JP2010249722A - Radiation image detecting cassette - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent such a failure that a glass substrate which is glued and fixed cracks, even if expansion or contraction by heat occurs. <P>SOLUTION: The glass substrate 213 is stuck to a base 22 via an adhesive S while a void T is formed on part of a region between the glass substrate 213 and the base 22. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a radiological image detection cassette.

  In recent years, a digital radiographic image detection apparatus has been used as a method of obtaining a radiographic image by irradiating a subject with radiation and detecting the radiation transmitted through the subject. As such a radiation image detection apparatus, there is a so-called FPD (Flat Panel Detector).

  As an example of an FPD, a plurality of detection elements are two-dimensionally arranged on a substrate, radiation that has passed through a subject is irradiated onto a phosphor (scintillator), and visible light that is emitted according to the amount of irradiated radiation is charged. There is one that obtains a radiographic image by reading the electric charge accumulated in the photoelectric conversion element by converting into the photoelectric conversion element. Such an FPD has immediacy that a radiographic image can be obtained immediately after imaging.

  The electronic cassette for X-ray image recording described in Patent Document 1 is a portable FPD, and is carried to a predetermined place and used for radiographic imaging. In the electronic cassette for X-ray image recording described in Patent Document 1, the glass substrate that supports the two-dimensional photoelectric conversion element is bonded and fixed to a support plate, and is installed at a predetermined position in the electronic cassette for X-ray image recording. Has been.

Japanese Patent Laid-Open No. 2003-586

  In the electronic cassette for X-ray image recording described in Patent Document 1, when the glass substrate and the support plate are made of different materials, if the temperature rises in the electronic cassette for X-ray image recording due to the difference in thermal expansion coefficient, the glass substrate And the support plate will expand at different rates. If the glass substrate and the support plate are all bonded and fixed, and each expands at a different rate, the X-ray detection panel including the glass substrate is warped, or the bonded and fixed portion is peeled off and the glass substrate is displaced. I'm sorry. In some cases, the glass substrate is broken.

  Accordingly, an object of the present invention is to provide a radiation image detection cassette that prevents problems such as breakage of a glass substrate that is bonded and fixed even when expansion and contraction due to heat occurs.

In order to achieve the above object, a radiological image detection cassette according to the present invention comprises:
A portable radiation image detection cassette that detects radiation irradiated toward a subject and obtains radiation image data,
A detector that outputs an electrical signal corresponding to the incident radiation;
A glass substrate on which the detection unit is installed;
A base that supports the glass substrate;
The glass substrate and the base are bonded together with a gap formed in a partial region between the glass substrate and the base.

  According to the radiographic image detection cassette of the present invention, even when expansion and contraction due to heat occurs, it is possible to prevent a malfunction such as a broken glass substrate that is bonded and fixed, and continuously detect an appropriate radiographic image. I can do it.

It is a perspective view which shows a cassette type | mold detector. It is a disassembled perspective view of a housing. It is sectional drawing of the predetermined location which looked at the cassette type detector shown in FIG. 1 from the a direction. It is a perspective view which shows the joining method of the upper surface of a base, and a glass substrate. It is an expanded sectional view of a base and a glass substrate. It is a perspective view which shows another embodiment regarding the joining method of the upper surface of a base, and a glass substrate. It is a perspective view which shows another embodiment regarding the joining method of the upper surface of a base, and a glass substrate. It is explanatory drawing which shows another embodiment regarding the joining method of the upper surface of a base, and a glass substrate.

[Outline of cassette type detector]
FIG. 1 is a perspective view of a cassette type detector. A cassette type detector 1 which is a radiation image detection cassette is a cassette type flat panel detector. The cassette type detector 1 includes a radiation detection unit 2 (see FIG. 3 and the like) that detects irradiated radiation and acquires it as digital image data, and a housing 3 that houses the radiation detection unit 2 therein.

  In the present embodiment, the housing 3 is formed so that the thickness in the radiation incident direction is 15 mm. The thickness of the housing 3 in the radiation incident direction is preferably 16 mm or less, and has a size (15 mm + 1 mm and 15 mm-2 mm) in accordance with a standard (JIS Z 4905) standard for a screen / film cassette. It is preferable to be within the range (the international standard corresponding to JIS Z 4905 is IEC 60406).

  FIG. 2 is an exploded perspective view of the housing 3. As shown in FIG. 2, the housing 3 includes a hollow main body 31 having openings 311 and 312 at both ends, a first lid member 32 and a second lid 32 that close the openings 311 and 312 of the main body 31. And a lid member 33.

  The main body 31 is made of a carbon fiber body (for example, carbon fiber reinforced plastic: CFRP), and is lightweight and excellent in strength. The thickness of the main body 31 is cylindrical so that the strength of the cassette type detector 1 is maintained.

  The first lid member 32 and the second lid member 33 include lid body portions 321 and 331 and insertion portions 322 and 332, and are made of, for example, aluminum or magnesium.

  Engagement pieces 324 and 334 that engage the first lid member 32 and the second lid member 33 and the main body 31 are inserted into the openings 311 and 312 on the side surfaces of the insertion portions 322 and 332, respectively. Extends in the direction. Engagement projections 325 and 335 are provided on the outer surfaces of the engagement pieces 324 and 334, respectively. When the first lid member 32 and the second lid member 33 are inserted into the main body portion 31, the engagement convex portions 325 and 335 engage with the engagement concave portions 315 and 316 installed in the main body portion 31.

  A wireless communication unit 4 for wirelessly transmitting and receiving information between the cassette type detector 1 and an external device is embedded in one side surface of the lid main body 321 in the first lid member 32, and wirelessly The communication unit 4 is provided with a pair of flat radiation plates 41 and 42 made of metal and a power feeding unit 43 that supplies power to the pair of radiation plates 41 and 42.

  In addition, when charging the rechargeable battery 24 (see FIG. 3 and the like) provided inside the housing 3 on one surface of the lid main body 321 on the same surface as the surface on which the wireless communication unit 4 is formed. Further, a charging terminal 51 connected to an external power source and the like, and a power switch 52 for switching ON / OFF of the power source of the cassette type detector 1 are provided. Furthermore, the corner formed by the surface on which the wireless communication unit 4 is formed and the surface on the radiation incident side is composed of, for example, an LED or the like and displays an indicator for charging the rechargeable battery 24 and various operation states. 53 is provided.

[Internal structure of cassette type detector]
Next, the internal structure of the cassette type detector 1 will be described. FIG. 3 is a cross-sectional view of a predetermined portion of the cassette type detector 1 shown in FIG.

  As shown in FIG. 3, the radiation detection unit 2 includes a detector unit 21, a base 22, and electrical components (a relay board 23A, a control board 23B, a rechargeable battery 24 (for example, a lithium ion capacitor)). In the embodiment, the detector unit 21 is supported on the upper surface of the base 22, and a plurality of electrical components such as the control board 23 </ b> B and the rechargeable battery 24 are attached to the lower surface of the base 22. .

  The base 22 is flexible and is made of resin. The material of the base 22 is, for example, a resin in which polycarbonate and ABS are mixed. The base 22 supports the glass substrate 213, and although not shown in FIG. 3, a thin lead layer is interposed between the base 22 and the glass substrate 213.

  The detector unit 21 includes a scintillator 211, a detector 212, a glass substrate 213, a counter substrate 214, and the like. The basic structure of the detector unit 21 will be described. A detection unit 212 is installed on a glass substrate 213, and a scintillator 211 is installed thereabove. A counter substrate 214 is installed above the scintillator 211, and the scintillator 211 is sandwiched between the counter substrate 214 and the glass substrate 213. The glass substrate 213 and the counter substrate 214 are both substrates having a thickness of about 0.6 mm, for example.

  The scintillator 211 has a function of converting incident radiation into light. The scintillator 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 has become.

  The detection unit 212 converts the electromagnetic wave (light) output from the scintillator 211 into electric energy and accumulates it, and outputs an electric signal based on the accumulated electric energy. The electrical signal generated by the detection unit 212 is sent to the first relay board 23A by a flexible harness (not shown).

  A buffer material 215 is installed at the end of the base 22 and above the counter substrate 214.

  As described above, by using the cassette type detector 1 shown in FIGS. 1 to 3, it is possible to detect a radiographic image of a subject.

[Bonding of glass substrate and base]
Next, a method for joining the glass substrate 213 and the base 22 will be described in detail.

  FIG. 4 is a perspective view showing a method of joining the upper surface 22A of the base 22 and the glass substrate 213. As shown in FIG. In order to explain the method of joining the glass substrate 213 and the base 22, a part of the glass substrate 213 is omitted in FIG.

  The glass substrate 213 is bonded (adhered) to the upper surface 22A of the base 22 with an adhesive S (the hatched portion is a region where the adhesive S is applied). When the glass substrate 213 is bonded to the base 22 by the adhesive S, the glass substrate 213 is fixed at an appropriate position in the cassette type detector 1.

  As described above, the base 22 is made of resin and is made of a material different from that of the glass substrate 213. Therefore, since the thermal expansion coefficient of the base 22 and the thermal expansion coefficient of the glass substrate 213 are different, when the temperature rises in the cassette type detector 1, the base 22 expands and extends rather than the glass substrate 213.

  Considering this point, as shown in FIG. 4, on the upper surface 22 </ b> A of the base 22, the region X where the adhesive S is installed and the region Y where the adhesive S is not installed are alternately provided. In the longitudinal direction b of the glass substrate 213, the adhesive S is intermittently disposed.

  FIG. 5 is an enlarged cross-sectional view of the base 22 and the glass substrate 213. As shown also in FIG. 5, between the base 22 and the glass substrate 213, the area | region X in which the adhesive agent S is installed, and the area | region Y in which the adhesive agent S is not installed are provided alternately. . In the region Y, since the adhesive S is not installed, a gap T corresponding to the thickness of the adhesive S in the region X is formed (partial region between the base 22 and the glass substrate 213). In which a void T is formed).

  In the region X, the glass substrate 213 and the base 22 are joined by the adhesive S, but in the region Y, the glass substrate 213 and the base 22 are not joined. Therefore, even if the base 22 extends due to thermal expansion, the glass in the region Y The substrate 213 is not pulled in the left-right direction in FIG. As a result, the position of the glass substrate 213 due to the warp of the glass substrate 213 caused by the thermal expansion of the base 22 and peeling of the joined portion, rather than bonding with an adhesive in the entire area between the glass substrate 213 and the base 22. Problems such as displacement and cracking of the glass substrate 213 can be prevented.

  As described above, the glass substrate 213 is bonded to the glass substrate 213 by the adhesive by bonding the glass substrate 213 and the base 22 in a state where the gap T is formed in a partial region between the glass substrate 213 and the base 22. In addition to being fixed at an appropriate position, it is possible to prevent problems such as warpage, misalignment, and cracking of the glass substrate 213 caused by a difference in thermal expansion coefficient between the glass substrate 213 and the base 22. In particular, in the standard size cassette-type detector 1, since the glass substrate 213 and the base 22 are thin, warpage or the like is likely to occur due to the influence of thermal expansion. Therefore, the present invention is particularly effective in the standard size cassette type detector 1.

  Note that the longer direction b (see FIG. 4) of the glass substrate 213 is more susceptible to thermal expansion of the base 22 than the shorter direction. Therefore, it is preferable that the adhesive S is intermittently disposed in the longitudinal direction b of the glass substrate 213 as shown in FIG.

[Another embodiment (1) relating to joining of glass substrate and base]
FIG. 6 is an embodiment different from the embodiment shown in FIG. The embodiment shown in FIG. 6 is an embodiment in which the base 22 is formed of a fiber reinforced resin containing glass in order to increase the strength of the base 22 or to ensure the flatness of the base 22. It is.

  FIG. 6B shows the upper surface 22A of the base 22. For example, when the base 22 is formed by pouring a resin containing glass from the direction of the white arrow shown in FIG. 6B into the molding die, the fiber 22 made of glass is formed on the upper surface 22A of the base 22 as indicated by a broken line. Are oriented. As a result, in a direction (d direction) perpendicular to the fiber direction (c direction) of glass, a portion with a small amount of glass fiber (a plain portion in FIG. 6B) and a portion with a large amount of glass fiber and a small amount of resin. (The portion indicated by the broken line in FIG. 6 (b)) is the base 22 having a structure in which they are alternately arranged. When the temperature in the cassette-type detector 1 rises, the portion having a small amount of glass fiber and a large amount of resin is affected, and the base 22 tends to easily extend in the direction (d direction) perpendicular to the fiber direction of the glass.

  Therefore, in the embodiment of FIG. 6A, in the direction (d direction) orthogonal to the fiber direction of the glass, the region X where the adhesive S is installed and the region Y where the adhesive S is not installed are: The adhesives S are provided alternately and intermittently. By arranging the adhesive S in this way, the thermal expansion of the base 22 does not affect the glass substrate 213 in the direction in which the base 22 is easily stretched. Therefore, the glass substrate 213 is effectively warped, misaligned, or cracked. Etc. can be prevented.

[Another embodiment (2) regarding joining of glass substrate and base]
FIG. 7 shows an embodiment in which the base 22 is formed of fiber reinforced resin containing glass as in FIG.

  FIG. 7B shows the upper surface 22A of the base 22. For example, when the base 22 is formed by pouring a resin containing glass into a molding die by a pin gate, the base 22 is formed by flowing so that the resin spreads from a predetermined position as shown by an arrow in FIG. The And the fiber direction of the glass formed in the base 22 also becomes a shape along the direction where resin spreads.

  Therefore, in the embodiment of FIG. 7A, the adhesive S is disposed intermittently and in a matrix. With such an arrangement of the adhesive S, the thermal expansion of the base 22 does not affect the glass substrate 213 in any direction, so that the difference in thermal expansion coefficient between the glass substrate 213 and the base 22 can be effectively achieved. It is possible to prevent problems such as warpage, positional deviation, and cracking of the glass substrate 213 caused by the above.

[Another embodiment (3) regarding joining of glass substrate and base]
FIG. 8 shows yet another embodiment. As shown in FIG. 8, the glass substrate 213 and the base 22 are bonded with a flexible adhesive P. A plurality of gaps T are provided inside the adhesive P, and the gaps T are formed in a partial region between the glass substrate 213 and the base 22. As shown in FIG. 8, when a plurality of gaps T are formed inside the adhesive P, even if the base 22 extends due to thermal expansion, the gap T absorbs the extension of the base 22, and the base 22 However, the glass substrate 213 is not pulled in the left-right direction in FIG. Therefore, the embodiment shown in FIG. 8 can also prevent problems such as warpage, misalignment, and cracking of the glass substrate 213 caused by the difference in thermal expansion coefficient between the glass substrate 213 and the base 22.

DESCRIPTION OF SYMBOLS 1 Cassette type detector 2 Radiation detection part 3 Housing 21 Detector unit 22 Base 211 Scintillator 212 Detection part 213 Glass substrate 214 Opposite substrate

Claims (5)

A portable radiation image detection cassette that detects radiation irradiated toward a subject and obtains radiation image data,
A detector that outputs an electrical signal corresponding to the incident radiation;
A glass substrate on which the detection unit is installed;
A base that supports the glass substrate;
A radiation image detection cassette, wherein the glass substrate and the base are bonded together with a gap formed in a partial region between the glass substrate and the base.   The radiographic image detection cassette according to claim 1, wherein the gap is formed by intermittently disposing an adhesive between the glass substrate and the base.   The radiation image detection cassette according to claim 2, wherein an adhesive is intermittently disposed in the longitudinal direction of the glass substrate. The base is formed of a fiber reinforced resin,
The radiation image detection cassette according to claim 2, wherein an adhesive is intermittently disposed in a direction orthogonal to the fiber direction of the base.   The radiographic image detection cassette according to claim 2, wherein an adhesive is intermittently disposed in a matrix.

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