Micro photosensitive surface avalanche transistor center alignment device and correction method thereof

Abstract

The invention relates to a micro photosensitive surface avalanche transistor center alignment device and a correction method thereof. The device comprises a pipe pressing ring 1, a pipe sleeve 2, a pipe pressing ring 3, a group pressing ring 4, an adjusting screw 5, an avalanche transistor 6, a matched universal tool microscope 7 and a matched screwdriver 8. During correction, a universal tool microscope 7 is used for reading the relative coordinates of the outer edge of the tube pressing ring 3 and the center of the photosensitive surface of the avalanche tube, the four adjusting screws 5 are adjusted up, down, left and right after the relative position of the tube pressing ring 3 and the center of the photosensitive surface of the avalanche tube is calculated, and the adjusting screws 5 are used for pushing the tube sleeve 2 and the avalanche tube 6 to move until the coaxiality of the center of the photosensitive surface of the avalanche tube and the outer edge of the tube pressing ring 3 is smaller than 0.03 mm. Therefore, the aim of alignment is fulfilled. The device is mainly used for center calibration of the avalanche transistor with the photosensitive surface diameter not larger than 0.2 mm, has the advantages of being simple in structure, efficient in reset, accurate, stable and the like, and can be applied to occasions with high precision, high speed, high reliability and the like.

Description

Technical Field

[0001] This invention relates to the field of optical equipment technology, specifically to a micro-photosensitive avalanche tube center alignment device and its calibration method. Background Technology

[0002] Avalanche photodiodes (APDs) are highly sensitive photodetectors that convert weak light signals into electrical signals. They have wide applications in laser ranging, laser detection, lidar, optical communication, target detection, and medical imaging. In these applications, the photosensitive surface of the APD needs to be precisely aligned with the incident light to ensure accuracy and sensitivity. However, due to the small area of ​​the APD's photosensitive surface and the potential for mechanical vibration and temperature changes during practical applications, the photosensitive surface may shift from the incident light, affecting detection performance. Therefore, designing an auxiliary device that can precisely align the center of the APD's photosensitive surface is crucial.

[0003] The commonly used APD photosensitive surface alignment method in existing technologies is generally the signal measurement method. This method often relies on manual measurement and can only be performed in a laboratory. During repair and reinstallation, a considerable amount of equipment is required to restore the optical axis position. Obviously, this method has significant limitations in applications requiring high precision, high speed, and high reliability, and suffers from drawbacks and shortcomings such as low alignment accuracy, poor stability, and difficulty in adapting to complex environments.

[0004] In summary, it is of particular importance to design an APD photosensitive surface center alignment device that is simple in structure, efficient in resetting, accurate and stable. Summary of the Invention

[0005] The main objective of this invention is to solve the aforementioned problems in the prior art and provide a device for aligning the center of a small photosensitive surface avalanche tube, comprising an avalanche tube assembly, a tube clamping ring 3, and an adjusting screw 5. A through hole is provided in the tube clamping ring 3, and an adjusting screw hole 17 is provided on the surface of the tube clamping ring 3. The avalanche tube assembly is fitted into the through hole of the tube clamping ring 3, with a gap between them to facilitate movement of the avalanche tube assembly. The adjusting screw 5 is installed in the adjusting screw hole 17 and contacts the avalanche tube assembly. By screwing in or out the adjusting screw 5, the avalanche tube assembly can be moved up, down, left, and right to ensure that its small photosensitive surface is coaxial with the tube clamping ring 3.

[0006] In the above scheme, the avalanche tube assembly includes a tube clamping ring 1, an avalanche tube 6, and a sleeve 2. The inner wall of the sleeve 2 is threaded, and the outer wall of the tube clamping ring 1 is also threaded. The avalanche tube 6 is installed in the sleeve 2, and the tube clamping ring 1 is fixedly connected to the sleeve 2 via threads, pressing the avalanche tube 6 tightly within the sleeve 2. The maximum outer diameter of the tube clamping ring 1 and the avalanche tube 6 is equal to or close to the maximum inner diameter of the sleeve 2, thus ensuring a reliable assembly connection.

[0007] In the above scheme, a step is provided on the inner wall of the sleeve 2 and a matching step is provided on the outer wall of the avalanche pipe 6. During assembly, the sleeve 2 and the avalanche pipe 6 are limited by the step and locked by the pipe pressure ring 1.

[0008] In the above scheme, the device further includes a pressure ring 4. Threads are provided on the inner wall of the tube pressure ring 3, and matching threads are provided on the outer surface of the pressure ring 4. The avalanche tube assembly is installed in the through hole inside the tube pressure ring 3. The pressure ring 4 is fixedly connected to the tube pressure ring 3 via threads and presses the avalanche tube assembly tightly. The outer diameter of the pressure ring 4 is equal to or close to the maximum inner diameter of the tube pressure ring 3, thus ensuring a reliable assembly connection between the two.

[0009] In the above scheme, a step is provided on the outer surface of the sleeve 2, and the compression ring 4 is fitted onto the step to press and fix the avalanche pipe assembly in the pipe compression ring 3. The inner diameter of the compression ring 4 is equal to or close to the minimum outer diameter of the sleeve 2, so that the two can be reliably assembled and connected.

[0010] In the above scheme, the tube compression ring 3 includes a base and a circular tube vertically fixed on the base. Multiple connecting holes 16 are evenly distributed on the base, and multiple adjusting screw holes 17 are evenly distributed on the circumference of the circular tube. The entire device can be fixed to other equipment through the connecting holes, and the tiny photosensitive surface of the avalanche tube can be adjusted by the adjusting screws installed in the adjusting screw holes.

[0011] In the above scheme, the number of adjusting screws 5 and adjusting screw holes 17 is the same, both being 3-8, preferably 4. These four adjusting screw holes 17 are located at the four positions of the tube pressure ring 3, respectively, in the upper, lower, left, and right directions. After inserting the adjusting screws 5, the avalanche tube 6 can be adjusted from the four directions of upper, lower, left, and right.

[0012] In the above scheme, the diameter of the photosensitive surface of the avalanche tube 6 is no greater than 0.2 mm. Because the photosensitive surface of the avalanche tube is small, calibration is quite difficult.

[0013] In the above scheme, the device also includes a matching universal tool microscope 7. During use, the alignment device for the center of the micro-photosensitive avalanche tube is connected to the universal tool microscope 7. The universal tool microscope 7 is used to observe whether the center of the photosensitive surface of the avalanche tube and the outer edge of the tube pressure ring 3 are coaxial, thereby determining whether adjustment is needed.

[0014] The second objective of this invention is to provide a method for calibrating a small photosensitive avalanche tube using the above-mentioned device, comprising: loosening the pressure ring 4 and connecting the device to a universal tool microscope 7, observing through the universal tool microscope 7 whether the center 11 of the photosensitive surface of the avalanche tube is coaxial with the outer edge of the pressure ring; if so, no adjustment is needed, and the pressure ring 4 is retightened; otherwise, the adjusting screw 5 is adjusted to push the avalanche tube to move until it is coaxial, and the adjusting screw 5 and the pressure ring 4 are tightened.

[0015] Compared with existing similar products or technologies, the progress of this invention is mainly reflected in the following points: (1) The alignment device has the advantages of simple structure, high efficiency of reset, and precision and stability. It can be applied to various occasions with high precision, high speed and high reliability. It can be used indoors and outdoors without environmental or scene limitations. It has high alignment accuracy, good stability and can adapt to various complex environments; (2) It can be used for the center alignment of the photosensitive surface of avalanche tube with a photosensitive surface of no more than 0.2 mm. It can complete the alignment task that cannot be completed by conventional signal measurement method and has higher efficiency; (3) Since the center of the photosensitive surface of the avalanche tube is based on the outer edge of the device, the resetting, maintainability and interchangeability of the alignment device are good when in use. Attached Figure Description

[0016] Figure 1 This is an exploded view of the micro-photosensitive avalanche tube center alignment device described in this invention.

[0017] Figure 2 This is a perspective view of the micro-photosensitive avalanche tube center alignment device described in this invention.

[0018] Figure 3 This is a 3D view of the tube compression ring.

[0019] Figure 4 This is a three-dimensional view of the tube sleeve.

[0020] Figure 5 This is a three-dimensional view of the tube compression ring.

[0021] Figure 6 This is a three-dimensional view of the pressure ring assembly.

[0022] Figure 7 This is a schematic diagram illustrating the principle of calibrating the photosensitive surface of an APD using the device described in this invention.

[0023] Reference numerals: 1-Tube clamping ring, 2-Tube sleeve, 3-Tube clamping ring, 4-Set of clamping rings, 5-Adjusting screw, 6-Avalanche tube, 7-Universal tool microscope, 8-Screwdriver, 9-Retrieval image, 10-Outer edge of tube clamping ring, 11-Center of photosensitive surface of avalanche tube, 12-Thread, 13-Groove, 14-Inner step, 15-Outer step, 16-Connecting hole, 17-Adjusting screw hole. Detailed Implementation

[0024] To enable those skilled in the art to fully understand the technical solutions and beneficial effects of the present invention, a detailed description is provided below in conjunction with specific embodiments and accompanying drawings. It should be emphasized that the following embodiments are merely a small part of the numerous embodiments of the present invention. Besides these, the present invention can have many other embodiments, and any simple improvements made based on these embodiments will fall within the protection scope of the present invention.

[0025] It should also be noted that, to avoid obscuring the invention with unnecessary details, the accompanying drawings only show structures and / or method steps closely related to the technical solutions of the present invention, while omitting other details that are not closely related to the present invention. The term "comprising / including" herein indicates the presence of a feature, element, step, or component, but does not exclude the presence or addition of one or more other features, elements, steps, or components. Unless otherwise specified, the terms "connected" or "linked" can refer not only to a direct connection but also to an indirect connection or a wireless connection involving an intermediary.

[0026] Unless otherwise stated, the descriptions of orientation or positional relationships in this invention, such as "upper," "lower," "left," "right," "front," and "rear," are based on the orientation or positional relationships shown in the accompanying drawings and are used only for the purpose of facilitating the description of this invention and simplifying the description. They are not intended to indicate or imply that the system or element referred to must have a specific orientation or be constructed or operated in a specific orientation, and should not be construed as limiting the technical solution of this invention.

[0027] like Figure 1-2 The device shown is a center alignment device for a miniature photosensitive avalanche tube, mainly comprising a tube clamping ring 1, a tube sleeve 2, a tube clamping ring 3, a set of clamping rings 4, an adjusting screw 5, an avalanche tube 6, and two supporting tools: a universal tool microscope 7 and a screwdriver 8. The avalanche tube 6 is fixed in the tube sleeve 2 and pressed tightly by the clamping ring 1. The resulting assembly is fitted into the tube clamping ring 3 and pressed tightly by the set of clamping rings 4. The adjusting screw 5 passes through the tube clamping ring 3 and contacts the assembly. After loosening the set of clamping rings 4, the center of the miniature photosensitive surface of the avalanche tube 6 can be corrected by screwing in or out the corresponding adjusting screw 5.

[0028] The pipe clamping ring 1 is mainly used to tighten the avalanche pipe 6 assembled inside the pipe sleeve 2, and its structure is as follows: Figure 3 As shown, the entire structure is circular. A thread 12 is provided on the outer circumference of the tube pressure ring 1, and two grooves 13 are symmetrically provided on one end face of it.

[0029] Sleeve 2 is mainly used for assembling avalanche pipe 6, and its structure is as follows: Figure 4As shown, it is a cylindrical tube in shape. Inner steps 14 and outer steps 15 are respectively provided on the inner and outer surfaces of both ends of the tube sleeve 2. A thread 12 is provided on the outer inner wall of the inner step 14, and a groove 13 is provided on the end face of the outer step 15. The tube compression ring 1 and the tube sleeve 2 are fixedly connected by the threads 12 provided on their respective inner and outer walls.

[0030] The tube clamping ring 3 is mainly used to assemble the tube sleeve 2 (i.e., the assembly) of the fixed avalanche tube, and is fixed and adjusted by adjusting screws. Its structure is as follows: Figure 5 As shown. The tube pressure ring 3 has an inverted T-shaped stepped shape, including a circular base and a circular tube coaxially fixed on the circular base, which are connected by a through hole. Four connecting holes 16 are symmetrically distributed on the surface of the circular base to facilitate fixing the entire alignment device to other equipment. An inner step 14 is provided on the inner wall of the circular tube, and four adjusting screw holes 17 are symmetrically provided on the inner wall of the circular tube with a smaller diameter, and four adjusting screws 5 are provided. A thread 12 is provided on the inner wall of the circular tube with a larger diameter, which matches the thread 12 on the outer surface of the pressure ring 4, thereby fixing the two together.

[0031] The compression ring 4 is mainly used to fix the tube sleeve 2 in the tube compression ring 3, and its structure is as follows: Figure 6 As shown. The shape of the compression ring 4 is similar to that of the tube compression ring 1, also being a circular ring. The outer surface of the compression ring 4 is provided with threads 12, and two grooves 13 are symmetrically provided on one end face of it.

[0032] The adjusting screws 5 are mainly used to push the sleeve 2 and adjust its position, thereby correcting the avalanche tube 6 fixed in the sleeve 2. There are four adjusting screws 5, which are inserted vertically into the adjusting screw holes 17 on the tube pressure ring 3 from the four directions of up, down, left, and right. In addition, the number of adjusting screws 5 and adjusting screw holes 17 can also be three, five, or six, etc., which can still achieve the adjustment and correction function.

[0033] The avalanche tube 6 is cylindrical, with an outer step on its outer surface that matches the inner step 14 on the inner wall of the sleeve 2. The photosensitive surface of the avalanche tube 6 can be large or small, with a diameter not exceeding 0.2 mm.

[0034] like Figure 1As shown, the assembly process of the micro-photosensitive avalanche tube center alignment device is as follows: First, the avalanche tube 6 is inserted into the sleeve 2 from the left side, and the two are limited and tightly fitted by the inner and outer steps. Then, the tube clamping ring 1 is inserted into the sleeve 2 from the left side. With the help of the groove 13, the tube clamping ring 1 is rotated to fix it to the sleeve 2 through the inner and outer threads. After tightening, the tube clamping ring 1 presses the avalanche tube 6 into the sleeve 2, thus obtaining the avalanche tube-sleeve-tube clamping ring assembly. Next, the assembly is inserted into the round tube of the tube clamping ring 3 from the right side (the inner and outer walls of the two are not in tight contact, but there is a certain gap, i.e., a certain space for movement). Then, the assembly clamping ring 4 is fitted onto the sleeve 2. With the help of the groove 13, the assembly clamping ring 4 is rotated to fix it to the tube clamping ring 3 through the inner and outer threads. After tightening, the assembly clamping ring 4 presses the sleeve 2 and the assembly together. Finally, four adjusting screws 5 are screwed on so that they pass through the adjusting screw holes 17 on the tube clamping ring 3. The ends of the adjusting screws 5 contact the outer wall of the sleeve 2 to lock and fix it. The assembled micro-photosensitive avalanche tube center alignment device, as shown Figure 2 As shown.

[0035] The method of using the micro-photosensitive avalanche tube center alignment device is as follows: Figure 7 As shown, the specific steps include: Step S1: Assemble the device by centering the micro-photosensitive avalanche tube according to the above method.

[0036] Step S2: Loosen the pressure ring 4, place the avalanche tube center alignment device under the universal tool microscope 7, read the relative coordinates of the outer edge 10 of the tube pressure ring and the center 11 of the avalanche tube photosensitive surface on the reticle image 9 of the universal tool microscope 7, and calculate their relative positions. Use the screwdriver 8 to adjust (screw in or out) the adjusting screws 5 distributed on the upper, lower, left and right positions of the tube pressure ring 3 surface. The adjusting screws 5 push the tube sleeve 2 and the avalanche tube 6 to move synchronously. After adjustment, the coaxiality of the avalanche tube photosensitive surface 11 and the tube pressure ring 3 is less than 0.03mm.

[0037] Step S3: Retighten the pressure ring 4, retract the adjusting screw 5, and then apply adhesive to tighten and secure it. At this point, the entire component, using the outer edge of the pressure ring 3 as a reference, achieves repositionable assembly with other components.

Claims

1. A device for aligning the center of a miniature photosensitive avalanche tube, characterized in that: The device includes an avalanche tube assembly, a tube pressure ring, and an adjusting screw. A through hole is provided inside the tube pressure ring, and an adjusting screw hole is provided on the surface of the tube pressure ring. The avalanche tube assembly is fitted into the through hole inside the tube pressure ring, and the adjusting screw is installed in the adjusting screw hole on the surface of the tube pressure ring and contacts the avalanche tube assembly. Turning the adjusting screw can push the avalanche tube assembly to move inside the tube pressure ring.

2. The micro-photosensitive avalanche tube center alignment device as described in claim 1, characterized in that: The avalanche tube assembly includes a tube compression ring, an avalanche tube, and a sleeve. The inner wall of the sleeve is provided with threads, and the outer wall of the tube compression ring is provided with matching threads. The avalanche tube is installed in the sleeve, and the tube compression ring is fixedly connected to the sleeve through the threads and presses the avalanche tube.

3. The micro-photosensitive avalanche tube center alignment device as described in claim 2, characterized in that: A step is provided on the inner wall of the casing, and a matching step is provided on the outer wall of the avalanche pipe. The casing and the avalanche pipe are limited by the steps.

4. The micro-photosensitive avalanche tube center alignment device as described in claim 2, characterized in that: The device also includes a pressure ring, with threads on the inner wall of the pressure ring and matching threads on the outer surface of the pressure ring. The avalanche tube assembly is installed in the through hole inside the pressure ring, and the pressure ring is fixedly connected to the pressure ring through the threads and presses the avalanche tube assembly.

5. The micro-photosensitive avalanche tube center alignment device as described in claim 4, characterized in that: A step is provided on the outer surface of the casing, and the compression ring is fitted onto the step to press and fix the avalanche pipe assembly in the compression ring.

6. The micro-photosensitive avalanche tube center alignment device as described in claim 1, characterized in that: The tube pressure ring includes a base and a circular tube vertically fixed on the base. At least two connection holes are evenly distributed on the base, and at least three adjusting screw holes are evenly distributed on the circumference of the circular tube.

7. The micro-photosensitive avalanche tube center alignment device as described in claim 6, characterized in that: The number of adjusting screws and adjusting screw holes are the same, and both have 3-8 holes.

8. The micro-photosensitive avalanche tube center alignment device as described in claim 1, characterized in that: The diameter of the photosensitive surface of the avalanche tube is no greater than 0.2 mm.

9. The micro-photosensitive avalanche tube center alignment device as described in claim 1, characterized in that: The device also includes a matching universal tool microscope.

10. A calibration method for a micro-photosensitive avalanche tube, characterized in that... The method includes: loosening the pressure ring, connecting the center alignment device of the micro-photosensitive avalanche tube to a universal tool microscope, and observing whether the center of the photosensitive surface of the avalanche tube is coaxial with the pressure ring through the universal tool microscope; if so, no adjustment is needed, and the pressure ring is tightened again; otherwise, adjust the adjusting screw and use it to push the avalanche tube assembly to move until it is coaxial, and tighten the adjusting screw and the pressure ring.

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