CN217404541U - Microstructure-based scintillating optical fiber, optical fiber array and luminous scintillator - Google Patents
Microstructure-based scintillating optical fiber, optical fiber array and luminous scintillator Download PDFInfo
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- CN217404541U CN217404541U CN202220528056.4U CN202220528056U CN217404541U CN 217404541 U CN217404541 U CN 217404541U CN 202220528056 U CN202220528056 U CN 202220528056U CN 217404541 U CN217404541 U CN 217404541U
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- 239000007787 solid Substances 0.000 claims description 8
- 239000011261 inert gas Substances 0.000 claims description 7
- 238000002955 isolation Methods 0.000 claims description 6
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- 238000010521 absorption reaction Methods 0.000 claims description 5
- 239000011159 matrix material Substances 0.000 claims description 5
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- 239000011148 porous material Substances 0.000 claims 1
- 230000005540 biological transmission Effects 0.000 abstract description 16
- 238000000034 method Methods 0.000 abstract description 11
- 238000009826 distribution Methods 0.000 abstract description 8
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- 230000005251 gamma ray Effects 0.000 description 1
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Abstract
The utility model discloses a scintillation optic fibre, fiber array and luminous scintillator based on micro-structure. The problems that the extraction efficiency of the scintillation light is low, the scintillation light is easy to diffuse in the propagation process, and the transmission mode is in Gaussian distribution, so that the imaging quality is reduced are solved. The scintillation optical fiber is characterized in that an optical fiber substrate made of a scintillation material is provided with an outer layer air hole group and an inner layer air hole array; the outer layer air hole group consists of a plurality of first air holes; connecting the centers of all the first air holes and enclosing the first air holes into a regular closed graph; the inner layer air hole array is composed of a plurality of second air holes, and all the second air holes are positioned in the regular closed graph; the aperture of the plurality of second air holes is gradually reduced from the center to the outside, and the aperture of the first air hole is larger than that of the second air hole at the center.
Description
Technical Field
The utility model belongs to nuclear detection and ray, fast neutron formation of image field, concretely relates to scintillation optic fibre, fiber array and luminous scintillator based on micro-structure.
Background
The scintillation detection system has important application in the fields of high-energy physical experiments, nuclear medicine imaging, astronomical detection, prospecting well logging, security inspection and the like, and often relates to the important requirements of the fields of large scientific engineering or national security.
The scintillator is a core functional material in a scintillation detection system, belongs to a luminescent material, can absorb incident high-energy particles (such as electrons, protons, neutrons, alpha particles and the like) or high-energy photons (such as X rays and gamma rays), converts the energy of the incident high-energy particles into near ultraviolet light or visible light, and then finally realizes the detection of the incident particles or the rays through a photoelectric detection device such as a photomultiplier, a photodiode or a CCD. Common requirements of detection systems for scintillators include high light yield, fast attenuation, matching of emission wavelength to photodetector response, stable physicochemical properties, and low cost, and high density for gamma ray detection.
However, in practical applications, since the inorganic scintillator has a high refractive index (about 1.6-2.2), when the inorganic scintillator emits light due to radiation, scintillation photons inside the scintillator are totally reflected at an exit interface, so that a large number of photons are limited inside the scintillator and cannot exit, even if light smaller than a total reflection angle can exit, since the exit angle covers the whole space, and the detector may be arranged in a certain direction, most of the light at the exit angle cannot enter the detector and is wasted. Meanwhile, the scintillation light is easy to disperse in the process of propagation, and if the transmission mode is in Gaussian distribution, the imaging quality of the scintillation light cannot be obviously improved if the light beam is not regulated and controlled. Therefore, the light output of the scintillator is improved, the emergent directivity of the scintillator is controlled, the transmission process is regulated, and the method has important significance for improving the detection efficiency and sensitivity of a detection system and the imaging quality.
Secondly, in applications of luminescent scintillators with macroscopic dimensions (millimeter to centimeter scale), the temporal characteristics may be spread due to multiple reflections of the scintillating light at the scintillator interface after the scintillator is excited, thereby reducing the time-resolving power of the detection system.
SUMMERY OF THE UTILITY MODEL
In order to solve the extraction inefficiency of scintillation light and to disperse easily at the in-process of propagating, transmission mode is gaussian distribution, leads to reducing the problem that the imaging quality is low, the utility model provides a scintillation optical fiber, fiber array based on micro-structure.
And simultaneously, the utility model also provides a because the luminous scintillator of micro-structure, solved luminous scintillator and had aroused back scintillation light and at scintillator interface department multiple reflection probably lead to the time characteristic dispersion and the problem that scintillation light outgoing efficiency is low.
The utility model discloses a concrete technical scheme as follows:
in a microstructure-based scintillating optical fiber for extracting and transmitting scintillating light, the improvement comprising: an outer layer air hole group and an inner layer air hole array are arranged on an optical fiber substrate made of a scintillating material;
the outer layer air hole group consists of a plurality of first air holes; connecting the centers of all the first air holes and enclosing the first air holes into a regular closed graph;
the inner layer air hole array is composed of a plurality of second air holes, and all the second air holes are positioned in the regular closed graph;
the aperture of the plurality of second air holes is gradually reduced from the center to the outside, and the aperture of the first air hole is larger than that of the second air hole at the center.
Further, the diameters of the plurality of second air holes are gradually reduced in a spiral shape from the center to the outside.
Further, the regular closed figure is a circle, an ellipse, a regular polygon or a rectangle;
further, the first air hole and the second air hole are circular, oval, regular polygon or rectangular.
Further, all the first air holes are filled with an organic liquid scintillation material or a solid scintillator material or inert gas, wherein the refractive index of the organic liquid scintillation material or the solid scintillator material is lower than that of the optical fiber base material; all the second air holes are filled with organic liquid scintillation materials or solid scintillation materials or inert gases with the refractive index lower than that of the optical fiber matrix materials.
Furthermore, the optical fiber substrate is made of an inorganic scintillator material or a plastic scintillator material.
And simultaneously, the utility model also provides a scintillation fiber array based on microstructure, including a plurality of foretell scintillation fibers, be provided with miscellaneous light and nuclear radiation ray absorption isolation layer between a plurality of scintillation fibers and a plurality of scintillation fiber periphery.
Further, the scintillating fiber array is regular polygon or parallelogram or circle.
Additionally, the utility model also provides a luminous scintillator based on micro-structure for arouse out visible light, this scintillator includes the block, its characterized in that: the block body is provided with an outer layer air hole group and an inner layer air hole array;
the outer layer air hole group consists of a plurality of first air holes; connecting the centers of all the first air holes and enclosing the first air holes into a regular closed graph;
the inner layer air hole array is composed of a plurality of second air holes, and all the second air holes are positioned in the regular closed graph;
the aperture of the plurality of second air holes is gradually reduced from the center to the outside, and the aperture of the first air hole is larger than that of the second air hole at the center;
all the first air holes and the second air holes are filled with an organic liquid scintillation material or a solid scintillator material or an inert gas, wherein the refractive index of the organic liquid scintillation material is lower than that of the bulk material.
Furthermore, the interior of the regular closed graph is circular or elliptical or regular polygonal or rectangular; the first air hole and the second air hole are circular, elliptic, regular polygonal or rectangular; the block body is made of an inorganic scintillator material or a plastic scintillator material.
Compared with the prior art, the utility model has the advantages of:
1. the utility model discloses a set up outer air hole group and inlayer air hole array on scintillation optical fiber base member, all second air hole apertures in the inlayer air hole array are gradient shape from inside to outside and reduce gradually, and all be less than the first air hole aperture of outer air hole group, make the air hole part refracting index of whole micro-structure fiber interface present low-height-low distribution, make scintillation light restrict in optic fibre or fiber array in transmission process, realize flexible closed transmission, be difficult for dispersing, realize the even regulation and control in light field simultaneously.
2. The utility model discloses a set up outer air hole group and inlayer air hole array on luminous scintillator, all second air hole apertures reduce gradually from inside to outside being the gradient shape in the inlayer air hole array, and all be less than the first air hole aperture of outer air hole group, the design of this micro-structure has avoided luminous scintillator quilt arouse back scintillation light take place the dispersion that multiple reflection probably leads to time characteristic in luminous scintillator interface department, thereby reduce the problem of detection system's time resolution ability, the inside scintillation photon of scintillator has been solved simultaneously can produce the total reflection at the exit interface, lead to a large amount of photons to be restricted the unable outgoing in the inside of scintillator, lead to the unable problem of effectively extracting of scintillation light.
3. The utility model provides a but scintillation optical fiber, fiber array can realize the transmission of the flexible bending of scintillation light, enlarge the application scene, and imaging quality and resolution ratio are high.
Drawings
Fig. 1 is a schematic structural diagram of the present embodiment.
Fig. 2 is a schematic view of a refractive index distribution region in this embodiment.
Fig. 3 is a mode field diagram of transmission of flare light in the optical fiber of the present embodiment.
Fig. 4 is a diagram of a fiber transmission mode field with a solid center.
FIG. 5 is a diagram of a transmission mode field of an optical fiber having a uniform air hole microstructure.
FIG. 6 is a graph showing the flat distribution of the transmission energy of the optical fiber in the optical fiber of this embodiment.
FIG. 7 is a schematic diagram of a microstructure of a cross section of an optical fiber with air holes in a spiral structure.
Fig. 8 is a single structure diagram of a scintillation optical fiber array with optical fibers arranged in a regular hexagonal array.
Fig. 9 is a single structure diagram of a scintillation optical fiber array with optical fibers arranged in a square array.
FIG. 10 is a diagram of a scintillation fiber array after fusion and stretching by splicing.
The reference numbers are as follows:
1-optical fiber substrate, 2-outer layer air hole group, 3-inner layer air hole array, 21-first air hole, 31-second air hole, 4-scintillating optical fiber, 5-stray light and nuclear radiation ray absorption isolation layer.
Detailed Description
In order to make the aforementioned objects, features and advantages of the present invention more comprehensible, embodiments accompanied with figures are described in detail below, and it is obvious that the described embodiments are some, but not all embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by a person having ordinary skill in the art without creative efforts shall belong to the protection scope of the present invention.
In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, but the present invention may be implemented in other ways different from the specific details set forth herein, and one skilled in the art may similarly generalize the present invention without departing from the spirit of the present invention, and therefore the present invention is not limited to the specific embodiments disclosed below.
Meanwhile, in the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "front, rear, inner and outer" and the like are directions or positional relationships based on the drawings, and are only for convenience of description of the present invention and simplification of description, but not for indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and thus should not be construed as limiting the present invention. Furthermore, the terms first, second, or third are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
The terms "mounted, connected and connected" in the present application are to be understood broadly, unless otherwise explicitly stated or limited, for example: can be fixedly connected, detachably connected or integrally connected: they may be mechanically, electrically, or directly connected, or indirectly connected through intervening media, or may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.
The present embodiment provides a microstructure-based scintillating fiber and a fiber array prepared from the fiber, as shown in fig. 1, which is a cross-sectional view of the microstructure-based scintillating fiber, and the microstructure-based scintillating fiber includes: an optical fiber matrix 1 made of scintillating material, an outer layer air hole group 2 and an inner layer air hole array 3;
the outer layer air hole group is composed of 2 first air holes 21; connecting the centers of all the first air holes 21 and enclosing the centers into a regular closed graph; the regular closed figure in this embodiment is a regular hexagon.
The inner-layer air hole array 3 is composed of a plurality of second air holes 31, and all the second air holes 31 are positioned in the regular closed graph;
the hole diameter of the first air holes 21 is larger than the hole diameter of the second air holes 31; the largest diameter of the plurality of second air holes 31 is the second air hole 31 at the center, and the diameters of the plurality of second air holes 31 gradually decrease from the center to the outside. Assuming that the refractive index of the central region of the inner air hole array 33 is n 1 (e.g., the region within the dashed circle A in FIG. 2), the refractive index n of the region formed by the outer air hole group 2 3 (e.g., the annular region between dashed circle B and dashed circle C in FIG. 2), and a refractive index n in the region between them 2 (e.g., the annular region between dashed circle A and dashed circle B in FIG. 2), then n is 1 <n 2 >n 3 The refractive index of the air hole portion of the entire microstructure fiber interface exhibits a low-high-low distribution. This kind of structure can realize the even regulation and control in light beam light field, specifically as shown in fig. 3, the utility model discloses a gradient index of refraction's micro-structure scintillation optic fibre, scintillation light energy distribution is more even during the transmission, explains that the light field of light beam transmission is more even, and the homogeneity regulation and control in light beam light field can be realized to this structure. Fig. 4 is a diagram of a mode field of an optical fiber with a solid center, and fig. 5 is a diagram of a mode field of an optical fiber with all air holes set to a uniform aperture. FIG. 4,5 in comparison with fig. 3, it can be seen that the energy transmission of the scintillation light in fig. 4 and 5 is gaussian distributed, and this mode affects the final imaging quality. Fig. 6 is a graph showing that the transmission energy of the optical fiber in the optical fiber is evenly distributed, and further proves that the optical fiber designed by the utility model can realize the uniform transmission of energy.
In addition to this embodiment, the regular closed figure may also be a circle or an ellipse or other regular polygon or rectangle. The inner air hole array can be a regular hexagon as shown in fig. 1, and can also be any shape such as a square or oval shape, a circle or other regular polygons.
Preferably, in the present embodiment, the diameters of the plurality of second air holes 31 are spirally decreased from the center to the outside, as shown in fig. 7.
The first air holes 21 and the second air holes 31 may be in any shape such as a circular shape, an oval square shape, a triangular shape, or other regular polygonal shapes, and in the present embodiment, the first air holes 21 and the second air holes 31 are circular.
The first air hole 21 and the second air hole 31 may be filled with an organic liquid scintillator having a lower refractive index than the optical fiber base material, or may be filled with a solid scintillator material having a lower refractive index than the optical fiber base material or an inert gas.
In this embodiment, the fiber matrix may be an inorganic scintillator material, including but not limited to: one or more of nai (tl), csi (tl), zns (ag), BGO, etc. may be a plastic scintillator material, including but not limited to: EJ200, EJ230, NE213, ST401, NE102A, NE 104.
As shown in fig. 8, the present embodiment provides a single scintillation fiber array formed by the above scintillation fibers, the single scintillation fiber array includes a plurality of scintillation fibers 4, and a stray light and nuclear radiation ray absorption isolation layer 5 is disposed between the plurality of scintillation fibers 4 and at the periphery of the plurality of scintillation fibers 4, and the purpose of the arrangement of the stray light and nuclear radiation ray absorption isolation layer 5 is to avoid crosstalk between the scintillation fibers.
The manufacturing method of the optical fiber array monomer comprises the following two steps:
the first method is as follows: the method is directly manufactured by adopting a plurality of scintillating fibers according to a cutting-splicing mode, but the method has higher requirements on the manufacturing process and is more complicated in implementation process.
The second method is as follows: the method comprises the steps of inserting scintillating optical fibers with larger diameters into a prefabricated rod made of porous scintillating optical fibers and a stray light composite isolation layer, improving pixel elements of an optical fiber array by a prefabricated rod stretching method, and improving the total pixel number of the whole optical fiber array by cutting, splicing, fusing and stretching a plurality of stretched optical fiber array monomers.
The detection area of the scintillation fiber array can be regular hexagon as shown in fig. 8 or square as shown in fig. 9, or can be other shapes such as parallelogram, polygon, circle, etc. without being limited to the above shapes, and the structure shown in fig. 10 is a scintillation fiber array with a larger matrix and higher resolution obtained by cutting, splicing, fusing and stretching the scintillation fiber array monomer as shown in fig. 8.
Claims (10)
1. A microstructure-based scintillating optical fiber for extracting and transmitting scintillating light, characterized in that: an outer layer air hole group and an inner layer air hole array are arranged on an optical fiber substrate made of a scintillating material;
the outer layer air hole group consists of a plurality of first air holes; connecting the centers of all the first air holes and enclosing the first air holes into a regular closed graph;
the inner layer air hole array is composed of a plurality of second air holes, and all the second air holes are positioned in the regular closed graph;
the aperture of the plurality of second air holes is gradually reduced from the center to the outside, and the aperture of the first air hole is larger than that of the second air hole at the center.
2. The microstructure-based scintillating optical fiber of claim 1, wherein: the pore diameters of the plurality of second air holes are spirally and gradually reduced from the center to the outside.
3. The microstructure-based scintillating optical fiber of claim 1, wherein: the regular closed figure is a circle or an ellipse or a regular polygon or a rectangle.
4. The microstructure-based scintillating optical fiber of claim 1, wherein: the first air hole and the second air hole are circular or elliptical or regular polygonal or rectangular.
5. The microstructure-based scintillating optical fiber of claim 3, wherein: all the first air holes are filled with organic liquid scintillation materials or solid scintillation materials or inert gases with the refractive index lower than that of the optical fiber matrix materials; all the second air holes are filled with organic liquid scintillation materials or solid scintillation materials or inert gases with the refractive index lower than that of the optical fiber base materials.
6. The microstructure-based scintillating optical fiber of claim 1, wherein: the optical fiber substrate is made of inorganic scintillator material or plastic scintillator material.
7. A microstructure-based scintillating fiber array, characterized by: comprises a plurality of scintillating optical fibers according to claims 1-6, and stray light and nuclear radiation ray absorption isolation layers are arranged among the plurality of scintillating optical fibers and at the periphery of the plurality of scintillating optical fibers.
8. The microstructure-based scintillating optical fiber array of claim 7, wherein: the scintillation fiber array is regular polygon or parallelogram or round.
9. A microstructure-based luminescent scintillator for exciting visible light, the scintillator comprising a mass, characterized in that: the block body is provided with an outer layer air hole group and an inner layer air hole array;
the outer layer air hole group consists of a plurality of first air holes; connecting the centers of all the first air holes and enclosing the centers into a regular closed graph;
the inner layer air hole array is composed of a plurality of second air holes, and all the second air holes are positioned in the regular closed graph;
the aperture of the plurality of second air holes is gradually reduced from the center to the outside, and the aperture of the first air hole is larger than that of the second air hole at the center;
all the first air holes and the second air holes are filled with an organic liquid scintillation material or a solid scintillator material or an inert gas, wherein the refractive index of the organic liquid scintillation material is lower than that of the bulk material.
10. The microstructure-based luminescent scintillator of claim 9, wherein: the interior of the regular closed graph is circular or elliptical or regular polygonal or rectangular; the first air hole and the second air hole are circular, elliptic, regular polygonal or rectangular; the block body is made of an inorganic scintillator material or a plastic scintillator material.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202220528056.4U CN217404541U (en) | 2022-03-11 | 2022-03-11 | Microstructure-based scintillating optical fiber, optical fiber array and luminous scintillator |
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| CN202220528056.4U CN217404541U (en) | 2022-03-11 | 2022-03-11 | Microstructure-based scintillating optical fiber, optical fiber array and luminous scintillator |
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Effective date of registration: 20240816 Address after: 361000 Banshang Society, Building 2, Xinke Plaza, Torch High tech Zone, Xiamen City, Fujian Province Patentee after: Xiamen Huahai Changqing Technology Co.,Ltd. Country or region after: China Address before: 710119, No. 17, information Avenue, new industrial park, hi tech Zone, Shaanxi, Xi'an Patentee before: XI'AN INSTITUTE OF OPTICS AND PRECISION MECHANICS OF CAS Country or region before: China |