Solid state neutron optical fiber detector and detection method

Abstract

This application provides a solid-state neutron fiber optic detector, comprising a detector sensitive zone cylinder sealed with a solid scintillation material that converts radiation into fluorescence, an optical fiber reflecting device placed at the bottom of the detector sensitive zone cylinder, a wavelength-shifting optical fiber embedded in the solid scintillation material, an optical fiber fixing guide block, a fluorescence converging optical guide, and a transmission optical fiber. Radiation enters the detector sensitive zone cylinder and interacts with the solid scintillation material to generate fluorescence. The wavelength-shifting optical fiber collects the fluorescence and transmits it to both ends. The optical fiber reflecting device fixes one end of the wavelength-shifting optical fiber and reflects the fluorescence from the end face back to the wavelength-shifting optical fiber. The optical fiber fixing guide block positions the wavelength-shifting optical fiber and transmits the fluorescence to the fluorescence converging optical guide. The fluorescence converging optical guide converges the fluorescence from the wavelength-shifting optical fiber to the transmission optical fiber. The transmission optical fiber transmits the fluorescence to a photoelectric conversion device far from the radiation zone. This invention improves the sensitivity and reliability of the detection, reduces signal loss, and ensures stable long-distance transmission of the fluorescence signal.

Description

Technical Field

[0001] This invention relates to the field of information technology, and in particular to a solid-state neutron fiber optic detector and detection method. Background Technology

[0002] Nuclear radiation detection primarily involves detectors for alpha, beta, gamma, and neutrons. These detectors mainly include gas detectors, solid-state scintillation detectors, and semiconductor detectors. Gas detectors work by utilizing the interaction between radiation and a gaseous medium, which ionizes gas molecules to create positive and negative ion charges. These charges move towards the poles of an applied electric field, forming a charge pulse in the external circuit. This pulse is then processed by the external circuit's electronic circuitry to obtain the incident radiation information, thus enabling radiation detection. Gas detectors have a long history and are widely used due to their stability, reliability, ease of use, and resistance to high temperatures and radiation.

[0003] Neutrons are electrically neutral and cannot be detected directly. Neutron detection is achieved through nuclear reactions that convert neutrons into charged particles. The most common and fundamental detection method includes a BF3 gas proportional counter tube. 3 He gas proportional counter tube, 6 Li glass scintillation detectors and fission chambers are used for neutron detection. Currently, the most widely used and highest-performing detectors for neutron detection are those filled with... 3 Helium in He gas ( 3 The He) gas proportional counter tube detector is a type of gas detector. This detector uses neutrons and... 3 He reacts to detect neutrons, neutrons and 3 The reaction of He produces protons (573 keV) and tritium nuclei (191 keV). The protons and tritium nuclei are emitted in opposite directions, ionizing the working gas to produce positive and negative ion charges. These charges are collected by an external high-voltage electric field and converted into an electrical signal. 3 He gas proportional counter tube detectors are widely used due to their high sensitivity, good gamma suppression ratio, ease of use, and good stability. However, this type of detector also has some problems. First, it is still a gas detector, and gas molecules have a limited density, which is lower than that of solids. Neutrons and... 3 The probability of He reacting is very small, therefore its detection efficiency is very low compared to solid-state detectors such as scintillation detectors. The generated charge is as low as fA, making charge acquisition and processing difficult. It is also easily affected by noise and difficult to detect low-dose radiation. Secondly... 3 Helium gas is a crucial component of scattering neutron sources. It is a scarce resource, primarily produced in Russia, and its limited availability has led to severe depletion. This severe shortage is a global issue, significantly hindering scientific research activities at neutron scattering sources. Furthermore, its high price is a major obstacle. 3The need for domestic production of He proportional counting detectors.

[0004] Third, with the vigorous development of nuclear power in my country, a large amount of decommissioned spent fuel needs to be processed and recycled. During spent fuel reprocessing, a large amount of neutrons and gamma rays are generated, requiring regional radiation monitoring. Additionally, regional radiation monitoring is needed for hospital radiological diagnosis and treatment, nuclear power plant monitoring, counter-terrorism emergency response, uranium mining, industrial flaw detection and analysis, radiopharmaceutical manufacturing, and environmental radiation monitoring. These regional radiation monitoring dose ranges are wide, but the lower limit is very low, down to the nGy level, thus requiring highly sensitive detectors. Furthermore, due to the possibility of unexpected self-sustaining or divergent neutron chain reactions caused by changes in local concentrations of fissile materials and the spontaneous fission of fissile materials releasing neutrons, supercritical states and critical accidents may occur. Accidents produce a large number of transient neutrons and gamma rays, causing excessive radiation exposure to nearby personnel, potentially leading to death or explosions. Therefore, to protect public health and the environment, real-time monitoring and alarm systems for nuclear criticality events are necessary. Currently, nuclear criticality monitoring actually uses neutron or gamma regional radiation monitoring, relying on whether the monitored dose exceeds the limit to trigger an alarm. The drawback of this method is that it cannot perform correlation analysis on the obtained neutrons and gamma rays, and therefore cannot identify true nuclear critical events, leading to false alarms or missed alarms. Therefore, it is necessary to design and develop a real-time recording, monitoring, and prediction system for true nuclear critical events, capable of identifying neutron and gamma-ray cascades and recognizing the morphology of nuclear critical events. Furthermore, due to the harsh environment and high radiation levels in the post-processing area, electronic circuits cannot operate there; therefore, it is necessary to develop a radiation-resistant detector capable of simultaneously detecting neutrons and gamma rays. Summary of the Invention

[0005] This invention provides a solid-state neutron fiber detector, mainly comprising:

[0006] The detector includes a detector sensitive zone cylinder sealed with a solid scintillation material that converts radiation into fluorescence, an optical fiber reflector placed at the bottom of the detector sensitive zone cylinder, a wavelength-shifting optical fiber embedded in the solid scintillation material, an optical fiber fixing guide block, a fluorescence converging optical guide, and a transmission optical fiber. Radiation enters the detector sensitive zone cylinder and interacts with the solid scintillation material to generate fluorescence. The wavelength-shifting optical fiber collects the fluorescence and transmits it to both ends. The optical fiber reflector fixes one end of the wavelength-shifting optical fiber and reflects the fluorescence from the end face back to the wavelength-shifting optical fiber. The optical fiber fixing guide block positions the wavelength-shifting optical fiber and transmits the fluorescence to the fluorescence converging optical guide. The fluorescence converging optical guide converges the fluorescence from the wavelength-shifting optical fiber to the transmission optical fiber. The transmission optical fiber transmits the fluorescence to a photoelectric conversion device away from the radiation zone.

[0007] Furthermore, the optical fiber reflection device includes: the optical fiber reflection device is provided with a plurality of recessed cavities matching the diameter of the wavelength-shifting optical fiber; the inner wall of the recessed cavity is coated with a reflective layer to fix the wavelength-shifting optical fiber and reflect the fluorescence escaping from the end face back to the wavelength-shifting optical fiber; the wavelength-shifting optical fiber is inserted into the recessed cavity, and the reflective layer reflects the fluorescence from the end face of the wavelength-shifting optical fiber into the interior of the wavelength-shifting optical fiber and transmits it to the other end.

[0008] Furthermore, the optical fiber fixing guide block includes: the optical fiber fixing guide block is snapped onto the wall of the detector sensitive area cylinder and is provided with multiple positioning holes to fix the wavelength shifting optical fiber bundle to maintain a preset spacing; the optical fiber fixing guide block and the fluorescence converging light guide are connected by coating a coupling agent, and the wavelength shifting optical fiber passes through the positioning holes and enters the fluorescence converging light guide to transmit fluorescence.

[0009] Furthermore, the fluorescence converging optical guide includes: a plurality of curved converging holes for guiding the wavelength-shifting optical fiber, the ends of the curved converging holes being focused at the port of the transmission optical fiber; a cavity filled with a coupling agent is provided at the junction of the transmission optical fibers, the inner wall of the cavity is coated with a reflective layer to reflect scattered fluorescence to the transmission optical fiber; the curved converging holes are filled with a coupling material to connect the wavelength-shifting optical fiber and the port of the transmission optical fiber to avoid fluorescence loss.

[0010] Furthermore, the solid scintillation material and the wavelength-shifting optical fiber include: the solid scintillation material is filled inside the sensitive area of ​​the detector and is in seamless contact with the wavelength-shifting optical fiber; the wavelength-shifting optical fibers are arranged at a preset spacing in the solid scintillation material to collect all fluorescence; after the solid scintillation material generates fluorescence under radiation, the fluorescence directly enters the adjacent wavelength-shifting optical fiber for transmission.

[0011] Furthermore, the transmission optical fiber includes: the transmission optical fiber is vertically connected to the fluorescence converging light guide port through a transmission optical fiber fixing device, and the transmission optical fiber fixing device is threadedly connected to the sensitive area cylinder of the detector; the transmission optical fiber transmits the converged fluorescence to a photoelectric conversion device in a non-radiation environment for photoelectric conversion.

[0012] Furthermore, the curved converging aperture of the fluorescence converging light guide includes: the curved converging aperture presents different bending states according to the position of the wavelength-displaced optical fiber, and the emission ends of all the curved converging apertures converge at the same focal point located at the port of the transmission optical fiber; a reflective layer is provided on the outer wall of the fluorescence converging light guide to reflect the emitted fluorescence back into the curved converging aperture and transmit it to the transmission optical fiber.

[0013] Furthermore, the recessed cavity includes: the recessed cavity has a recessed spherical structure, the length of the recessed cavity matches the diameter of the wavelength-shifting fiber, and the reflective layer covers the entire inner wall of the recessed cavity; the end face of the wavelength-shifting fiber is inserted into the bottom of the recessed cavity, and the reflective layer reflects the fluorescence emitted isotropically from the end face of the wavelength-shifting fiber back to the core of the wavelength-shifting fiber.

[0014] This invention provides a detection method for a solid-state neutron fiber optic detector, comprising the following steps:

[0015] Radiation signal reception and conversion steps: The radiation to be measured is introduced into the sensitive zone of the detector filled with solid scintillation material, and interacts with the solid scintillation material to generate first fluorescence; Fluorescence collection and primary transmission steps: The first fluorescence is collected through a wavelength-shifting optical fiber embedded in the solid scintillation material, and the first fluorescence is converted into a second fluorescence that is more suitable for transmission. The second fluorescence is transmitted to both ends inside the wavelength-shifting optical fiber.

[0016] End-face fluorescence reflection step: At one end of the wavelength-shifting fiber, a reflective structure coated with a reflective layer is used to reflect the second fluorescence emanating from the end face of the wavelength-shifting fiber back into the interior of the wavelength-shifting fiber, so that it is transmitted in reverse.

[0017] Fluorescence transmission and convergence steps: The second fluorescence from the other end of the wavelength-shifting fiber is transmitted to the fluorescence convergence light guide via the positioning structure, and multiple second fluorescence paths are converged to a common focal point through multiple curved converging holes provided inside the fluorescence convergence light guide;

[0018] Fluorescence output and long-distance transmission steps: The convergent fluorescence at the common focal point is coupled into the input end of the transmission optical fiber, and the fluorescence signal is transmitted to a photoelectric conversion device far from the radiation area through the transmission optical fiber;

[0019] And photoelectric conversion and signal processing steps: at the photoelectric conversion device, the received fluorescence signal is converted into an electrical signal, and subsequent processing is performed to obtain radiation information.

[0020] Furthermore, the fluorescence transfer and convergence steps specifically include:

[0021] First, the wavelength-shifting fiber bundle is positioned and guided by an optical fiber fixing guide block with multiple positioning holes, maintaining its preset spacing and guiding it into the fluorescence converging light guide.

[0022] Then, the second fluorescence propagates in the curved converging aperture of the fluorescence converging light guide and gradually changes direction, with the emission ends of all the curved converging apertures converging at the same focal point.

[0023] A reflective layer is coated on the inner wall of the cavity at the focal point to reflect the scattered fluorescence to the input end of the transmission optical fiber.

[0024] The technical solutions provided by the embodiments of the present invention may include the following beneficial effects:

[0025] This invention discloses a radiation detection device based on solid-state scintillation materials and optical fiber technology. Addressing the challenges of efficient collection and long-distance transmission of fluorescence signals in radiation environments, it innovatively integrates solid-state scintillation materials, optical fiber reflectors, wavelength-shifting optical fibers, and fluorescence-focusing optical guides. This solves the problems of high fluorescence signal loss, low transmission efficiency, and radiation interference with photoelectric conversion devices. The invention converts radiation into fluorescence using solid-state scintillation materials, seamlessly embedding wavelength-shifting optical fibers to efficiently collect the fluorescence. The optical fiber reflector uses a reflective layer to reflect fluorescence escaping from the end face back into the fiber. The fluorescence-focusing optical guide precisely focuses the fluorescence onto the transmission fiber through a curved converging aperture and coupling material, ultimately transmitting it to photoelectric conversion devices far from the radiation zone. This achieves efficient signal conversion and protects the equipment from radiation. The overall technical effect is a significant improvement in the sensitivity and reliability of radiation detection, reduced signal loss, and ensures stable long-distance transmission of fluorescence signals, making it suitable for precise monitoring in high-radiation environments. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the structure of a solid-state neutron fiber optic detector according to the present invention;

[0027] Figure 2 This is a cross-sectional view of the arrangement and distribution of the wave-shifting optical fiber in the sensitive area cylinder of the detector according to the present invention;

[0028] Figure 3 This is a structural schematic diagram of the fiber optic reflection device of the present invention;

[0029] Figure 4 This is a schematic diagram of the optical guide structure of the present invention. Detailed Implementation

[0030] The technical solutions of the embodiments of the present invention will be clearly and thoroughly described below with reference to the accompanying drawings. The described embodiments are merely some embodiments of the present invention.

[0031] Example 1

[0032] like Figures 1-4 As shown in the figure, this embodiment of a solid-state neutron fiber detector may specifically include:

[0033] The detector includes a detector sensitive zone cylinder 2 sealed with a solid scintillation material 6 that converts radiation into fluorescence, an optical fiber reflector 1 placed at the bottom of the detector sensitive zone cylinder 2, a wavelength shifting optical fiber 7 embedded in the solid scintillation material 6, an optical fiber fixing guide block 3, a fluorescence converging optical guide 8, and a transmission optical fiber 5.

[0034] Radiation enters the sensitive zone cylinder 2 of the detector and interacts with the solid scintillation material 6 to generate fluorescence. The wavelength-shifting optical fiber 7 collects the fluorescence and transmits it to both ends. The optical fiber reflection device 1 fixes one end of the wavelength-shifting optical fiber 7 and reflects the end face fluorescence back to the wavelength-shifting optical fiber 7.

[0035] The optical fiber fixing guide block 3 positions the wavelength-shifting optical fiber 7 and transmits the fluorescence to the fluorescence converging optical guide 8. The fluorescence converging optical guide 8 converges the fluorescence from the wavelength-shifting optical fiber 7 to the transmission optical fiber 5. The transmission optical fiber 5 transmits the fluorescence to the photoelectric conversion device far from the radiation area.

[0036] The fiber optic reflection device 1 includes: the fiber optic reflection device 1 is provided with a plurality of recessed cavities matching the diameter of the wavelength-shifting fiber 7; the inner wall of the recessed cavity is coated with a reflective layer 12 to fix the wavelength-shifting fiber 7 and reflect the fluorescence emanating from the end face back to the wavelength-shifting fiber 7; the wavelength-shifting fiber 7 is inserted into the recessed cavity, and the reflective layer 10 reflects the fluorescence from the end face of the wavelength-shifting fiber 7 into the interior of the wavelength-shifting fiber 7 and transmits it to the other end.

[0037] The fiber optic fixing guide block 3 includes: the fiber optic fixing guide block 3 is snapped into the wall of the detector sensitive area cylinder 2 and is provided with multiple positioning holes to fix the wavelength displacement fiber 7 bundles to maintain a preset spacing;

[0038] The optical fiber fixing guide block 3 and the fluorescence converging light guide 8 are connected by a coupling agent coated between them. The wavelength shifting optical fiber 7 passes through the positioning hole and enters the fluorescence converging light guide 8 to transmit fluorescence.

[0039] The fluorescence converging optical guide 8 includes: a plurality of curved converging holes for guiding the wavelength-shifting optical fiber 7, the ends of the curved converging holes being focused at the port of the transmission optical fiber 5; a cavity 9 filled with coupling agent is provided at the junction of the transmission optical fibers 5, the inner wall of the cavity 9 is coated with a reflective layer 12 to reflect scattered fluorescence to the transmission optical fiber 5; the curved converging holes are filled with coupling material 11 to connect the wavelength-shifting optical fiber 7 and the port of the transmission optical fiber 5 to avoid fluorescence loss.

[0040] The solid scintillation material 6 and the wavelength-shifting optical fiber 7 are described as follows: the solid scintillation material 6 is filled in the detector sensitive area cylinder 2 and is in contact with the wavelength-shifting optical fiber 7 without gaps; the wavelength-shifting optical fiber 7 is arranged in the solid scintillation material 6 at a preset interval to collect all fluorescence; after the solid scintillation material 6 generates fluorescence under radiation, the fluorescence directly enters the adjacent wavelength-shifting optical fiber 7 for transmission.

[0041] The transmission optical fiber 5 includes: the transmission optical fiber 5 is vertically connected to the port of the fluorescence converging light guide 8 through a transmission optical fiber 5 fixing device; the transmission optical fiber 5 fixing device is threadedly connected to the detector sensitive area cylinder 2; the transmission optical fiber 5 transmits the converged fluorescence to a photoelectric conversion device in a non-radiation environment for photoelectric conversion.

[0042] The curved converging aperture of the fluorescence converging optical guide 8 includes: the curved converging aperture presents different bending states according to the position of the wavelength displacement optical fiber 7, and the emission ends of all the curved converging apertures converge at the same focal point located at the port of the transmission optical fiber 5; a reflective layer 10 is provided on the outer wall of the fluorescence converging optical guide 8 to reflect the emitted fluorescence back into the curved converging aperture and transmit it to the transmission optical fiber 5.

[0043] The recessed cavity includes: the recessed cavity has a recessed spherical structure, the length of the recessed cavity matches the diameter of the wavelength-shifting fiber 7, and the reflective layer 10 covers the entire inner wall of the recessed cavity; the end face of the wavelength-shifting fiber 7 is inserted into the bottom of the recessed cavity, and the reflective layer 10 reflects the fluorescence emitted isotropically from the end face of the wavelength-shifting fiber 7 back to the core of the wavelength-shifting fiber 7.

[0044] Example 2

[0045] The detection method of the solid-state neutron fiber optic detector in this embodiment includes the following steps:

[0046] Radiation signal reception and conversion steps: The radiation to be measured is introduced into the detector sensitive area cylinder 2 filled with solid scintillation material 6, and interacts with the solid scintillation material 6 to generate first fluorescence; Fluorescence collection and primary transmission steps: The first fluorescence is collected by wavelength-shifting optical fiber 7 embedded in the solid scintillation material 6, and the first fluorescence is converted into a second fluorescence that is more suitable for transmission. The second fluorescence is transmitted to both ends inside the wavelength-shifting optical fiber 7.

[0047] End face fluorescence reflection step: At one end of the wavelength-shifting fiber 7, the second fluorescence emanating from the end face of the wavelength-shifting fiber 7 is reflected back into the interior of the wavelength-shifting fiber 7 by a reflective structure coated with a reflective layer 10, so that it is transmitted in reverse.

[0048] Fluorescence transmission and convergence steps: The second fluorescence from the other end of the wavelength shifting fiber 7 is transmitted to the fluorescence convergence light guide 8 via the positioning structure, and multiple second fluorescence paths are converged to a common focal point through multiple curved converging holes provided inside the fluorescence convergence light guide 8.

[0049] Fluorescence output and long-distance transmission steps: The convergent fluorescence at the common focal point is coupled into the input end of the transmission optical fiber 5, and the fluorescence signal is transmitted to the photoelectric conversion device far from the radiation area through the transmission optical fiber 5;

[0050] And photoelectric conversion and signal processing steps: at the photoelectric conversion device, the received fluorescence signal is converted into an electrical signal, and subsequent processing is performed to obtain radiation information.

[0051] In this embodiment, in the fluorescence collection and primary transmission step, the wavelength-shifting optical fiber 7 is arranged without gaps in the solid scintillating material 6 at a preset spacing to maximize the collection of the first fluorescence generated by the solid scintillating material 6.

[0052] In this embodiment, the end face fluorescence reflection step specifically includes: inserting the end face of the wavelength-shifted fiber 7 into the bottom of a recessed cavity with the reflective layer 10 coated on the inner wall, and using the reflective layer 10 to reflect the second fluorescence emitted isotropically from the end face, so that it returns to the fiber core of the wavelength-shifted fiber 7 for continued transmission.

[0053] In this embodiment, the fluorescence transmission and convergence steps specifically include:

[0054] First, the wavelength-shifting fiber 7 bundle is positioned and guided by an optical fiber fixing guide block 3 with multiple positioning holes, maintaining its preset spacing and guiding it into the fluorescence converging light guide 8.

[0055] Then, the second fluorescence propagates in the curved converging aperture of the fluorescence converging light guide 8 and gradually changes direction, with the emission ends of all the curved converging apertures converging at the same focal point.

[0056] A reflective layer 12 is coated on the inner wall of the cavity 9 at the focal point to reflect the scattered fluorescence to the input end of the transmission optical fiber 5.

[0057] In this embodiment, during the fluorescence transmission and convergence steps, an optical coupling agent or coupling material 11 is filled into the interface between the optical fiber fixing guide block 3 and the fluorescence converging light guide 8, the cavity 9 in the curved converging hole, and the cavity 9 at the focal point to reduce fluorescence loss at the interface.

[0058] In this embodiment, during the fluorescence output and long-distance transmission steps, the transmission optical fiber 5 is mechanically connected to the detector sensitive area cylinder 2 through its fixing device, and is kept perpendicularly aligned with the output port of the fluorescence converging light guide 8 to achieve stable fluorescence coupling output.

[0059] In this embodiment, the radiation to be measured in the radiation signal receiving and conversion step is neutron radiation, and the solid scintillation material 6 is a neutron-sensitive scintillation material that can convert neutron radiation into first fluorescence.

[0060] In this embodiment, the method further includes the step of: distinguishing between neutrons and gamma rays by analyzing the amplitude, time correlation, or energy spectrum characteristics of the electrical signal generated by the photoelectric conversion device, or using it for the identification and monitoring of nuclear critical events.

[0061] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A solid state neutron optical fiber detector, characterized by, include: The detector includes a detector sensitive area cylinder (2) sealed with a solid scintillation material (6) that converts radiation into fluorescence, an optical fiber reflector (1) placed at the bottom of the detector sensitive area cylinder (2), a wavelength shifting optical fiber (7) embedded in the solid scintillation material (6), an optical fiber fixing guide block (3), a fluorescence converging optical guide (8), and a transmission optical fiber (5). Radiation enters the sensitive zone cylinder (2) of the detector and interacts with the solid scintillation material (6) to generate fluorescence. The wavelength-shifting fiber (7) collects the fluorescence and transmits it to both ends. The fiber reflection device (1) fixes one end of the wavelength-shifting fiber (7) and reflects the end face fluorescence back to the wavelength-shifting fiber (7). The optical fiber fixing guide block (3) positions the wavelength-shifting optical fiber (7) and transmits the fluorescence to the fluorescence converging optical guide (8). The fluorescence converging optical guide (8) converges the fluorescence from the wavelength-shifting optical fiber (7) to the transmission optical fiber (5). The transmission optical fiber (5) transmits the fluorescence to the photoelectric conversion device far from the radiation area.

2. A solid state neutron optical fiber probe according to claim 1, wherein, The fiber optic reflection device (1) includes: The fiber optic reflection device (1) is provided with a plurality of recessed cavities that match the diameter of the wavelength-shifting fiber (7). The inner wall of the recessed cavity is coated with a reflective layer (12) to fix the wavelength-shifting fiber (7) and reflect the fluorescence emanating from the end face back to the wavelength-shifting fiber (7). The wavelength-shifting fiber (7) is inserted into the recessed cavity, and the reflective layer (10) reflects the fluorescence from the end face of the wavelength-shifting fiber (7) into the interior of the wavelength-shifting fiber (7) and transmits it to the other end.

3. A solid-state neutron fiber optic detector as described in claim 1, characterized in that, The fiber optic fixing guide block (3) includes: The fiber fixing guide block (3) is snapped into the wall (2) of the detector sensitive area cylinder (2) and is provided with multiple positioning holes to fix the wavelength displacement fiber (7) bundle to maintain a preset spacing; The optical fiber fixing guide block (3) and the fluorescence converging optical guide (8) are connected by a coupling agent coated between them. The wavelength shifting optical fiber (7) passes through the positioning hole and enters the fluorescence converging optical guide (8) to transmit fluorescence.

4. A solid-state neutron fiber optic detector as described in claim 1, characterized in that, The fluorescent converging optical guide (8) includes: The fluorescent converging optical guide (8) is provided with a plurality of curved converging holes that guide the wavelength shifting optical fiber (7), and the ends of the curved converging holes are focused at the port of the transmission optical fiber (5); The fluorescent converging optical guide (8) has a cavity (9) filled with coupling agent at the junction of the transmission optical fiber (5), and the inner wall of the cavity (9) is coated with a reflective layer (12) to reflect the scattered fluorescence to the transmission optical fiber (5). The curved converging hole is filled with coupling material (11) to connect the wavelength shifting fiber (7) and the transmission fiber (5) port to avoid fluorescence loss.

5. The solid-state neutron fiber detector as described in claim 1, characterized in that, The solid scintillation material (6) and the wavelength-shifting optical fiber (7) comprise: The solid scintillation material (6) is filled in the detector sensitive area cylinder (2) and is in contact with the wavelength shifting fiber (7) without gaps. The wavelength shifting fiber (7) is arranged in the solid scintillation material (6) at a preset spacing to collect all fluorescence. After the solid scintillation material (6) generates fluorescence under radiation, the fluorescence is directly transmitted into the adjacent wavelength-shifted optical fiber (7).

6. A solid-state neutron fiber optic detector as described in claim 1, characterized in that, The transmission optical fiber (5) includes: The transmission optical fiber (5) is vertically connected to the port of the fluorescence converging light guide (8) through the transmission optical fiber (5) fixing device, and the transmission optical fiber (5) fixing device is threadedly connected to the detector sensitive area cylinder (2). The transmission optical fiber (5) transmits the converged fluorescence to a photoelectric conversion device in a non-radiation environment for photoelectric conversion.

7. A solid-state neutron fiber optic detector as described in claim 4, characterized in that, The curved converging aperture of the fluorescent converging optical guide (8) includes: The curved converging aperture presents different bending states according to the position of the wavelength-shifting optical fiber (7), and the output ends of all the curved converging apertures converge at the same focal point located at the port of the transmission optical fiber (5). The outer wall of the fluorescent converging light guide (8) is provided with a reflective layer (10) to reflect the escaped fluorescence back into the curved converging hole and transmit it to the transmission optical fiber (5).

8. A solid-state neutron fiber optic detector as described in claim 2, characterized in that, The recessed cavity includes: The recessed cavity has a recessed spherical structure, the length of the recessed cavity matches the diameter of the wavelength shifting fiber (7), and the reflective layer (10) covers the entire inner wall of the recessed cavity; The end face of the wavelength-shifting fiber (7) is inserted into the bottom of the recessed cavity, and the reflective layer (10) reflects the fluorescence emitted isotropically from the end face of the wavelength-shifting fiber (7) back to the core of the wavelength-shifting fiber (7).

9. A detection method for a solid-state neutron fiber optic detector as described in claim 1, characterized in that, Includes the following steps: Radiation signal reception and conversion steps: The radiation to be measured is brought into the detector sensitive area cylinder (2) filled with solid scintillation material (6), and interacts with the solid scintillation material (6) to generate the first fluorescence; Fluorescence collection and primary transmission steps: The first fluorescence is collected by a wavelength-shifting fiber (7) embedded in the solid scintillation material (6), and the first fluorescence is converted into a second fluorescence that is more suitable for transmission. The second fluorescence is transmitted to both ends inside the wavelength-shifting fiber (7). End face fluorescence reflection step: At one end of the wavelength shifting fiber (7), the second fluorescence emanating from the end face of the wavelength shifting fiber (7) is reflected back into the interior of the wavelength shifting fiber (7) by using a reflective structure coated with a reflective layer (10), so that it is transmitted in reverse. Fluorescence transmission and convergence steps: The second fluorescence from the other end of the wavelength shifting fiber (7) is transmitted to the fluorescence convergence light guide (8) via the positioning structure, and multiple second fluorescence paths are converged to a common focal point through multiple curved convergence holes provided inside the fluorescence convergence light guide (8); Fluorescence output and long-distance transmission steps: The convergent fluorescence at the common focal point is coupled into the input end of the transmission optical fiber (5), and the fluorescence signal is transmitted to the photoelectric conversion device far away from the radiation area through the transmission optical fiber (5); And photoelectric conversion and signal processing steps: at the photoelectric conversion device, the received fluorescence signal is converted into an electrical signal, and subsequent processing is performed to obtain radiation information.

10. The detection method of the solid-state neutron fiber optic detector as described in claim 9, characterized in that, The fluorescence transfer and convergence steps specifically include: First, the wavelength-shifting fiber (7) bundle is positioned and guided by an optical fiber fixing guide block (3) with multiple positioning holes, maintaining its preset spacing and guiding it into the fluorescence converging light guide (8). Then, the second fluorescence propagates in the curved converging aperture of the fluorescence converging optical guide (8) and gradually changes direction, and the emission ends of all the curved converging apertures converge at the same focal point. A reflective layer (12) is coated on the inner wall of the cavity (9) at the focal point to reflect the scattered fluorescence to the input end of the transmission optical fiber (5).

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