A device for protecting the connection and transmission between optical fiber and photomultiplier tube

Abstract

The present invention relates to a device for protecting the docking transmission of optical fibers and photomultiplier tubes, comprising: a protective shell, which 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; the protective shell has a notch at the end close to the small-diameter hole; a pressure block, which is arranged on the notch of the protective shell and is fixed to the protective shell by a first connector; a bundled optical fiber assembly, whose output end extends from the small-diameter hole of the protective shell and is compressed by the pressure block; a PMT, which extends from the large-diameter hole end of the protective shell and docks with the bundled optical fiber assembly, and the PMT is fixed to the protective shell by a second connector. According to the characteristics of the transmission optical fiber and the photomultiplier tube, the present invention designs a light-shielding structure, adopts a light-shielding and shock-absorbing process, and realizes double-layer light-shielding and process shock-absorbing protection during the transmission process of the optical fiber and the photomultiplier tube.

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 connection transmission between an optical fiber and a photomultiplier tube. Background Art

[0002] The primary scientific objectives of the Very Large Area Gamma-ray Space Telescope (VLAST) are to search for evidence of candidate dark matter particles and monitor gamma-ray emissions from astronomical events such as gravitational waves. VLAST's outermost anticoincidence detector is used to distinguish photons from charged particles. The principle is that a plastic scintillator (SSC) on the surface of the anticoincidence detector detects low-energy photons (1MeV to 10MeV). An optical fiber transmits the low-energy photon signals detected by the SSC. These signals are then converted to electrical signals by a photomultiplier tube (PMT), which then outputs them for analysis. During transmission, coupling the optical fiber to the PMT presents a technical challenge. First, ensuring medium- and long-distance fiber transmission without breakage is crucial. Second, to ensure efficient signal transmission, the bundled fiber end faces must be aligned with the PMT end faces for coupling. Furthermore, considerations must be given to vibration damping and light shielding at the interface between the two end faces.

[0003] Currently, most 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 response to the above problems, the purpose of the present invention is to provide a device for protecting the docking transmission between optical fiber and photomultiplier tube. According to the characteristics of the transmission optical fiber and photomultiplier tube, a light-shielding structure is designed, and a light-shielding and vibration-absorbing process is adopted to achieve double-layer light-shielding and process vibration-absorbing protection during the transmission process of the optical fiber and photomultiplier tube.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] The device for protecting the docking and transmission of optical fibers and photomultiplier tubes described in the present invention includes: a protective shell, which is a shell structure having 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 the 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, the output end of which extends through the small-diameter hole of the protective shell and is compressed by the pressing block; a PMT, which extends through the large-diameter hole end of the protective shell and docks with the bundled optical fiber assembly, and the PMT is fixed to the protective shell by a second connecting piece.

[0007] 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 several of the optical fibers is arranged in the scintillator, and the other end extends out of the scintillator; the extended part of each of the optical fibers is covered with the heat shrink tube and bundled into one; the sleeve is sleeved on the bundled optical fibers, and light-proof tape is wrapped around the sleeve and the optical fibers after glue is injected.

[0008] In the device, preferably, the pressing block is a block structure having 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.

[0009] In 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 provided 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.

[0010] In the device, preferably, the photomultiplier tube is wrapped with shock-absorbing foam.

[0011] 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.

[0012] 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.

[0013] The present invention has the following advantages due to the adoption of the above technical solution:

[0014] The present invention provides a feasible solution for the fixation and light-shielding of detector optical fibers for long-distance transmission. According to the characteristics of the transmission optical fiber and the photomultiplier tube, a light-shielding and vibration-absorbing structure is designed, and a light-shielding and vibration-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 vibration-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 transmission efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiment below. The accompanying drawings are for illustration purposes only and are not to be considered as limiting the present invention. Throughout the drawings, the same reference numerals are used to denote the same components. In the drawings:

[0016] Figure 1 This is a three-dimensional schematic diagram of the first direction structure of the docking transmission protection of the present invention;

[0017] Figure 2 This is a three-dimensional schematic diagram of the first direction structure of the docking transmission protection of the present invention;

[0018] Figure 3 This is a three-dimensional schematic diagram of the optical fiber bundle of the present invention;

[0019] Figure 4 It is a schematic diagram of the briquetting structure of the present invention;

[0020] Figure 5 1 is a schematic cross-sectional view of a PMT according to the present invention;

[0021] Figure 6 It is a schematic structural diagram of the voltage divider of the present invention;

[0022] Figure 7 It is a cross-sectional schematic diagram of the docking transmission protection structure of the present invention.

[0023] The reference numerals in the figures are as follows:

[0024] 1-protective shell; 2-pressing block; 3-first connecting piece; 4-bunching 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 grease gasket. DETAILED DESCRIPTION

[0025] Exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although 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. Rather, these embodiments are provided 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.

[0026] The present invention provides a device for protecting the connection and transmission between optical fibers and photomultiplier tubes. The device comprises: a hole of a corresponding depth is opened at one end of the protective shell according to the diameter of the output end of the bundled optical fiber assembly; a hole of a corresponding diameter and depth is milled at the other end of the protective shell according to the diameter of the photomultiplier tube; the optical fibers are bundled and placed into an aluminum alloy sleeve, and glue is poured into the sleeve so that the optical fibers, the aluminum alloy sleeve, and the solidified glue form a bonded bundled optical fiber; the photomultiplier tube is wrapped with foam, and a silicon stop washer is attached to the cross section of the photomultiplier tube; the integrally bundled optical fiber and the foam-wrapped photomultiplier tube are docked into the shell at both ends through stepped holes and then secured with a pressing block. Light-proof glue is injected into the gap between the integral protective shell and the pressing block, and light-proof tape is applied to the gap. This prevents optical fiber breakage, ensures that the photomultiplier tube is not squeezed and ruptured, and prevents vibration in special circumstances.

[0027] like Figure 1 and Figure 2 As shown, the device for protecting the connection and transmission between an optical fiber and a photomultiplier tube provided by the present invention comprises:

[0028] 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; the 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; the optical fiber bundle assembly 4 (see Figure 3 ), its output end extends into the small-diameter hole of the protective shell 1 and is pressed by the pressing block 2; the PMT (photomultiplier tube assembly) 5 extends into the large-diameter hole end of the protective shell 1 and is connected to the bundled optical fiber assembly 4. The PMT5 and the protective shell 1 are fixed by a second connecting member 6, wherein the second connecting member 6 can be a socket head hexagon screw.

[0029] In the above embodiment, preferably, Figure 3 As shown, the bundled fiber assembly 4 includes: a scintillator 401, optical fibers 402, a heat shrink tubing (not shown), and a sleeve 403. One end of a plurality of optical fibers 402 is disposed within the scintillator 401, and the other end extends out of the scintillator 401. The extended portion of each optical fiber 402 is wrapped with a heat shrink tubing and bundled together. The sleeve 403 is sleeved over the bundled optical fibers 402, and light-shielding tape is wrapped between the sleeve 403 and the optical fibers 402 after adhesive is injected. The scintillator 401 is made of plastic, commonly referred to as a plastic scintillator, and the sleeve is made of aluminum alloy.

[0030] 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.

[0031] 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 member 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 provided 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 member 504, wherein the third connecting member can be a screw.

[0032] In the above embodiment, preferably, the photomultiplier tube 501 is wrapped with shock-absorbing foam (not shown in the figure), thereby improving the shock-absorbing performance.

[0033] In the above embodiment, preferably, Figure 7 As shown, the present invention further includes a silicone grease gasket 7; the silicone grease 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, specifically, it can be bonded to the butt joint end of the photomultiplier tube 501 of the PMT.

[0034] 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, a double-layer process for light protection can be achieved.

[0035] 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 various 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; the protective shell has a notch at the end near the small-diameter hole; A pressing block is arranged on the notch of the protective shell and is fixed to the protective shell via a first connecting member; The output end of the optical fiber bundle assembly extends into the small-diameter hole of the protective shell and is pressed by the pressing block; The PMT extends into the large-diameter hole end of the protective shell 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 includes: a scintillator, an optical fiber, a heat shrink tube and a sleeve; One end of a plurality of optical fibers is disposed 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 then bundled into one; The sleeve is sleeved on the bundled optical fibers, and light-shielding tape is wrapped 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 includes: a photomultiplier tube, a voltage divider, a voltage divider housing, a second connecting piece, and a spacer tube; 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 disposed 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 housing are connected as one 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 grease 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 applied to the gaps.

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