A device and detection method for accurately positioning a convex aspheric surface in a Hindle detection optical path

Abstract

The present invention discloses a device and a detection method for accurately positioning a convex aspheric surface in a Hindle detection optical path, belonging to the technical field of optical testing and optical adjustment. The device comprises an auxiliary positioning device for assembling a convex aspheric surface, a Hindle spherical mirror, and an interferometer arranged on a three-dimensional displacement platform. The cross section of the auxiliary positioning device is a "convex"-shaped structure. The convex side of the auxiliary positioning device is provided with a mounting positioning surface. The center position of the plane side of the auxiliary positioning device is provided with an adjustment reference spherical surface and a reference spherical surface. The outermost circle of the plane side of the auxiliary positioning device is provided with a plurality of top pull screw holes. The present invention uses ultra-precision turning to process an auxiliary positioning device with a mounting positioning surface and a reference spherical surface, uses an interferometer to detect and calibrate the focal plane, and realizes adjustment. The device is convenient for rapid and accurate detection during the development of convex aspheric surfaces, ensures the accuracy of the curvature radius and the aspheric coefficient of the convex aspheric surface, and has the advantages of real-time positioning and high efficiency during the detection process.

Description

Technical Field

[0001] The invention relates to the technical field of optical testing and optical adjustment, and in particular to a device and a detection method for accurately positioning a convex aspheric surface in a Hindle detection optical path. Background Art

[0002] High-precision imaging optical systems often have strict tolerance requirements on the surface shape and geometric parameters of aspheric surfaces. Hindle detection is a commonly used aberration-free point detection method for detecting convex aspheric surfaces, but the positional relationship between the Hindle sphere, convex aspheric surface and interferometer in the detection optical path is often difficult to accurately locate. Among them, high-precision positioning of the convex aspheric surface in Hindle detection is a prerequisite for ensuring the curvature radius and aspheric coefficient of the tested convex aspheric surface. During the adjustment test process, the position and angle of the convex aspheric surface need to be controlled and calibrated simultaneously. Under the traditional adjustment process, Hindle detection uses a single interferometer incident spherical wavefront, and uses multi-dimensional adjustment screws to control the Hindle spherical mirror and convex aspheric surface respectively. The posture of the lens debugging is judged according to the returned wavefront morphology, and the adjustment process of multiple components will be repeated, which greatly reduces the efficiency of building the detection optical path. There is no positioning reference in the optical path, which is not conducive to multiple disassembly during the lens development process.

[0003] Based on the above problems, a device and detection method for accurately positioning the convex aspheric surface in the Hindle detection light path are proposed. Summary of the invention

[0004] The purpose of the present invention is to provide a device and a detection method for accurately positioning a convex aspheric surface in a Hindle detection optical path. An auxiliary positioning device with a mounting positioning surface and a reference spherical surface is processed by ultra-precision turning, and the calibration focal plane is detected by an interferometer to achieve installation and adjustment. The device is convenient for rapid and accurate detection during the development of convex aspheric surfaces, ensures the accuracy of the curvature radius and aspheric coefficients of the tested convex aspheric surfaces, and has the advantages of real-time positioning and high efficiency during the detection process.

[0005] To achieve the above-mentioned purpose, the present invention provides a device for accurately positioning a convex aspheric surface in a Hindle detection optical path, comprising an auxiliary positioning device for assembling a convex aspheric surface, a Hindle spherical mirror, and an interferometer arranged on a three-dimensional displacement platform. The cross-section of the auxiliary positioning device is a "convex"-shaped structure, and a mounting positioning surface is arranged on the convex side of the auxiliary positioning device. An adjustment reference spherical surface and a reference spherical surface are arranged at the center position of the plane side of the auxiliary positioning device, and a plurality of top pulling screw holes are arranged on the outermost circle of the plane side of the auxiliary positioning device.

[0006] Preferably, the center of the adjustment reference spherical surface, the center of the reference spherical surface, and the center of the installation positioning surface are all located on the same horizontal straight line.

[0007] Preferably, a jacking screw is provided on the jacking screw hole.

[0008] Preferably, the interferometer comprises a first interferometer and a second interferometer.

[0009] The present invention proposes a detection method based on a device for accurately positioning a convex aspheric surface in a Hindle detection optical path, comprising the following steps:

[0010] S1. Install the Hindle spherical mirror on the three-dimensional translation platform, use the first interferometer to align the back of the Hindle spherical mirror, adjust the angle and posture, use the second interferometer to find the center position of the Hindle spherical mirror and record the position;

[0011] S2, assemble the convex aspheric surface and the auxiliary positioning device, place them on the three-dimensional displacement platform, use the second interferometer to assist in locating the position of the line connecting the center of the Hindle spherical mirror and the center of the convex aspheric surface, use the line as the axis of the convex aspheric surface, and adjust the top pull screw to control the angle posture of the convex aspheric surface 5;

[0012] S3, move the second interferometer to the center position of the Hindle spherical mirror, so that the center position of the auxiliary positioning device is adjusted to coincide with the center position of the Hindle spherical mirror, use the first interferometer to adjust the axial distance to find the second focal position of the convex aspheric surface, and complete the detection.

[0013] Preferably, in S2, before use, the auxiliary positioning device uses an interferometer and a precision slide rail combination on the three-dimensional translation stage to detect the distance between the installation positioning surface and the center of the reference spherical surface to ensure that the reference spherical surface coincides with the first focal position of the assembled convex aspherical surface.

[0014] Preferably, in S4, the position of the convex aspheric surface is monitored in real time on the second interferometer to achieve high-precision axial positioning, and the surface shape of the convex aspheric surface can be accurately tested on the first interferometer to ensure geometric parameters such as the cone coefficient and curvature radius of the convex aspheric surface.

[0015] Therefore, the device and detection method for accurately positioning the convex aspheric surface in the Hindle detection light path of the present invention have the following beneficial effects:

[0016] (1) The present invention uses the auxiliary adjustment of ultra-precision turning to accurately locate the position of the convex aspheric surface, and can determine the position and posture of the convex aspheric surface in real time according to the interference fringes. It is suitable for rapid and accurate detection during the development of convex aspheric surfaces, improves the adjustment efficiency, and reduces the development cycle and cost.

[0017] (2) The method of the present invention for accurately locating the position of the convex aspheric surface in the Hindle detection light path can ensure the accuracy of the cone coefficient and curvature radius of the convex aspheric surface during the detection process.

[0018] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of the detection of the auxiliary positioning device according to an embodiment of the present invention;

[0020] Figure 2 The structure of the auxiliary positioning device according to the embodiment of the present invention is shown in FIG. Figure 1 ;

[0021] Figure 3 The structure of the auxiliary positioning device according to the embodiment of the present invention is shown in FIG. Figure 2 ;

[0022] Figure 4 Schematic diagram of the Hindle detection optical path precision adjustment method according to the embodiment of the present invention Figure 1 ;

[0023] Figure 5 Schematic diagram of the Hindle detection optical path precision adjustment method according to the embodiment of the present invention Figure 2 ;

[0024] Figure 6 Schematic diagram of the Hindle detection optical path precision adjustment method according to the embodiment of the present invention Figure 3 ;

[0025] Reference numerals:

[0026] 1. Auxiliary positioning device; 101. Adjustment of reference spherical surface; 102. Reference spherical surface; 103. Installation and positioning surface; 104. Pull screw; 2. Hindle spherical mirror; 3. First interferometer; 4. Second interferometer; 5. Three-dimensional translation stage; 6. Convex aspherical surface. DETAILED DESCRIPTION

[0027] The technical solution of the present invention is further described below through the accompanying drawings and embodiments.

[0028] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments.

[0029] Example

[0030] The present invention provides a device for accurately positioning a convex aspheric surface in a Hindle detection optical path, comprising an auxiliary positioning device 1 for assembling a convex aspheric surface 6, a Hindle spherical mirror 2, and an interferometer arranged on a three-dimensional displacement stage 5. Figure 2 , 3 As shown, the cross-section of the auxiliary positioning device 1 is a "convex" shaped structure, and a mounting positioning surface 103 is provided on the convex side of the auxiliary positioning device 1. The mounting positioning surface 103 is used to fix the radial position of the convex aspheric surface 6. An adjustment reference spherical surface 101 and a reference spherical surface 102 are provided at the center position of the plane side of the auxiliary positioning device 1. The reference spherical surface 102 can determine the optical axis direction and axial position of the convex aspheric surface 6; a plurality of top pull screw holes are provided on the outermost circle of the plane side of the auxiliary positioning device 1, and top pull screws 104 are provided on the top pull screw holes.

[0031] The center of the adjustment reference spherical surface 101, the center of the reference spherical surface 102, and the center of the installation positioning surface 103 are all located on the same horizontal straight line.

[0032] The interferometer includes a first interferometer 3 and a second interferometer 4, and the interferometer is used to test the positional relationship between the installation positioning surface 103 and the reference spherical surface 102. When in use, the auxiliary positioning device 1 is assembled with the convex aspherical surface 6, and the distance between the mirrors is accurately positioned by aligning the center of the Hindle spherical mirror 2 with the center of the reference spherical surface 102 to complete the test.

[0033] A detection method is proposed based on the device, comprising the following steps:

[0034] 1) The auxiliary positioning device 1 is processed by ultra-precision turning. The base material is made of metal aluminum alloy. The surface accuracy of the turning process is better than 0.1 micron.

[0035] 2) If Figure 1 As shown, the distance between the installation positioning surface 103 and the center of the reference spherical surface 102 is detected by combining an interferometer and a precision slide rail on the three-dimensional displacement stage 5. The size needs to ensure that the center of the reference spherical surface 102 coincides with the first focal position of the assembled convex aspherical surface 6. The positioning test accuracy is better than 0.5 microns. The auxiliary positioning device 1 is processed and tested for standby use.

[0036] 3) If Figure 4 As shown, the Hindle spherical mirror 2 is mounted on the three-dimensional displacement stage 5, the first interferometer 3 is used to align the back of the Hindle spherical mirror 2, the angle posture is adjusted, and the second interferometer 4 is used to find the center position of the Hindle spherical mirror 2 and record the position;

[0037] 4) If Figure 5As shown, the convex aspheric surface 6 is assembled with the auxiliary positioning device 1 and placed on the three-dimensional displacement stage 5. The second interferometer 4 is used to assist in locating the position of the line connecting the center of the Hindle spherical mirror 2 and the center of the convex aspheric surface 6. The line is used as the axis of the convex aspheric surface 6, and the top pull screw 104 is adjusted to control the angle posture of the convex aspheric surface 6.

[0038] 5) If Figure 6 As shown, the second interferometer 4 is moved to the center position of the Hindle spherical mirror 2 so that the center position of the auxiliary positioning device 1 is adjusted to coincide with the center position of the Hindle spherical mirror 2, and the first interferometer 3 is used to adjust the axial distance to find the second focal position of the convex aspheric surface 6.

[0039] 6) Finally, the position of the convex aspheric surface 6 is monitored in real time on the second interferometer 4 to achieve high-precision axial positioning. The surface shape of the convex aspheric surface 6 can be accurately tested on the first interferometer 3 to ensure geometric parameters such as the cone coefficient and curvature radius of the convex aspheric surface 6.

[0040] Therefore, the present invention provides a device and detection method for accurately positioning the convex aspheric surface in the Hindle detection optical path. An auxiliary positioning device with an installation positioning surface and a reference spherical surface is processed by ultra-precision turning, and the calibration focal plane is detected by an interferometer to achieve installation and adjustment. The device is convenient for rapid and accurate detection during the development of convex aspheric surfaces, ensures the accuracy of the curvature radius and aspheric coefficient of the tested convex aspheric surface, and has the advantages of real-time positioning and high efficiency during the detection process.

[0041] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.

Claims

1. A method for accurately locating a convex aspheric surface in a Hindle detection optical path, characterized in that: The following steps are involved: S1. Install the Hindle spherical mirror on the three-dimensional translation platform, use the first interferometer to align the back of the Hindle spherical mirror, adjust the angle and posture, use the second interferometer to find the center position of the Hindle spherical mirror and record the position; S2. The convex aspheric surface and the auxiliary positioning device are assembled and installed, and placed on a three-dimensional displacement platform. The second interferometer is used to assist in locating the position of the line connecting the center of the Hindle spherical mirror and the center of the convex aspheric surface. The line is used as the axis of the convex aspheric surface, and the top pull screw is adjusted to control the angle posture of the convex aspheric surface. Before using the auxiliary positioning device, the interferometer and the precision slide rail combination on the three-dimensional displacement platform are used to detect the distance between the installation positioning surface and the center of the reference spherical surface to ensure that the reference spherical surface coincides with the first focal position of the assembled convex aspheric surface. S3, moving the second interferometer to the center position of the Hindle spherical mirror, so that the center position of the auxiliary positioning device coincides with the center position of the Hindle spherical mirror, and using the first interferometer to adjust the axial distance to find the second focal position of the convex aspheric surface to complete the detection; using the second interferometer to monitor the position of the convex aspheric surface in real time, and using the first interferometer to accurately test the surface shape of the convex aspheric surface; The device used in the above-mentioned detection method includes an auxiliary positioning device for assembling convex aspheric surfaces, a Hindle spherical mirror, and an interferometer arranged on a three-dimensional displacement platform. The cross-section of the auxiliary positioning device is a "convex"-shaped structure, and the convex side of the auxiliary positioning device is provided with a mounting positioning surface. The center position of the plane side of the auxiliary positioning device is provided with an adjustment reference spherical surface and a reference spherical surface. The outermost circle of the plane side of the auxiliary positioning device is provided with a plurality of top pulling screw holes; the interferometer includes a first interferometer and a second interferometer.

2. According to claim 1, a method for accurately locating a convex aspheric surface in a Hindle detection light path, characterized in that: The center of the adjustment reference spherical surface, the center of the reference spherical surface, and the center of the installation positioning surface are all located on the same horizontal straight line.

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