Lens focusing measurement device

Abstract

The utility model discloses a lens focusing measuring device, including optical fiber interface subassembly, section mirror subassembly, lens subassembly, plane mirror subassembly, optical filter subassembly and PSD subassembly, optical fiber interface subassembly connects optical fiber, and the light is collimated and hits on section mirror subassembly, and the light is reflected after section mirror subassembly and transmits through lens subassembly and hits on plane mirror subassembly, and after vertical reflection of plane mirror subassembly, again transmits through lens subassembly, and after focusing of optical filter piece group, hits on PSD sensor. The utility model discloses clever position setting, makes section mirror only reflect half incident light, thereby avoids the reflection of the reflection of plane mirror behind, realizes the measurement of lens focal length, and has adjusting device in multiple fixed positions, and effectively guarantees installation accuracy.

Description

Technical Field

[0001] This utility model relates to the field of focal length measurement, and in particular to a lens focusing measurement device. Background Technology

[0002] In high-precision lens focal length measurement, a laser light source combined with a separate photodetector is typically used. To eliminate the influence of cross terms in the Gaussian mode, half of the PSD sensor needs to receive the light source, which poses a significant challenge to the system design. For example, the lens focal length measuring device described in CN109186961A uses a rotating baffle and a semi-transparent, semi-reflective mirror as its structure. While this theoretically achieves the design objective and provides a good approach for focusing measurement device design, the semi-transparent, semi-reflective mirror has a high manufacturing cost, and the rotating baffle and semi-transparent, semi-reflective mirror require high installation precision; without corresponding adjustment mechanisms, it is difficult to achieve the design objective. Utility Model Content

[0003] Purpose of the utility model: The purpose of this utility model is to provide a lens focal length measuring device with a simple structure and multi-dimensional adjustability.

[0004] Technical Solution: To achieve the above objectives, the lens focusing measurement device of this utility model includes an optical fiber interface assembly, a faceted mirror assembly, a lens under test assembly, a plane mirror assembly, a filter assembly, and a PSD assembly. The optical fiber interface assembly is connected to an optical fiber, collimates the light, and then strikes the faceted mirror assembly. After being reflected by the faceted mirror assembly, the light passes through the lens under test assembly and strikes the plane mirror assembly. After being vertically reflected by the plane mirror assembly, the light passes through the lens under test assembly again, is focused by the filter assembly, and then strikes the PSD sensor of the PSD assembly.

[0005] The fiber optic interface assembly includes a fiber optic interface adapter, a fiber optic interface adjuster, a collimating lens one, and a collimating lens one barrel. The fiber optic interface is mounted on the fiber optic interface adjuster via the fiber optic interface adapter. The fiber optic interface adjuster is connected to the collimating lens one barrel via a threaded connection. The collimating lens one barrel is fixed to the base plate of the device via a collimating lens barrel fixing assembly. The collimating lens one is fixed on the collimating lens one barrel.

[0006] The collimating lens barrel fixing assembly includes a front support block, a front upper pressure block, a rear support block, and a rear upper pressure block. The front upper pressure block and the rear upper pressure block fix the collimating lens barrel by pressing. The center of the contact surface between the front support block and the base plate is engaged by a pin hole. The contact surface between the rear support block and the base plate has an arc groove, which allows the collimating lens barrel to be rotated and adjusted in the Y-axis direction.

[0007] The faceted reflector assembly includes a faceted reflector, a faceted reflector mount, a faceted reflector X-axis adjustment seat, a faceted reflector Y-axis adjustment seat, and a faceted reflector base plate. The faceted reflector base plate is fixed to the base plate of the device. The faceted reflector X-axis adjustment seat is installed above the faceted reflector base plate. The faceted reflector Y-axis adjustment seat is installed above the faceted reflector X-axis adjustment seat. The faceted reflector mount is installed above the faceted reflector Y-axis adjustment seat and can be rotated and adjusted by engaging with pin holes. The faceted reflector is mounted on the faceted reflector mount.

[0008] A shim is added between the base plate and the base plate of the faceted reflector to adjust the tilt of the faceted reflector.

[0009] The lens assembly under test includes a lens under test, a lens under test upper pressure block, a lens under test support block, and a Z-axis moving stage. The Z-axis moving stage is mounted on the base plate of the device, and the lens under test support block is mounted on the Z-axis moving stage. The lens under test is fixed by the lens under test upper pressure block and the lens under test support block through a pressing connection. The lens under test is moved and adjusted in the Z-axis direction by the Z-axis moving stage.

[0010] The planar reflector assembly includes a planar reflector, a planar reflector mount, a planar reflector connecting seat, and an X-axis moving stage. The planar reflector is connected to the planar reflector mount, and the planar reflector mount is mounted on the X-axis moving stage via the planar reflector connecting seat. The X-axis moving stage is mounted on the base plate of the device, and the planar reflector is moved and adjusted in the X-axis direction via the X-axis moving stage.

[0011] The filter assembly includes a second collimating lens, a filter, and a second collimating lens barrel. The second collimating lens and the filter are fixed inside the second collimating lens barrel, and the second collimating lens barrel is fixed to the base plate of the device by a collimating lens barrel fixing assembly.

[0012] The PSD assembly includes a PSD sensor, a PSD sensor backplate, an X-axis moving stage, a PSD sensor connector, and a Y-axis moving stage. The PSD sensor is mounted on the Y-axis moving stage via the PSD sensor backplate, and the Y-axis moving stage is mounted on the X-axis moving stage via the PSD sensor connector. The X-axis moving stage is mounted on the base plate of the device. The PSD sensor backplate has set screw holes, and the tilt angle of the PSD sensor can be adjusted by rotating the set screws.

[0013] Beneficial effects: This utility model has the following advantages: 1. By using a clever position setting, the faceted reflector reflects only half of the incident light from the optical fiber, thereby avoiding the reflected light reflected back by the rear planar reflector, and also replacing the solution using a semi-transparent and semi-reflective mirror; 2. Compared with existing similar designs, a multi-dimensional adjustment mechanism has been added to ensure the installation accuracy of the structure and ensure the feasibility of the measurement scheme. Attached Figure Description

[0014] Figure 1 This is an isometric structural diagram of the present invention;

[0015] Figure 2 This is a lower isometric overall structural diagram of the present invention;

[0016] Figure 3 This is a schematic diagram of the optical principle of the present invention;

[0017] Among them, 1-fiber optic interface, 2-collimating lens one, 3-plane mirror, 4-lens under test, 5-plane mirror, 6-collimating lens two, 7-filter, 8-PSD sensor, 9-plane mirror mount, 10-plane mirror X-axis adjustment mount, 11-plane mirror Y-axis adjustment mount, 12-plane mirror base plate, 13-adjusting screw, 14-collimating lens two barrel, 15-front end support block, 16-front end upper pressure block, 17-rear end support block 18-Rear end pressure block, 19-X-axis moving stage one, 20-Collimating lens barrel one, 21-Fiber optic interface adjuster, 22-Plane mirror mount, 23-Plane mirror connector, 24-Z-axis moving stage, 25-Lens under test support block, 26-Lens under test pressure block, 27-Fiber optic interface adapter, 28-Base plate, 29-PSD sensor back plate, 30-PSD sensor connector, 31-Y-axis moving stage, 32-X-axis moving stage one. Detailed Implementation

[0018] The technical solution of this utility model will be described in detail below with reference to the embodiments and accompanying drawings.

[0019] like Figure 1 and Figure 2 The lens focusing measurement device shown includes a fiber optic interface assembly, a faceted mirror assembly, a lens under test assembly, a plane mirror assembly, a filter assembly, and a PSD assembly. The fiber optic interface assembly connects to an optical fiber. Light emitted from the fiber passes through a collimating lens and strikes the faceted mirror 3, is reflected by the faceted mirror 3, passes through the lens under test 4, strikes the rear plane mirror 5, and is finally reflected by the plane mirror 5, passing through the lens under test 4, the collimating lens 2, and the filter 7 to strike the PSD sensor 8. Furthermore, as shown... Figure 3 As shown, due to the position of the faceted reflector 3, the faceted reflector 3 only reflects half of the incident light from the optical fiber, thereby avoiding the reflected light reflected back by the rear planar reflector.

[0020] The fiber optic interface assembly includes a fiber optic interface adapter 27, a fiber optic interface conditioner 21, a collimating lens 3, a collimating lens barrel 20, and a collimating lens barrel fixing assembly. The fiber optic interface adapter 27 connects to the optical fiber and is mounted on the fiber optic interface conditioner 21. The fiber optic interface conditioner 21 is connected to the collimating lens barrel 20 via screws. The collimating lens barrel 20 is fixed to the base plate 28 via the collimating lens barrel fixing assembly. The collimating lens 3 is fixed to the collimating lens barrel 20 by adhesive application.

[0021] The fiber optic interface adjuster 21 can be rotated on the collimating lens barrel 20 via a thread, thereby adjusting the distance between the fiber optic interface adapter 27 and the collimating lens barrel 20. The collimating lens barrel 20 has a threaded hole, which can be used to fix the adjusted fiber optic interface adjuster 21 with a set screw.

[0022] The fiber optic interface adapter 27 is a standard part, and different diameter fiber optic probes can be replaced by replacing the fiber optic interface adapter 27.

[0023] The collimating lens barrel fixing assembly includes a front support block 15, a front upper pressure block 16, a rear support block 17, and a rear upper pressure block 18. The front upper pressure block 16 and the rear upper pressure block 18 are fixed to the collimating lens barrel 20 by a screw connection after tightening. Furthermore, the contact surface between the front support block 15 and the base plate 28 is provided with a pin hole, and the contact surface between the rear support block 17 and the base plate 28 is provided with an arc groove, which allows the collimating lens barrel 20 to be rotated with a small arc in the Y-axis direction.

[0024] The faceted mirror assembly includes a faceted mirror 3, a faceted mirror mount 9, a faceted mirror X-axis adjustment seat 10, a faceted mirror Y-axis adjustment seat 11, and a faceted mirror base plate 12. The faceted mirror base plate 12 is connected to the base plate 28 by screws. The faceted mirror X-axis adjustment seat 10 is located above the faceted mirror base plate 12, and the faceted mirror Y-axis adjustment seat 11 is located above the faceted mirror X-axis adjustment seat 10. The faceted mirror mount 9 can be rotated and adjusted by engaging with the faceted mirror Y-axis adjustment seat 11 through pin holes. The faceted mirror 3 is fixed to the faceted mirror mount 9 by adhesive application.

[0025] A shim can be added between the base plate 12 and the base plate 28 of the faceted reflector to adjust the tilt of the faceted reflector 3.

[0026] The X-axis adjustment seat 10 and the Y-axis adjustment seat 11 of the faceted reflector have threaded holes on their sides, which are connected to adjusting screws 13. The adjusting screws 13 can be used to adjust the X-axis adjustment seat 10 of the faceted reflector to move along the X-axis direction on the base plate 12 of the faceted reflector, and to adjust the Y-axis adjustment seat 11 of the faceted reflector to move along the Y-axis direction on the X-axis adjustment seat 10 of the faceted reflector.

[0027] The lens assembly under test includes a lens under test 4, a lens under test upper pressure block 26, a lens under test support block 25, and a Z-axis moving stage 24. The Z-axis moving stage 24 is connected to the base plate 28 by screws, and the lens under test support block 25 is connected to the Z-axis moving stage 24 by screws. The lens under test 4 is fixed by the lens under test upper pressure block 26 and the lens under test support block 25 by tightening and then connecting with screws. The lens under test 4 can be moved and adjusted in the Z-axis direction through the Z-axis moving stage 24.

[0028] The plane mirror assembly includes a plane mirror 5, a plane mirror mount 22, a plane mirror connector 23, and an X-axis moving stage 32. The plane mirror 5 is fixed to the plane mirror mount 22 by adhesive dispensing. The plane mirror mount 22, the plane mirror connector 23, the X-axis moving stage 32, and the base plate 28 are all connected by screws. The plane mirror 5 can be moved and adjusted in the X-axis direction via the X-axis moving stage 32.

[0029] The filter assembly includes a second collimator 6, a filter 7, a second collimator lens barrel 14, and a collimator lens barrel fixing assembly. The second collimator 6 and the filter 7 are fixed inside the second collimator lens barrel 14 by adhesive dispensing, and the second collimator lens barrel 14 is fixed to the base plate 28 by the collimator lens barrel fixing assembly. The specific fixing method is the same as that of the first collimator lens barrel 20.

[0030] The PSD assembly includes a PSD sensor 8, a PSD sensor backplate 29, an X-axis moving stage 19, a PSD sensor connector 30, and a Y-axis moving stage 31. The PSD sensor 8, PSD sensor backplate 29, X-axis moving stage 19, PSD sensor connector 30, Y-axis moving stage 31, and base plate 28 are all connected by screws. The PSD sensor 8 can be adjusted in the X and Y axes via the X-axis moving stage 19 and Y-axis moving stage 31. The PSD sensor backplate 29 has set screw holes, allowing adjustment of the tilt angle of the PSD sensor 8 by rotating the set screws.

[0031] Working Principle: The incident laser light is emitted through the fiber optic interface, becomes parallel light through the collimating lens, and is reflected by the faceted mirror. Half of the light is reflected into the lens under test, then reflected again by the plane mirror behind the lens, and finally strikes the PSD sensor after passing through both the lens and the collimating lens. After receiving the information, the PSD sensor adjusts the incident light position, causing a change in the resistance between its two electrodes, resulting in different output currents. Therefore, by measuring the magnitude and ratio of the output currents at the two electrodes, the focal length of the lens under test can be accurately determined. However, because a laser light source is used, when the PSD sensor is very small, Gaussian modes may couple. The cross-terms of these Gaussian modes can significantly affect PSD acquisition. To eliminate this effect, half of the PSD sensor's plane needs to receive the light source.

Claims

1. A lens focusing measuring device, characterized in that: It includes an optical fiber interface assembly, a faceted reflector assembly, a lens under test assembly, a plane reflector assembly, a filter assembly, and a PSD assembly. The optical fiber interface assembly connects to the optical fiber, collimates the light, and hits the faceted reflector assembly. The light is reflected by the faceted reflector assembly and then passes through the lens under test assembly to hit the plane reflector assembly. After being vertically reflected by the plane reflector assembly, it passes through the lens under test assembly again and is focused by the filter assembly to hit the PSD sensor (8) of the PSD assembly.

2. The lens focusing measuring device according to claim 1, characterized in that: The fiber optic interface assembly includes a fiber optic interface adapter (27), a fiber optic interface adjuster (21), a collimating lens one (2), and a collimating lens one tube (20). The fiber optic interface (1) is mounted on the fiber optic interface adjuster (21) via the fiber optic interface adapter (27). The fiber optic interface adjuster (21) is connected to the collimating lens one tube (20) via a threaded rotation. The collimating lens one tube (20) is fixed to the base plate (28) of the device via a collimating lens tube fixing assembly. The collimating lens one (2) is fixed on the collimating lens one tube (20).

3. The lens focusing measuring device according to claim 2, characterized in that: The collimating lens barrel fixing assembly includes a front support block (15), a front upper pressure block (16), a rear support block (17), and a rear upper pressure block (18). The front upper pressure block (16) and the rear upper pressure block (18) fix the collimating lens barrel (20) by pressing. The center of the contact surface between the front support block (15) and the base plate (28) is engaged by a pin hole. The contact surface between the rear support block (17) and the base plate (28) is provided with an arc groove, so that the collimating lens barrel (20) can be rotated and adjusted in the Y-axis direction.

4. The lens focusing measuring device according to claim 1, characterized in that: The faceted reflector assembly includes a faceted reflector (3), a faceted reflector mount (9), a faceted reflector X-axis adjustment seat (10), a faceted reflector Y-axis adjustment seat (11), and a faceted reflector base plate (12). The faceted reflector base plate (12) is fixed on the base plate (28) of the device. The faceted reflector X-axis adjustment seat (10) is installed above the faceted reflector base plate (12). The faceted reflector Y-axis adjustment seat (11) is installed above the faceted reflector X-axis adjustment seat (10). The faceted reflector mount (9) is installed above the faceted reflector Y-axis adjustment seat (11) and can be rotated and adjusted by a pin hole. The faceted reflector (3) is installed on the faceted reflector mount (9).

5. The lens focusing measuring device according to claim 4, characterized in that: A shim is added between the base plate (12) and the base plate (28) of the faceted reflector to adjust the tilt of the faceted reflector (3).

6. The lens focusing measuring device according to claim 1, characterized in that: The lens assembly under test includes a lens under test (4), a lens under test upper pressure block (26), a lens under test support block (25), and a Z-axis moving stage (24). The Z-axis moving stage (24) is mounted on the base plate (28) of the device, and the lens under test support block (25) is mounted on the Z-axis moving stage (24). The lens under test (4) is fixed by the lens under test upper pressure block (26) and the lens under test support block (25) by a pressing connection. The lens under test (4) is moved and adjusted in the Z-axis direction by the Z-axis moving stage (24).

7. The lens focusing measuring device according to claim 1, characterized in that: The planar reflector assembly includes a planar reflector (5), a planar reflector mount (22), a planar reflector connector (23), and an X-axis moving stage (19). The planar reflector (5) is connected to the planar reflector mount (22), and the planar reflector mount (22) is mounted on the X-axis moving stage (19) via the planar reflector connector (23). The X-axis moving stage (19) is mounted on the base plate (28) of the device, and the planar reflector (5) is moved and adjusted in the X-axis direction via the X-axis moving stage (19).

8. The lens focusing measuring device according to claim 1, characterized in that: The filter assembly includes a collimating lens 2 (6), a filter (7), and a collimating lens 2 tube (14). The collimating lens 2 (6) and the filter (7) are fixed inside the collimating lens 2 tube (14), and the collimating lens 2 tube (14) is fixed to the base plate (28) of the device by a collimating lens tube fixing assembly.

9. A lens focusing measuring device according to claim 1, characterized in that: The PSD assembly includes a PSD sensor (8), a PSD sensor backplate (29), an X-axis moving stage (32), a PSD sensor connector (30), and a Y-axis moving stage (31). The PSD sensor (8) is mounted on the Y-axis moving stage (31) via the PSD sensor backplate (29). The Y-axis moving stage (31) is mounted on the X-axis moving stage (19) via the PSD sensor connector (30). The X-axis moving stage (19) is mounted on the base plate (28) of the device. The PSD sensor backplate (29) has set screw holes, and the tilt angle of the PSD sensor (8) is adjusted by rotating the set screws.

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