Measuring device for wavefront of aspheric lens

Abstract

The utility model discloses an aspheric lens wavefront measuring device, and belongs to the technical field of optical elements. The measuring device comprises a measuring support arranged on one side of the interferometer, the outer side of the measuring support is connected with a placement seat, the placement seat is provided with a lens, the side face of the measuring support is further movably connected with a displacement table, the outer side of the displacement table is provided with a mirror bracket, and the mirror bracket is provided with a reflector. Through the arrangement of the measuring bracket, the placing seat, the displacement table and the mirror bracket, the problem that the manual focusing error is relatively large is solved, and the requirements of high-precision equipment can be met; the displacement table drives the guide rail and the platform to move by manually controlling the threaded rod to rotate, so that accurate adjustment of a target position is realized; through the arrangement of the mirror bracket, under the rotation of the adjusting screw rod, the reflecting mirror can be adjusted in three directions, namely two pitching angles and one direction, the adjusting angles are all + / -3 degrees, and through the cooperation between the displacement table and the mirror bracket, the precision of measuring the wavefront of the lens is improved, and the measuring speed is increased.

Description

Technical Field

[0001] The utility model belongs to the technical field of optical elements, and in particular relates to a measuring device for a non-spherical lens wavefront. Background Art

[0002] Aspheric lenses allow optical component designers to correct aberrations using fewer optical elements than traditional spherical elements because the former provide them with more aberration correction than the latter can provide using multiple surfaces. For example, a zoom lens that typically uses ten or more lens elements can use one or two aspheric lenses to replace five or six spherical lenses and achieve the same or better optical effect, reduce production costs, and also reduce the size of the system.

[0003] Wavefront is an important optical indicator of the lens. Whether the wavefront is accurately measured has a great impact on the quality of aspheric lens products. At present, the measurement method of the wavefront of the lens mainly adopts the manual alignment method, which is measured by placing the reflector at the focal length of the lens. In this measurement process, there is a large manual error. From the perspective of traditional technology, most companies currently use manual alignment, which has a large manual error and it is difficult to control the angle of the wave plate optical axis within a small error range. However, with the improvement of the accuracy of instruments and equipment, the error of manual alignment is large, which is greatly related to the proficiency of the operator and has probability, and can no longer meet the needs of high-precision equipment. Utility Model Content

[0004] The utility model aims to provide a device for measuring the wavefront of an aspherical lens in view of the problems existing in the prior art.

[0005] To achieve the above object, the utility model adopts the following technical solution: comprising a measuring bracket arranged on one side of the interferometer, the outer side of the measuring bracket is connected to a placement seat, the placement seat is provided with a lens, the side of the measuring bracket is also movably connected to a displacement platform, the outer side of the displacement platform is installed with a mirror frame, the mirror frame is installed with a reflector, the side of the measuring bracket is also provided with an inclined refractor, the mirror frame is located above the placement seat, and the refractor is located below the placement seat;

[0006] An adjustment component connected to the displacement stage is arranged in the measuring bracket.

[0007] By adopting the above technical solution and measuring the coordination between the bracket and the refractor, the accuracy of measuring the lens wavefront is improved and the measuring speed is accelerated.

[0008] Optionally, a through hole is opened on the surface of the placement seat, a rubber pad with a placement hole is provided on the surface of the placement seat, the placement hole is arranged corresponding to the through hole, and the lens is arranged on the placement hole.

[0009] By adopting the above technical solution, the rubber pad can protect the lens and prevent the lens from being scratched.

[0010] Optionally, a positioning member is provided between the placement seat and the rubber pad, and the positioning member includes a positioning groove opened on the surface of the placement seat, and a positioning column fixedly connected to the rubber pad is provided on the inner side of the positioning groove.

[0011] By adopting the above technical solution and the cooperation between the positioning column and the positioning groove, the appropriate rubber pad can be replaced according to lenses of different sizes.

[0012] Optionally, the lens is aspherical.

[0013] By adopting the above technical solution, the aspherical shape of the lens can correct the aberration of the lens and improve the precision and accuracy of the measurement.

[0014] Optionally, the translation platform is a horizontal translation platform, and a plurality of fixing holes are provided on a surface of the translation platform, and the fixing holes are used to connect fixing bolts.

[0015] By adopting the above technical solution, the fixing bolts and the fixing holes cooperate with each other, so that the connecting seat and the translation platform can be easily disassembled and assembled.

[0016] Optionally, the mirror frame is a three-dimensional optical adjustment frame, and the reflector is located on the mirror frame.

[0017] By adopting the above technical solution and setting the frame, precise adjustment and positioning in three-dimensional space can be achieved to meet the adjustment requirements in different directions.

[0018] Optionally, the adjustment component includes a slot hole opened on the surface of the measuring bracket, the inner wall of the slot hole is movably connected with a threaded column, the outer side of the threaded column is threadedly connected with a threaded seat, the outer side of the threaded seat is fixedly connected with a connecting column, and the end of the connecting column away from the threaded seat is connected to the displacement platform.

[0019] By adopting the above technical solution, the threaded column is rotated, and with the cooperation of the slot hole, the threaded seat on the outer side of the threaded column drives the translation platform to perform large-spacing adjustment through the connecting column.

[0020] Optionally, a movable hole is opened on the top wall inside the slot, and the threaded column is located inside the movable hole, and the lower end of the threaded column is movably connected to the inner wall of the slot through a bearing, and the upper end of the threaded column is fixedly connected to an adjustment seat.

[0021] By adopting the above technical solution, the threaded column can rotate stably through the cooperation between the bearing and the movable hole.

[0022] Compared with the prior art, the beneficial effects of the utility model are:

[0023] By setting up the measuring bracket, placement seat, translation stage and mirror frame, the problem of large manual alignment error can be solved to meet the needs of high-precision equipment; the translation stage drives the guide rail and platform to move by manually controlling the rotation of the threaded rod, thereby achieving precise adjustment of the target position; the setting of the mirror frame allows the reflector to adjust the azimuth in three directions, namely 2 pitches and 1 azimuth, with the adjustment angle of ±3°, by the cooperation between the translation stage and the mirror frame, the accuracy of measuring the lens wavefront is improved and the measurement speed is accelerated. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0025] Figure 2 This is a schematic diagram of the three-dimensional structure of the mirror frame of the utility model;

[0026] Figure 3 This is a schematic diagram of the front view structure of the displacement platform of the utility model;

[0027] Figure 4 For this utility model Figure 1 The enlarged structural diagram at A in the middle;

[0028] Figure 5 This is a schematic diagram of the structure of the adjustment component of the utility model.

[0029] In the figure: 1. measuring bracket; 2. interferometer; 3. placement seat; 301. through hole; 302. rubber pad; 303. positioning groove; 304. positioning column; 4. lens; 5. translation stage; 501. fixing hole; 502. fixing bolt; 6. mirror frame; 7. reflector; 8. refractor; 9. adjustment component; 91. slot hole; 92. threaded column; 921. adjustment seat; 93. threaded seat; 94. connecting column; 941. connecting slot. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the utility model to clearly and completely describe the technical solution of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0031] In the description of the present invention, it should be noted that the directions or positional relationships indicated by terms such as "middle", "upper", "lower", "left", "right", "inside" and "outside" are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0032] like Figure 1 —3, the specific scheme of the embodiment is as follows: it includes a measuring bracket 1 arranged on one side of the interferometer 2, the interferometer 2 is a zygo laser interferometer, the interferometer 2 is an analytical instrument used in the field of materials science, the measuring bracket 1 and the interferometer 2 are on the same horizontal plane, the measuring bracket 1 is "L" shaped, the outer side of the measuring bracket 1 is connected to a placement seat 3, the surface of the placement seat 3 is provided with a through hole 301, the surface of the placement seat 3 is provided with a rubber pad 302 with a placement hole, the placement hole is arranged corresponding to the through hole 301, the lens 4 is arranged on the placement hole, a positioning member is provided between the placement seat 3 and the rubber pad 302, the positioning member includes a positioning groove 303 opened on the surface of the placement seat 3, the inner side of the positioning groove 303 is provided with a positioning column 304 fixedly connected to the rubber pad 302, the positioning column 304 cooperates with the positioning groove 303, so that the rubber pad 302 can be replaced according to the specifications of the lens 4 placement hole;

[0033] A lens 4 is provided on the placement seat 3, and the lens 4 is arranged at the through hole 301. The lens 4 is aspherical. The aspherical shape of the lens 4 can correct aberrations such as spherical distortion and chromatic aberration, so that the optical performance of the lens 4 is more superior, thereby improving the accuracy and reliability of wavefront measurement. The setting of the rubber pad 302 can protect the lens 4 and prevent the placement seat 3 from scratching the lens 4 on its surface.

[0034] The side of the measuring bracket 1 is also movably connected with a displacement platform 5, and a plurality of fixing holes 501 are provided on the surface of the displacement platform 5, and the fixing holes 501 are used to connect fixing bolts 502. The displacement platform 5 includes a threaded rod, a handle, a guide rail, a platform and a base, and the platform is connected to the base through the guide rail. A threaded rod is provided between the platform and the base, and the threaded rod is movably connected to the base. The threaded rod is a spiral mechanism with a certain pitch. The guide rail is usually a linear guide rail, which can ensure that the platform remains stable during the displacement process. As an adjustment and fixing part, the platform can be installed with different tooling and measuring equipment. The platform is usually fixed on the guide rail by screws, clamps, etc. to ensure a stable position. The base is connected to the measuring bracket 1;

[0035] It should be noted that when the user rotates the handle, the pitch of the threaded rod rotates, and at the same time, the guide rail and the platform move together. The larger the pitch, the greater the displacement corresponding to the unit rotation angle, and the higher the adjustment sensitivity, thereby achieving precise adjustment of the target position.

[0036] A mirror frame 6 is installed on the outer side of the displacement stage 5. The mirror frame 6 is a three-dimensional optical adjustment frame. The mirror frame 6 includes a lens fixing plate, a frame fixing plate, three adjusting screws and two preload springs. The lens fixing plate forms a hinge structure with the frame fixing plate through the preload springs. The three adjusting screws are threadedly connected to the frame fixing plate. The head of the adjusting screw is a semi-sphere, which is pressed against the lens fixing plate. A reflector 7 is installed on the mirror frame 6. The reflector 7 is located on the inner side of the lens fixing plate. A threaded hole is opened on the surface of the frame fixing plate. The frame fixing plate is connected to the fixing bolt 502 through the threaded hole. The 3 adjusting screws can be adjusted at the same time by adjusting the screws. There are two pitches and one azimuth, and the adjustment angles are all ±3°. The pitch / azimuth resolution also reaches 0.74° / cycle. There is no restriction of threaded rings on the lens fixing plate. Both the reflected light beam and the transmitted light beam can obtain a larger light aperture. The setting of the frame 6 can realize precise adjustment and positioning in three-dimensional space to meet the adjustment needs in different directions. An inclined refractor 8 is also provided on the side of the measuring bracket 1. The refractor 8 is located at the angle of the measuring bracket 1, and the refractor 8 can refract light. The frame 6 is located above the placement seat 3, and the refractor 8 is located below the placement seat 3.

[0037] The measuring bracket 1 is provided with an adjustment component 9 connected to the displacement stage 5;

[0038] The adjusting assembly 9 includes a slot 91 formed on the surface of the measuring bracket 1. The slot 91 is located in the middle of the measuring bracket 1, and the length of the slot 91 is less than the length of the measuring bracket 1. A movable hole is formed on the top wall of the inner side of the slot 91. A threaded column 92 is movably connected to the inner side wall of the slot 91. The threaded column 92 is located on the inner side of the movable hole, and the lower end of the threaded column 92 is movably connected to the inner side wall of the slot 91 through a bearing. An adjusting seat 921 is fixedly connected to the upper end of the threaded column 92. A threaded seat 93 is threadedly connected to the outer side of the threaded column 92. The threaded seat 93 is rectangular. A connecting column 94 is fixedly connected to the outer side of the threaded seat 93. One end of the connecting column 94 away from the threaded seat 93 is connected to the displacement stage 5. One end of the connecting column 94 away from the threaded seat 93 is formed with a connecting groove 941. The connecting column 94 is connected to the fixing bolt 502 through the connecting groove 941.

[0039] It should be noted that the threaded column 92 is driven to rotate by the adjusting seat 921, and the threaded seat 93 drives the displacement platform 5 outside the connecting column 94 to adjust the large spacing.

[0040] The working principle of the above embodiment is:

[0041] When in use, first place the interferometer 2 and the measuring bracket 1 on the same horizontal plane, fix the frame 6 and the translation stage 5, install the reflector 7 required by the experiment on the frame 6, and place the lens 4 to be measured on the placement seat 3. When measuring, first drive the threaded column 92 to rotate through the adjustment seat 921. With the cooperation of the slot 91, the threaded seat 93 drives the translation stage 5 to adjust the large spacing through the connecting column 94. The user rotates the handle, the pitch of the threaded rod rotates, and the guide rail and the platform move together to accurately adjust the distance between the reflector 7 and the lens 4, so that the reflector 7 is located at the focal length of the lens 4. Rotate the adjusting screw to adjust the pitch of the reflector 7 until obvious light and dark stripes appear on the interferometer 2, and the transmitted wavefront of the lens 4 can be measured.

[0042] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A device for measuring the wavefront of an aspheric lens, characterized in that: The measuring bracket (1) comprises a measuring bracket (1) arranged on one side of an interferometer (2), the outer side of the measuring bracket (1) being connected to a placement seat (3), the placement seat (3) being provided with a lens (4), the side of the measuring bracket (1) being movably connected to a displacement platform (5), the outer side of the displacement platform (5) being provided with a mirror frame (6), the mirror frame (6) being provided with a reflector (7), the side of the measuring bracket (1) being provided with an inclined refractor (8), the mirror frame (6) being located above the placement seat (3), and the refractor (8) being located below the placement seat (3); An adjustment component (9) connected to the displacement platform (5) is provided in the measuring bracket (1).

2. The device for measuring the wavefront of an aspheric lens according to claim 1, characterized in that: A through hole (301) is provided on the surface of the placement seat (3), a rubber pad (302) with a placement hole is provided on the surface of the placement seat (3), the placement hole is arranged corresponding to the through hole (301), and the lens (4) is arranged on the placement hole.

3. The device for measuring the wavefront of an aspheric lens according to claim 2, characterized in that: A positioning member is provided between the placement seat (3) and the rubber pad (302), the positioning member comprising a positioning groove (303) formed on the surface of the placement seat (3), and a positioning column (304) fixedly connected to the rubber pad (302) is provided on the inner side of the positioning groove (303).

4. The device for measuring the wavefront of an aspheric lens according to claim 1, characterized in that: The lens (4) is aspherical.

5. The device for measuring the wavefront of an aspheric lens according to claim 1, characterized in that: The displacement platform (5) is a horizontal displacement platform, and a plurality of fixing holes (501) are provided on the surface of the displacement platform (5), wherein the fixing holes (501) are used to connect fixing bolts (502).

6. The device for measuring the wavefront of an aspheric lens according to claim 1, characterized in that: The mirror frame (6) is a three-dimensional optical adjustment frame, and the reflector (7) is located on the mirror frame (6).

7. The device for measuring the wavefront of an aspheric lens according to claim 1, characterized in that: The adjustment assembly (9) comprises a slot (91) formed on the surface of the measuring bracket (1); a threaded column (92) is movably connected to the inner wall of the slot (91); a threaded seat (93) is threadedly connected to the outer side of the threaded column (92); a connecting column (94) is fixedly connected to the outer side of the threaded seat (93); and an end of the connecting column (94) away from the threaded seat (93) is connected to the displacement platform (5).

8. The device for measuring the wavefront of an aspheric lens according to claim 7, characterized in that: A movable hole is formed on the top wall inside the slot hole (91), and a threaded column (92) is located inside the movable hole. The lower end of the threaded column (92) is movably connected to the inner wall of the slot hole (91) via a bearing, and the upper end of the threaded column (92) is fixedly connected to an adjustment seat (921).

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