Multi-mode optical fiber high-energy particle probe sensor

Abstract

The invention relates to a multimode optical fiber high-energy particle probe sensor, which can sensitively detect alpha, beta, gamma, X rays or neutrons leaked at slits and micropores, and comprises a multimode quartz optical fiber 1 with a fluorescent wrapping layer on the surface, and at least one end of the optical fiber is coupled and linked with a photoelectric sensor; the multimode quartz optical fiber is a side light-emitting optical fiber, the fluorescent wrapping layer is formed by uniformly wrapping the surface of the optical fiber with at least one fluorescent material and an adhesive after being mixed, the fluorescent material is excited by high-energy particles to generate 400-470nm light, and the light is transmitted by the quartz optical fiber and is interpreted and identified by the photoelectric sensor. The method for detecting the slits or the micropores is effectively solved, and the method can be widely applied to detection of radioactive substances in limited environment sites.

Description

Technical Field

[0001] The invention belongs to the technical field of nuclear detection using fluorescence method. Technical Background

[0002] Radioactive high-energy particles have been used in the fields of medicine, nuclear power, industry, etc. The basic structure of existing fluorescence high-energy particle detectors and imaging devices is: scintillator plus photoelectric sensor. The scintillator is mainly plastic scintillator or inorganic crystal scintillator block or flexible sheet. The main purpose is to detect the amount of radioactive substances in the regional space or plane volume. However, it is impossible to effectively monitor the leakage of fine radioactive substances in slits or micropores in real time, such as the container or cover seal of the radioactive source; pipeline interface slits, building gaps, etc. These slits or micropores are small, narrow, deep, and tortuous. The radioactive substances inside them are not easy to be detected by existing technologies.

[0003] A multimode optical fiber high-energy particle probe sensor of the present invention can sensitively detect α, β, γ, X-rays or neutrons leaking from slits and micropores, and comprises: a multimode quartz optical fiber 1 with a fluorescent coating layer on the surface, at least one end of the optical fiber is coupled to a photoelectric sensor; the multimode quartz optical fiber is a side-emitting optical fiber, the fluorescent coating layer is at least a fluorescent material mixed with an adhesive and uniformly coated on the surface of the optical fiber, the fluorescent material is excited by high-energy particles to generate 400-470nm light, which is transmitted through the quartz optical fiber and is interpreted and identified by the photoelectric sensor.

[0004] The present invention effectively solves the problem of detecting these slits or micropores, and can be widely used for detecting radioactive materials in confined and complex environment sites. Summary of the invention

[0005] A multimode optical fiber high-energy particle probe sensor comprises: a multimode quartz optical fiber with a fluorescent coating layer on the surface, at least one end of the multimode quartz optical fiber 1 is coupled to a photoelectric sensor; the multimode quartz optical fiber 1 is a side-emitting optical fiber that conducts blue light, the fluorescent coating layer is a mixture of fluorescent material 3 and adhesive 2 or a layered adhesive, and is uniformly coated on the surface of the optical fiber, the fluorescent material is excited by high-energy particles to generate 400-470nm light, and is transmitted through the quartz optical fiber to be interpreted and identified by the photoelectric sensor.

[0006] The multimode quartz optical fiber 1 in the present invention is a side-emitting rare earth quartz optical fiber for blue light transmission. For the external blue visible light of 400-470nm, the end point of the quartz optical fiber and the side uniform light guide can enter the interior of the quartz optical fiber. Commercially available ordinary optical fibers are mainly used to transmit invisible near-infrared light signals. The signal reading and input are all at the end points of the optical fiber. At the same time, the surface of the quartz optical fiber is covered with a reflective coating. Short-wave visible light cannot propagate over long distances inside the quartz optical fiber, and reversible side emission cannot be generated. The side-emitting rare earth quartz optical fiber used in the present invention cannot produce a good light guiding effect on red light and green long-wave visible light, but can produce a light guiding effect on blue light.

[0007] The fluorescent material in the present invention is zinc sulfide silver powder, zinc sulfide doped with silver ions is sintered at high temperature to form 7-9 micron particles, and the fluorescent material is zinc sulfide silver that can produce blue light after being excited by α, β, γ, X-ray or neutron radiation, and the intensity of the light emission is proportional to the radiation intensity. The adhesive is polyvinyl toluene, which can produce blue light under high-energy particle radiation. The polyvinyl toluene is dissolved by toluene into a viscous adhesive, and the adhesive tightly combines the fluorescent material with the optical fiber. The adhesive is first evenly coated on the surface of the optical fiber, and the excess zinc sulfide silver powder material is adhered to the adhesive surface by repeated brushing process. After drying, the zinc sulfide silver powder material is densely adhered to the adhesive surface. This method can make the powder material microscopic particles form a dense layer, and its detection luminescence effect is the best. Of course, the adhesive can also be mixed with the fluorescent material and coated on the surface of the optical fiber. The fluorescent material particles will form an accumulation and adhere to the surface of the optical fiber. When the zinc sulfide silver powder material emits weak light, the accumulated particles are easily blocked from each other and cannot be well received and conducted by the optical fiber.

[0008] The fluorescent coating layer in the present invention is composed of one or more layers, and the fluorescent coating layer is composed of an adhesive and a fluorescent material. Multiple layers of fluorescent powder can form a dense fluorescent coating layer, but it is usually less than 3 layers. When detecting gamma rays or neutrons, a light-shielding layer 4 is set on the outermost side of the fluorescent coating layer. The light-shielding layer can detect gamma rays or neutrons during the day. Without the light-shielding layer 4, the detection of high-energy particle radiation requires obtaining fluorescent data in the dark to avoid interference from external light. The fluorescent material for detecting high-energy particles α and β in the present invention is zinc sulfide silver 3, which does not contain a light-shielding layer 4. The light-shielding layer can prevent high-energy particles from exciting the fluorescent material.

[0009] The zinc sulfide silver fluorescent material in the present invention has a particle size of 7-9 microns, and the zinc sulfide silver fluorescent material is sintered at a high temperature to form a cubic phase microcrystalline structure. The zinc sulfide silver fluorescent material can emit 400-470nm blue visible light, and is coated on the surface of the quartz optical fiber with an adhesive, and the thickness is 10-30 microns. The adhesive coating layer has a thickness of 1-5 microns, adheres to the zinc sulfide silver fluorescent material particles, and forms a firm coating after drying.

[0010] The photoelectric sensor in the present invention is coupled with the other end of the quartz optical fiber, and the photoelectric sensor is a photomultiplier tube or a semiconductor photoelectric sensor. The end of the quartz optical fiber is coated with zinc silver sulfide, and its light emission can make the transmission distance longer, but the optical fiber diameter is too thin and the area is too small, and the reception probability is low, so the multi-mode quartz optical fiber with a fluorescent coating layer is bundled to facilitate the detection of radiation at the end point and long-distance transmission. The length of the multi-mode quartz optical fiber in the present invention is 1-100 meters. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 Schematic diagram of a multimode fiber high-energy particle probe In the figure of the present invention: 1 multimode quartz optical fiber, 2 adhesive, 3 fluorescent material, 4 light-shielding layer. Specific implementation methods

[0012] A multimode optical fiber high-energy particle probe sensor, comprising: a multimode quartz optical fiber with a fluorescent coating layer on the surface, at least one end of the multimode quartz optical fiber 1 is coupled to a photoelectric sensor, the optical fiber coupling connection uses an optical fiber sintering device, and is sealed and light-shielded. The multimode quartz optical fiber 1 is a side-emitting optical fiber that transmits blue light, and the multimode rare earth optical fiber can produce good reverse luminescence. The rare earth ion in the quartz optical fiber is ytterbium. The fluorescent coating layer is a mixture of fluorescent material 3 and adhesive 2 or layered adhesion, and is evenly wrapped on the surface of the optical fiber. The fluorescent material is excited by high-energy particles to produce 400-470nm luminescence, which is transmitted through the quartz optical fiber and is interpreted and identified by the photoelectric sensor.

[0013] The multimode quartz optical fiber 1 in the present invention is a side-emitting rare earth quartz optical fiber that conducts blue light. The rare earth multimode quartz optical fiber is an important condition for measuring luminescence, and can efficiently transmit the external 400-470nm blue visible light, while the efficiency of other visible light is less than 5%. The endpoints and side uniform light guides of the quartz optical fiber can enter the interior of the quartz optical fiber. The existing commercially available ordinary optical fibers are mainly used to transmit invisible near-infrared light signals. The signal reading input is all at the optical fiber endpoints. At the same time, the surface of the quartz optical fiber is covered with a reflective coating, which cannot measure luminescence. Short-wave visible light cannot be transmitted over a long distance inside the quartz optical fiber, and reversible side luminescence cannot be generated. The side-emitting rare earth quartz optical fiber used in the present invention cannot produce a good light-guiding effect on red light and green long-wave visible light, but can produce a light-guiding effect on blue light.

[0014] The fluorescent material in the present invention is zinc sulfide silver powder, zinc sulfide doped with silver ions is sintered at a high temperature of 800-1000 degrees to form 7-9 micron particles, and the zinc sulfide silver fluorescent material can produce blue light after being excited by α, β, γ, X-ray or neutron radiation, and the intensity of the light emission is proportional to the radiation intensity. The stronger the radiation irradiation, the higher the light emission brightness, and the more sensitive the optical fiber transmission signal is, such as the commercially available KPT430 fluorescent powder. Other commercially available scintillation crystals are not suitable for use in the present invention, because the crystals cannot be combined with optical fibers and are soft and can be bent at will.

[0015] The adhesive in the present invention is polyvinyl toluene, which is also a traditional plastic scintillator. Polyvinyl toluene itself can produce blue light under high-energy particle radiation. Polyvinyl toluene is dissolved by toluene into a viscous adhesive, and the adhesive tightly combines and connects the fluorescent material with the optical fiber. The adhesive is first evenly coated on the surface of the optical fiber, and the excess zinc sulfide silver powder material is adhered to the adhesive surface through repeated brushing. This dry bonding particle process can effectively produce a dense single-layer phosphor layer. After heating and drying, the zinc sulfide silver powder material is densely adhered to the adhesive surface. This method can make the powder material microscopic particles form a dense layer, and its detection luminescence effect is best. Of course, the adhesive can also be mixed with the fluorescent material and coated on the surface of the optical fiber. The fluorescent material particles will form an accumulation and adhere to the surface of the optical fiber. When the zinc sulfide silver powder material emits weak light, the accumulated particles are easily blocked from each other and cannot be well received and conducted by the optical fiber.

[0016] The fluorescent coating layer in the present invention is composed of one or more layers, and the fluorescent coating layer is composed of an adhesive and a fluorescent material. Multiple layers of fluorescent powder can form a dense fluorescent coating layer, but it is usually less than 3 layers. When detecting gamma rays or neutrons, a light-shielding layer 4 is set on the outermost side of the fluorescent coating layer. The light-shielding layer can detect gamma rays or neutrons during the day. Without the light-shielding layer 4, the detection of high-energy particle radiation requires obtaining fluorescent data in the dark to avoid interference from external light. The fluorescent material for detecting high-energy particles α and β in the present invention is zinc sulfide silver 3, which does not contain a light-shielding layer 4. The light-shielding layer can prevent high-energy particles from exciting the fluorescent material.

[0017] The zinc sulfide silver fluorescent material in the present invention has a particle size of 7-9 microns, and the zinc sulfide silver fluorescent material forms a cubic phase microcrystalline structure when sintered at a high temperature. The phase transition point of the zinc sulfide fluorescent material is 1040 degrees, so the sintering temperature is lower than 1000 degrees. The zinc sulfide silver fluorescent material can emit 400-470nm blue visible light, and is coated on the surface of the quartz optical fiber with an adhesive having a thickness of 10-30 microns. The adhesive coating layer has a thickness of 1-5 microns, adheres to the zinc sulfide silver fluorescent material particles, and forms a firm coating after drying.

[0018] The photoelectric sensor in the present invention is coupled with the other end of the quartz optical fiber. The commercially available photoelectric sensor is a photomultiplier tube or a semiconductor photoelectric sensor. The end of the quartz optical fiber is coated with zinc silver sulfide, and its light emission can make the transmission distance longer, but the optical fiber diameter is too thin and the area is too small, and the reception probability is low. Therefore, the multi-mode quartz optical fiber with a fluorescent coating layer is bundled to facilitate the detection of radiation by the end point and long-distance transmission. The length of the multi-mode quartz optical fiber in the present invention is 1-100 meters. The length is related to the radiation intensity, the applicable scene, and the sensitivity of the photoelectric sensor receiver. The advantages of the present invention are

[0019] The simple structure designed by the present invention can effectively implement radiation leakage determination detection or real-time monitoring of tiny pinholes and gaps in bends, has the characteristics of safety, simplicity and sensitivity, and solves the problem of rapid and intuitive detection of micro-leakage in bends.

[0020] The dry-bonding particle process designed in the present invention forms a single-layer dense arrangement of fluorescent powder materials, greatly improves sensitivity, and effectively solves the problem of low-radiation detection.

[0021] The present invention can be used for nuclear power plant detection, radiation container detection, nuclear storage warehouse data tracking and monitoring, and nuclear pollution detection in caves, underground buildings, ground buildings, containers, etc.

[0022] After describing the preferred embodiments of the present invention above, it should be clear to those skilled in the art that any changes and improvements made to the present invention are within the scope of the present invention without departing from the spirit and scope of the present invention.

Claims

1. A multimode optical fiber high energy particle probe sensor, comprising: A multimode quartz optical fiber with a fluorescent coating layer on the surface, wherein at least one end of the multimode quartz optical fiber is coupled to a photoelectric sensor; Multimode Quartz optical fiber is a side-emitting optical fiber that transmits blue light. The fluorescent coating layer is a mixture of fluorescent material and adhesive or layered adhesion, and is evenly wrapped on the surface of the optical fiber. The fluorescent material is excited by high-energy particles to produce 400-470nm light, which is transmitted through the quartz optical fiber and is interpreted and identified by the photoelectric sensor.

2. A multimode optical fiber high-energy particle probe sensor as described in claim 1, wherein the multimode quartz optical fiber is a side-emitting rare earth quartz optical fiber that conducts blue light, and for blue visible light of 400-470nm, the end points and sides of the quartz optical fiber evenly guide light.

3. A multimode optical fiber high-energy particle probe sensor as described in claim 1, wherein the fluorescent coating layer is composed of one or more layers; and a light-shielding layer is arranged on the outermost side of the fluorescent coating layer when detecting gamma or neutrons.

4. A multimode optical fiber high-energy particle probe sensor as described in claim 1, wherein the fluorescent material is zinc silver sulfide, the adhesive is polyvinyl toluene, the polyvinyl toluene is dissolved by toluene, and the adhesive connects the fluorescent material to the optical fiber in a dense single layer arrangement; the adhesive is evenly coated on the surface of the optical fiber, and the zinc silver sulfide powder material is densely adhered to the surface of the adhesive using a dry bonding particle process.

5. A multimode optical fiber high-energy particle probe sensor as described in claim 1, wherein the zinc sulfide silver fluorescent material has a particle size of 7-9 microns, is coated on the surface of the quartz optical fiber with an adhesive, and has a thickness of 10-30 microns.

6. A multimode optical fiber high-energy particle probe sensor as claimed in claim 1, wherein the photoelectric sensor is coupled to the other end of the quartz optical fiber, and the photoelectric sensor is a photomultiplier tube or a semiconductor photoelectric sensor.

7. A multimode optical fiber high-energy particle probe sensor as claimed in claim 1, wherein the fluorescent material for detecting high-energy particles α and β is zinc silver sulfide.

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