Special-shaped LYSO: Ce image conversion screen and radiation imaging system and method based on special-shaped LYSO: Ce image conversion screen

Abstract

The invention relates to an LYSO: Ce image conversion screen, in particular to a special-shaped LYSO: Ce image conversion screen and a radiation imaging system and method based on the special-shaped LYSO: Ce image conversion screen, and aims to solve the problem that in the image diagnosis process of a specific radiation source with high center intensity and low surrounding intensity, the radiation imaging efficiency is high. The technical problem that a current radiation imaging system cannot obtain a high-quality radiation source center image and a high-quality surrounding image at the same time is solved. The special-shaped LYSO: Ce image conversion screen is provided with a peripheral part and a central part, the central part is located in the middle of the peripheral part; the back surface of the peripheral part and the back surface of the central part are located in the same plane, and the back surface of the peripheral part and the back surface of the central part jointly form a light emitting surface of the special-shaped LYSO: Ce image conversion screen; the thickness between the front surface and the back surface of the peripheral part is 1-10 mm, and the thickness between the front surface and the back surface of the central part is 1 / 5 of the thickness between the front surface and the back surface of the peripheral part.

Description

Technical Field

[0001] The present invention relates to a LYSO:Ce image conversion screen, in particular to a special-shaped LYSO:Ce image conversion screen and a radiation imaging system and method based thereon. Background Art

[0002] In the field of nuclear radiation imaging technology, especially in image diagnosis of radiation source performance, the working principle of the image measurement system based on the scintillator-type image conversion screen is as follows: the rays generated by the radiation source are irradiated onto the image conversion screen built into the radiation imaging system, and the fluorescence emitted by the image conversion screen is reflected by the reflector and focused by the lens onto the photocathode surface of the MCP image intensifier. After being multiplied and amplified by the MCP image intensifier, it is recorded by a high-speed CMOS camera and converted into a digital image.

[0003] The cerium-doped yttrium lutetium silicate (LYSO:Ce) image conversion screen in the current radiation imaging system is 20mm in length and width, and 5mm thick at all locations. It can be used for image diagnosis of uniform radiation sources with consistent ray intensity distribution. However, for a specific type of radiation source image diagnosis, that is, the radiation source intensity is not uniformly distributed, but has the characteristics of high central intensity and low peripheral intensity. The current radiation imaging system cannot simultaneously obtain high-quality images of the center and surrounding areas of the radiation source. This is mainly because the thickness of the currently configured image conversion screen is basically the same at all locations, and the ray intensity of the radiation source cannot be modulated, resulting in a limited dynamic range of the radiation imaging system. If the radiation source intensity distribution is inconsistent, with high central intensity and low peripheral intensity, the radiation source intensity is not uniformly distributed. Due to the characteristic of low surrounding intensity, the grayscale of the image acquired by the radiation imaging system is also distributed with strong center and weak surrounding. Limited by the dynamic range of the radiation imaging system, the image grayscale distribution range is 300~3000ADU, and is optimal in the range of 1000~2000ADU. If it is set to obtain a higher quality central image, that is, the grayscale of the central image is set to be optimal, the grayscale of the surrounding image is 170~340ADU, and the grayscale of the surrounding image is too low to identify effective features; if it is set to obtain a higher quality surrounding image, that is, the grayscale of the surrounding image is set to be optimal, the grayscale of the central image is 6000~12000ADU, the grayscale of the central image is oversaturated, and effective features cannot be identified. Summary of the Invention

[0004] The purpose of the present invention is to solve the technical problem that the current radiation imaging system cannot simultaneously obtain high-quality central and peripheral images of the radiation source during the image diagnosis process of a specific type of radiation source with high central intensity and low peripheral intensity, and to provide a special-shaped LYSO:Ce image conversion screen and a radiation imaging system and method based thereon.

[0005] To achieve the above object, the technical solution adopted by the present invention is:

[0006] A special-shaped LYSO:Ce image conversion screen, which is special in that:

[0007] having a peripheral portion and a central portion;

[0008] The central portion is located in the middle of the peripheral portion;

[0009] The back surface of the peripheral portion and the back surface of the central portion are located in the same plane, and the back surface of the peripheral portion and the back surface of the central portion together form a light emitting surface of the special-shaped LYSO:Ce image conversion screen;

[0010] The thickness between the front and back surfaces of the peripheral portion is 1 mm to 10 mm, and the thickness between the front and back surfaces of the central portion is 1 / 5 of the thickness between the front and back surfaces of the peripheral portion.

[0011] Furthermore, the front and peripheral surfaces of the special-shaped LYSO:Ce image conversion screen are both blackened.

[0012] Furthermore, the outer surfaces of the special-shaped LYSO:Ce image conversion screen are all polished surfaces with a roughness of less than 50 nm.

[0013] Further, the thickness between the front and back surfaces of the peripheral portion is 5 mm, and the thickness between the front and back surfaces of the central portion is 1 mm.

[0014] Furthermore, the shape of the peripheral portion is a rectangular parallelepiped, and the length and width of the peripheral portion are both 20 mm;

[0015] The shape of the front face of the central portion is an ellipse, the total length of the major axis of the ellipse is 10 mm, the total length of the minor axis of the ellipse is 9 mm, and the geometric center of the front face of the central portion coincides with the geometric center of the front face of the peripheral portion.

[0016] The present invention also provides a radiation imaging system based on a special-shaped LYSO:Ce image conversion screen, which is special in that:

[0017] It includes a metal dark box and a reflector, an optical lens, an MCP image intensifier, a CMOS camera and the above-mentioned special-shaped LYSO:Ce image conversion screen arranged in the metal dark box;

[0018] The metal dark box is provided with an incident port for the focal spot image of the radiation emitted by the radiation source to pass through;

[0019] The special-shaped LYSO:Ce image conversion screen is set at a position close to the entrance and the radiation source, and is used to receive the focal spot image of the radiation emitted by the radiation source and convert it into a visible light focal spot image before emitting it;

[0020] The reflector is arranged in the emission direction of the special-shaped LYSO:Ce image conversion screen and is used to reflect the visible light focal spot image emitted from the light-emitting surface of the special-shaped LYSO:Ce image conversion screen;

[0021] The optical lens, MCP image intensifier and CMOS camera are arranged in sequence on the reflective light path of the reflector; the optical lens is used to focus the visible light focal spot image reflected by the reflector and then image it to the MCP image intensifier; the MCP image intensifier is used to multiply and amplify the received image and then image it to the CMOS camera; and the CMOS camera is used to record the final image.

[0022] Furthermore, the reflecting surface of the reflector forms an angle of 45° with the optical axis of the special-shaped LYSO:Ce image conversion screen; and the optical lens is a zoom lens with an adjustable focal length within the range of 70 mm to 200 mm.

[0023] Furthermore, the diameters of the photocathode and phosphor screen of the MCP image intensifier are both 25 mm, the photocathode material is S20 multi-alkali photocathode, the phosphor screen type is P20, the static spatial resolution of the MCP image intensifier is greater than 50 lp / mm, and the gain voltage of the MCP image intensifier is adjustable within 0 to 5 V.

[0024] Furthermore, the chip of the CMOS camera is coupled to the fluorescent screen of the MCP image intensifier through a light cone, and the fluorescent screen image of the MCP image intensifier is imaged onto the chip of the CMOS camera. The pixel array of the CMOS camera is B×C, where the value range of B is 1280 to 2048 and the value range of C is 1024 to 2048.

[0025] The present invention further provides a radiation imaging method based on a special-shaped LYSO:Ce image conversion screen, which is special in that it includes the following steps:

[0026] S1. Build the above-mentioned radiation imaging system based on the special-shaped LYSO:Ce image conversion screen, and set the entrance of the metal dark box toward the radiation source with high intensity in the center and low intensity in the periphery;

[0027] S2. The high-intensity radiation generated at the center of the radiation source is irradiated onto the central portion of the special-shaped LYSO:Ce image conversion screen, and the low-intensity radiation generated around the radiation source is irradiated onto the peripheral portion of the special-shaped LYSO:Ce image conversion screen;

[0028] S3, adjusting the optical lens so that the visible light focal spot image emitted from the special-shaped LYSO:Ce image conversion screen and reflected by the reflector is focused by the optical lens and then imaged onto the photocathode of the MCP image intensifier;

[0029] S4, adjusting the MCP image intensifier so that the MCP image intensifier multiplies and amplifies the received image and then images it into the CMOS camera;

[0030] S5. The final image is recorded by a CMOS camera, completing the radiation imaging based on the special-shaped LYSO:Ce image conversion screen.

[0031] Compared with the prior art, the present invention has the following beneficial technical effects:

[0032] 1. The special-shaped LYSO:Ce image conversion screen of the present invention and the radiation imaging system and method based thereon are configured to reduce the grayscale of the central image of the radiation image by setting the thickness of the peripheral portion of the special-shaped LYSO:Ce image conversion screen to 5 mm and the thickness of the central portion to 1 mm, where the thickness of the central portion is 1 / 5 of the thickness of the peripheral portion. When the LYSO:Ce image conversion screen is 1 mm thick, the grayscale of the radiation image is 1 / 6 of that when the thickness is 5 mm. Therefore, during the image diagnosis process of a type of radiation source having high central intensity and low peripheral intensity, when the grayscale of the peripheral image is set to optimal, the grayscale of the central image is between 1000 and 2000 ADU, which is also within the optimal grayscale range. This achieves the purpose of achieving consistent grayscale between the central image and the peripheral image during the image diagnosis process of a type of radiation source having higher central intensity than peripheral intensity.

[0033] 2. The special-shaped LYSO:Ce image conversion screen of the present invention can improve the imaging quality of the special-shaped LYSO:Ce image conversion screen by providing a blackening treatment on the front and peripheral surfaces of the special-shaped LYSO:Ce image conversion screen;

[0034] 3. The special-shaped LYSO:Ce image conversion screen of the present invention has a better imaging effect by setting the outer surface of the special-shaped LYSO:Ce image conversion screen to be a polished surface with a roughness of less than 50nm. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a front schematic diagram of an embodiment of a special-shaped LYSO:Ce image conversion screen of the present invention;

[0036] Figure 2 A schematic diagram of an embodiment of a radiation imaging system based on a special-shaped LYSO:Ce image conversion screen according to the present invention;

[0037] Figure 3 This is the gamma ray irradiation imaging result of a cobalt source in an embodiment of the radiation imaging system based on a special-shaped LYSO:Ce image conversion screen of the present invention.

[0038] The following are the descriptions of the reference numerals:

[0039] 1-special-shaped LYSO:Ce image conversion screen, 11-peripheral part, 12-central part, 2-reflecting mirror, 3-optical lens, 4-MCP image intensifier, 5-CMOS camera, 6-metal darkroom. DETAILED DESCRIPTION

[0040] To make the objects, advantages and features of the present invention more clear, the following describes in further detail a special-shaped LYSO:Ce image conversion screen and a radiation imaging system and method based thereon proposed by the present invention in conjunction with the accompanying drawings and specific embodiments.

[0041] refer to Figure 1 and Figure 2 The present invention provides a radiation imaging system based on a special-shaped LYSO:Ce image conversion screen, which is suitable for image measurement of the two-dimensional intensity distribution of a radiation source. The system includes a special-shaped LYSO:Ce image conversion screen 1, a reflector 2, an optical lens 3, an MCP image intensifier 4, a CMOS camera 5 and a metal dark box 6. The special-shaped LYSO:Ce image conversion screen 1, the reflector 2, the optical lens 3, the MCP image intensifier 4 and the CMOS camera 5 are all arranged inside the metal dark box 6. The metal dark box 6 is provided with an incident port for the focal spot image of the rays emitted by the radiation source to pass through.

[0042] like Figure 2 As shown, the special-shaped LYSO:Ce image conversion screen 1 is set in the metal dark box 6 near the entrance and close to the radiation source, and is used to receive the radiation focal spot image emitted by the radiation source and convert it into a visible light focal spot image before emitting it. Figure 1As shown, the special-shaped LYSO:Ce image conversion screen 1 has a peripheral part 11 and a central part 12, the central part 12 is located in the middle of the peripheral part 11, the back of the peripheral part 11 and the back of the central part 12 are located in the same plane, and the back of the peripheral part 11 and the back of the central part 12 together form the light-emitting surface of the special-shaped LYSO:Ce image conversion screen 1, the peripheral part 11 is in the shape of a rectangular parallelepiped, the thickness between the front and back of the peripheral part 11 is 5 mm, the length and width of the peripheral part 11 are both 20 mm, the thickness between the front and back of the central part 12 is 1 / 5 of the thickness between the front and back of the peripheral part 11, the thickness between the front and back of the central part 12 is 1 mm, the shape of the front of the central part 12 is elliptical, the total length of the major axis of the ellipse is 10 mm, the total length of the minor axis of the ellipse is 9 mm, and the geometric center of the front of the central part 12 coincides with the geometric center of the front of the peripheral part 11. Based on a comprehensive evaluation, the thickness between the front and back sides of the peripheral portion 11 is set to 5 mm, which not only enables the special-shaped LYSO:Ce image conversion screen 1 to have a better imaging effect, but also enables the special-shaped LYSO:Ce image conversion screen 1 to have a higher detection efficiency; the outer surfaces of the special-shaped LYSO:Ce image conversion screen 1 are all polished surfaces with a roughness of less than 50 nm, so this setting can enable the special-shaped LYSO:Ce image conversion screen 1 to have a better imaging effect; the front and outer peripheral surfaces of the special-shaped LYSO:Ce image conversion screen 1 are both blackened, which can make the imaging quality of the special-shaped LYSO:Ce image conversion screen 1 higher.

[0043] In other embodiments, the thickness between the front and back of the central part 12 is 1 / 5 of the thickness between the front and back of the peripheral part 11. In order to ensure the imaging effect, the thickness between the front and back of the peripheral part 11 can also be set to 1mm, 2mm, 3.5mm, 4.5mm, 5.5mm, 7.5mm, 9mm, 10mm, etc.; the shape and size of the front of the central part 12 and the shape and size of the front of the peripheral part 11 can be set according to the situation of the radiation source.

[0044] like Figure 2 As shown, the reflector 2 is arranged in the emission direction of the special-shaped LYSO:Ce image conversion screen 1, and the reflective surface of the reflector 2 forms a 45° angle with the optical axis of the special-shaped LYSO:Ce image conversion screen 1. The reflector 2 is used to reflect the visible light focal spot image emitted from the light-emitting surface of the special-shaped LYSO:Ce image conversion screen 1 to prevent the rays from damaging the MCP image intensifier 4 and the CMOS camera 5 after passing through the special-shaped LYSO:Ce image conversion screen 1.

[0045] like Figure 2As shown, the optical lens 3, MCP image intensifier 4, and CMOS camera 5 are sequentially arranged in the reflected light path of reflector 2. Optical lens 3 is a zoom lens with an adjustable focal length within the range of 70mm to 200mm. It is used to focus the focal spot image of visible light reflected by reflector 2 and image it onto the photocathode of MCP image intensifier 4. The photocathode and phosphor screen of MCP image intensifier 4 both have a diameter of 25mm. The photocathode material is an S20 multi-alkali photocathode, and the phosphor screen type is P20. The static spatial resolution of MCP image intensifier 4 is greater than 50 lp / mm. The gain coefficient of MCP image intensifier 4 can be set by adjusting the gain voltage, which is adjustable within the range of 0 to 5V. MCP image intensifier 4 is used to amplify the received image and image it onto CMOS camera 5. The chip of the CMOS camera 5 is coupled to the fluorescent screen of the MCP image intensifier 4 through a light cone, and the fluorescent screen image of the MCP image intensifier 4 is imaged onto the chip of the CMOS camera 5. The pixel array of the CMOS camera 5 is 1280×1024 and 12-bit quantization. The CMOS camera 5 is used to record the final image.

[0046] In other embodiments, the pixel array of the CMOS camera 5 is B×C, wherein the value range of B is 1280-2048, and the value range of C is 1024-2048.

[0047] The present invention also provides a radiation imaging method based on a special-shaped LYSO:Ce image conversion screen, comprising the following steps:

[0048] S1. Build a radiation imaging system based on a special-shaped LYSO:Ce image conversion screen, and set the entrance of the metal dark box 6 toward a radiation source with high intensity in the center and low intensity in the periphery;

[0049] S2. The high-intensity radiation generated at the center of the radiation source is irradiated onto the central portion 12 of the special-shaped LYSO:Ce image conversion screen 1, and the low-intensity radiation generated around the radiation source is irradiated onto the peripheral portion 11 of the special-shaped LYSO:Ce image conversion screen 1;

[0050] S3, adjusting the optical lens 3 so that the visible light focal spot image emitted from the special-shaped LYSO:Ce image conversion screen 1 and reflected by the reflector 2 is focused by the optical lens 3 and then imaged onto the photocathode of the MCP image intensifier 4;

[0051] S4, adjusting the MCP image intensifier 4, so that the MCP image intensifier 4 multiplies and amplifies the received image and then images it to the CMOS camera 5;

[0052] S5. The final image is recorded by the CMOS camera 5, completing the radiation imaging based on the special-shaped LYSO:Ce image conversion screen.

[0053] The technical effects of the present invention are further explained below through experiments and data:

[0054] Experimental conditions and content:

[0055] The present invention experimentally measures the imaging results of a special-shaped LYSO:Ce image conversion screen 1 under radiation.

[0056] The experimental principle diagram is shown in Figure 2 The radiation source is a cobalt source. The gamma rays emitted by the cobalt source have a uniform intensity distribution at all locations and are directly irradiated onto the special-shaped LYSO:Ce image conversion screen 1 of the present invention. The fluorescent image emitted by the special-shaped LYSO:Ce image conversion screen 1 is reflected by the reflector 2 and enters the optical lens 3. After focusing, it is imaged on the photocathode of the MCP image intensifier 4. After multiplication and amplification, the final fluorescent image is recorded by the CMOS camera 5.

[0057] Experimental results and analysis:

[0058] Figure 3 This is the gamma-ray imaging result of a cobalt source using the radiation imaging system based on the special-shaped LYSO:Ce image conversion screen of the present invention. The average grayscale of the central elliptical region of the image is 3000 ADU, while the average grayscale of the surrounding region is 18000 ADU. The average grayscale of the surrounding region is six times that of the central elliptical region. If the intensity of the radiation source at the center is six times that of the surrounding region, the grayscale of the center and surrounding regions of the image ultimately obtained by the radiation imaging system is equivalent.

[0059] Experimental results show that the central grayscale of radiation images obtained by a radiation imaging system based on the shaped LYSO:Ce image conversion screen is reduced to 1 / 6 of the grayscale of the surrounding images. Therefore, in the imaging diagnosis of radiation sources with higher central intensity than surrounding intensity, the shaped LYSO:Ce image conversion screen 1 can reduce the central grayscale of the radiation source's radiation image, achieving consistency between the central image and surrounding image grayscale.

[0060] The radiation imaging system based on the special-shaped LYSO:Ce image conversion screen of the present invention reduces the central image grayscale of the radiation image by reducing the thickness of the central area of the LYSO:Ce image conversion screen. The thickness of the central part 12 of the special-shaped LYSO:Ce image conversion screen 1 is set to 1 / 5 of the thickness of the peripheral part 11, so that the central image grayscale of the radiation image can be reduced to 1 / 6 of the grayscale of the surrounding images, thereby achieving the purpose of consistent grayscale of the central image and the surrounding images during the image diagnosis process of a type of radiation source with higher central intensity than peripheral intensity.

[0061] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the specific technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the present invention.

Claims

1. A special-shaped LYSO:Ce image conversion screen, characterized by: having a peripheral portion (11) and a central portion (12); The central portion (12) is located in the middle of the peripheral portion (11); The back surface of the peripheral portion (11) and the back surface of the central portion (12) are located in the same plane, and the back surface of the peripheral portion (11) and the back surface of the central portion (12) together form the light emitting surface of the special-shaped LYSO:Ce image conversion screen; The thickness between the front and back sides of the peripheral portion (11) is 1 mm to 10 mm, and the thickness between the front and back sides of the central portion (12) is 1 / 5 of the thickness between the front and back sides of the peripheral portion (11).

2. The special-shaped LYSO:Ce image conversion screen according to claim 1, characterized in that: The front and peripheral surfaces of the special-shaped LYSO:Ce image conversion screen are both blackened.

3. The special-shaped LYSO:Ce image conversion screen according to claim 2, characterized in that: The outer surfaces of the special-shaped LYSO:Ce image conversion screen are all polished surfaces with a roughness of less than 50nm.

4. The special-shaped LYSO:Ce image conversion screen according to any one of claims 1 to 3, characterized in that: The thickness between the front and back sides of the peripheral portion (11) is 5 mm, and the thickness between the front and back sides of the central portion (12) is 1 mm.

5. The special-shaped LYSO:Ce image conversion screen according to claim 4, characterized in that: The shape of the peripheral part (11) is a rectangular parallelepiped, and the length and width of the peripheral part (11) are both 20 mm; The front of the central part (12) is in the shape of an ellipse, the total length of the major axis of the ellipse is 10 mm, the total length of the minor axis of the ellipse is 9 mm, and the geometric center of the front of the central part (12) coincides with the geometric center of the front of the peripheral part (11).

6. A radiation imaging system based on a special-shaped LYSO:Ce image conversion screen, characterized by: It comprises a metal dark box (6), a reflector (2), an optical lens (3), an MCP image intensifier (4), a CMOS camera (5), and the special-shaped LYSO:Ce image conversion screen (1) according to any one of claims 1 to 5; The metal dark box (6) is provided with an entrance port through which the focal spot image of the radiation emitted by the radiation source can pass; The special-shaped LYSO:Ce image conversion screen (1) is arranged at a position close to the incident port and close to the radiation source, and is used for receiving the ray focal spot image emitted by the radiation source and converting it into a visible light focal spot image before emitting it; The reflector (2) is arranged in the emission direction of the special-shaped LYSO:Ce image conversion screen (1) and is used to reflect the visible light focal spot image emitted from the light-emitting surface of the special-shaped LYSO:Ce image conversion screen (1); The optical lens (3), the MCP image intensifier (4) and the CMOS camera (5) are sequentially arranged on the reflection light path of the reflector (2); the optical lens (3) is used to focus the visible light focal spot image reflected by the reflector (2) and then image it to the MCP image intensifier (4); the MCP image intensifier (4) is used to multiply and amplify the received image and then image it to the CMOS camera (5); and the CMOS camera (5) is used to record the final image.

7. The radiation imaging system based on the special-shaped LYSO:Ce image conversion screen according to claim 6, characterized in that: The reflecting surface of the reflector (2) forms an angle of 45° with the optical axis of the special-shaped LYSO:Ce image conversion screen (1); and the optical lens (3) is a zoom lens with an adjustable focal length within the range of 70 mm to 200 mm.

8. The radiation imaging system based on the special-shaped LYSO:Ce image conversion screen according to claim 7, characterized in that: The diameters of the photocathode and the fluorescent screen of the MCP image intensifier (4) are both 25 mm, the photocathode material is an S20 multi-alkali photocathode, the fluorescent screen type is P20, the static spatial resolution of the MCP image intensifier (4) is greater than 50 lp / mm, and the gain voltage of the MCP image intensifier (4) is adjustable within the range of 0 to 5 V.

9. The radiation imaging system based on the special-shaped LYSO:Ce image conversion screen according to claim 8, characterized in that: The chip of the CMOS camera (5) is coupled to the fluorescent screen of the MCP image intensifier (4) through a light cone, and the fluorescent screen image of the MCP image intensifier (4) is imaged onto the chip of the CMOS camera (5). The pixel array of the CMOS camera (5) is B×C, wherein the value range of B is 1280 to 2048, and the value range of C is 1024 to 2048.

10. A radiation imaging method based on a special-shaped LYSO:Ce image conversion screen, characterized in that: The following steps are involved: S1. Build a radiation imaging system based on a special-shaped LYSO:Ce image conversion screen as described in any one of claims 6 to 9, and set the entrance of the metal dark box (6) toward a radiation source with high intensity in the center and low intensity in the periphery; S2, causing the high-intensity radiation generated at the center of the radiation source to irradiate the central portion (12) of the special-shaped LYSO:Ce image conversion screen (1), and causing the low-intensity radiation generated around the radiation source to irradiate the peripheral portion (11) of the special-shaped LYSO:Ce image conversion screen (1); S3, adjusting the optical lens (3) so that the visible light focal spot image emitted from the special-shaped LYSO:Ce image conversion screen (1) and reflected by the reflector (2) is focused by the optical lens (3) and then imaged onto the photocathode of the MCP image intensifier (4); S4, adjusting the MCP image intensifier (4), so that the MCP image intensifier (4) multiplies and amplifies the received image and then images it to the CMOS camera (5); S5. The final image is recorded by the CMOS camera (5), completing the radiation imaging based on the special-shaped LYSO:Ce image conversion screen.

Images