is necessary to remove the coating of the electrode portion in order to connect the connection wiring.

  Thus, when the coating of the electrode part is removed, the moisture resistance deteriorates in the electrode part. For this reason, it is necessary to re-seal the electrode part of the radiation detector after connecting the connection wiring to the electrode part, and it takes time and effort, and even if it is sealed again, the moisture resistance at the electrode part may be reduced. There is.

  The present invention has been made in view of the above-described facts, and an object of the present invention is to provide a radiographic apparatus that suppresses a decrease in moisture resistance at the electrode part while omitting the trouble of sealing the electrode part again.

  In order to achieve the above object, the radiation imaging apparatus according to claim 1 is capable of capturing a radiation image represented by incident radiation, inputting a control signal for capturing the radiation image, and capturing the captured radiation image. A radiation detector provided with an electrode unit for outputting an image signal indicating the above, a connection wiring electrically connected to the electrode unit, through which at least one of the control signal or the image signal flows, and an organic material A protective film integrally covering and covering the connection portion of the radiation detector and the connection wiring with the electrode portion in a state where the connection wiring is connected to the electrode portion of the radiation detector. ing.

  According to the first aspect, the radiation detector is capable of capturing a radiation image represented by the incident radiation, and also includes an input of a control signal for capturing the radiation image and an image indicating the captured radiation image. An electrode portion for outputting a signal is provided. A connection wiring is electrically connected to the electrode portion of the radiation detector, and at least one of the control signal and the image signal flows through the connection wiring.

  And according to Claim 1, in the state which connected the connection wiring to the electrode part of the radiation detector, the connection part with the electrode part of a radiation detector and a connection wiring is covered with the protective film, and is sealed integrally. Yes.

  As described above, according to the first aspect of the present invention, the connection portion between the radiation detector and the connection wiring and the electrode portion is covered with the protective film in a state where the connection wiring is connected to the electrode portion of the radiation detector. Since sealing is performed, the trouble of sealing the electrode portion again can be saved. Moreover, since the connection part of the electrode part of connection wiring is covered and sealed with a protective film, the fall of moisture resistance in an electrode part can be suppressed.

  According to the present invention, as in the invention described in claim 2, the connection wiring is a flexible wiring board provided with an integrated circuit that performs at least one of generation of the control signal and signal processing on the image signal. The protective film may cover and seal the integrated circuit portion provided on the wiring board.

  In the present invention, the organic material is preferably Parylene (registered trademark) as in the invention described in claim 3.

  In the present invention, it is preferable that the thickness of the protective film is 5 μm to 50 μm.

  Further, in the present invention, the radiation detector includes a photoconductive portion that directly converts incident radiation into an electric charge in a state where a bias voltage is applied, and an application for applying the bias voltage to the photoconductive portion. A direct-conversion radiation detector provided with an electrode unit, and in this case, the present invention provides the bias voltage applied to the photoconductive unit as described in claim 5. In a state in which the connection wiring for application for applying a voltage is connected to the application electrode portion of the radiation detector, the connection portion between the connection wiring for application and the application electrode portion is also covered and integrally sealed. It can be constituted as follows.

Further, in the present invention, the radiation detector includes a photoconductive portion that directly converts incident radiation into an electric charge in a state where a bias voltage is applied, and an application for applying the bias voltage to the photoconductive portion. In this case, the protective film may be the application electrode of the radiation detector. In this case, the protective film may be the application electrode of the radiation detector. The structure which covers a part other than a part and is integrally sealed may be sufficient.

  ADVANTAGE OF THE INVENTION According to this invention, the fall of moisture resistance in an electrode part can be suppressed, omitting the effort which seals an electrode part again.

It is a permeation | transmission perspective view which shows the internal structure of the electronic cassette concerning embodiment. It is sectional drawing which showed typically the structure of the radiation detector 60 which concerns on embodiment. It is sectional drawing which showed schematically the structure of TFT formed in the TFT substrate which concerns on embodiment, and a storage capacitor. It is a top view which shows the structure of the radiation detector 60 which concerns on embodiment. It is sectional drawing which shows the structure inside the electronic cassette which concerns on embodiment. It is a cross-sectional side view for demonstrating the surface reading system and back surface reading system of the radiation to a radiation detector. It is sectional drawing which showed roughly the cross-sectional structure of the radiation detector in which the protective film which concerns on embodiment was formed. It is the expanded sectional view which showed the cross-sectional structure of the connection part of the connector of a radiation detector and the flexible cable in which the protective film which concerns on 1st Embodiment was formed. It is the expanded sectional view which showed the state except the protective member of the electrode 94 part of the flexible cable. It is sectional drawing which showed schematically the cross-sectional structure of the connection part of the connector and flexible cable of a radiation detector in which the protective film which concerns on 2nd Embodiment was formed. It is a top view which shows the formation range of the protective film in 1st Embodiment. It is a top view which shows the formation range of the protective film in 2nd Embodiment. It is sectional drawing which shows schematic structure of the radiation detector of a direct conversion system. It is a top view which shows an example of the formation range of the protective film in the radiation detector of a direct conversion system. It is a top view which shows the other example of the formation range of the protective film in the radiation detector of a direct conversion system. It is a top view which shows the other example of the formation range of the protective film in the radiation detector of a direct conversion system. It is a top view which shows the other example of the formation range of the protective film in the radiation detector of a direct conversion system.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings. Here, a description will be given of an example in which the present invention is applied to a portable radiation imaging apparatus (hereinafter also referred to as “electronic cassette”).

[First Embodiment]
FIG. 1 shows a configuration of an electronic cassette 10 according to the present exemplary embodiment.

  As shown in the figure, the electronic cassette 10 includes a housing 55 made of a material that transmits the radiation X, and has a waterproof and airtight structure. When the electronic cassette 10 is used in an operating room or the like, there is a risk that blood and other germs may adhere. Therefore, one electronic cassette 10 can be used repeatedly by sterilizing and cleaning the electronic cassette 10 as a waterproof and airtight structure as necessary.

  A radiation detector 60 that detects the radiation X transmitted through the subject in order from the irradiation surface 56 side of the housing 55 irradiated with the radiation X transmitted through the subject during imaging. , And a control board 22 for controlling the radiation detector 60 is sequentially provided. The irradiation surface 56 corresponds to a range where the radiation detector 60 is arranged, and an area where a radiation image is captured by the radiation detector 60 is an imaging area 56A.

  FIG. 2 is a cross-sectional view schematically showing the configuration of the radiation detector 60 according to the present exemplary embodiment.

  The radiation detector 60 includes a TFT active matrix substrate (hereinafter referred to as “TFT substrate”) 66 in which a thin film transistor (TFT) 70 and a storage capacitor 68 are formed on an insulating substrate 64. I have.

  On the TFT substrate 66, a scintillator 71 that converts incident radiation into light is disposed.

  As the scintillator 71, for example, CsI: Tl, GOS (Gd2O2S: Tb) can be used. The scintillator 71 is not limited to these materials. The wavelength range of light emitted from the scintillator 71 is preferably the visible light range (wavelength 360 nm to 830 nm), and in order to enable monochrome imaging by the radiation detector 60, the wavelength range of green is included. Is more preferable.

  Here, in the present embodiment, the scintillator 71 is a columnar crystal such as CsI: Tl, for example. The scintillator 71 is formed by vapor-depositing a material such as CsI: Tl on the vapor deposition substrate 73, a non-columnar crystal region 71A is formed on the vapor deposition substrate 73 side, and a columnar crystal is formed on the tip side (TFT substrate 66 side). A columnar crystal region 71B is formed.

  Thus, when forming the scintillator 71 by vapor deposition, the vapor deposition substrate 73 is often an Al plate in terms of X-ray transmittance and cost, handling properties during vapor deposition, prevention of warpage due to its own weight, and deformation due to radiant heat. Therefore, a certain thickness (about several mm) is required.

  The scintillator 71 is disposed so that the columnar crystal region 71B side faces the TFT substrate 66, and is adhered to the TFT substrate 66.

  The insulating substrate 64 may be any substrate as long as it absorbs little radiation. For example, a glass substrate, a transparent ceramic substrate, or a resin substrate can be used. The insulating substrate 64 is not limited to these materials.

  The TFT substrate 66 is formed with a sensor portion 72 that generates charges when light converted by the scintillator 71 is incident thereon. In the TFT substrate 66 according to the present embodiment, the TFT 70 and the sensor unit 72 are formed so as to overlap each other. Thereby, the light receiving area of the light from the scintillator 71 in the sensor unit 72 can be increased. A flattening layer 67 for flattening the TFT substrate 66 is formed on the TFT substrate 66. An adhesive layer 69 for bonding the scintillator 71 to the TFT substrate 66 is formed between the TFT substrate 66 and the scintillator 71 and on the planarizing layer 67.

  The sensor unit 72 includes an upper electrode 72A, a lower electrode 72B, and a photoelectric conversion film 72C disposed between the upper and lower electrodes.

  The upper electrode 72A and the lower electrode 72B are formed using a highly light-transmitting material such as ITO (indium tin oxide) or IZO (zinc indium oxide) and have light transmittance.

  The photoelectric conversion film 72 </ b> C absorbs light emitted from the scintillator 71 and generates a charge corresponding to the absorbed light. The photoelectric conversion film 72C may be formed of a material that generates charges when irradiated with light. For example, the photoelectric conversion film 72C may be formed of amorphous silicon, an organic photoelectric conversion material, or the like. The photoelectric conversion film 72C containing amorphous silicon has a wide absorption spectrum and can absorb light emitted by the scintillator 71. If the photoelectric conversion film 72C includes an organic photoelectric conversion material, it has a sharp absorption spectrum in the visible range, and electromagnetic waves other than light emitted by the scintillator 71 are hardly absorbed by the photoelectric conversion film 72C, and radiation such as X-rays. Is effectively suppressed by the photoelectric conversion film 72C being absorbed.

  Examples of organic photoelectric conversion materials include quinacridone organic compounds and phthalocyanine organic compounds. For example, since the absorption peak wavelength in the visible region of quinacridone is 560 nm, if quinacridone is used as the organic photoelectric conversion material and CsI: Tl is used as the material of the scintillator 71, the difference between the peak wavelengths can be within 5 nm. Thus, the amount of charge generated in the photoelectric conversion film 72C can be substantially maximized. Since the organic photoelectric conversion material applicable as the photoelectric conversion film 72C is described in detail in Japanese Patent Application Laid-Open No. 2009-32854, description thereof is omitted. The photoelectric conversion film 72C may be formed by further containing fullerenes or carbon nanotubes.

  FIG. 3 schematically shows the configuration of the TFT 70 and the storage capacitor 68 formed on the TFT substrate 66 according to the present embodiment.

  On the insulating substrate 64, corresponding to the lower electrode 72B, a storage capacitor 68 for storing the charge transferred to the lower electrode 72B, and a TFT 70 for converting the charge stored in the storage capacitor 68 into an electric signal and outputting it. Is formed. The region where the storage capacitor 68 and the TFT 70 are formed has a portion that overlaps with the lower electrode 72B in a plan view. With such a configuration, the storage capacitor 68 and the TFT 70 in each pixel portion, the sensor portion 72, and the like. Therefore, the storage capacitor 68, the TFT 70, and the sensor unit 72 can be arranged with a small area.

  The storage capacitor 68 is electrically connected to the corresponding lower electrode 72B through a wiring made of a conductive material formed through an insulating film 65A provided between the insulating substrate 64 and the lower electrode 72B. Yes. Thereby, the charges collected by the lower electrode 72B can be moved to the storage capacitor 68.

  In the TFT 70, a gate electrode 70A, a gate insulating film 65B, and an active layer (channel layer) 70B are stacked, and a source electrode 70C and a drain electrode 70D are formed on the active layer 70B at a predetermined interval. The active layer 70B can be formed of, for example, amorphous silicon, amorphous oxide, organic semiconductor material, carbon nanotube, or the like. In addition, the material which comprises the active layer 70B is not limited to these.

  As the amorphous oxide constituting the active layer 70B, an oxide containing at least one of In, Ga, and Zn (for example, In—O-based) is preferable, and at least two of In, Ga, and Zn are used. Are more preferable (for example, In—Zn—O, In—Ga—O, and Ga—Zn—O), and oxides including In, Ga, and Zn are particularly preferable. As the In—Ga—Zn—O-based amorphous oxide, an amorphous oxide whose composition in a crystalline state is represented by InGaO 3 (ZnO) m (m is a natural number of less than 6) is preferable, and InGaZnO 4 is particularly preferable. More preferred. The amorphous oxide that can form the active layer 70B is not limited to these.

  Examples of the organic semiconductor material that can form the active layer 70B include, but are not limited to, phthalocyanine compounds, pentacene, vanadyl phthalocyanine, and the like. In addition, about the structure of a phthalocyanine compound, since it is demonstrated in detail in Unexamined-Japanese-Patent No. 2009-212389, description is abbreviate | omitted.

  If the active layer 70B of the TFT 70 is formed of an amorphous oxide, an organic semiconductor material, or a carbon nanotube, noise such as X-rays is not absorbed, or even if it is absorbed, the amount of noise remains extremely small. Can be effectively suppressed.

  Further, when the active layer 70B is formed of carbon nanotubes, the switching speed of the TFT 70 can be increased, and the TFT 70 having a low light absorption degree in the visible light region can be formed. In addition, when forming the active layer 70B with carbon nanotubes, the performance of the TFT 70 is remarkably deteriorated only by mixing a very small amount of metallic impurities into the active layer 70B. Therefore, extremely high purity carbon nanotubes are separated by centrifugation or the like.・ It needs to be extracted and formed.

  Here, any of the amorphous oxide, the organic semiconductor material, the carbon nanotube, and the organic photoelectric conversion material forming the photoelectric conversion film 72 </ b> C constituting the active layer 70 </ b> B of the TFT 70 can be formed at a low temperature. Therefore, the insulating substrate 64 is not limited to a substrate having high heat resistance such as a quartz substrate and a glass substrate, and a flexible substrate such as plastic, aramid, or bionanofiber can also be used. Specifically, flexible materials such as polyesters such as polyethylene terephthalate, polybutylene phthalate, polyethylene naphthalate, polystyrene, polycarbonate, polyethersulfone, polyarylate, polyimide, polycycloolefin, norbornene resin, poly (chlorotrifluoroethylene), etc. A conductive substrate can be used. If such a plastic flexible substrate is used, it is possible to reduce the weight, which is advantageous for carrying around, for example. The insulating substrate 64 includes an insulating layer for ensuring insulation, a gas barrier layer for preventing permeation of moisture and oxygen, an undercoat layer for improving flatness or adhesion to electrodes, and the like. May be provided.

  Since aramid can be applied at a high temperature process of 200 ° C. or more, the transparent electrode material can be cured at a high temperature to reduce the resistance, and can also be used for automatic mounting of a driver IC including a solder reflow process. Moreover, since aramid has a thermal expansion coefficient close to that of ITO (indium tin oxide) or a glass substrate, warping after production is small and it is difficult to crack. In addition, aramid can form a substrate thinner than a glass substrate or the like. Note that the insulating substrate 64 may be formed by stacking an ultrathin glass substrate and aramid.

  Bionanofiber is a composite of cellulose microfibril bundles (bacterial cellulose) produced by bacteria (Acetobacter Xylinum) and a transparent resin. The cellulose microfibril bundle has a width of 50 nm and a size of 1/10 of the visible light wavelength, and has high strength, high elasticity, and low thermal expansion. By impregnating and curing a transparent resin such as an acrylic resin or an epoxy resin in bacterial cellulose, a bio-nanofiber having a light transmittance of about 90% at a wavelength of 500 nm can be obtained while containing 60-70% of the fiber. Bionanofiber has a low coefficient of thermal expansion (3-7ppm) comparable to silicon crystals, and is as strong as steel (460MPa), highly elastic (30GPa), and flexible, compared to glass substrates, etc. A thin insulating substrate 64 can be formed.

  FIG. 4 is a plan view showing the configuration of the radiation detector 60 according to the present exemplary embodiment.

  The TFT substrate 66 includes a pixel 74 including the sensor unit 72, the storage capacitor 68, and the TFT 70 described above in a certain direction (row direction in FIG. 4) and a cross direction with respect to the certain direction (column direction in FIG. 4). Are provided two-dimensionally.

  The TFT substrate 66 includes a plurality of gate wirings 76 extending in a certain direction (row direction) for turning on / off the TFTs 70, and an on-state TFT 70 extending in a crossing direction (column direction). A plurality of data wirings 78 are provided for reading out charges through the wirings.

  The radiation detector 60 is flat and has a quadrilateral shape with four sides on the outer edge in plan view. Specifically, it is formed in a rectangular shape.

  As shown in FIG. 2, the radiation detector 60 according to the present exemplary embodiment is formed by attaching a scintillator 71 to the surface of such a TFT substrate 66.

  The scintillator 71 converts radiation X such as irradiated X-rays and γ-rays into light. The sensor unit 72 receives the light emitted from the scintillator 71 and accumulates electric charges.

  An electric signal (image signal) indicating a radiographic image flows in each data line 78 according to the amount of charge accumulated in the sensor unit 72 when any of the TFTs 70 connected to the data line 78 is turned on. It is like that.

  A plurality of connectors 38 for connection are arranged side by side at one end of the radiation detector 60 in the direction of the data wiring 78, and a plurality of connectors 40 are arranged at one end of the radiation detector 60 in the direction of the gate wiring 76. Each data wiring 78 is connected to the connector 38 by a predetermined number, and each gate wiring 76 is connected to the connector 40 by a predetermined number.

  One end of a flexible cable 42 is electrically connected to these connectors 38. One end of the flexible cable 44 is electrically connected to the connector 40.

  The flexible cable 42 and the flexible cable 44 are electrically connected to the control board 22.

  The control board 22 is provided with a control unit 46 that controls the imaging operation by the radiation detector 60 and the signal processing for the electric signal flowing through each data wiring 78. The control unit 46 includes a signal detection circuit 48, And a scan signal control circuit 50.

  The signal detection circuit 48 is provided with a plurality of connectors 52, and the other end of the flexible cable 42 described above is electrically connected to these connectors 52. The signal detection circuit 48 includes an amplification circuit for amplifying an input electric signal for each data wiring 78. With this configuration, the signal detection circuit 48 amplifies and detects the electric signal input from each data wiring 78 by the amplification circuit, and is stored in each sensor unit 72 as information of each pixel constituting the image. Detect the amount of charge.

  On the other hand, the scan signal control circuit 50 is provided with a plurality of connectors 54, and the other end of the flexible cable 44 described above is electrically connected to these connectors 54. A control signal for turning on / off the TFT 70 can be output to each gate wiring 76.

  FIG. 5 is a cross-sectional view showing an internal configuration of the electronic cassette 10 according to the present exemplary embodiment.

  A housing 55 of the electronic cassette 10 is constituted by a front panel 57 and a back panel 58. The front panel 57 includes a top plate 57A that constitutes the photographing surface 56, and a holding portion 57B that holds the top plate 57A.

  The radiation detector 60 is arranged so that the TFT substrate 66 side faces the surface opposite to the surface on which the radiation X of the top plate 57A of the housing 55 is incident.

  Here, as shown in FIG. 6, the radiation detector 60 is irradiated with radiation from the side on which the scintillator 71 is formed, and reads a radiation image by the TFT substrate 66 provided on the back side of the incident surface of the radiation. In the case of the so-called back side scanning method (so-called PSS (Penetration Side Sampling) method), the scintillator 71 emits light more strongly on the upper surface side (the opposite side of the TFT substrate 66) of the scintillator 71, and radiation is irradiated from the TFT substrate 66 side. In the case of a so-called surface reading method (so-called ISS (Irradiation Side Sampling) method) in which a radiation image is read by the TFT substrate 66 provided on the surface side of the radiation incident surface, the radiation transmitted through the TFT substrate 66 is transmitted. The light enters the scintillator 71 and the TFT substrate 66 side of the scintillator 71 emits light more intensely. Electric charges are generated by the light generated by the scintillator 71 in each sensor unit 72 provided on the TFT substrate 66. For this reason, since the radiation detector 60 is closer to the light emission position of the scintillator 71 with respect to the TFT substrate 66 when the front side reading method is used than when the rear side reading method is used, the resolution of the radiation image obtained by imaging is higher. high.

  In the present embodiment, as shown in FIG. 5, a radiation detector 60 is arranged inside the electronic cassette 10 so as to be a surface reading method for the radiation X incident from the imaging surface 56.

  When taking a radiographic image, the radiation detector 60 is irradiated with the radiation X transmitted through the subject. The irradiated radiation X is converted into light by the scintillator 71 and irradiated to the sensor unit 72. The sensor unit 72 receives the light emitted from the scintillator 71 and accumulates electric charges.

  At the time of image reading, an ON signal (+10 to 20 V) is sequentially applied from the scan signal control circuit 50 to the gate electrode of the TFT 70 of the radiation detector 60 through the gate wiring 76. Accordingly, when the TFTs 70 of the radiation detector 60 are sequentially turned on, an electrical signal corresponding to the amount of charge accumulated in the sensor unit 72 flows out to the data wiring 78. The signal detection circuit 48 detects the amount of electric charge accumulated in each sensor unit 72 based on the electrical signal that has flowed out to the data wiring 78 of the radiation detector 60 as information of each pixel constituting the image. Thereby, image information indicating an image indicated by the radiation applied to the radiation detector 60 is obtained.

  Next, sealing of the radiation detector 60 according to the present embodiment will be described.

  FIG. 7 schematically shows a cross-sectional configuration of the radiation detector 60. FIG. 8 shows a cross-sectional configuration of a connection portion between the connector 38 and the flexible cable 42 of the radiation detector 60 according to the first embodiment. In addition, since it is the same structure also about the connection part of the connector 40 of the radiation detector 60 and the flexible cable 44, the code | symbol of the connector 40 and the flexible cable 44 is attached | subjected and demonstrated to a corresponding location.

  The radiation detector 60 includes a scintillator 71 made of a columnar crystal of CsI: Tl formed by vapor-depositing a material such as CsI: Tl on a vapor deposition substrate 73, and a TFT with the columnar crystal region 71B side facing the TFT substrate 66. Bonded to the substrate 66.

  The connector 38 (40) of the TFT substrate 66 is provided with an anisotropic conductive film (ACF (Anisotropic Conductive Film)) 90B on the electrode 90A. An electrode 92 at one end of the flexible cable 42 is connected to the connector 38 of the TFT substrate 66, and an electrode 92 at one end of the flexible cable 44 is connected to the connector 40.

  A peelable protective member is provided on the electrode 94 on the other end side connected to the control board 22 of the flexible cables 42 and 44. In the present embodiment, the mask 96 is covered with a mask 96 after being covered with a cover 96 made of a resin such as PET (polyethylene terephthalate).

  The radiation detector 60 according to the present embodiment has a protective film so as to integrally cover the radiation detector 60 and the flexible cables 42 and 44 in a state where the flexible cables 42 and 44 are connected to the connectors 38 and 40 as described above. 100 is formed.

  The protective film 100 is made of an organic material having a barrier property against moisture in the air, such as polyparaxylylene resin (for example, parylene (registered trademark)), and is a vapor phase such as thermal CVD (Chemical vapor deposition). It is formed by polymerization or the like. The protective film 100 can also be a laminated structure of an organic film and an inorganic film. Examples of the inorganic film material include a silicon nitride (SiNx) film, a silicon oxide (SiOx) film, and a silicon oxynitride (SiOxNy). A film, Al 2 O 3 or the like is preferable.

  The film thickness of the protective film 100 is preferably about 5 to 50 μm, and more preferably about 10 to 30 μm. When the film thickness is less than 5 μm, the moisture-proof effect is not exhibited, and when it exceeds 50 μm, the flexibility of the flexible cables 42 and 44 cannot be ensured.

  Thus, by forming the protective film 100 in a state where the flexible cables 42 and 44 are connected to the radiation detector 60, it is possible to prevent the moisture resistance at the connectors 38 and 40 from deteriorating. Moreover, the connection part of the connectors 38 and 40 and the flexible cables 42 and 44 can be protected with the radiation detector 60 by one sealing process.

  When the flexible cables 42 and 44 are connected to the control board 22, the masking tape 97 and the cover 96 are removed. As a result, as shown in FIG. 9, the flexible cables 42 and 44 are protected when the connecting terminal portion is connected to the control board 22 because the protective film 100 is removed together with the masking tape 97 and the electrode 94 portion is exposed. Insulation by the film 100 can be prevented (see also FIG. 11).

  As described above, according to the present embodiment, the radiation detector 60 and the flexible cables 42 and 44 and the connectors 38 and 40 are connected in a state where the flexible cables 42 and 44 are connected to the connectors 38 and 40 of the radiation detector 60. Since the portion is covered with the protective film 100 and integrally sealed, it is possible to suppress a decrease in moisture resistance in the connectors 38 and 40 while omitting the trouble of sealing the connectors 38 and 40 again.

[Second Embodiment]
Next, a second embodiment will be described.

  Since the configuration of the electronic cassette 10 and the configuration of the TFT substrate 66 according to the second embodiment are the same as those of the first embodiment (see FIGS. 1 to 3), description thereof is omitted here.

  FIG. 10 shows a cross-sectional configuration of a connection portion between the connector 38 and the flexible cable 42 of the radiation detector 60 according to the second exemplary embodiment. In addition, since it is the same structure also about the connection part of the connector 40 of the radiation detector 60 and the flexible cable 44, the code | symbol of the connector 40 and the flexible cable 44 is attached | subjected and demonstrated to a corresponding location.

  In the present embodiment, the flexible cables 42 and 44 are respectively flexible wiring boards. In addition, the signal detection circuit 48 and the scan signal control circuit 50 are respectively integrated, and an amplifier IC (Integrated Circuit) 102 that functions as the signal detection circuit 48 is mounted on the flexible cable 42 by TCP (Tape Carrier Package), so that the scan signal control circuit The gate IC 104 functioning as 50 is TCP mounted on the flexible cable 44.

  Then, the radiation detector 60 according to the present exemplary embodiment includes the protective film 100 so as to integrally cover the radiation detector 60 and the flexible cables 42 and 44 in a state where the flexible cables 42 and 44 are connected to the connectors 38 and 40. Form.

  Accordingly, the amplifier IC 102 and the gate IC 104 mounted on the flexible cables 42 and 44 can be integrally sealed with the protective film 100 (see also FIG. 12).

  As described above, according to the present embodiment, the amplifier IC 102 and the gate IC 104 are mounted on the flexible cables 42 and 44, and the amplifier IC 102 and the gate IC 104 are also integrally sealed with the protective film 100, thereby The IC 104 can also be integrally protected, and noise from the outside can be prevented from entering the amplifier IC 102 and the gate IC 104.

  As mentioned above, although this invention was demonstrated using 1st, 2nd embodiment, the technical scope of this invention is not limited to the range as described in each said embodiment. Various modifications or improvements can be added to the above-described embodiments without departing from the gist of the invention, and embodiments to which the modifications or improvements are added are also included in the technical scope of the present invention.

  The above embodiments do not limit the invention according to the claims (claims), and all the combinations of features described in the embodiments are essential for the solution means of the invention. Is not limited. The embodiments described above include inventions at various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements. Even if some constituent requirements are deleted from all the constituent requirements shown in the embodiment, as long as an effect is obtained, a configuration from which these some constituent requirements are deleted can be extracted as an invention.

  For example, in each of the above embodiments, the case where the present invention is applied to the electronic cassette 10 which is a portable radiation imaging apparatus has been described. However, the present invention is not limited to this, and the stationary radiation imaging apparatus is used. You may apply to.

  In each of the above embodiments, the case where sealing is performed once with Parylene (registered trademark) in a state where the flexible cables 42 and 44 are connected to the connectors 38 and 40 of the radiation detector 60 has been described. Is not limited to this. For example, a protective film is formed on the entire scintillator 71 in which a columnar crystal of CsI: Tl is formed by vapor deposition on the vapor deposition substrate 73, sealing is performed once, and the scintillator 71 on which the protective film is formed and the TFT substrate 66 are bonded to each other. It is good also as what seals with parylene (trademark) etc. in the state which connected the flexible cables 42 and 44 to the connectors 38 and 40 of the board | substrate 66. FIG. If the thickness of the protective film 100 is increased in order to increase the moisture resistance of the scintillator 71, the flexibility of the flexible cables 42 and 44 cannot be secured. However, by sealing the scintillator 71 individually, the flexible cables 42 and 44 are sealed. It is possible to improve the moisture resistance of the scintillator 71 while ensuring the flexibility.

  In each of the above embodiments, the case where the present invention is applied to the indirect conversion type radiation detector 60 has been described, but the present invention is not limited to this. For example, the present invention may be applied to a direct conversion type radiation detector that directly converts radiation into electric charges and accumulates it by a photoconductive layer using amorphous selenium or the like.

An example of the direct conversion type radiation detector 120 is shown in FIG. In the radiation detector 120, a photoconductive layer 122 that converts incident radiation into charges is formed on the TFT substrate 124. As the photoconductive layer 122, amorphous Se, Bi ₁₂ MO ₂₀ (M: Ti, Si, Ge), Bi ₄ M ₃ O ₁₂ (M: Ti, Si, Ge), Bi ₂ O ₃ , BiMO ₄ (M: Nb, Ta, V), Bi ₂ WO ₆ , Bi ₂₄ B ₂ O ₃₉ , ZnO, ZnS, ZnSe, ZnTe, MNbO ₃ (M: Li, Na, K), PbO, HgI ₂ , PbI ₂ , CdS, CdSe , CdTe, BiI ₃ , GaAs, and the like are used, but they have high dark resistance, show good photoconductivity with respect to the irradiated radiation, and are low in temperature by vacuum deposition. An amorphous material capable of forming a large-area film is preferable.

  On the photoconductive layer 122, a bias electrode 126 is formed on the surface side of the photoconductive layer 122 to apply a bias voltage to the photoconductive layer 122. Similarly to the indirect conversion radiation detector 60, the TFT substrate 124 is formed with a charge collection electrode 128 that collects charges generated in the photoconductive layer 122. On the other hand, the TFT substrate 124 of the direct conversion type radiation detection panel is provided with a charge storage capacitor 130 for storing charges collected by the charge collection electrodes 128. The charges stored in each charge storage capacitor 130 are read when the switching element 132 is turned on.

  As an example, as shown in FIG. 14, the direct-conversion radiation detector 120 is provided with an application electrode unit 134 electrically connected to the bias electrode 126. One end portion of the application connection wiring 136 is bonded to the application electrode portion 134 with a conductive adhesive or the like. In addition, an electrode 138 is formed at the other end of the application connection wiring 136, and the electrode 138 is connected to a connector 142 provided in the voltage generator 140 that generates a bias voltage.

  The protective film 100 is formed in the radiation detector 120 in a state where one end portion of the application connection wiring 136 is bonded to the application electrode portion 134 and the electrode 138 of the application connection wiring 136 is covered with the cover 96 and the masking tape 97. These are performed so as to be integrally covered with the protective film 100. Thereby, it can suppress that the moisture proof property of the application electrode part 134 falls. In addition to the connection portion between the radiation detector 120, the connectors 38 and 40 and the flexible cables 42 and 44, the connection portion between the application electrode portion 134 and the application connection wiring 136 can be protected by a single sealing process. Can do.

  Note that the cover 96 and the masking tape 97 that cover the electrode 138 of the connection wiring 136 for application are removed after the protective film 100 is formed, and then the electrode 138 is connected to the connector 142 provided in the voltage generator 140. The The connecting portion between the electrode 138 and the connector 142 can be sealed with an insulating sealant.

  FIG. 14 shows a configuration in which the radiation detector 120 is electrically connected to the control board 22 via the flexible cables 42 and 44 as in the radiation detector 60 according to the first embodiment. However, the configuration is not limited to this, and the configuration shown in FIG. As in the second embodiment, the radiation detector 120 shown in FIG. 15 uses flexible cables 42 and 44 as flexible wiring boards, the amplifier IC 102 is connected to the flexible cable 42, and the gate IC 104 is connected to the flexible cable 44 and TCP. It is implemented.

  Also in the formation of the protective film 100 in this embodiment, one end portion of the application connection wiring 136 is bonded to the application electrode portion 134, and the electrode 138 of the application connection wiring 136 is covered with the cover 96 and the masking tape 97. These are performed so as to be integrally covered with the protective film 100. Thereby, it can prevent that the moisture resistance of the application electrode part 134 deteriorates. In addition to the connection portion between the radiation detector 120, the connectors 38 and 40 and the flexible cables 42 and 44, the connection portion between the application electrode portion 134 and the application connection wiring 136 can be protected by a single sealing process. Can do.

  Further, the formation of the protective film 100 is not limited to being performed in a state where one end portion of the application connection wiring 136 is bonded to the application electrode portion 134 as in the embodiments shown in FIGS. In FIGS. 16 and 17, the radiation detector 120, the connectors 38 and 40, and the flexible cables 42 and 44 are sealed with the protective film 100, and then the application connection wiring 144 having one end connected to the voltage generator 140. An embodiment in which the end portion is bonded to the application electrode portion 134 is shown. In this embodiment, the protective film 100 is formed in a state where the application electrode portion 134 is covered with the cover 96 and the masking tape 97, and the cover 96 and masking covering the application electrode portion 134 after the protective film 100 is formed. Tape 97 is removed. Thereafter, the other end portion of the application connection wiring 144 is bonded to the application electrode portion 134 with a conductive adhesive or the like, and the connection portion between the application connection wiring 144 and the application electrode portion 134 is insulatively sealed. Sealed by the agent.

  Moreover, although each said embodiment demonstrated the case where this invention was applied to the radiography apparatus which image | photographs a radiographic image by detecting an X-ray as a radiation, this invention is not limited to this. For example, the radiation to be detected may be any of gamma rays, particle rays, etc. in addition to X-rays.

  In each of the above embodiments, the case where the single control board 22 is formed has been described. However, the present invention is not limited to this embodiment, and the control board 22 is divided into a plurality of functions. May be. Furthermore, although the case where the control board 22 is arranged side by side in the vertical direction (thickness direction of the housing 55) with the radiation detector 60 has been described, the control board 22 may be arranged side by side with the radiation detector 60 in the horizontal direction. .

  In addition, the configuration described in each of the above embodiments is an example, and an unnecessary part is deleted, a new part is added, or a connection state is changed without departing from the gist of the present invention. It goes without saying that you can do it.

10 Electronic cassette 38 Connector (electrode part)
40 Connector (electrode part)
42 Flexible cable (connection wiring)
44 Flexible cable (connection wiring)
60 Radiation detector 100 Protective film 102 Amplifier IC
104 Gate IC

Claims (6)

A radiation detector provided with an electrode unit that can capture a radiation image represented by incident radiation, inputs a control signal for capturing the radiation image, and outputs an image signal indicating the captured radiation image; ,
A connection wiring that is electrically connected to the electrode portion and through which at least one of the control signal or the image signal flows;
A protective film made of an organic material and integrally covering the radiation detector and the connection portion of the connection wiring with the electrode portion in a state where the connection wiring is connected to the electrode portion of the radiation detector When,
A radiography apparatus comprising: The connection wiring is a flexible wiring board provided with an integrated circuit that performs at least one of generation of the control signal and signal processing on the image signal,
The radiation imaging apparatus according to claim 1, wherein the protective film covers and seals the integrated circuit portion provided on the wiring board. The radiation imaging apparatus according to claim 1, wherein the organic material is Parylene (registered trademark). The radiation imaging apparatus according to claim 1, wherein the protective film has a thickness of 5 μm to 50 μm. The radiation detector includes a photoconductive portion that directly converts incident radiation into an electric charge in a state where a bias voltage is applied, and an application electrode portion for applying the bias voltage to the photoconductive portion. Direct conversion type radiation detector,
The protective film includes the application connection wire and the application electrode portion in a state where an application connection wire for applying the bias voltage to the photoconductive portion is connected to the application electrode portion of the radiation detector. The radiation imaging apparatus according to claim 1, wherein the radiation imaging apparatus is also integrally sealed so as to cover a connection portion. The radiation detector includes a photoconductive portion that directly converts incident radiation into an electric charge in a state where a bias voltage is applied, and an application electrode portion for applying the bias voltage to the photoconductive portion. Direct conversion type radiation detector,
5. The radiation imaging apparatus according to claim 1, wherein the protective film covers and integrally seals a portion other than the application electrode portion of the radiation detector.

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