JP2009104043A - Cassette type radiation image solid-state detector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To secure portability, while omitting a handle and further, to increase image quality and service life by dispersing heat generation. <P>SOLUTION: A cassette type radiation image solid-state detector includes: a flat housing which is irradiated with radiation; a detector unit which is incorporated in the housing and converts the radiation made incident through the housing into an electric signal; and a plurality of rechargeable batteries which are incorporated in the housing and for supplying power to the detector unit. The plurality of rechargeable batteries are dispersed and arranged so that the centroid position of all the plurality of rechargeable batteries is roughly the center position of the housing, when viewed from a radiation incident surface side. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a cassette type radiation image solid state detector.

Conventionally, for the purpose of disease diagnosis and the like, a radiographic image taken using radiation, represented by an X-ray image, has been widely used.
Such medical radiographic images were conventionally taken using a screen film, but in recent years, digitization of radiographic images has been realized. For example, a stimulable phosphor layer forms radiation transmitted through a subject. After being stored in the photostimulable phosphor sheet, the photostimulable phosphor sheet is scanned with laser light, and thereby the photostimulated light emitted from the photostimulable phosphor sheet is photoelectrically converted to image data. A CR (Computed Radiography) apparatus for obtaining the above has been widely used.

  In radiographic imaging, a cassette (for example, see Patent Document 1 and Patent Document 2) in which a recording medium such as a screen film or a photostimulable phosphor sheet is housed is used. The CR cassette used for photographing with the CR apparatus can continue to use existing equipment such as a cassette holder or a bucky table that has been introduced to be compatible with conventional screen / film cassettes. In this way, the screen / film cassette is designed and manufactured following the JIS standard size. In other words, the cassette size compatibility is maintained, and the facility is effectively utilized and the image data is digitized.

  Recently, as a means for obtaining a medical radiation image, an FPD (Flat Panel Detector) is known as a detector for detecting irradiated radiation and acquiring it as digital image data. Housed portable imaging devices (portable FPDs) have come into practical use.

  Such a portable FPD includes, for example, a scintillator that converts radiation into light and a light detection unit that converts this light into an electric signal in a housing (housing), and is similar to a cassette for CR. In addition, both light weight and robustness (rigidity) are required.

For example, Patent Document 3 describes a portable FPD in which a grip handle is provided and the center of gravity of the housing is positioned on or near the center line of the grip handle in order to improve portability. .
JP 2005-121783 A JP 2005-114944 A JP 2004-246384 A

By the way, the portable FPD is held in various states by the patient at the time of photographing. However, if there is a handle, the posture of the patient and the holding operation are inevitably restricted.
In addition, since the center of gravity of the housing is positioned on or near the center line of the grip handle, when the contents are placed on or near the center line, heat is not concentrated and is difficult to disperse, resulting in a decrease in image quality and lifetime. Such a problem may occur.

  Accordingly, an object of the present invention is to ensure portability while omitting a handle, and to further improve image quality and life by dispersing heat generation.

A cassette type radiation image solid state detector according to the invention of claim 1,
A flat housing that is irradiated with radiation;
A detector unit built in the housing for converting the radiation incident through the housing into an electrical signal;
A plurality of rechargeable batteries built in the housing for supplying power to the detector unit;
The plurality of rechargeable batteries are arranged in a distributed manner such that the center of gravity positions of the plurality of rechargeable batteries as a whole are substantially center positions as viewed from the radiation incident surface side of the housing.

The invention according to claim 2 is the cassette type radiation image solid detector according to claim 1,
The detector unit has a plurality of circuit boards on which electronic components for converting the radiation into electrical signals are mounted;
The plurality of circuit boards are arranged in a distributed manner such that the center of gravity positions of the plurality of circuit boards as a whole are substantially the center positions when viewed from the radiation incident surface side of the housing.

According to the present invention, since the plurality of rechargeable batteries are dispersedly arranged so that the center of gravity of the entire plurality of rechargeable batteries is substantially the center position viewed from the radiation incident surface side of the housing, the housing without a handle. Even when the user grasps and holds the center of gravity, the balance of the center of gravity is stable and easy to carry. In particular, among the electronic component groups in the housing, since the rechargeable battery has a heavy feeling, it is possible to stabilize the weight balance only by distributing and disposing only the rechargeable battery.
And since the rechargeable battery which is also a heat generating body is distributedly arranged, heat generation is dispersed, and the image quality and life can be improved.

  Hereinafter, an embodiment of a cassette type radiation image solid state detector according to the present invention will be described with reference to FIGS. 1 to 13. However, the scope of the invention is not limited to the illustrated examples.

FIG. 1 is a perspective view of a cassette type radiation image solid-state detector (hereinafter referred to as “cassette type detector”) in the present embodiment.
A cassette type detector 1 in the present embodiment is a cassette type flat panel detector (hereinafter referred to as “FPD”), and the cassette type detector 1 detects irradiated radiation and outputs digital image data. And a flat housing 3 that houses the detector unit 2 therein.

FIG. 2 is an exploded perspective view of the housing 3 in the present embodiment.
As shown in FIG. 2, the housing 3 has a bottom surface portion 41 and a side wall portion 42 and is formed in a substantially box shape. When the cassette type detector 1 is used for imaging, an opening 48 is formed on the radiation incident side. And a front member 5 disposed on the radiation incident side of the cassette type detector 1.

  The front member 5 includes a flat portion 51 that is a rectangular portion formed in a rectangular shape, and a bent rising portion (side wall portion) 52 that is configured integrally with the flat portion 51. Similarly, it is formed in a box shape. The front member 5 has an opening 58 on the side opposite to the radiation incident side when the cassette type detector 1 is used for imaging, and functions as a lid for closing the opening 48 of the back member 4. And at the time of imaging | photography, since a radiation is irradiated to the upper surface of the plane part 51, the said upper surface is a radiation entrance plane which concerns on this invention.

The housing 3 is integrated by joining the back member 4 and the front member 5 together. The joining method of the back member 4 and the front member 5 is not specifically limited, For example, you may join by screwing, and you may adhere and fix.
In addition, it is preferable that the height of the bending rising part 52 of the front member 5 and the height of the side wall part 42 of the back member 4 are substantially 1: 1.

  In the present embodiment, the thickness of the housing 3 in the radiation incident direction is 15 mm. Although the thickness dimension of the housing 3 in the radiation incident direction is not limited to 15 mm, it should be within the range of the JIS standard size (15 mm + 1 mm and 15 mm-2 mm) in a conventional screen / film cassette. Is preferred. Since most existing devices such as CR cassettes and Bucky tables are made to match the JIS standard size of this screen / film cassette, the cassette type can be obtained by adjusting the dimensions of the housing 3 to the JIS standard size. Even when photographing with the cassette type detector 1 which is the FPD, existing equipment can be used.

  The housing 3 is configured such that the bending rigidity (bending strength) in the vicinity of the ridgeline between the flat surface portion 51 and the bending rising portion 52 is higher than the central portion of the flat surface portion (rectangular portion) 51 of the front member 5. . That is, since the central part of the flat part (rectangular part) 51 has nothing to support, there is only the strength of the thickness of the flat part 51 of the front member 5, the force applied from the outside (patient) (patient weight), etc. In contrast, the vicinity of the ridge line of the flat portion 51 is supported by the bending rising portion 52 formed integrally with the flat portion 51, so that when the force is applied from the outside, it is bent and distorted. Is less likely to occur.

  Of the members constituting the housing 3, at least the front member 5 is formed of a material having a high radiation transmittance including carbon fiber or the like. The formation method is not particularly limited. For example, a carbon prepreg (material of a carbon plate) that is a sheet in which a carbon fiber is impregnated with a thermosetting resin such as an epoxy resin or an unsaturated polyester is molded into the shape of the front member 5. It is possible to obtain a desired shape by stacking on a mold and baking it at high temperature and pressure.

  In the present embodiment, the back member 4 is formed of a light metal such as aluminum or magnesium. In addition, the material which forms the back member 4 is not specifically limited, For example, it may be formed with the material containing a carbon fiber etc. similarly to the front member 5. FIG.

As shown in FIG. 2, back side cutout portions 43 a, 43 b, 43 c, and 43 d are provided on each of the four sides of the back member 4 from the side surface to the back surface. Among these back side cutout portions 43a to 43d, the back side cutout portions 43a and 43b are formed at both ends on the side orthogonal to the longitudinal direction of the front member 5, and the back side cutout portions 43c and 43d are the front member. 5 is formed at both ends on the side parallel to the longitudinal direction. And the front side notch part 53 is provided in the position corresponding to this back side notch part 43a, which is one end of the front member 5 on the side orthogonal to the longitudinal direction.
It is preferable that the width dimension of the back side notch parts 43a-43d and the front side notch part 53 is larger than the width dimension of the rechargeable battery 25 (refer FIG. 5 etc.) mentioned later. Further, the front side cutout 53 is cut out by 8 mm from the end of the front member 5 toward the center. In addition, although how much the front side notch part 53 is notched toward the center part from the edge part of the front member 5 is not specifically limited, It is preferable that it is 6 mm or more, More preferably, it is 8 mm or more.
In the present embodiment, when the back member 4 and the front member 5 are joined, the housing 3 has a take-out port 31a through which a rechargeable battery 25 described later can be taken in and out by the back-side notch 43a and the front-side notch 53. It is supposed to be formed.

  Further, the housing 3 includes a lid member 8 that is fitted into the take-out port 31, and the inside of the housing 3 becomes a sealed space by fitting the lid member 8 into the take-out port 31. In the present embodiment, the lid member 8 is formed of a nonconductive material such as a nonconductive plastic.

  3A is a plan view of the lid member 8 in FIG. 2 as viewed from the direction of arrow A, and FIG. 3B is a cross-sectional view taken along line BB in FIG. As shown in FIGS. 2 and 3B, the lid member 8 includes a side surface portion 81 and a lower surface portion 82 corresponding to the back side notch portion 43a, and an upper surface portion 83 corresponding to the front side notch portion 53. Therefore, it is substantially U-shaped in a side view according to the shape of the take-out port 31. Note that the shape of the lid member 8 is not limited to those illustrated here, and may be, for example, an L-shape. In this case, the shape of the front side notch and the back side notch is also a corresponding shape.

  As shown in FIG. 3 (a), guide convex portions 85, 85 are provided on the side end surfaces of the upper surface portion 83 and the lower surface portion 82 of the lid member 8, and the front side notch portion 53 and the back side cut portion are provided. As shown in FIG. 2, guide grooves 44 and 54 for guiding the guide convex portions 85 and 85 are provided in the notched portion 43a. The lid member 8 is configured to be fitted into the take-out port 31 by sliding the guide convex portions 85 and 85 along the guide grooves 44 and 54. In addition, the structure which takes out the cover member 8 in the taking-out port 31 is not limited to what was illustrated here. For example, the lid member can be opened and closed with respect to the take-out port by connecting the lower surface portion and the back member of the lid member or the upper surface portion and the front member via a hinge and rotating the lid member around the hinge axis. You may comprise so that it may become.

  In addition, an antenna device 9 is embedded in the side surface portion 81 of the lid member 8 for wirelessly transmitting and receiving information between the cassette type detector 1 and an external device.

As shown in FIGS. 2 and 3, the antenna device 9 is connected with a pair of flat radiation plates 91 and 92 made of metal and a pair of radiation plates 91 and 92, and the pair of radiation plates 91 and 92 is connected to the antenna device 9. A power feeding unit 93 that feeds power is provided.
In the present embodiment, of the pair of radiation plates 91 and 92, one radiation plate 91 is formed so that the shape in front view is a trapezoid, and the other radiation plate 92 has a substantially circular shape in front view. It is formed to become. The power feeding unit 93 is connected to the approximate center of the upper bottom portion of one radiation plate 91 and is connected to a part of the other radiation plate 92.
A predetermined gap is formed between the pair of radiation plates 91 and 92 by being connected by the power supply unit 93.

Note that the type and shape of the antenna device 9 are not limited to those illustrated here. Further, the antenna device 9 is not limited to the case where the antenna device 9 is embedded in the side surface portion 81 of the lid member 8, and may be attached to the outside or the inside of the lid member 8. However, if the antenna device 9 is provided at a position close to a conductive member made of a conductive material such as metal or carbon, the reception sensitivity is reduced. Therefore, the front member 5 made of a conductive material such as carbon or the like It is preferably provided at a position as far as possible from various electronic components 22 (see FIG. 5 and the like) formed of metal or the like, and preferably at least 6 mm or more.
In this regard, in the present embodiment, as described above, the front-side cutout 53 is cut out by 8 mm from the end of the front member 5 toward the center, and a lid formed of a non-conductive material here. The member 8 is fitted. For this reason, the antenna device 9 provided on the side surface portion 81 of the lid member 8 is disposed at a position 8 mm away from the front member 5 that is formed to include a conductive material such as carbon fiber. This is preferable for maintaining the reception gain.

  The housing 3 also includes a lid member 8a that is fitted into the back-side cutout portions 43b to 43d, and the inside of the housing 3 is sealed by fitting the lid member 8a into the back-side cutout portions 43b to 43d. It becomes space.

  4A is a plan view of the lid member 8a in FIG. 2 as viewed from the direction of the arrow A1, and FIG. 4B is a side view in FIG. 4A. As shown in FIGS. 2 and 4B, the lid member 8a includes a side surface portion 81a and a lower surface portion 82a corresponding to the back side cutout portions 43b to 43d, and the shape of the back side cutout portions 43b to 43d. The side view is almost L-shaped.

  As shown in FIGS. 4A and 4B, a guide convex portion 85a is provided on the side end surface of the lower surface portion 82a of the lid member 8a, and the back-side notches 43b to 43d are illustrated in FIG. As shown in FIG. 2, a guide groove 44a for guiding the guide convex portion 85a is provided. The lid member 8a is configured to be fitted into the back-side cutout portions 43b to 43d by sliding the guide convex portion 85a along the guide groove 44a. In addition, the structure which fits the cover member 8a in the back side notch parts 43b-43d is not limited to what was illustrated here. For example, the lower surface portion of the lid member and the back member are connected via a hinge, and the lid member can be opened and closed with respect to the back side cutout portions 43b to 43d by rotating the lid member around the hinge axis. You may comprise so that it may become.

  A rechargeable battery 25 (FIG. 5) provided inside the housing 3 on the same surface as the surface on which the back-side notch 43a is formed on the side surface of the back member 4, as shown in FIGS. A charging terminal 45 connected to an external power source or the like when charging the power source 46 is formed, and a power switch 46 for switching ON / OFF of the power source of the cassette type detector 1 is disposed. Further, a notch portion 55 into which the upper edge portion of the power switch is fitted is formed at one end of the bent rising portion 52 of the front member 5 and at a position corresponding to the power switch 46. Furthermore, the corner formed by the bent rising portion 52 and the flat portion 51 where the cutout portion 55 is formed is configured by, for example, an LED or the like to display the charging status of the rechargeable battery 25 and various operation statuses. An indicator 56 is provided.

  FIG. 5 is a plan view of the state in which the detector unit 2 is housed in the housing 3 as viewed from the lower side (the side opposite to the radiation incident side during imaging), and FIG. 6 is a cross-sectional view taken along the line CC in FIG. 7 is a sectional view taken along the line DD in FIG. 5, and FIG. 8 is a sectional view taken along the line EE in FIG. In FIG. 5, for convenience, the internal state of the housing 3 is shown without the bottom surface portion 41 of the back member 4.

  As shown in FIGS. 5 to 8, the detector unit 2 includes a detection panel 21, a circuit board 23 on which various electronic components 22 are mounted, and the like. In the present embodiment, the circuit board 23 is fixed to a base 24 made of resin or the like, and the circuit board 23 is attached via the base 24 by bonding and fixing the base 24 to the detection panel 21. It is fixed to the detection panel 21. The base 24 is not an essential component of the present invention, and the circuit board 23 or the like may be directly fixed to the detection panel 21 without the base 24 being interposed.

  As shown in FIG. 5, in this embodiment, the circuit board 23 on which the electronic component 22 is mounted is divided into four. The plurality of circuit boards 23 are dispersedly arranged so that the center of gravity positions of the plurality of circuit boards 23 as a whole are the center position G as viewed from the radiation incident surface side in the housing 3. Specifically, the plurality of circuit boards 23 are brought close to the respective corners of the detection panel 21 and arranged symmetrically with respect to the center position G, whereby the center of gravity of the entire plurality of circuit boards 23 is obtained. The position is the center position G. Note that the overall center-of-gravity position of the plurality of circuit boards 23 is not only the center-of-gravity position obtained based on the weight of only the plurality of circuit boards 23 but also the plurality of circuit boards 23 and each circuit board 23. The position of the center of gravity obtained based on the total weight of the electronic component 22 is also included.

  The electronic component 22 is disposed on the circuit board 23 along the outer periphery of the detection panel 21. The electronic component 22 is preferably disposed at a position as close to each corner of the detection panel 21 as possible. By arranging the electronic component 22 on the circuit board 23 in this way, when the detector unit 2 is housed in the housing 3, the electronic component 22 is near the corner of the housing 3 and the flat portion 51 (rectangular shape of the front member 5). Part).

  In the present embodiment, as the electronic component 22 arranged on the circuit board 23, for example, a central processing unit (CPU) (not shown) constituting a control unit 27 (see FIG. 13) that controls each unit, a ROM ( There are a storage unit (not shown) including a read only memory), a RAM (Random Access Memory), etc., a scanning drive circuit 16 (see FIG. 13), a signal readout circuit 17 (see FIG. 13), and the like. In addition to the ROM and RAM, an image storage unit that includes a rewritable read-only memory such as a flash memory or the like and that stores an image signal output from the detection panel 21 may be provided.

  The detector unit 2 is provided with a communication unit (not shown) that transmits and receives various signals to and from an external device. For example, the communication unit transfers the image signal output from the detection panel 21 to the external device via the antenna device 9 described above, or receives the imaging start signal transmitted from the external device via the antenna device 9. It is like that.

  Further, the cassette type detector 1 is configured on the base 24 at a position corresponding to the take-out port 31 and the back-side notches 43b to 43d when the detector unit 2 is housed in the housing 3. A plurality of driving units (for example, a scanning driving circuit 16 (see FIG. 13) described later, a signal reading circuit 17 (see FIG. 13), a communication unit (not shown), a storage unit (not shown), and a charge amount detection unit. (Not shown), indicator 56, detection panel 21 etc.) A plurality of rechargeable batteries 25 are provided as a power supply section for supplying power.

  As shown in FIG. 5, the plurality of rechargeable batteries 25 are arranged in a distributed manner such that the center of gravity positions of the plurality of rechargeable batteries 25 are the center position G viewed from the radiation incident surface side in the housing 3. Specifically, the plurality of rechargeable batteries 25 are arranged near the center of each side of the housing 3 and point-symmetrically with respect to the center position G, so that the center of gravity of the entire rechargeable batteries 25 is centered. It is in position G. The center of gravity position of the plurality of rechargeable batteries 25 is the position of the center of gravity obtained based on the weight of only the plurality of rechargeable batteries 23. The distributed arrangement means that the rechargeable batteries 25 are arranged at predetermined intervals in the housing 3, and at least the temperature at the highest temperature point in the housing 3 is suppressed to a temperature that does not cause thermal runaway. Thus, it is desirable that a plurality of rechargeable batteries 25 are dispersed.

  As the rechargeable battery 25, for example, a rechargeable battery such as a nickel cadmium battery, a nickel metal hydride battery, a lithium ion battery, a small sealed lead battery, or a lead storage battery can be used. Further, a fuel cell or the like may be applied instead of the rechargeable battery 25. Note that the shape, size, number, arrangement, and the like of the rechargeable battery 25 as the power supply unit are not limited to those illustrated in FIG.

  The plurality of rechargeable batteries 25 are arranged at predetermined positions on the base 24 so as to be electrically connected to the charging terminal 45 described above. For example, the cassette type detector 1 is connected to an external power source. So that the terminal on the charging device side and the charging terminal 45 on the housing 3 side are connected and the rechargeable battery 25 is charged. It has become.

  As shown in FIGS. 5, 7, and 8, a buffer member 26 is provided between the electronic components 22 and the rechargeable battery 25 to protect these components from being damaged by interference with the housing 3. Is provided. In addition, the number, arrangement | positioning, etc. of the buffer member 26 and the electronic component 22 are not limited to what was illustrated here. The material of the buffer member 26 is not particularly limited, and for example, an elastic resin such as polyurethane can be applied.

9 is a plan view of the detection panel 21, FIG. 10 is a side view of the detection panel 21 viewed from the direction of arrow F in FIG. 9, and FIG. It is sectional drawing.
The detection panel 21 includes a scintillator layer (light emitting layer) 211 that converts incident radiation into light, a first glass substrate 214 formed on one surface, and is laminated below the scintillator layer 211 and converted by the scintillator layer 211. The signal detector 151 (see FIG. 13) that detects the converted light and converts it into an electrical signal is configured to include a second glass substrate 213 formed on one surface, and these are laminated. It has a laminated structure.

  The scintillator layer 211 has, for example, a phosphor as a main component and outputs an electromagnetic wave having a wavelength of 300 nm to 800 nm, that is, an electromagnetic wave (light) ranging from ultraviolet light to infrared light centering on visible light, based on incident radiation. It is like that.

  The phosphor used in the scintillator layer 211 is, for example, a material using CaWO4 or the like as a base material, or a material in which a luminescent center substance is activated in a base material such as CsI: Tl, Cd2O2S: Tb, or ZnS: Ag. Can be used. Further, when the rare earth element is M, a phosphor represented by a general formula of (Gd, M, Eu) 2 O 3 can be used. In particular, CsI: Tl and Cd2O2S: Tb are preferable because of high radiation absorption and light emission efficiency. By using these, high-quality images with low noise can be obtained.

  The scintillator layer 211 is formed, for example, on a support (not shown) formed of various polymer materials (polymers) such as a cellulose acetate film, a polyester film, and a polyethylene terephthalate film by, for example, vapor deposition using a phosphor. The phosphor layer is formed of a columnar crystal of the phosphor. As the vapor deposition method, a vapor deposition method, a sputtering method, a chemical vapor deposition (CVD) method or the like is preferably used. In any of the methods, the phosphor layer can be vapor-grown into independent elongated columnar crystals on the support.

The scintillator layer 211 is affixed to the lower side of the first glass substrate 214 (the side opposite to the side on which radiation is incident during imaging), and the upper side of the first glass substrate 214 (the side on which radiation is incident during imaging). ) Is further laminated with a glass protective film 215.
In addition, a second glass substrate 213 is laminated below the scintillator layer 211 (on the side opposite to the side on which radiation is incident during imaging), and glass protection is provided below the second glass substrate 213. A film 216 is further laminated.

  Both the first glass substrate 214 and the second glass substrate 213 have a thickness of about 0.6 mm, and the end surfaces are cut by a laser, that is, the cut surfaces, the cut surfaces, and the glass substrates. Smoothing processing is performed to smooth the ridge line portion with the upper surface of the material and the ridge line portion between the cut surface and the lower surface of the glass substrate. In addition, the thickness of the 1st glass base material 214 and the 2nd glass base material 213 is not limited to 0.6 mm. Further, the first glass substrate 214 and the second glass substrate 213 may have different thicknesses.

Here, the smoothing process by cutting the end surfaces of the first glass substrate 214 and the second glass substrate 213 with a laser will be described.
When cutting glass, first, streaks (scratches) are formed on the glass surface to form vertical cracks in the thickness direction of the glass (scribing work), and stress is applied to break up the cracks. It is common to go through two work processes called (work). Conventionally, the work of scuffing the glass surface (scribing work) has been performed using cemented carbide, electrodeposited diamond, sintered diamond, or the like. However, when the glass surface is scratched with cemented carbide or diamond, fine irregularities are formed on the cut (divided) glass end face, and this irregularity part is applied when a load such as bending is applied to the glass. Since stress concentrates on the surface, there is a problem that it is easy to break.
In this regard, in the present embodiment, a work (scribing work) for scratching the surfaces of the first glass base material 214 and the second glass base material 213 using a laser is performed. When the laser is used in this way, the end face of the glass after cutting (dividing) is smoothed, so that the strength of the glass against a load such as bending can be increased.
Rather than the magnitude of external force, the glass substrate cracks are caused by the formation of partial burrs and partial convexities that cause stress concentration when cutting the glass substrate. Thus, by performing the process of smoothing the end face after cutting, it is possible to prevent the occurrence of cracking of the glass substrate even for a considerable external force (stress).

  As a cutting device for cutting the end surfaces of the first glass substrate 214 and the second glass substrate 213 with a laser, for example, in a laser oscillation unit, YAG (Yttrium Aluminum Garnet yttrium / aluminum / garnet crystal) is laser optical. A YAG laser or the like used as a medium is preferably used, but the cutting apparatus used for cutting is not limited to this.

  On the upper side of the second glass substrate 213 (side facing the scintillator layer 211), electromagnetic waves (light) output from the scintillator layer 211 are converted into electric energy and accumulated, and an image based on the accumulated electric energy. A signal detection unit 151 that is a detection unit that outputs a signal is formed.

As described above, in the present embodiment, the signal detection unit 151 is stacked on the lower side of the scintillator layer 211, and the second glass substrate 213 disposed on the lower side of the signal detection unit 151, and the scintillator layer The signal detection unit 151 and the scintillator layer 211 are sandwiched between the first glass substrate 214 disposed on the upper side of the 211 and the first glass substrate 214.
Conventionally, it was thought that cracking of the glass substrate could not be prevented unless the stress acting on the internal glass substrate through the housing was suppressed, so a space was provided between the housing and the glass substrate. A buffer member that relaxes / reduces the external force is frequently used. For this reason, the housing is further increased in size.
In this regard, the inventors of the present invention, rather than the size of the external force acting on the glass substrate, the partial burrs that cause stress concentration during the cutting of the glass substrate, It has been found that this is due to the formation of partial convex and concave portions. Therefore, in order to remove the burrs and the convex and concave portions that cause the stress concentration, a process of smoothing the end face after cutting is performed, and thereby the patient acting on the housing 3 having the above-described configuration is processed. It has become possible to prevent the occurrence of cracks and the like of the glass base materials 213 and 214 with respect to loads and deflections caused by weight and the like.

  In addition, a sealing member 217 is provided along the outer peripheral edge of the first glass base material 214 and the second glass base material 213, and the first glass base material 214 and the second glass base material 217 are provided by the sealing member 217. The glass substrate 213 is bonded and bonded. Thereby, intensity | strength can be raised more with respect to loads, such as a bending.

  Further, when the first glass substrate 214 and the second glass substrate 213 are bonded together, air is sucked from the space between the first glass substrate 214 and the second glass substrate 213. After the deaeration, the sealing member 217 is used for bonding and bonding. This prevents moisture contained in the air from affecting the scintillator layer 211 and the like. Long life can be achieved.

  Further, a buffer member 218 for protecting the detection panel 21 from an external impact or the like is provided near each corner of the detection panel 21 and between the corners.

  Here, the circuit configuration of the detection panel 21 will be described. FIG. 12 is an equivalent circuit diagram of a photoelectric conversion unit for one pixel constituting the signal detection unit 151.

As shown in FIG. 12, the configuration of the photoelectric conversion unit for one pixel is a photodiode 152 and a thin film transistor (hereinafter referred to as “TFT”) 153 that extracts electrical energy accumulated in the photodiode 152 as an electrical signal by switching. It consists of and. The photodiode 152 is an image sensor that generates and accumulates charges. The electrical signal taken out from the photodiode 152 is amplified by an amplifier 154 to a level that can be detected by the signal readout circuit 17.
Specifically, when light is irradiated, a charge is generated in the photodiode 152, and when a signal reading voltage is applied to the gate G of the TFT 153, the charge is transferred from the photodiode 152 connected to the source S of the TFT 153. It flows to the drain D side of the TFT 153 and is stored in a capacitor 154 a connected in parallel to the amplifier 154. The amplifier 154 outputs an electric signal amplified in proportion to the electric charge accumulated in the capacitor 154a.

  When the amplified electrical signal is output from the amplifier 154 and the electrical signal is extracted, the switch 154b connected in parallel to the amplifier 154 and the capacitor 154a is turned on, and the charge accumulated in the capacitor 154a is released. The amplifier 154 is reset. The photodiode 152 may simply be a photodiode having a regulation capacitance, or may include an additional capacitor in parallel so as to improve the dynamic range of the photodiode 152 and the photoelectric conversion unit.

  FIG. 13 is an equivalent circuit diagram in which such photoelectric conversion units are two-dimensionally arranged. Between the pixels, the scanning lines Ll and the signal lines Lr are arranged to be orthogonal to each other. One end side of the photodiode 152 is connected to the source S of the TFT 153, and the drain D of the TFT 153 is connected to the signal line Lr. On the other hand, the other end side of the photodiode 152 is connected to the other end side of the adjacent photodiode 152 arranged in each row, and is connected to a bias power source 155 through a common bias line Lb.

  The bias power source 155 is connected to the control unit 27 so that a voltage is applied to the photodiode 152 through the bias line Lb according to an instruction from the control unit 27. The gates G of the TFTs 153 arranged in each row are connected to a common scanning line Ll, and the scanning line Ll is connected to the control unit 27 via the scanning drive circuit 16. Similarly, the drain D of the TFT 153 arranged in each column is connected to a signal readout circuit 17 connected to a common signal line Lr and controlled by the control unit 27.

The signal readout circuit 17 is provided with the amplifier 154 for each signal line Lr described above. At the time of signal reading, a signal reading voltage is applied to the selected scanning line Ll, whereby a voltage is applied to the gate G of each TFT 153 connected to the scanning line Ll, and each photodiode is connected via each TFT 153. The charge generated in the photodiode 152 flows from the signal line 152 to each signal line Lr. Then, each amplifier 154 amplifies the charge for each photodiode 152, and information of the photodiode 152 for one row is extracted. This operation is performed for all the scanning lines Ll by switching the scanning lines Ll, whereby information is extracted from all the photodiodes 152.
A sample hold circuit 156 is connected to each amplifier 154. Each sample and hold circuit 156 is connected to an analog multiplexer 157 provided in the signal readout circuit 17, and the signal read out by the signal readout circuit 17 is described above from the analog multiplexer 157 via the A / D converter 158. It is output to the control unit 27.

  Note that the TFT 153 may be either an inorganic semiconductor type used in a liquid crystal display or the like, or an organic semiconductor type.

  Further, in the present embodiment, the case where the photodiode 152 as a photoelectric conversion element is used as the imaging element is illustrated, but a solid-state imaging element other than the photodiode may be used as the photoelectric conversion element.

  On the side of the signal detector 151, a scanning drive circuit 16 that sends a pulse to each photodiode (photoelectric conversion element) 152 to scan and drive each photodiode 152, and the electric power stored in each photoelectric conversion element A signal readout circuit 17 for reading out energy is arranged.

  Next, the operation of the cassette type detector 1 in the present embodiment will be described.

  In the present embodiment, first, a second glass substrate 213 having a signal detection unit 151 formed on one surface, and a first glass substrate 214 having a scintillator layer 211 attached to one surface are combined into a scintillator layer. 211 and the signal detection unit 151 are stacked so as to face each other, and after the space between the first glass substrate 214 and the second glass substrate 213 is deaerated, both of them are sealed by the sealing member 217. The glass substrates 213 and 214 are bonded and bonded. Next, the base 24 on which the circuit board 23 on which the various electronic components 22 are arranged and the rechargeable battery 25 are mounted at predetermined positions is placed on the first glass so that the side on which the circuit board 23 and the rechargeable battery 25 are mounted is down. Fix to the back side of the substrate 214. Thereby, the detector unit 2 is completed.

  Next, after the buffer member 26 is appropriately disposed at a location where the circuit board 23 and the rechargeable battery 25 are not disposed, the detector unit 2 is placed in the back member 4 so that the first glass base material 214 is on the upper side. Store in. Then, the power switch 46, the charging terminal 45, the indicator 56 provided on the side surface of the back member 4 and the respective electronic components 22 are electrically connected. Further, the front member 5 is joined to the back member 4, and the lid members 8 and 8a are taken out and fitted into the take-out port 31 and the back-side cutout portions 43b to 43d. Thereby, the antenna device 9 provided in the lid member 8 is electrically connected to the electronic component 22 of the detector unit 2.

  When the cassette-type detector 1 is used for imaging, for example, a patient to be imaged is laid on a bed, and the cassette-type detector 1 is placed on the side where the scintillator layer 211 is provided between the bed and the patient's body. The detector 1 is inserted and photographing is performed. Further, the cassette type detector 1 can be set and used on a Bucky table or the like used for photographing with an existing CR cassette.

  When the cassette-type detector 1 is transported, the user holds it as a whole, holds it by the side, or grasps it with his / her hand. Since the weight balance of the mold detector 1 is stable, it can be easily held without a handle.

As described above, according to the present embodiment, the plurality of rechargeable batteries 25 are dispersedly arranged so that the center of gravity of the plurality of rechargeable batteries 25 is the center position G viewed from the radiation incident surface side of the housing 3. Therefore, even when the user grasps and holds the housing 3 without a handle, the balance of the center of gravity is stable and can be easily carried. In particular, among the electronic component groups in the housing 3, the rechargeable battery 25 has a feeling of weight. Therefore, even if only the rechargeable batteries 25 are distributed, the weight balance can be stabilized.
Furthermore, in the present embodiment, since the plurality of circuit boards 23 are distributed so that the center of gravity of the entire plurality of circuit boards 23 becomes the center position G, as compared with the case where only the rechargeable batteries 25 are distributed. However, the balance of the center of gravity can be further stabilized.
And since the rechargeable battery 25 which is also a heat generating body is distributed, heat generation is dispersed, and the image quality and life can be improved.

  Moreover, although this embodiment demonstrated as an example the case where a rechargeable secondary battery (rechargeable battery 25) was used as a power supply part, a power supply part is not limited to a secondary battery. For example, a primary battery that requires battery replacement such as a manganese battery, a nickel / cadmium battery, a mercury battery, or a lead battery may be used.

  In the case of a six-cut size (8 inches × 10 inches) or a four-cut size (10 inches × 12 inches), the arrangement shown in the present embodiment may be used, but a half-cut size (14 inches × 17 inches) may be used. In that case, the position of the take-out port 31 into which the lid member 8 is fitted is preferably at each corner of the housing 3. If there is a cutout portion such as the outlet 31, the strength of the cutout portion is weakened, and the effect becomes more significant as the size of the cassette-type detector 1 increases. This is because it is necessary to arrange the take-out port 31 at the corner to prevent the strength from being lowered as much as possible. In this case, the rechargeable battery 25 is also arranged at a position corresponding to the lid member 8.

Further, in the present embodiment, the case where four circuit boards 23 and four rechargeable batteries 25 are installed is illustrated, but the number of installation is not limited to this, and if both are two or more, Good. Moreover, if the center of gravity position of the plurality of rechargeable batteries 25 and the circuit board 23 is the center position viewed from the radiation incident surface side of the housing 3, the layout of the plurality of rechargeable batteries 25 and the circuit board 23 has been described above. Of course, it is not limited to things. For example, as shown in FIG. 14, circuit boards 23a are arranged in parallel to the longitudinal direction at both ends in a direction orthogonal to the longitudinal direction of the housing 3A, and two rechargeable batteries 25a are distributed between the circuit boards 23a. As shown in FIG. 15, circuit boards 23b are arranged parallel to the longitudinal direction at both ends in the direction orthogonal to the longitudinal direction of the housing 3B, and four rechargeable batteries 25b are arranged between the circuit boards 23b. Can be arranged in such a manner that the positions of the center of gravity of the plurality of rechargeable batteries 25 and the circuit board 23 are aligned with the center position G of the housing 3.
Here, the center of gravity positions of the plurality of rechargeable batteries 25 and the circuit board 23 do not have to completely coincide with the center position G of the housing 3, and the user feels stable when holding the cassette type detector 1. As long as it feels within the range, it may deviate from the center position G.

  In addition, it is needless to say that the present invention is not limited to the above embodiment and can be modified as appropriate.

It is a perspective view which shows the cassette type detector which concerns on this embodiment. It is a disassembled perspective view of the housing in this embodiment. Fig.3 (a) is the front view which looked at the cover member from the arrow A direction in FIG. 2, FIG.3 (b) is BB sectional drawing of Fig.3 (a). 4A is a front view of the lid member as viewed from the direction of the arrow A1 in FIG. 2, and FIG. 4B is a side view of FIG. 4A. It is the schematic which shows the internal structure of the cassette type detector shown in FIG. It is CC sectional drawing of FIG. It is DD sectional drawing of FIG. It is EE sectional drawing of FIG. It is a top view which shows the detection panel in this embodiment. It is the side view which looked at the detection panel shown in FIG. 9 from the arrow F direction. It is GG sectional drawing of the detection panel shown in FIG. It is an equivalent circuit block diagram for 1 pixel of the photoelectric conversion part which comprises a signal detection part. FIG. 13 is an equivalent circuit configuration diagram in which the photoelectric conversion units illustrated in FIG. 12 are two-dimensionally arranged. It is the schematic which shows the other layout example of a rechargeable battery and a circuit board. It is the schematic which shows the other layout example of a rechargeable battery and a circuit board.

Explanation of symbols

1. Cassette type detector (Cassette type radiation image solid state detector)
2 Detector unit 3 Housing 4 Back member 5 Front member 8 Lid member 9 Antenna device 21 Detection panel 22 Electronic component 23 Circuit board 24 Base 25 Rechargeable battery 26 Buffer member 41 Bottom face part 42 Side wall part 51 Flat part 52 Bend rising part 151 Signal detector 211 Scintillator layer 213 Second glass substrate 214 First glass substrate 217 Sealing member G Center position

Claims (2)

A flat housing that is irradiated with radiation;
A detector unit built in the housing for converting the radiation incident through the housing into an electrical signal;
A plurality of rechargeable batteries built in the housing for supplying power to the detector unit;
The cassette type radiation image, wherein the plurality of rechargeable batteries are arranged in a distributed manner so that the center of gravity positions of the plurality of rechargeable batteries are substantially center positions as viewed from the radiation incident surface side of the housing. Solid state detector. The cassette-type radiation image solid detector according to claim 1,
The detector unit has a plurality of circuit boards on which electronic components for converting the radiation into electrical signals are mounted;
The cassette-type radiographic image, wherein the plurality of circuit boards are dispersedly arranged so that the center of gravity positions of the plurality of circuit boards as a whole are substantially center positions as viewed from the radiation incident surface side of the housing. Solid state detector.

Images