Testing device for evaluating performance of SPECT pixel detector

Abstract

The invention relates to a testing device for evaluating the performance of an SPECT pixel detector, and the testing device comprises a total housing, and a first fixing assembly, a second fixing assembly, a horizontal moving assembly and a radioactive source tank which are arranged in the total housing, the horizontal moving assembly comprises a motor, a lead screw and a track assembly, and the lead screw passes through a pedestal of the first fixing assembly. The first fixing assembly can move along the rail assembly, the second fixing assembly is arranged at the end, away from the motor, of the horizontal moving assembly, and the motor adjusts the distance between the two fixing assemblies through rotation of the lead screw. The radioactive source tank is provided with a rear cover and a front cover which are detachable, an inner cylinder is arranged in the radioactive source tank, and the radioactive source is fixed in the inner cylinder; the first fixing assembly clamps the radioactive source tank and can adjust the left-right position or the up-down position of the radioactive source tank. The second fixing assembly clamps the auxiliary block and can adjust the up-down position or the left-right position of the auxiliary block. The detector is installed in the auxiliary block and faces the front end of the radioactive source tank.

Description

Technical Field

[0001] The present invention belongs to the technical field of nuclear medicine imaging, and particularly relates to a test device for evaluating the performance of SPECT pixel detectors. Background Art

[0002] Single-photon emission computed tomography (SPECT) is a tomographic imaging technology for radioactive drugs (such as 99m Tc) that emit only a single γ photon per decay. Traditional SPECT detectors consist of a single large-area NaI crystal and optoelectronic devices. The pixel-type SPECT probe module is a new type of probe, usually based on an array of semiconductor radiation detectors or a combination of an array of scintillators and optoelectronic devices. In each array module, independent pixel detectors can directly perform radiation detection imaging. The pixel-type SPECT probe module is small in size, and multiple modules can be flexibly combined to form SPECT detectors of various field-of-view sizes, without being limited by the size of the large-area NaI crystal. At the same time, the pixel-type SPECT probe module has high sensitivity, better energy resolution, and single-photon events collected during detection do not affect other pixel regions, having good image performance.

[0003] Parameters such as the energy resolution, count rate consistency, sensitivity, image effect, and abnormal pixel ratio of each pixel are important parameters for measuring the performance of pixel-type SPECT probe modules. During the development and production of pixel-type SPECT probe modules, it is necessary to test and analyze and evaluate their above-mentioned performance. During testing, for detectors of different sizes, it is necessary to strictly control the distance between the radiation source and the center of the detector, and also ensure that the central axes of the radiation source and the detector are on the same horizontal line to ensure that the detector can be evenly irradiated by the radiation source and accurately reflect the response of the detector to the radiation source.

[0004] In addition, attention should also be paid to the radiation shielding and protection of the radiation source to prevent the radiation source used for testing from causing radiation hazards to the outside world and avoiding radiation exposure to the test personnel. At the same time, the detector is very sensitive to external light and external rays, and external light and external rays will cause unreliable test results and introduce noise. Therefore, it is also necessary to prevent interference from external light and rays to the detector. Summary of the Invention

[0005] In view of the above problems, the present invention provides a test device for evaluating the performance of SPECT pixel detectors, including a total housing and a first fixing component, a second fixing component, a horizontal moving component, and a radiation source can in the inner body of the total housing. The horizontal moving component includes a motor, a lead screw, and a track component. The lead screw passes through the base of the first fixing component, enabling the first fixing component to move along the track component. The second fixing component is provided at the end of the horizontal moving component away from the motor, and the motor rotates the lead screw to adjust the distance between the two fixing components;

[0006] The radiation source tank has a detachable rear cover and a front cover. An inner cylinder is provided inside the radiation source tank, and the radiation source is fixed inside the inner cylinder; the first fixing component clamps the radiation source tank and can adjust the left - right position or up - down position of the radiation source tank; the second fixing component clamps the auxiliary block and can adjust the up - down position or left - right position of the auxiliary block; the detector is installed inside the auxiliary block and faces the front end of the radiation source tank.

[0007] Optionally, the track assembly includes two ends, a track bottom plate and a track body. The track bottom plate is fixed on the bottom surface of the box body, and one end is provided at each end; one end covers a part of the motor close to the track assembly to protect the motor shaft and the coupling; the other end is used to support and fix the second fixing component;

[0008] A lead screw is provided between the track bottom plate and the track body. The track bottom plate, the track body and the lead screw are parallel to each other. One end of the lead screw passes through the end and is connected to the coupling, and the other end of the lead screw is rotatably connected to the other end; both ends of the track body are detachably connected to the two ends respectively. The track body is a flat cuboid and is suspended above the lead screw to assist in guiding the moving direction of the first fixing component.

[0009] Optionally, the first fixing component includes a first base, a first adjusting part and a fixing ring. A through - hole is provided at the bottom of the first base, and the lead screw passes through the through - hole; a hollow through - groove is provided in the middle of the first base, and the longitudinal section of the through - groove is square, and the track body passes through the through - groove; the top of the first base is connected to the first adjusting part, and a fixing ring is provided on the side of the first adjusting part facing the second fixing component, and the radiation source tank can be inserted into the fixing ring.

[0010] Further optionally, the fixing ring is a hollow cylinder, the central axis of the fixing ring is horizontally arranged, the radiation source tank can be inserted into the hollow space of the fixing ring, at this time the central axis of the radiation source tank is also horizontally arranged, and the front cover of the radiation source tank protrudes from the fixing ring, which is convenient for subsequent removal of the front cover.

[0011] Optionally, the radiation source tank is a hollow cylinder, which successively includes a rear cover, a tank body and a front cover. Both ends of the tank body are open, the front end of the rear cover is open and the rear end is closed, the front end of the front cover is closed and the rear end is open; an external thread is provided on the outer side of the rear part of the tank body, and an internal thread is provided on the inner wall of the front part of the rear cover, so that the rear cover can be screwed tightly on the rear part of the tank body; an external thread is provided on the outer side of the front part of the tank body, and an internal thread is provided on the inner wall of the front cover, so that the front cover can be screwed tightly on the front part of the tank body, so that the radiation source tank becomes a detachable closed body to prevent the rays of the radiation source from emitting.

[0012] Further optionally, the inner cylinder is a hollow frustum of a cone, with a smaller front end and a larger rear end. There is a circumferential clamping edge protruding outward on the outer side surface of the inner cylinder, and a circumferential secondary limiting edge protruding inward into the tank body is provided on the inner wall of the tank body. The secondary limiting edge is located between the limiting edge and the rear end of the tank body. When the inner cylinder is installed in the tank body, the clamping edge overlaps on the side surface of the secondary limiting edge facing the rear end of the tank body, further fixing the position of the inner cylinder in the tank body.

[0013] Further optionally, the radiation source is liquid. First, the cotton is stuffed into the inner cylinder from the rear end of the inner cylinder, and then the radiation source is dropped onto the cotton.

[0014] Optionally, the second fixing assembly includes a second adjusting part and a fixing groove. The second adjusting part is provided at the end of the track assembly away from the motor. The adjusting knob of the second adjusting part is on the side surface or the top surface of the second adjusting part, facilitating left - right adjustment or up - down adjustment of the fixing groove;

[0015] The fixing groove is provided on the side surface of the second adjusting part facing the first fixing assembly. At least one side surface of the fixing groove is provided with fastening screws for fixing the position of the auxiliary block.

[0016] Optionally, the auxiliary block is a cube, and there is a sunken receiving groove inside the auxiliary block for placing the detector. The receiving groove is a cube.

[0017] Further optionally, the top surface of the receiving groove is vacant, and the side surface of the receiving groove facing the first fixing assembly is also vacant; there is a detachable positioning plate above the receiving groove. After the detector is placed in the middle position of the receiving groove, the top surface of the detector protrudes from the top surface of the receiving groove. The middle part of the positioning plate is placed on the top of the detector, and both ends of the positioning plate are respectively connected to the screw holes on the top surfaces of the auxiliary blocks on both sides of the receiving groove through screws, thereby pressing and fixing the detector in the receiving groove with the positioning plate.

[0018] Optionally, the front end opening of the fixing ring faces the second fixing assembly, and a circular buckle cover is detachably provided at the front end opening. An infrared locator is provided on the side surface of the buckle cover facing the second fixing assembly, and the infrared locator is located at the center of the buckle cover. When the radiation source tank is not placed in the fixing ring, the buckle cover covers the front end opening of the fixing ring, and the infrared locator is at the center of the fixing ring, facilitating alignment of the fixing ring and the detector. The connection form between the buckle cover and the fixing ring can be a snap - type, and the infrared locator is a conventional infrared locator that can emit infrared rays with good linearity and horizontally. Description of the Drawings

[0019] Figure 1 It is a schematic structural diagram of a test device for SPECT pixel detector performance evaluation;

[0020] Figure 2 It is a schematic diagram of the horizontal moving assembly;

[0021] Figure 3 Schematic diagram of the horizontal moving component and two fixed components;

[0022] Figure 4 Schematic diagram of the first fixed component;

[0023] Figure 5 Schematic diagram of the second fixed component;

[0024] Figure 6 Schematic diagram of the radiation source tank and the inner cylinder;

[0025] Figure 7 Schematic diagram of the interior of the tank body;

[0026] Figure 8 Schematic diagram of the cap screwing device.

[0027] In the drawings, 1 - general housing, 2 - radiation source tank, 3 - motor, 4 - lead screw, 5 - rear cover, 6 - front cover, 7 - tank body, 8 - inner cylinder, 9 - auxiliary block, 10 - detector, 11 - end, 12 - track bottom plate, 13 - track body, 14 - first base, 15 - first adjusting part, 16 - fixing ring, 17 - limiting edge, 18 - secondary limiting edge, 19 - clamping edge, 20 - second adjusting part, 21 - fixing groove, 22 - fastening screw, 23 - receiving groove, 24 - positioning plate, 25 - clamping jaw, 26 - first controller, 27 - second base. Detailed implementation manners

[0028] This embodiment provides a test device for evaluating the performance of SPECT pixel detectors, as Figures 1-8 shown, including a general housing 1, a first fixed component, a second fixed component, a horizontal moving component and a radiation source tank 2 inside the general housing 1. The horizontal moving component includes a motor 3, a lead screw 4 and a track component. The lead screw 4 passes through the base of the first fixed component, enabling the first fixed component to move along the track component. The second fixed component is arranged at one end of the horizontal moving component far from the motor 3, and the motor 3 adjusts the distance between the two fixed components by rotating the lead screw 4;

[0029] The radiation source tank 2 has a detachable rear cover 5 and front cover 6. An inner cylinder 8 is provided inside the radiation source tank 2, and the radiation source is fixed inside the inner cylinder 8; the first fixed component clamps the radiation source tank 2 and can adjust the left - right position or up - down position of the radiation source tank 2; the second fixed component clamps the auxiliary block 9 and can adjust the up - down position or left - right position of the auxiliary block 9; the detector 10 is installed inside the auxiliary block 9 and faces the front end of the radiation source tank 2.

[0030] The second fixing component of the present invention is fixedly arranged. The first fixing component is slidably connected to the lead screw 4 and the track rod. By adjusting the horizontal position of the first fixing component through the motor 3, the distance between the first fixing component and the second fixing component can be changed, that is, the distance between the radiation source and the detector 10 can be changed. In the present invention, the liquid radiation source is fixed in the inner cylinder 8, and then the inner cylinder 8 is placed in the radiation source tank 2. The closed radiation source tank 2 can prevent the emission of rays. During the test, the total housing 1 is closed, and then the front cover 6 is opened. The rays irradiate towards the detector 10, and the test can be carried out. The detector 10 is fixed by the auxiliary block 9, and the auxiliary block 9 can hold and fix detectors 10 of different sizes. In the first fixing component and the second fixing component, one can adjust the up and down position, and the other can adjust the left and right position, that is, the alignment of the radiation source and the detector 10 is realized by using a relatively simple device.

[0031] Optionally, the total housing 1 is a cuboid, including a box body and a detachable upper cover. A handle is provided on the upper cover for facilitating the lifting of the upper cover. A through hole is provided on the side surface of the box body, and the power cord and data cable of the equipment inside the box body pass through the through hole and out of the box body.

[0032] The material of the total housing 1 is a material that can shield the rays of the radiation source, such as tungsten, lead or tungsten-lead alloy. When the upper cover is open, the radiation source tank 2 and the detector 10 can be installed, and their positions can be adjusted for alignment or calibration. When the total housing 1 is closed, it shields the internal rays, external light and external background rays, adjusts the distance between the radiation source and the detector 10 by using the motor 3, and tests the detector 10. During the test, the box body is placed flat on the horizontal table, and the bottom surface of the box body is kept horizontal.

[0033] Optionally, the track assembly includes two ends 11, a track bottom plate 12 and a track body 13. The track bottom plate 12 is fixed on the bottom surface of the box body, and one end 11 is provided at each end; one end covers a part of the motor 3 close to the track assembly to protect the rotating shaft and coupling of the motor 3; the other end is used to support and fix the second fixing component;

[0034] A lead screw 4 is provided between the track bottom plate 12 and the track body 13. The track bottom plate 12, the track body 13 and the lead screw 4 are parallel to each other. One end of the lead screw 4 penetrates into the end and is connected to the coupling, and the other end of the lead screw 4 is rotatably connected to the other end; both ends of the track body 13 are detachably connected to the two ends 11 respectively. The track body 13 is a flat cuboid and is suspended above the lead screw 4 to assist in guiding the moving direction of the first fixing component. Bearings are provided at both ends of the lead screw 4 to facilitate the connection of the two ends.

[0035] One end 11 covers the part of the motor 3 provided with the rotating shaft, and the main body part of the motor 3 is exposed outside this end to facilitate the heat dissipation of the motor 3. According to the conventional technology, the rotating shaft of the motor 3 is connected to the coupling, and then connected to one end of the lead screw 4 to facilitate driving the lead screw 4 to rotate.

[0036] Optionally, the first fixing component includes a first base 14, a first adjusting portion 15 and a fixing ring 16. A through hole is provided at the bottom of the first base 14, and the lead screw 4 passes through the through hole; a hollow through groove is provided in the middle of the first base 14, and the longitudinal section of the through groove is square, and the rail body 13 passes through the through groove; the top of the first base 14 is connected to the first adjusting portion 15, and a fixing ring 16 is provided on the side of the first adjusting portion 15 facing the second fixing component, and the radiation source canister 2 can be inserted into the fixing ring 16.

[0037] Further optionally, an internal thread is provided on the inner wall of the through hole, and the internal thread is adapted to the external thread on the outer surface of the lead screw 4, so that the first base 14 can be driven to move horizontally when the lead screw 4 rotates;

[0038] The internal dimension of the through groove is slightly larger than the outer dimension of the rail body 13, so that the rail body 13 can pass through the through groove. The first base 14 is slidably connected to the lead screw 4 and the rail body 13, and the rail body 13 can guide and limit the first fixing component to move along the length direction of the horizontal moving component, and the lead screw 4 and the rail body 13 play a dual guiding role.

[0039] Further optionally, the adjusting knob of the first adjusting portion 15 is located at the top or side of the first adjusting portion 15, which is convenient for adjusting the fixing ring 16 up and down or left and right.

[0040] Further optionally, the fixing ring 16 is a hollow cylinder, the central axis of the fixing ring 16 is horizontally arranged, the radiation source canister 2 can be inserted into the hollow space of the fixing ring 16, at this time the central axis of the radiation source canister 2 is also horizontally arranged, and the front cover 6 of the radiation source canister 2 protrudes from the fixing ring 16, which is convenient for removing the front cover 6 subsequently.

[0041] Optionally, the radiation source canister 2 is a hollow cylinder, which successively includes a rear cover 5, a can body 7 and a front cover 6. Both ends of the can body 7 are open, the front end of the rear cover 5 is open and the rear end is closed, and the front end of the front cover 6 is closed and the rear end is open; an external thread is provided on the outer side surface of the rear part of the can body 7, and an internal thread is provided on the inner wall of the front part of the rear cover 5, so that the rear cover 5 can be screwed tightly on the rear part of the can body 7; an external thread is provided on the outer side surface of the front part of the can body 7, and an internal thread is provided on the inner wall of the front cover 6, so that the front cover 6 can be screwed tightly on the front part of the can body 7, so that the radiation source canister 2 becomes a detachable closed body to prevent the rays of the radiation source from emitting.

[0042] Further optionally, a limiting edge 17 protruding towards the inside of the can body 7 is provided on the inner wall of the can body 7. There is an inclined wall surface between the limiting edge 17 and the front end of the can body 7. The inner diameter of the end of the wall surface connected to one end of the limiting edge 17 is smaller than the inner diameter of the end of the wall surface connected to the front end of the can body 7, so that the wall surface forms a horn shape with a large front and a small rear, so that the rays of the radiation source in the inner cylinder 8 can irradiate the detector according to the inclination angle of the wall surface during testing;

[0043] The inner diameter of the limiting edge 17 is smaller than the outer diameter of the front end of the inner cylinder 8, so that the limiting edge 17 can limit the position of the front end of the inner cylinder 8 and prevent the inner cylinder 8 from entering the area of the above-mentioned inclined wall surface.

[0044] Further optionally, the inner cylinder 8 is a hollow frustum of a cone, with a small front end and a large rear end. There is a circumferential protruding snap edge 19 on the outer side surface of the inner cylinder 8, and a circumferential secondary limiting edge 18 protruding towards the inside of the tank body 7 is provided on the inner wall of the tank body 7. The secondary limiting edge 18 is located between the limiting edge 17 and the rear end of the tank body 7. When the inner cylinder 8 is installed in the tank body 7, the snap edge 19 is lapped on the side surface of the secondary limiting edge 18 facing the rear end of the tank body 7 to further fix the position of the inner cylinder 8 in the tank body 7.

[0045] Further optionally, the radiation source is liquid. First, cotton is stuffed into the inner cylinder 8 from the rear end, then the radiation source is dropped onto the cotton, and then the inner cylinder 8 is inserted into the tank body 7 from the rear end of the tank body 7. The secondary limiting edge 18 catches the snap edge 19, and at the same time, the limiting edge 17 catches the front end of the inner cylinder 8. Then, the rear cover 5 is threadedly connected to the rear part of the tank body 7, and the rear end of the rear cover 5 abuts against the rear end of the inner cylinder 8 to fix the position of the inner cylinder 8. Finally, the front cover 6 is threadedly connected to the front part of the tank body 7 to close the radiation source tank 2. The above operations are carried out in a glove box that can shield rays.

[0046] The radiation source tank 2 is made of tungsten-nickel-iron or tungsten alloy material or other materials with ray shielding properties. The inner cylinder 8 can be made of hard transparent plastic.

[0047] Optionally, the second fixing component includes a second adjusting part 20 and a fixing groove 21. The second adjusting part 20 is arranged at the end of the track component far from the motor 3. The adjusting knob of the second adjusting part 20 is on the side or top of the second adjusting part 20, which is convenient for left-right adjustment or up-down adjustment of the fixing groove 21;

[0048] The fixing groove 21 is arranged on the side surface of the second adjusting part 20 facing the first fixing component. At least one side surface of the fixing groove 21 is provided with a fastening screw 22 for fixing the position of the auxiliary block 9.

[0049] Further optionally, the fixing groove 21 has a bottom surface and three vertical side surfaces connected in sequence. Among them, one side surface connected to the second adjusting part 20 is square, and there is a triangular side surface on each side of the square side surface. The areas of the two triangular side surfaces are equal, and the area of the triangular side surface gradually decreases from bottom to top, so that the fixing groove 21 forms an inner concave dustpan container similar to a horizontal triangular prism.

[0050] Further optionally, a fastening screw 22 penetrates through one triangular side of the fixing groove 21, and the screw head of the fastening screw 22 is located outside the fixing groove 21. When the auxiliary block 9 is placed in the fixing groove 21, the fastening screw 22 is screwed into the fixing groove 21 until the screw head of the fastening screw 22 abuts against one side of the auxiliary block 9, so that the opposite side of the auxiliary block 9 closely abuts against the other triangular side of the fixing groove 21, thereby fixing the position of the auxiliary block 9.

[0051] Optionally, the auxiliary block 9 is a cube, and a sunken receiving groove 23 is provided inside the auxiliary block 9 for placing the detector 10; the side of the auxiliary block 9 facing the first fixing assembly (this side is perpendicular to the two sides fixed by the side of the fixing groove 21 and the fastening screw 22) and the top surface of the auxiliary block 9 are respectively sunken into the auxiliary block 9 to form the receiving groove 23, and the receiving groove 23 is a cube.

[0052] Further optionally, the top surface of the receiving groove 23 is vacant, and the side of the receiving groove 23 facing the first fixing assembly is also vacant; a detachable positioning plate 24 is provided above the receiving groove 23. After the detector 10 is placed at the middle position in the receiving groove 23, the top surface of the detector 10 protrudes from the top surface of the receiving groove 23, the middle of the positioning plate 24 is placed on the top of the detector 10, and both ends of the positioning plate 24 are respectively connected to the screw holes on the top surfaces of the auxiliary block 9 on both sides of the receiving groove 23 through screws, thereby pressing and fixing the detector 10 in the receiving groove 23 with the positioning plate 24.

[0053] The detector 10 is a cube block with different sizes and small volume. If the detector 10 is directly placed in the fixing groove 21, the internal size of the fixing groove 21 is relatively large, and it is not easy to quickly locate the position of the detector 10. The fastening screw 22 directly acting on the detector 10 is also likely to squeeze or damage the detector 10. The present invention designs the auxiliary block 9, which has a low cost and is convenient for updating. First, the auxiliary block 9 is placed in the fixing groove 21 to occupy most of the volume in the fixing groove 21. The fastening screw 22 directly acts on the auxiliary block 9, and the auxiliary block 9 can be simply and quickly fixed. A receiving groove 23 is provided in the center of the top of the auxiliary block 9 for receiving the detector 10. The size of the receiving groove 23 is generally slightly larger than the largest detector 10, so that the vast majority of detectors 10 can be placed in the receiving groove 23. For a smaller detector 10, it can be placed at the middle position in the receiving groove 23 (which can be observed with the naked eye because the position of the detector 10 will be precisely adjusted by the first adjusting part 15 and the second adjusting part 20 later).

[0054] In use, place the middle part of the positioning plate 24 on the top surface of the detector 10. Insert screws through both ends of the positioning plate 24 and initially screw the screws at both ends into the corresponding screw holes on the top surface of the auxiliary block 9. Place the level on the upper surface of the positioning plate 24, and at the same time tighten the screws at both ends of the positioning plate 24. Observe with the level to ensure that the positioning plate 24 always remains horizontal. Until the positioning plate 24 firmly fixes the detector 10 in the receiving groove 23, and finally remove the level.

[0055] Optionally, a plurality of screw holes are provided on the outer side surface of the fixing ring 16. The plurality of screw holes are evenly distributed along the circumferential direction of the fixing ring 16 and are on the same vertical plane; the screw holes penetrate through the outer side surface of the fixing ring 16, communicating the external space of the fixing ring 16 with the internal hollow space. Screws are inserted into the screw holes, and the screw heads abut against the outer side surface of the radiation source can 2 in the hollow space to fix the radiation source can 2.

[0056] In use, face the rear cover 5 of the radiation source can 2 towards the first fixing component, insert the radiation source can 2 into the hollow space at the center of the fixing ring 16, and the front cover 6 of the radiation source can 2 protrudes from the front end of the fixing ring 16. For example, four screw holes are evenly provided on the side surface of the fixing ring 16, which are located at the four positions of the upper, lower, left, and right of the fixing ring 16. First, screw the lower screw into the lower screw hole in advance. When the screw is screwed into a predetermined depth, stop screwing and place the radiation source can 2; then screw the upper screw into the upper screw hole. When the screw is screwed into the same predetermined depth, at this time, the upper and lower screws respectively abut against the upper and lower surfaces of the radiation source can 2; then screw the two screws into the left and right screw holes respectively, and screw them into the same predetermined depth, so that the left and right screws respectively abut against the left and right surfaces of the radiation source can 2, thereby fixing the radiation source can 2 in four directions.

[0057] Optionally, the front end opening surface of the fixing ring 16 faces the second fixing component. A circular buckle cover is detachably provided at the front end opening. An infrared locator is provided on the side surface of the buckle cover facing the second fixing component. The infrared locator is provided at the center of the buckle cover. When the radiation source can 2 is not placed in the fixing ring 16, the buckle cover covers the front end opening of the fixing ring 16, and the infrared locator is at the center of the fixing ring 16, which is convenient for aligning the fixing ring 16 with the detector 10. The connection form between the buckle cover and the fixing ring 16 can be a snap type. The infrared locator is a conventional infrared locator that can emit linearly good and horizontal infrared rays.

[0058] When aiming, first, according to the above method, fix the detector 10 in the receiving groove 23 with the positioning plate 24, cover the fastening cover on the front opening of the fixing ring 16, turn on the infrared locator, and the infrared rays irradiate the sensing surface of the detector 10 opposite. For example, the first adjusting part 15 can adjust the up and down position of the fixing ring 16, and the second adjusting part 20 can adjust the left and right position of the detector 10. Through the combined adjustment of the two adjusting parts, the infrared rays irradiate the central position of the detector 10, that is, the center of the fixing ring 16 and the center of the detector 10 are on the same horizontal line. Both the first adjusting part 15 and the second adjusting part 20 are conventional one-way displacement regulators.

[0059] Then remove the fastening cover and the infrared locator, and install the radiation source tank 2 according to the above method. The center of the radiation source tank 2 can also be basically aligned with the center of the detector 10, so that the center of the radiation source can irradiate the middle position of the detector 10, and further enable the detector 10 to receive ray irradiation as evenly as possible.

[0060] Since the front cover 6 of the radiation source tank 2 needs to be rotated and unscrewed subsequently, and the rays will naturally emit after unscrewing. If the front cover 6 is unscrewed manually, the human hand may be irradiated by the rays. Therefore, it is necessary to cover the upper cover to close the total housing 1, and then unscrew the front cover 6. The total housing 1 can block the rays. The present invention designs a device that can unscrew the front cover 6.

[0061] Optionally, a cap unscrewing device is provided on the end 11 of the covering motor 3 of the track assembly. The cap unscrewing device includes a second base 27, a first controller 26, and a pair of clamping jaws 25. The second base 27 is arranged on the corresponding end 11, the first controller 26 is arranged on the second base 27, and the clamping jaws 25 are arranged on the side of the first controller 26 facing the first fixing assembly, which can control the pair of clamping jaws 25 to approach or move away from each other, and can also simultaneously control the clamping jaws 25 to rotate clockwise or counterclockwise. The first fixing assembly is located between the cap unscrewing device and the second fixing assembly.

[0062] Optionally, a second controller and a rotating seat are provided on the top of the first base 14. The top of the rotating seat is connected to the first adjusting part 15, and the second controller is connected to and controls the horizontal rotation of the rotating seat to drive the first adjusting part 15, the fixing ring 16, and the radiation source tank 2 to rotate.

[0063] After the radiation source tank 2 is aligned with the detector 10 (at this time, the cover and the infrared locator have been removed), the front cover 6 of the radiation source tank 2 faces the detector 10, and the overall housing 1 is closed. The second controller is an electromagnetic controller, which can control the rotating seat to rotate horizontally by 360°. The first adjusting part 15 together with the radiation source tank 2 is rotated by 180°, so that the front cover 6 of the radiation source tank 2 faces the jaws 25 of the cap screwing device. The first controller 26 is an electromagnetic controller, which controls a pair of jaws 25 to move away from each other and be in an open state. Then, the motor 3 drives the first base 14 towards the cap screwing device through the lead screw 4, so that the front cover 6 is moved between the pair of jaws 25. The first controller 26 controls the pair of jaws 25 to move closer to each other, thereby clamping the front cover 6. The first controller 26 then controls the jaws 25 to rotate to unscrew the front cover 6. While unscrewing, the motor 3 causes the first adjusting part 15 to move in a direction away from the cap screwing device in cooperation, so that the front cover 6 is separated from the body of the radiation source tank 2. The second controller then controls the rotating seat to rotate 180°, so that the front end of the tank body 7 faces the detector 10. At this time, the rays of the radiation source just hit the detector 10, and the detector 10 can start to be tested. During the test, the distance between the first fixing component and the second fixing component is adjusted for testing.

Claims

1. A test device for evaluating the performance of a SPECT pixel detector, characterized in that, A first fixing component, a second fixing component, a horizontal moving component and a radiation source tank including a general housing and an inner body within the general housing. The horizontal moving component includes a motor, a lead screw and a track component. The lead screw passes through the base of the first fixing component, enabling the first fixing component to move along the track component. The second fixing component is provided at the end of the horizontal moving component away from the motor, and the motor adjusts the distance between the two fixing components through the lead screw; The radiation source tank has a detachable rear cover and a front cover. An inner cylinder is provided inside the radiation source tank, and the radiation source is fixed inside the inner cylinder; The first fixing component clamps the radiation source tank and can adjust the left - right position or up - down position of the radiation source tank; The second fixing component clamps the auxiliary block and can adjust the up - down position or left - right position of the auxiliary block; The detector is installed inside the auxiliary block and faces the front end of the radiation source tank.

2. The test device according to claim 1, wherein The track component includes two ends, a track base plate and a track body. One end is provided at each end of the track base plate; One end covers a part of the motor close to the track component to protect the motor shaft and the coupling; The other end is used to support and fix the second fixing component; A lead screw is provided between the track base plate and the track body. The track base plate, the track body and the lead screw are parallel to each other. One end of the lead screw is connected to the coupling, and the other end of the lead screw is rotatably connected to the end close to the second fixing component; The two ends of the track body are respectively detachably connected to the two ends. The track body is a flat cuboid and is suspended above the lead screw to assist in guiding the moving direction of the first fixing component.

3. The test device according to claim 2, characterized in that, The first fixing component includes a first base, a first adjusting part and a fixing ring. A through - hole is provided at the bottom of the first base, and the lead screw passes through the through - hole; A hollow through - groove is provided in the middle of the first base, and the track body passes through the through - groove; The top of the first base is connected to the first adjusting part. A fixing ring is provided on the side of the first adjusting part facing the second fixing component, and the radiation source tank can be inserted into the fixing ring.

4. The test device according to claim 3, characterized in that, The fixing ring is a hollow cylinder, and the central axis of the fixing ring is horizontally arranged. The radiation source tank can be inserted into the hollow space of the fixing ring. At this time, the central axis of the radiation source tank is also horizontally arranged, and the front cover of the radiation source tank protrudes from the fixing ring, facilitating the subsequent removal of the front cover.

5. The testing device according to claim 1, wherein The radiation source tank is a hollow cylinder, successively including a rear cover, a tank body and a front cover. Both ends of the tank body are open. The front end of the rear cover is open and the rear end is closed. The front end of the front cover is closed and the rear end is open; External threads are provided on the outer side of the rear part of the tank body, and internal threads are provided on the inner wall of the front part of the rear cover, enabling the rear cover to be screwed tightly onto the rear part of the tank body; External threads are provided on the outer side of the tank body, and internal threads are provided on the inner wall of the rear part of the front cover, enabling the front cover to be screwed tightly onto the front part of the tank body, thereby making the radiation source tank a detachable closed body to prevent the rays of the radiation source from emitting.

6. The test device according to claim 1, characterized in that, The inner cylinder is a hollow frustum of a cone, with a small front end and a large rear end. A circumferential outward - protruding clamping edge is provided on the outer side of the inner cylinder, and a circumferential inward - protruding secondary limiting edge is provided on the inner wall of the tank body. The secondary limiting edge is between the limiting edge and the rear end of the tank body. When the inner cylinder is installed in the tank body, the clamping edge overlaps on the side of the secondary limiting edge facing the rear end of the tank body to fix the position of the inner cylinder in the tank body; The radiation source is liquid. The radiation source is dropped onto cotton, and then the cotton is stuffed into the inner cylinder from the rear end of the inner cylinder.

7. The testing device according to claim 2, wherein The second fixing component includes a second adjusting portion and a fixing groove. The second adjusting portion is provided at the end of the track component away from the motor; the fixing groove is provided on the side of the second adjusting portion facing the first fixing component, and fastening screws are provided on at least one side of the fixing groove for fixing the position of the auxiliary block. The auxiliary block is a cube, and a sunken receiving groove is provided inside the auxiliary block for placing the detector, and the receiving groove is a cube.

8. The testing device according to claim 7, wherein The top surface of the receiving groove is vacant, and the side surface of the receiving groove facing the first fixing component is also vacant; a detachable positioning plate is provided above the receiving groove. After the detector is placed at the middle position in the receiving groove, the top surface of the detector protrudes from the top surface of the receiving groove. The middle of the positioning plate is placed on the top of the detector, and both ends of the positioning plate are respectively connected to the screw holes on the top surfaces of the auxiliary blocks on both sides of the receiving groove through screws, so as to press and fix the detector in the receiving groove with the positioning plate.

9. The testing device according to claim 8, wherein, The front end opening of the fixing ring faces the second fixing component, and a circular buckle cover is detachably provided at the front end opening. An infrared locator is provided on the side surface of the buckle cover facing the second fixing component, and the infrared locator is provided at the center of the buckle cover. When the radiation source tank is not placed in the fixing ring, the buckle cover covers the front end opening of the fixing ring, and the infrared locator is at the center of the fixing ring, which is convenient for aligning the fixing ring with the detector.

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