Device for protecting butt joint transmission of optical fiber and photomultiplier

Abstract

The invention relates to a device for protecting butt joint transmission of an optical fiber and a photomultiplier, and the device comprises a protection housing which is of a housing structure with one end provided with a small-diameter hole and the other end provided with a large-diameter hole, and the small-diameter hole and the large-diameter hole are respectively communicated with an inner cavity of the protection housing; the end, close to the small-diameter hole, of the protective shell is provided with a notch. The pressing block is arranged on the notch of the protective shell and is fixed with the protective shell through a first connecting piece; the output end of the cluster optical fiber assembly extends into the small-diameter hole of the protective shell and is pressed by the pressing block; and the PMT extends from the large-diameter hole end of the protective shell and is in butt joint with the bundled optical fiber assembly, and the PMT and the protective shell are fixed through a second connecting piece. According to the characteristics of the transmission optical fiber and the photomultiplier, a light shielding structure is designed, light shielding and cushioning processes are adopted, and double-layer light shielding and process cushioning protection in the transmission process of the optical fiber and the photomultiplier is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of photoelectric transmission of plastic scintillator detectors, in particular to a device for protecting the butt-joint transmission of an optical fiber and a photomultiplier tube. Background Art

[0002] The main scientific goal of the Very Large Area Gamma-ray Space Telescope (VLAST) is to search for evidence of the existence of candidate dark matter particles and monitor gamma-ray radiation from astronomical events such as gravitational waves. Among them, the outermost anti-coincidence of VLAST is used to distinguish photons from charged particles. The principle is that the plastic flash unit on the surface of the anti-coincidence detector is responsible for detecting low-energy photons (1MeV ~ 10MeV), and the optical fiber transmits the low-energy photon signal detected by the plastic flash unit. The low-energy photon signal transmitted by the optical fiber is converted into an electrical signal after passing through the photomultiplier tube, and then output by the photomultiplier tube for analysis. During the transmission process, the coupling and docking of the optical fiber and the photomultiplier tube is a technical difficulty. First, it is necessary to ensure medium and long-distance optical fiber transmission without breaking. Second, in order to ensure the efficiency of signal transmission, it is necessary to ensure that the end face of the bundled optical fiber is directly coupled with the end of the photomultiplier tube, and it is necessary to consider the problems of shock absorption and light protection at the joint of the two end faces.

[0003] Currently, most of the research on optical fiber protection focuses on the external coating material of the optical fiber to prevent the optical fiber itself from being damaged, but there is a lack of structural protection for the coupling between the optical fiber and other optoelectronic conversion devices. Summary of the invention

[0004] In view of the above problems, the purpose of the present invention is to provide a device for protecting the docking transmission of optical fiber and photomultiplier tube. According to the characteristics of the transmission optical fiber and the photomultiplier tube, a light-shielding structure is designed, and a light-shielding and shock-absorbing process is adopted to achieve double-layer light-shielding and process shock-absorbing protection during the transmission process of the optical fiber and the photomultiplier tube.

[0005] To achieve the above object, the present invention adopts the following technical solutions: The device for protecting the connection and transmission of optical fiber and photomultiplier tube described in the present invention comprises: a protective shell, which is a shell structure with a small diameter hole at one end and a large diameter hole at the other end, and the small diameter hole and the large diameter hole are respectively connected to the inner cavity of the protective shell; the protective shell has a notch at one end close to the small diameter hole; a pressing block is arranged on the notch of the protective shell and is fixed to the protective shell by a first connecting piece; a bundled optical fiber assembly, whose output end extends into the small diameter hole of the protective shell and is pressed by the pressing block; a PMT, which extends into the large diameter hole end of the protective shell and is connected to the bundled optical fiber assembly, and the PMT is fixed to the protective shell by a second connecting piece.

[0006] In the device, preferably, the bundled optical fiber assembly includes: a scintillator, an optical fiber, a heat shrink tube and a sleeve; one end of a plurality of the optical fibers is arranged in the scintillator, and the other end extends out of the scintillator; the extended portion of each optical fiber is covered with the heat shrink tube and bundled into one; the sleeve is sleeved on the bundled optical fiber, and light-proof tape is wrapped after glue is injected between the sleeve and the optical fiber.

[0007] In the device, preferably, the pressing block is a block structure with a step groove, and the step groove matches the output end of the bundled optical fiber assembly, so that when the output end of the bundled optical fiber assembly extends into the protective shell, the pressing block presses the output end of the bundled optical fiber assembly.

[0008] The device, preferably, the PMT includes: a photomultiplier tube, a voltage divider, a voltage divider shell, a second connecting piece and a gasket; the first end of the photomultiplier tube is welded to the voltage divider; the voltage divider shell is a shell structure with one end open and the other end closed; the voltage divider is arranged in the voltage divider shell; a gasket is arranged between the voltage divider and the closed end of the voltage divider shell; the voltage divider, the gasket and the voltage divider shell are connected as a whole through the second connecting piece.

[0009] In the device, preferably, the photomultiplier tube is wrapped with shock-absorbing foam.

[0010] The device preferably further comprises a silicone gasket; the silicone gasket is arranged between the butt joint end of the bundled optical fiber assembly and the butt joint end of the PMT.

[0011] In the device, preferably, light-shielding glue is injected into the contact points between the protective shell and the PMT, the contact points between the protective shell and the pressing block, and the contact points between the protective shell and the bundled optical fiber assembly, and then light-shielding tape is affixed to the gaps.

[0012] The present invention adopts the above technical solution, which has the following advantages: The present invention provides a feasible solution for the fixation and light-shielding of the detector optical fiber for long-distance transmission. According to the characteristics of the transmission optical fiber and the photomultiplier tube, a light-shielding and shock-absorbing structure is designed, and a light-shielding and shock-absorbing process is adopted to achieve double-layer light-shielding and protection of the structure and process. The pressing block applies pressure on the cylindrical surface of the glued and bundled optical fiber. Without directly applying the force to the surface of a single optical fiber, the solid glue also provides shock-absorbing between the optical fiber and the pressing block. In addition, the end face of the optical fiber is made to face the end face of the photomultiplier tube to ensure the transmission efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Throughout the accompanying drawings, the same reference numerals are used to represent the same components. In the accompanying drawings: Figure 1 It is a three-dimensional schematic diagram of the first direction structure of the docking transmission protection of the present invention; Figure 2 It is a three-dimensional schematic diagram of the first direction structure of the docking transmission protection of the present invention; Figure 3 It is a three-dimensional schematic diagram of optical fiber bundling of the present invention; Figure 4 It is a schematic diagram of the briquetting structure of the present invention; Figure 5 Schematic diagram of the cross section of the PMT of the present invention; Figure 6 is a schematic structural diagram of a voltage divider of the present invention; Figure 7 It is a cross-sectional schematic diagram of the docking transmission protection structure of the present invention.

[0014] The reference numerals in the figures are as follows: 1-protective shell; 2-pressing block; 3-first connecting piece; 4-bundled optical fiber assembly; 401-scintillator; 402-optical fiber; 403-sleeve; 5-PMT; 501-photomultiplier tube; 502-voltage divider; 503-voltage divider shell; 504-third connecting piece; 505-gasket; 6-second connecting piece; 7-silicone gasket. DETAILED DESCRIPTION

[0015] The exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0016] The present invention provides a device for protecting the butt-joint transmission of optical fiber and photomultiplier tube, by opening a hole of corresponding depth at one end of the protective shell according to the diameter of the output end of the bundled optical fiber assembly, and milling a hole of corresponding diameter and depth at the other end face of the protective shell according to the diameter of the photomultiplier tube; placing the optical fiber into an aluminum alloy sleeve after bundling, and pouring glue into the sleeve so that the optical fiber, the aluminum alloy sleeve and the condensed solid glue form a glued bundled optical fiber; wrapping the photomultiplier tube with foam, and pasting a silicon stop gasket on the cross section of the photomultiplier tube; the integrally bundled optical fiber and the photomultiplier tube wrapped with foam are respectively butt-jointed into the shell through the two ends of the stepped hole, and then fixed by a pressing block. Light-proof glue is injected into the gap between the integrated protective shell and the pressing block, and light-proof tape is pasted at the gap. In this way, the optical fiber can be prevented from breaking, the photomultiplier tube can be ensured not to be squeezed and broken, and vibration in special circumstances can be prevented.

[0017] like Figure 1 and Figure 2 As shown, the device for protecting the connection transmission between an optical fiber and a photomultiplier tube provided by the present invention comprises: The protective shell 1 is a shell structure having a small diameter hole at one end and a large diameter hole at the other end, wherein the small diameter hole and the large diameter hole are respectively connected to the inner cavity of the protective shell 1; the protective shell has a notch at one end near the small diameter hole; a pressing block 2 is arranged on the notch of the protective shell 1 and fixed to the protective shell 1 by a first connecting member 3, wherein the first connecting member can be a bolt; a clustering optical fiber assembly 4 (see Figure 3 ), the output end of which extends from the small-diameter hole of the protective shell 1 and is pressed by the pressing block 2; the PMT (photomultiplier tube assembly) 5 extends from the large-diameter hole end of the protective shell 1 and is connected to the bundled optical fiber assembly 4, and the PMT5 is fixed to the protective shell 1 by a second connecting member 6, wherein the second connecting member 6 can be a socket head hexagonal screw.

[0018] In the above embodiment, preferably, Figure 3 As shown, the bundled optical fiber assembly 4 includes: a scintillator 401, an optical fiber 402, a heat shrink tube (not shown in the figure) and a sleeve 403; one end of a plurality of optical fibers 402 is arranged in the scintillator 401, and the other end extends out of the scintillator 401; the extended portion of each optical fiber 402 is covered with a heat shrink tube and bundled into one; the sleeve 403 is sleeved on the bundled optical fiber 402, and a light-proof tape is wound after glue is injected between the sleeve 403 and the optical fiber 402. Among them, the scintillator 401 is made of plastic, which is usually called a plastic scintillator; the material of the sleeve is aluminum alloy.

[0019] In the above embodiment, preferably, Figure 4As shown, the pressing block 2 is a block structure with a step groove, which matches the output end of the optical fiber cluster assembly 4, so that when the output end of the optical fiber cluster assembly 4 extends into the protective shell, the pressing block 2 presses the output end of the optical fiber cluster assembly 4.

[0020] In the above embodiment, preferably, Figure 5 and Figure 6 As shown, PMT5 includes: a photomultiplier tube 501, a voltage divider 502, a voltage divider shell 503, a third connecting piece 504 and a gasket 505; the first end of the photomultiplier tube 501 is welded to the voltage divider 502; the voltage divider shell 503 is a shell structure with one end open and the other end closed; the voltage divider 502 is arranged in the voltage divider shell 503; a gasket 505 is arranged between the closed end of the voltage divider 502 and the voltage divider shell 503; the voltage divider 502, the gasket 505 and the voltage divider shell 503 are connected as a whole through the third connecting piece 504, wherein the third connecting piece can be a screw.

[0021] In the above embodiment, preferably, the photomultiplier tube 501 is wrapped with shock-absorbing foam (not shown in the figure), thereby increasing the shock-absorbing performance.

[0022] In the above embodiment, preferably, Figure 7 As shown, the present invention further comprises a silicone gasket 7; the silicone gasket 7 is arranged between the butt joint end of the bundled optical fiber assembly 4 and the butt joint end of the PMT 5, and specifically, can be bonded to the butt joint end of the photomultiplier tube 501 of the PMT.

[0023] In the above embodiment, preferably, light-shielding glue is injected into the contact points between the protective shell 1 and the PMT 5, the contact points between the protective shell 1 and the pressing block 2, and the contact points between the protective shell 1 and the bundled optical fiber assembly 4, and then light-shielding tape is affixed to the gaps; thereby, double-layer process light protection can be achieved.

[0024] 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 technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A device for protecting the connection and transmission between an optical fiber and a photomultiplier tube, characterized in that: include: The protective shell is a shell structure having a small-diameter hole at one end and a large-diameter hole at the other end, wherein the small-diameter hole and the large-diameter hole are respectively connected to the inner cavity of the protective shell; and the protective shell has a notch at one end close to the small-diameter hole; A pressing block, arranged on the notch of the protective shell and fixed to the protective shell via a first connecting member; The output end of the bundled optical fiber assembly extends into the small-diameter hole of the protective shell and is pressed by the pressing block; The PMT extends into the protective shell from the large diameter hole end and docks with the bundled optical fiber assembly. The PMT and the protective shell are fixed by a second connecting piece.

2. The device according to claim 1, characterized in that The bundled optical fiber assembly comprises: a scintillator, an optical fiber, a heat shrink tube and a sleeve; One end of a plurality of the optical fibers is disposed in the scintillator, and the other end extends out of the scintillator; The extended portion of each optical fiber is bundled into one after being covered with the heat shrink tube; The sleeve is sleeved on the bundled optical fibers, and light-shielding tape is wound around the sleeve and the optical fibers after glue is injected.

3. The device according to claim 1, characterized in that The pressing block is a block structure with a step groove, and the step groove matches the output end of the optical fiber cluster assembly, so that when the output end of the optical fiber cluster assembly extends into the protective shell, the pressing block presses the output end of the optical fiber cluster assembly.

4. The device according to claim 1, characterized in that The PMT comprises: a photomultiplier tube, a voltage divider, a voltage divider housing, a second connecting member and a gasket; The first end of the photomultiplier tube is welded to the voltage divider; The voltage divider shell is a shell structure with one end open and the other end closed; The voltage divider is arranged in the voltage divider housing; A gasket tube is provided between the voltage divider and the closed end of the voltage divider housing; The voltage divider, the gasket tube and the voltage divider shell are connected as a whole through the second connecting member.

5. The device according to claim 4, characterized in that The photomultiplier tube is wrapped with shock-absorbing foam.

6. The device according to claim 1, characterized in that Also includes silicone grease gasket; The silicone gasket is arranged between the butt joint end of the optical fiber bundle assembly and the butt joint end of the PMT.

7. The device according to claim 1, characterized in that Light-shielding glue is injected into the contact points between the protective shell and the PMT, the contact points between the protective shell and the pressing block, and the contact points between the protective shell and the bundled optical fiber assembly, and then light-shielding tape is pasted in the gaps.

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