Portable radiation detector

Abstract

To enhance the handleability of a portable radiation measuring unit by reducing the size and the weight of a portable radiation measuring unit.SOLUTION: An top end surface (14a) of a hollow probe (14) is formed to bend in a recessed pattern and a hollow rod-like holding part (16) is directly connected to a back end surface (14b) of the probe (14). A detection element (20) is provided on the top end surface (14a) side in the probe (14). The holding part (16) is formed to contain a wire cable (24) for connecting the detection element (20) and the circuit board (22) to each other.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] The present invention relates to a portable radiation measuring device for measuring radiation emitted from the thyroid gland of a subject. [Background technology]

[0002] When radioactive materials released into the environment due to nuclear or radiation accidents are ingested, the human body is exposed to internal radiation. In order to evaluate internal exposure to radiation due to the ingestion of radioactive iodine, a radioactive material, it is effective to measure the radiation emitted from the thyroid gland, where radioactive iodine easily accumulates. For this reason, portable radiation measuring devices have been developed that measure the radiation emitted from the thyroid gland of a subject (see Non-Patent Documents 1 and 2). The configuration of radiation measuring devices according to the prior art can be briefly explained as follows.

[0003] A radiation measuring device according to the prior art includes a square-pipe-shaped measuring body made of metal, with a handle on the top surface. A metal arm member is provided at the tip of the measuring body, and the arm member is configured to be rotatable and adjustable relative to the measuring body. A hollow probe is provided at the tip of the arm member, and the rear end of the probe is made of metal. The tip surface of the probe is capable of contacting the anterior surface of the subject's neck and is formed to be concavely curved.

[0004] The probe has a plurality of detecting elements at its distal end that detect radiation emitted from the subject's thyroid gland. The measuring device body has a circuit board that processes electrical signals output from the detecting elements. A plurality of wiring cables that connect the detecting elements to the circuit board are arranged between the arm member and the probe in an exposed state. [Prior art documents] [Non-patent literature]

[0005] [Non-Patent Document 1] Development of a new portable thyroid monitor using multiple GAGG detectors for infants after nuclear accidents. Retrieved: 2022 / 03 / 08 https: / / www.sciencedirect.com / science / article / pii / S1350448721001918 [Non-patent document 2] Development of a new hand-held type thyroid monitor using multipl GAGG detectors for young children following a nuclear accident Search date: 2022 / 03 / 08 https: / / www.nsr.go.jp / data / 000334921.pdf Summary of the Invention [Problem to be solved by the invention]

[0006] However, since the probe is attached to the tip of the measuring device body via an arm member, the portable radiation measuring device tends to be elongated in the length direction of the probe (a direction perpendicular to the width and thickness directions), which leads to an increase in size and weight of the portable radiation measuring device, resulting in a problem of reduced ease of handling of the portable radiation measuring device.

[0007] In particular, since multiple wiring cables are exposed to the outside between the arm member and the probe, when measuring radiation from the subject's thyroid gland, it is necessary to ensure that the wiring cables do not interfere with objects around the subject, which further reduces the ease of use of the portable radiation measuring device.

[0008] Therefore, one aspect of the present invention aims to reduce the size and weight of a portable radiation measuring device to improve the ease of handling of the portable radiation measuring device. [Means for solving the problem]

[0009] In order to solve the above-mentioned problems, one aspect of the present invention provides a portable radiation measuring device comprising: a hollow probe whose tip end surface is capable of contacting the anterior surface of a subject's neck and is formed to be concavely curved; a hollow rod-shaped handle portion directly connected to the rear end surface of the probe and whose interior is connected to the interior of the probe; a detection element provided inside the probe on the tip end surface side for detecting radiation emitted from the subject's thyroid gland; and a circuit board for processing electrical signals output from the detection element, wherein the handle portion is configured to accommodate a wiring cable connecting the detection element to the circuit board. [Effects of the Invention]

[0010] According to one aspect of the present invention, the portable radiation measuring device can be made smaller and lighter, thereby improving the ease of handling of the portable radiation measuring device. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a perspective view of a portable radiation measuring device according to an embodiment of the present invention. [Figure 2] FIG. 1 is a plan view of a portable radiation measuring device according to an embodiment of the present invention. [Figure 3] FIG. 2 is a bottom view of the portable radiation measuring device according to the present embodiment. [Figure 4] FIG. 2 is a right side view of the portable radiation measuring device according to the present embodiment. [Figure 5] FIG. 2 is a left side view of the portable radiation measuring device according to the present embodiment. [Figure 6] FIG. 1 is a front view of a portable radiation measuring device according to an embodiment of the present invention. [Figure 7] FIG. 2 is a rear view of the portable radiation measuring device according to the present embodiment. [Figure 8] 1 is a schematic diagram showing the inside of a portable radiation measuring device according to an embodiment of the present invention, with a cover member removed. FIG. [Figure 9] FIG. 9 is a cross-sectional view taken along line IX-IX in FIG. [Figure 10]FIG. 1 is a schematic diagram showing the height dimensions and curvature radius of the neck of standard anthropomorphic mathematical phantoms for infants and one-year-old children. [Figure 11] FIG. 1 is a schematic diagram showing the height dimensions and curvature radius of the neck of standard mathematical human phantoms for 5-year-old and 10-year-old children. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the specification and claims of this application, the "width direction" refers to the width direction of a portable radiation measurement device, a measurement device main body, or a probe. The "thickness direction" refers to the thickness direction of a portable radiation measurement device, a measurement device main body, or a probe. The "length direction" refers to the length direction of a portable radiation measurement device, a measurement device main body, or a probe, and is a direction perpendicular to the width direction and the thickness direction. In the drawings, "WD" refers to the width direction, "TD" refers to the thickness direction, "LD" refers to the length direction, "LDa" refers to the front end side or the front end direction, and "LDb" refers to the rear end side or the rear end direction.

[0013] The configuration of a portable radiation measuring device 10 according to this embodiment will be described with reference to FIGS. 1 to 11. FIG. 1 is a perspective view of the portable radiation measuring device 10 according to this embodiment. FIG. 2 is a plan view of the portable radiation measuring device 10 according to this embodiment. FIG. 3 is a bottom view of the portable radiation measuring device 10 according to this embodiment. FIG. 4 is a right side view of the portable radiation measuring device 10 according to this embodiment. FIG. 5 is a left side view of the portable radiation measuring device 10 according to this embodiment. FIG. 6 is a front view of the portable radiation measuring device 10 according to this embodiment. FIG. 7 is a rear view of the portable radiation measuring device 10 according to this embodiment. FIG. 8 is a schematic view showing the interior of the portable radiation measuring device 10 according to this embodiment, with the cover member 12a removed. FIG. 9 is a cross-sectional view taken along line IX-IX in FIG. 2. XA in FIG. 10 is a schematic view showing the height dimension and curvature radius of the neck of a standard mathematical anthropomorphic phantom of an infant. XB in Fig. 10 is a schematic diagram showing the height dimension and curvature radius of the neck of a standard mathematical anthropomorphic phantom for a one-year-old child. XIA in Fig. 11 is a schematic diagram showing the height dimension and curvature radius of the neck of a standard mathematical anthropomorphic phantom for a five-year-old child. XIB in Fig. 11 is a schematic diagram showing the height dimension and curvature radius of the neck of a standard mathematical anthropomorphic phantom for a ten-year-old child.

[0014] (Outline of portable radiation detector 10, detector body 12) As shown in FIG. 1 , a portable radiation measuring device 10 according to this embodiment is a measuring device that measures radiation emitted from the thyroid gland of a subject. The target of measurement by the portable radiation measuring device 10 is, for example, gamma rays, a type of radiation. The portable radiation measuring device 10 includes a hollow measuring device main body 12, which has a removable cover member 12a. The length of the measuring device main body 12 is set to be larger than the maximum width of the measuring device main body 12, and the length of the measuring device main body 12 is the longitudinal direction of the measuring device main body 12. Note that the length of the measuring device main body 12 may be set to be shorter than the maximum width of the measuring device main body 12.

[0015] (Probe 14, tip surface 14a) As shown in FIGS. 1 to 6, the measurement device main body 12 is equipped with a hollow probe 14, which is made of a synthetic resin such as polyethylene terephthalate or polyethylene. The distal end surface 14a of the probe 14 is capable of contacting the anterior surface of the subject's neck SC. The distal end surface 14a of the probe 14 is formed so as to be concavely curved toward the rear end surface 14b. Specifically, the distal end surface 14a of the probe 14 is formed in an arc shape, which is an example of a curved shape having a single radius of curvature. Note that instead of forming the distal end surface 14a of the probe 14 in an arc shape, it may be formed in a curved shape having multiple radii of curvature.

[0016] (rear end surface 14b, curved portion 14e) As shown in FIGS. 1 to 5 and 7 , the rear end surface 14b of the probe 14 is formed to be concavely curved along the tip surface 14a. Specifically, the rear end surface 14b of the probe 14 is formed in an arc shape, which is an example of a curved shape having a single radius of curvature, and the center of curvature of the rear end surface 14b of the probe 14 coincides with the center of curvature of the tip surface 14a of the probe 14. The radius of curvature of the rear end surface 14b of the probe 14 is larger than the radius of curvature of the tip surface 14a of the probe 14. Curved portions 14e having a radius of curvature smaller than the radius of curvature of the tip surface 14a of the probe 14 are formed on both sides of the rear end surface 14b of the probe 14 in the width direction. Note that instead of forming the rear end surface 14b of the probe 14 in an arc shape, it may be formed in a curved shape having multiple radii of curvature. The center of curvature of the rear end surface 14b of the probe 14 may be offset from the center of curvature of the tip surface 14a of the probe 14.

[0017] (Handle part 16) As shown in Figures 1 to 5, 8, and 9, the measuring device main body 12 has a hollow rod-shaped handle 16 that is directly connected to the center of the width direction of the rear end surface 14b of the probe 14. The interior of the handle 16 is in communication with the interior of the probe 14. Like the probe 14, the handle 16 is made of a synthetic resin such as polyethylene terephthalate or polyethylene. The cross-sectional outer shape of the handle 16 along its thickness direction is elliptical. However, instead of forming the cross-sectional shape of the handle 16 along its thickness direction into an ellipse, it may be formed into an oval or circular shape.

[0018] (Storage section 18) 1 to 8, the measuring device main body 12 has a hollow housing 18 directly connected to the base end of the handle 16, and the interior of the housing 18 is in communication with the interior of the handle 16. Like the probe 14 and the handle 16, the housing 18 is made of a synthetic resin such as polyethylene terephthalate or polyethylene.

[0019] (Shielding film 12c) 8, a shielding film 12c that blocks external electromagnetic waves is formed on the inner surface of the measuring device body 12 (the inner surface of the probe 14, the inner surface of the handle portion 16, and the inner surface of the housing portion 18). The shielding film 12c is made of, for example, conductive paint.

[0020] (Detection element 20) As shown in Fig. 8, a plurality of detecting elements 20 are provided on the distal end surface 14a side of the probe 14 to detect radiation emitted from the thyroid gland of the subject. Each detecting element 20 outputs an electrical signal corresponding to the amount of radiation. Each detecting element 20 has a scintillator such as a GAGG (gadolinium aluminum gallium garnet) scintillator, a CsI (cesium iodide) scintillator, a NaI (sodium iodide) scintillator, a BGO (bismuth germanium oxide) scintillator, a GSO (gadolinium silicon oxide) scintillator, a SrI (strontium iodide) scintillator, a LaBr3 (lanthanum bromide) scintillator, a CeBr3 (cerium bromide) scintillator, a LYSO (lutetium yttrium oxygen orthosilicate) scintillator, or an LSO (lutetium oxygen orthosilicate) scintillator. Each detection element 20 is shielded from external electromagnetic waves by a shielding film 12c, except for its detection surface.

[0021] (Circuit board 22, wiring cable 24) 8 and 9, a rigid circuit board 22 that processes electrical signals output from the multiple detection elements 20 is provided within the housing 18. In other words, the hollow housing 18 houses the rigid circuit board 22. The portable radiation measuring device 10 also includes multiple wiring cables 24 that connect the multiple detection elements 20 to the circuit board 22. The multiple wiring cables 24 are arranged from inside the probe 14 to inside the handle 16. In other words, the handle 16 is configured to house the multiple wiring cables 24.

[0022] The portable radiation measuring device 10 can be connected to an analysis device (not shown) such as a personal computer or tablet terminal via an external cable (not shown) such as a USB cable. The analysis device imports the wave height data output from the circuit board 22, analyzes it using dedicated software, and displays the analysis results. Power is supplied to the circuit board 22 by the analysis device via the external cable. Alternatively, power is supplied to the circuit board 22 by an external battery (not shown).

[0023] The circuit board 22 is not limited to a rigid type, but may be a flexible type. When the circuit board 22 is a flexible type, the circuit board 22 may be housed in the handle portion 16 or the probe 14.

[0024] (thickness dimension of probe 14) 1, 4, and 5, the thickness of probe 14 is set smaller than the height of a standard infant's neck. This is because if the thickness of probe 14 were equal to or greater than the height of a standard infant's neck, it would be difficult to bring tip surface 14a of probe 14 into contact with the front of the infant's neck. Furthermore, the thickness of probe 14 is set to be 0.8 times or more the height of a standard infant's neck. This is because if the thickness of the probe is less than 0.8 times the height of a standard infant's neck, the detection surface of each detection element 20 would be small, which could reduce the measurement accuracy of portable radiation measuring device 10.

[0025] In this embodiment, as shown in XA of FIG. 10 , the neck height dimension of a standard infant is the neck height dimension of a standard infant mathematical phantom, which is a computer-generated reproduction of the shape of a standard infant's body. As shown in XA of FIG. 10 , the neck height of the standard infant mathematical phantom (0-year-old) is 23.3 mm, and the radius of curvature of the neck of the standard infant mathematical phantom is 28.0 mm. As shown for reference in XB of FIG. 10 , the neck height of the standard one-year-old mathematical phantom is 34.8 mm, and the radius of curvature of the neck of the standard one-year-old mathematical phantom is 36.0 mm. As shown for reference in XIA of FIG. 11 , the neck height of the standard five-year-old mathematical phantom is 48.7 mm, and the radius of curvature of the neck of the standard five-year-old mathematical phantom is 38.0 mm. As shown in FIG. 11, XIB, for reference, the height of the neck of the standard mathematical anthropomorphic phantom for a 10-year-old child is 66.6 mm, and the radius of curvature of the neck of the standard mathematical anthropomorphic phantom for a 10-year-old child is 44.0 mm.

[0026] The height dimension of the neck of a standard infant is not limited to the height dimension of the neck of a standard mathematical anthropomorphic phantom of an infant, and height dimensions surveyed by public or private research organizations may also be used.

[0027] The thickness of probe 14 is set to be 0.5 times or less the radius of curvature of tip surface 14a of probe 14. This is because if the thickness of probe 14 exceeds 0.5 times the radius of curvature of tip surface 14a of probe 14, the thickness of probe 14 becomes too large, making it difficult to bring tip surface 14a of probe 14 into contact with the front of the infant's neck. Furthermore, the thickness of probe 14 is set to be 0.4 times or more the radius of curvature of tip surface 14a of probe 14. This is because if the thickness is less than 0.4 times the radius of curvature of tip surface 14a of probe 14, the detection surface of each detection element 20 becomes too small, which may reduce the measurement accuracy of portable radiation measurement device 10. Note that if tip surface 14a of probe 14 has multiple radii of curvature, the radius of curvature of tip surface 14a of probe 14 refers to the average value of the multiple radii of curvature.

[0028] (Thickness of handle 16, width of storage section 18) 4 and 5, the thickness of the handle 16 is set to be the same as the thickness of the probe 14. Furthermore, as shown in FIGS. 2 and 3, the width of the housing 18 is set to be larger than the width of the handle 16 and smaller than the width of the probe 14.

[0029] (Configuration regarding weight balance of portable radiation measuring device 10) 1 to 3, when a part of the handle 16 is used as a fulcrum, the housing 18 has a weight that corresponds to the weight acting on the probe 14. In other words, when a part of the handle 16 is used as a fulcrum, the weight acting on the housing 18 corresponds to the weight acting on the probe 14. In addition, when viewed in a plan view, the center of gravity of the portable radiation measuring device 10 is located on the handle 16. However, when viewed in a plan view, the center of gravity of the portable radiation measuring device 10 may be located at a position away from the handle 16.

[0030] (Action and effect) Next, the effects of this embodiment will be described.

[0031] In the configuration of the portable radiation measuring device 10, as described above, the handle 16 is directly connected to the center in the width direction of the rear end face of the probe 14. This prevents the portable radiation measuring device 10 from being extended in the longitudinal direction. As a result, according to this embodiment, the portable radiation measuring device 10 can be made smaller and lighter, improving the ease of handling of the portable radiation measuring device 10. In particular, because the probe 14, the handle 16, and the housing 18 are each made of synthetic resin, the portable radiation measuring device 10 can be made lighter than when the probe 14, etc. are made of metal.

[0032] As described above, the portable radiation measuring device 10 is configured such that the handle 16 accommodates the plurality of wiring cables 24. This prevents the plurality of wiring cables 24 from being exposed to the outside, and also prevents the plurality of wiring cables 24 from interfering with objects around the subject when measuring radiation from the subject's thyroid gland. This makes it possible to further improve the ease of use of the portable radiation measuring device 10 according to this embodiment.

[0033] In the configuration of the portable radiation measuring device 10, as described above, the thickness of the probe 14 is set to be smaller than the height of the neck of a typical infant. Furthermore, the thickness of the probe 14 is set to be 0.5 times or less the radius of curvature of the tip surface 14a of the probe 14. Therefore, the tip surface 14a of the probe 14 can be easily brought into contact with the front surface of the neck SC of infants and toddlers aged 5 or younger. This makes it possible to easily measure radiation emitted from the thyroid gland of infants and toddlers aged 5 or younger. In particular, as described above, the portable radiation measuring device 10 can be made smaller without the multiple wiring cables 24 being exposed to the outside, which significantly reduces the sense of pressure felt by the infant when measuring radiation emitted from the thyroid gland.

[0034] In the configuration of portable radiation measuring device 10, as described above, the thickness of probe 14 is set to be 0.8 times or more the height of the neck of a standard infant. The thickness of probe 14 is set to be 0.4 times or more the radius of curvature of tip surface 14a of probe 14. Therefore, according to this embodiment, the measurement accuracy of portable radiation measuring device 10 can be sufficiently ensured.

[0035] In the configuration of the portable radiation measuring device 10, as described above, the thickness of the handle 16 is set to be the same as the thickness of the probe 14. Therefore, when the tip surface 14a of the probe 14 is brought into contact with the front surface of the neck SC of the subject, the handle 16 does not come into contact with the area around the neck SC of the subject. As a result, according to this embodiment, it is possible to measure radiation from the thyroid gland of the subject without causing discomfort to the subject.

[0036] In the configuration of the portable radiation measuring device 10, the rear end surface 14b of the probe 14 is formed to be concavely curved along the front end surface 14a, making it easy for an operator to place their fingertip on the rear end surface 14b of the probe 14 while holding the handle in, for example, the first interdigital space. Furthermore, curved portions 14e are formed on both sides of the rear end surface 14b of the probe 14 in the width direction, making it easy for an operator to place their fingertip on the curved portion 14e of the probe 14. Furthermore, the width of the housing portion 18 is set to be larger than the width of the handle portion 16 but smaller than the width of the probe 14. This allows the weight of the portable radiation measuring device 10 to be balanced to some extent by the gravitational forces acting on the probe 14 and the housing portion 18. As a result, according to this embodiment, an operator can easily hold the portable radiation measuring device 10 in one hand, further improving the ease of handling of the portable radiation measuring device 10. In particular, since the cross-sectional shape along the thickness direction of the handle portion 16 is elliptical, oval, or circular, it is easier for the user to hold the handle portion 16 in one hand, thereby making the portable radiation measuring device 10 easier to handle.

[0037] In the configuration of portable radiation measuring device 10, as described above, when a portion of handle 16 is used as a fulcrum, housing 18 has a weight corresponding to the weight acting on probe 14. In a plan view, the center of gravity of portable radiation measuring device 10 is located on handle 16. This makes it easier to hold portable radiation measuring device 10 in one hand, improving the handling performance of portable radiation measuring device 10. As a result, according to this embodiment, an operator can hold an infant under the age of five as an examinee in one arm and one hand, and hold portable radiation measuring device 10 in the other hand to stably measure radiation from the infant's thyroid gland.

[0038] 〔summary〕 A portable radiation measuring device according to aspect 1 of the present invention comprises a hollow probe whose tip end surface is capable of contacting the front of the neck of a subject and is formed to be concavely curved; a hollow rod-shaped handle portion directly connected to the rear end surface of the probe and whose interior is connected to the interior of the probe; a detection element provided on the tip end surface side within the probe for detecting radiation emitted from the thyroid gland of the subject; and a circuit board for processing electrical signals output from the detection element, wherein the handle portion is configured to accommodate a wiring cable connecting the detection element to the circuit board.

[0039] According to the above configuration, since the handle is directly connected to the rear end surface of the probe, the portable radiation measuring device can be prevented from extending in the longitudinal direction of the probe, thereby making the portable radiation measuring device smaller and lighter, and improving the ease of handling of the portable radiation measuring device.

[0040] Since the handle is configured to accommodate the wiring cable, the wiring cable does not interfere with objects around the subject when measuring radiation from the subject's thyroid gland, thereby improving the ease of use of the portable radiation measuring device.

[0041] A portable radiation measuring device according to a second aspect of the present invention is the portable radiation measuring device of the first aspect, wherein the thickness of the probe is set to be smaller than the height of the neck of a standard infant.

[0042] According to the above configuration, the tip surface of the probe can be easily brought into contact with the front of the neck of infants and children under the age of five, and radiation emitted from the thyroid gland of infants and children under the age of five can be easily measured.

[0043] A portable radiation measuring device according to a third aspect of the present invention is the portable radiation measuring device according to the second aspect, wherein the thickness of the probe is set to be 0.8 times or more the height of the neck of a standard infant.

[0044] According to the above configuration, the measurement accuracy of the portable radiation measuring device can be sufficiently ensured.

[0045] In the portable radiation measuring device according to aspect 4 of the present invention, in aspect 2 or 3, the height dimension of the neck of the standard infant may be the height dimension of the neck of a standard human mathematical phantom, which is a computer reproduction of the body shape of a standard infant.

[0046] A portable radiation measuring instrument according to a fifth aspect of the present invention is the portable radiation measuring instrument of the first aspect, wherein the thickness of the probe may be set to 0.5 times or less the radius of curvature of the tip surface of the probe.

[0047] According to the above configuration, the tip surface of the probe can be easily brought into contact with the front of the neck of infants and children under the age of five, and radiation emitted from the thyroid gland of infants and children under the age of five can be easily measured.

[0048] A sixth aspect of the present invention relates to the portable radiation measuring instrument of the fifth aspect, wherein the thickness of the probe may be set to 0.4 times or more the radius of curvature of the tip surface of the probe.

[0049] According to the above configuration, the measurement accuracy of the portable radiation measuring device can be sufficiently ensured.

[0050] A portable radiation measuring instrument according to a seventh aspect of the present invention is the portable radiation measuring instrument of any one of the first to sixth aspects, wherein the rear end surface of the probe may be formed to be concavely curved along the front end surface.

[0051] According to the above configuration, an operator can easily place his / her fingertips on the rear end surface of the probe while pinching the handle between his / her fingers, which makes it easier for the operator to hold the portable radiation measurement device with one hand, thereby improving the ease of handling of the portable radiation measurement device.

[0052] A portable radiation measuring device according to aspect 8 of the present invention may be configured in such a way that, in the seventh aspect, curved portions having a radius of curvature smaller than the radius of curvature of the tip surface are formed on both sides of the width direction of the rear end surface of the probe.

[0053] According to the above configuration, the measurer can easily hang the probe on the curved portion side, which makes it easier for the measurer to hold the portable radiation measurement device in one hand, thereby further improving the ease of handling of the portable radiation measurement device.

[0054] A portable radiation measuring device according to a ninth aspect of the present invention is the portable radiation measuring device of any one of the first to eighth aspects, wherein the cross-sectional outer shape of the handle along the thickness direction may be elliptical, oval, or circular.

[0055] According to the above configuration, the user can easily hold the handle with one hand, and the handling of the portable radiation measurement device can be further improved.

[0056] A portable radiation measuring device according to a tenth aspect of the present invention is the portable radiation measuring device of any one of the first to ninth aspects, wherein the thickness of the handle portion may be set to be the same as the thickness of the probe.

[0057] According to the above configuration, when the tip of the probe is brought into contact with the front of the neck of the subject, the handle does not come into contact with the area around the neck of the subject, thereby making it possible to measure radiation from the thyroid gland of the subject without causing discomfort to the subject.

[0058] A portable radiation measuring device according to an eleventh aspect of the present invention is the portable radiation measuring device of any one of the first to tenth aspects, wherein the probe and the handle may each be made of synthetic resin.

[0059] According to the above configuration, the portable radiation measuring device can be made lighter in weight than when the probe and the like are made of metal.

[0060] A portable radiation measuring device according to aspect 12 of the present invention may be, in any of aspects 1 to 10, provided with a hollow storage section that is directly connected to the base end of the handle, the interior of which is connected to the interior of the handle, and that stores the circuit board, and the width dimension of the storage section may be set to be larger than the width dimension of the handle and smaller than the width dimension of the probe.

[0061] According to the above configuration, the weight of the portable radiation measuring device can be balanced to some extent by the gravity acting on the probe and the gravity acting on the housing, which makes it easier for a measurer to hold the portable radiation measuring device in one hand, thereby improving the ease of handling of the portable radiation measuring device.

[0062] A portable radiation measuring device according to aspect 13 of the present invention may be configured such that, in aspect 12, the housing section has a weight corresponding to the weight acting on the probe when a part of the handle section is used as a fulcrum.

[0063] According to the above configuration, the portable radiation measuring device can be easily held in one hand, improving the handling performance of the portable radiation measuring device, allowing an operator to hold an infant under five years old as an examinee in one arm and one hand, while holding the portable radiation measuring device in the other hand, and stably measure radiation from the infant's thyroid gland.

[0064] A portable radiation measuring device according to a fourteenth aspect of the present invention may be configured in such a way that, in a plan view, the center of gravity of the portable radiation measuring device in the thirteenth aspect is located on the handle.

[0065] According to the above configuration, the portable radiation measuring device can be easily held in one hand, improving the handling performance of the portable radiation measuring device, allowing an operator to hold an infant under five years old as an examinee in one arm and one hand, while holding the portable radiation measuring device in the other hand, and stably measure radiation from the infant's thyroid gland.

[0066] A portable radiation measuring device according to a fifteenth aspect of the present invention is the portable radiation measuring device of any one of the twelfth to fourteenth aspects, wherein the probe, the handle, and the housing may each be made of synthetic resin.

[0067] According to the above configuration, the portable radiation measuring device can be made lighter in weight than when the probe and the like are made of metal.

[0068] [Additional Notes] The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in the embodiments are also included in the technical scope of the present invention. Furthermore, new technical features can be formed by combining the technical means disclosed in the embodiments. [Explanation of symbols]

[0069] 10 Portable radiation detector 12 Measuring instrument body 12a Lid member 12c Shielding film 14 Probes 14a Tip surface 14b Rear end surface 14e Curved section 16 Handle 18 Storage section 20 Detector element 22 Circuit Board 24 Wiring cable

Claims

1. a hollow probe whose tip surface is capable of coming into contact with the anterior surface of the neck of the subject and is formed to be concavely curved; a hollow rod-shaped handle portion directly connected to the rear end surface of the probe and having an interior communicating with the interior of the probe; a detection element provided on the distal end surface side of the probe for detecting radiation emitted from the thyroid gland of the subject; a circuit board that processes the electrical signal output from the detection element. The portable radiation measuring device according to claim 1, wherein the handle is configured to accommodate a wiring cable that connects the detection element and the circuit board.

2. 2. The portable radiation measuring device according to claim 1, wherein the thickness of the probe is set smaller than the height of a standard infant's neck.

3. 3. The portable radiation measuring device according to claim 2, wherein the thickness of the probe is set to be 0.8 times or more the height of the neck of the standard infant.

4. 4. The portable radiation measuring device according to claim 2, wherein the height dimension of the neck of the standard infant is the height dimension of the neck of a standard infant mathematical phantom, which is a computer-generated reproduction of the body shape of a standard infant.

5. 2. The portable radiation measuring device according to claim 1, wherein the thickness of the probe is set to be 0.5 times or less the radius of curvature of the tip surface of the probe.

6. 6. The portable radiation measuring instrument according to claim 5, wherein the thickness of the probe is set to be 0.4 times or more the radius of curvature of the tip surface of the probe.

7. 7. The portable radiation measurement device according to claim 1, wherein the rear end surface of the probe is formed to be concavely curved along the tip end surface.

8. 8. The portable radiation measuring device according to claim 7, wherein curved portions having a radius of curvature smaller than the radius of curvature of the tip surface are formed on both sides in the width direction of the rear end surface of the probe.

9. 9. The portable radiation measuring device according to claim 1, wherein a cross-sectional outer shape of the handle taken along a thickness direction thereof is an ellipse, an oval, or a circle.

10. 10. The portable radiation measuring device according to claim 1, wherein the thickness of the handle is set to be the same as the thickness of the probe.

11. 11. The portable radiation measuring device according to claim 1, wherein the probe and the handle are each made of synthetic resin.

12. a hollow housing portion that is directly connected to the base end of the handle, the interior of which communicates with the interior of the handle, and that houses the circuit board; 12. The portable radiation measuring device according to claim 1, wherein a width of the housing portion is set to be larger than a width of the handle portion and smaller than a width of the probe.

13. 13. The portable radiation measuring device according to claim 12, wherein the housing has a weight corresponding to a weight acting on the probe when a part of the handle is used as a fulcrum.

14. 14. The portable radiation measurement device according to claim 13, wherein the center of gravity of the portable radiation measurement device is located on the handle portion when viewed from above.

15. 14. The portable radiation measuring device according to claim 12, wherein the probe, the handle, and the housing are each made of synthetic resin.

Images