Micro-stress support structure for optical elements with multi-degree-of-freedom adjustment and its alignment method

Abstract

The present invention provides a multi-degree-of-freedom adjustment optical element micro-stress support structure and its installation and adjustment method, which are used to solve the technical problems of the existing optical element posture adjustment method, which requires repeated disassembly and assembly of optical elements and grinding and trimming pads, resulting in cumbersome processes, long time consumption, and inability to achieve continuous adjustment to determine the best imaging position. The micro-stress support structure of the present invention includes an adjustment frame, an adapter frame, a fixed frame, and multiple groups of connection adjustment mechanisms; the adjustment frame, the adapter frame, and the fixed frame are coaxially connected in sequence; the adapter frame is fixedly connected to the end face of the adjustment frame; the connection adjustment mechanism includes a fine-tooth adjustment rod, a disc spring assembly, and a spherical trimming pad; one end of the fine-tooth adjustment rod passes through the through hole of the spherical trimming pad, the first through hole on the fixed frame, and the inner hole of the disc spring assembly in sequence, and is connected to the first threaded hole on the adapter frame, so that the multi-degree-of-freedom adjustment of the surface shape of the optical element to be adjusted is achieved on the basis of ensuring the surface shape accuracy.

Description

Technical Field

[0001] The invention relates to the position and posture adjustment of an optical element, and in particular to a multi-degree-of-freedom-adjustable optical element micro-stress support structure and an assembly and adjustment method thereof. Background Art

[0002] There are usually certain errors in the processing and assembly of optical parts and structural parts. During the development of optical instruments, it is necessary to adjust the spatial position and posture of some or all optical elements to achieve higher performance imaging. The most commonly used adjustment method is to set one or more layers of trimming pads. For example, in the Chinese patent CN112013954A, an offner hyperspectral imaging system based on a curved prism, the position and posture of the optical element are adjusted by trimming the thickness of the trimming pad. The disadvantage of this method is that the process is cumbersome and time-consuming, and it requires repeated disassembly and assembly of optical elements and grinding of trimming pads, and it is impossible to achieve continuous adjustment to determine the optimal imaging position. Summary of the invention

[0003] The purpose of the present invention is to solve the technical problems of the existing method for adjusting the position of optical elements, such as the need to repeatedly disassemble and assemble optical elements and grind and trim pads, which leads to complicated processes, long time consumption, and inability to achieve continuous adjustment to determine the optimal imaging position, and to provide a multi-degree-of-freedom adjustable optical element micro-stress support structure and its assembly and adjustment method.

[0004] The technical solution of the present invention is:

[0005] A multi-degree-of-freedom adjustable optical element micro-stress support structure, which is special in that it includes an adjustment frame, a transfer frame, a fixed frame and multiple sets of connection adjustment mechanisms;

[0006] The adjusting frame, the transfer frame and the fixed frame are coaxially connected in sequence;

[0007] The adjusting lens frame is used to install the optical element to be adjusted; the adapter lens frame is fixedly connected to the end surface of one end of the adjusting lens frame;

[0008] The connection adjustment mechanism includes a fine-thread adjustment rod, a disc spring assembly and a spherical trimming pad;

[0009] The spherical trimming pad is a cylinder, and one end of the cylinder is set as a spherical surface; the spherical trimming pad is provided with an axially penetrating through hole; the disc spring assembly is provided with an axially penetrating inner hole;

[0010] A plurality of first threaded holes are circumferentially formed on the end surface of the adapter frame;

[0011] On the end face of the fixed spectacle frame, a plurality of first through holes are provided at positions corresponding to the plurality of first threaded holes, and the end of the through hole away from the adapter spectacle frame is provided with a spherical concave surface, which is adapted to the surface of the spherical trimming pad for installing the spherical trimming pad;

[0012] One end of the fine-thread adjusting rod sequentially passes through the through hole of the spherical trimming pad, the first through hole on the fixed spectacle frame and the inner hole of the disc spring assembly, and is connected to the corresponding first threaded hole on the adapter spectacle frame.

[0013] Furthermore, it further includes a locking set screw;

[0014] On the cylindrical side wall of the spherical trimming pad, a second threaded hole adapted to the locking set screw is provided;

[0015] The locking set screw fastens the fine-thread adjusting rod through the second threaded hole.

[0016] Furthermore, a gap of 0.1 mm - 0.15 mm is reserved between the inner wall of the adjusting spectacle frame and the outer wall of the optical element to be adjusted;

[0017] On the side wall of the adjusting spectacle frame, a plurality of third threaded holes are provided for adjusting the coaxiality of the optical element to be adjusted and the adjusting spectacle frame through the third threaded holes.

[0018] Furthermore, it further includes a plurality of fastening screws;

[0019] A plurality of fourth threaded holes are evenly distributed in a circumferential manner on the adjusting spectacle frame;

[0020] At positions corresponding to the plurality of fourth threaded holes on the adapter spectacle frame, a plurality of second through holes are provided;

[0021] The plurality of fastening screws pass through the second through holes and are connected to the fourth threaded holes, and the coaxial connection between the adapter spectacle frame and the adjusting spectacle frame is realized by adjusting the relative positions of the fastening screws and the second through holes.

[0022] Furthermore, it further includes a retaining ring;

[0023] The retaining ring presses the optical element to be adjusted tightly in the adjusting spectacle frame through the other end of the adjusting spectacle frame.

[0024] Furthermore, there are three sets of connection and adjustment mechanisms. The design of the three sets of connection and adjustment mechanisms makes full use of the principle that three points determine a plane, so that the system will not have overconstraint, and any two of the three points can realize the adjustment of one degree of freedom, which is convenient for the adjustment of the pitching, azimuth and rotation angles of the lens group, and the adjustment is simple.

[0025] Based on the above-mentioned micro-stress support structure for an optical element with multi-degree-of-freedom adjustment, the present invention also provides an alignment method for the micro-stress support structure of an optical element with multi-degree-of-freedom adjustment, which is characterized in that it includes the following steps:

[0026] 1】Coaxially install the optical element to be adjusted in the adjustment frame;

[0027] 2】Coaxially and fixedly install the adapter frame on the end face at one end of the adjustment frame;

[0028] 3】Insert one end of the fine-thread adjustment rod successively through the through-hole of the spherical trimming pad, the first through-hole of the fixed frame, and the inner hole of the disc spring assembly, and then connect it to the corresponding first threaded hole on the adapter frame;

[0029] 4】By adjusting the relative position of the fine-thread adjustment rod and the first through-hole, the coaxial setting of the fixed frame and the adjustment frame is realized, and further the coaxial setting of the fixed frame and the optical element to be adjusted is realized;

[0030] 5】Connect the fixed frame to the external optical path, and according to the imaging quality, adjust the multiple fine-thread adjustment rods to realize the translation of the optical element to be adjusted along the Z direction and the rotation around the X axis and Y axis, and complete the multi-degree-of-freedom adjustment of the surface shape of the optical element to be adjusted.

[0031] Further, after step 5】, it also includes:

[0032] After completing the surface shape adjustment of the optical element to be adjusted, make the locking set screw apply a pre-tightening force to the fine-thread adjustment rod through the second threaded hole to fasten it.

[0033] Further, step 1】is specifically:

[0034] 1.1】Install the optical element to be adjusted in the adjustment frame, and preliminarily fix the optical element to be adjusted in the adjustment frame through the retaining ring;

[0035] 1.2】Through the uniformly distributed third threaded holes on the side wall of the adjustment frame, realize the coaxial installation of the optical element to be adjusted and the adjustment frame; and after the installation is completed, inject silicone rubber to realize the micro-stress fixation of the optical element to be adjusted in the adjustment frame.

[0036] Further, step 2】is specifically:

[0037] Make multiple fastening screws respectively pass through the corresponding second through-holes on the adapter frame and connect to the corresponding fourth threaded holes on the adjustment frame, and realize the coaxial connection of the adapter frame and the adjustment frame by adjusting the relative position of the fastening screws and the second through-holes.

[0038] The beneficial effects of the present invention compared with the prior art are:

[0039] 1. A micro-stress support structure for an optical element with multi-degree-of-freedom adjustment provided by the present invention, through the threaded connection of a fine-thread adjusting rod and the pre-tightening of a disc spring assembly, provides the required connection support force and pre-tightening force while fixing the optical element to be adjusted. The overall structure is simple and highly feasible. On the basis of ensuring the surface shape accuracy, it realizes the multi-degree-of-freedom adjustment of the pose of the optical element to be adjusted, and can be applied to the multi-degree-of-freedom micro-stress support of optical elements such as mirrors and transmissive gratings.

[0040] 2. A micro-stress support structure for an optical element with multi-degree-of-freedom adjustment provided by the present invention, by designing an adapter frame between the adjustment frame and the fixed frame, avoids the adjustment force applied during adjustment being directly applied to the adjustment frame on which the optical element to be adjusted is installed, effectively ensuring the stability of the surface shape of the optical element to be adjusted during the adjustment process.

[0041] 3. A micro-stress support structure for an optical element with multi-degree-of-freedom adjustment provided by the present invention, by adding a spherical trimming pad between the fine-thread adjusting rod and the fixed frame, ensures the reliability of the connection between the two when adjusting the position of the optical element to be adjusted. At the same time, the fine-thread adjusting rod is locked by a locking set screw, ensuring the stability and reliability after the position adjustment of the optical element to be adjusted is completed.

[0042] 4. An assembly and adjustment method for a micro-stress support structure of an optical element with multi-degree-of-freedom adjustment provided by the present invention, using the step-by-step connection method, improves the consistency of the relative theoretical positions of the optical element to be adjusted and each layer of fixed structures, and reduces the assembly and adjustment difficulty of system integration. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 is a cross-sectional view of an embodiment of a micro-stress support structure for an optical element with multi-degree-of-freedom adjustment of the present invention;

[0044] Figure 2 is a schematic structural diagram of an embodiment of the present invention;

[0045] Figure 3 is a schematic structural diagram of the spherical trimming pad in an embodiment of the present invention.

[0046] The specific reference numerals are as follows:

[0047] 1 - adjustment frame; 2 - retaining ring; 3 - adapter frame; 4 - fastening screw; 5 - fixed frame;

[0048] 6 - fine-thread adjusting rod; 7 - disc spring assembly; 8 - spherical trimming pad; 9 - locking set screw; 10 - optical element to be adjusted; 11 - through hole; 12 - second threaded hole. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0049] In order to make the advantages and features of the present invention more clear, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0050] like Figure 1 , Figure 2 As shown, a micro-stress support structure for optical elements with multi-degree-of-freedom adjustment includes an adjustment frame 1, an adapter frame 3, a fixed frame 5, three sets of connection adjustment mechanisms and corresponding three locking top screws 9. The adjustment frame 1 is used to install the optical element 10 to be adjusted, and a gap of 0.1mm-0.15mm is reserved between the inner wall of the adjustment frame 1 and the outer wall of the optical element 10 to be adjusted; a plurality of third threaded holes are provided on the side wall of the adjustment frame 1, which are used to adjust the coaxiality of the optical element 10 to be adjusted and the adjustment frame 1 through the third threaded holes after preliminary installation. The present invention is also provided with a pressing ring 2, which presses the optical element 10 to be adjusted in the adjustment frame 1 through the other end of the adjustment frame 1, so as to achieve reliable fixation of the optical element 10 to be adjusted. The adjustment frame 1, the adapter frame 3, and the fixed frame 5 are coaxially connected in sequence. Among them, six fourth threaded holes are evenly distributed on the circumference of the adjustment frame 1, and six second through holes are opened on the adapter frame 3 at positions corresponding to the multiple fourth threaded holes; six fastening screws 4 are connected to the second through holes through the corresponding fourth threaded holes, and the coaxial connection between the adapter frame 3 and the adjustment frame 1 is achieved by adjusting the relative positions of the fastening screws 4 and the second through holes. The setting of the adapter frame 3 in the present invention avoids the adjustment force directly acting on the adjustment frame 1 when adjusting the posture of the optical element 10 to be adjusted, which is used to reduce the influence of the deformation of the adjustment frame 1 on the surface shape of the optical element 10 to be adjusted in the frame, and ensure the surface shape accuracy of the optical element 10 to be adjusted. The fixed frame 5 is connected to the adapter frame 3 through three sets of connection and adjustment mechanisms. Specifically, the connection and adjustment mechanism includes a fine-tooth adjustment rod 6, a disc spring assembly 7 and a spherical trimming pad 8. As Figure 3As shown, the spherical trimming pad 8 is a cylinder, and one end of the cylinder is provided with a spherical surface. An axially penetrating through-hole 11 is provided on the spherical trimming pad 8; the disc spring assembly 7 includes three disc springs stacked in sequence, and an axially penetrating inner hole is provided on the disc spring assembly 7. First threaded holes adapted to the threaded rods of the three fine-thread adjusting rods 6 are circumferentially and uniformly provided on the end surface of the adapter frame 3; three first through-holes are provided at positions corresponding to the three first threaded holes on the end surface of the fixed frame 5. The ends of the three first through-holes away from the adapter frame 3 are provided with spherical concave surfaces for adapting to the surface of the above-mentioned spherical trimming pad 8. One end of the threaded rod of the fine-thread adjusting rod 6 sequentially passes through the through-hole 11 of the spherical trimming pad 8, the first through-hole on the fixed frame 5, and the inner hole of the disc spring assembly 7, and is connected to the corresponding first threaded hole on the adapter frame 3. Among them, the fine-thread adjusting rod 6 is used to provide the connection support force between the adapter frame 3 and the fixed frame 5, the disc spring assembly 7 is used to provide the pre-tightening force for the connection between the adapter frame 3 and the fixed frame 5, and the spherical trimming pad 8 is used to ensure that after the positions of the two are adjusted, the fine-thread adjusting rod 6 can still be reliably pressed on the fixed frame 5. After the fixed frame 5 is connected to the adapter frame 3, by rotating and adjusting the fine-thread adjusting rod 6, the optical element 10 to be adjusted can be translated along the Figure 1 Z direction shown and rotated around the X-axis and Y-axis, completing the multi-degree-of-freedom adjustment of the surface shape of the optical element 10 to be adjusted. At the same time, a second threaded hole 12 adapted to the locking set screw 9 is provided on the side wall of the spherical trimming pad 8. After the surface shape adjustment of the optical element 10 to be adjusted is completed, the locking set screw 9 applies a pre-tightening force to the fine-thread adjusting rod 6 through the second threaded hole 12 for fastening. At the same time, thread locking glue can also be applied to the second threaded hole 12 to ensure the stability of the relative position between the adapter frame 3 and the fixed frame 5, and further ensure the stability of the relative position between the optical element 10 to be adjusted and the fixed frame 5.

[0051] Based on the above optical element micro-stress support structure with multi-degree-of-freedom adjustment, the present invention also provides an alignment method for the optical element micro-stress support structure with multi-degree-of-freedom adjustment, including the following steps:

[0052] 1. Install the optical element 10 to be adjusted

[0053] 1.1 Install the optical element 10 to be adjusted in the adjustment frame 1, and preliminarily fix the optical element 10 to be adjusted in the adjustment frame 1 through the retaining ring 2;

[0054] 1.2 Through the uniformly distributed third threaded holes on the side wall of the adjustment frame 1, realize the coaxial installation of the optical element 10 to be adjusted and the adjustment frame 1; and after the installation is completed, inject silicone rubber to realize the micro-stress fixation of the optical element 10 to be adjusted in the adjustment frame 1.

[0055] 2】 Pass the six fastening screws 4 through the corresponding second through holes on the adapter frame 3 and connect them to the corresponding fourth threaded holes on the adjustment frame 1 respectively, and realize the coaxial connection of the adapter frame 3 and the adjustment frame 1 by adjusting the relative positions of the fastening screws 4 and the second through holes.

[0056] 3】 Pass one end of the threaded rod of the fine-thread adjustment rod 6 through the through hole 11 of the spherical trimming pad 8, the first through hole of the fixed frame 5 and the inner hole of the disc spring assembly 7 in sequence, and then connect it to the corresponding first threaded hole on the adapter frame 3;

[0057] 4】 By adjusting the relative positions of the fine-thread adjustment rod 6 and the first through hole, the coaxial setting of the fixed frame 5 and the adjustment frame 1 is realized, and further the coaxial setting of the fixed frame 5 and the optical element 10 to be adjusted is realized.

[0058] 5】 Connect the fixed frame 5 to the external optical path, and according to the imaging quality, realize the translation of the optical element 10 to be adjusted along the Z direction and the rotation around the X axis and the Y axis by adjusting the three fine-thread adjustment rods 6, and complete the multi-degree-of-freedom adjustment of the surface shape of the optical element 10 to be adjusted.

[0059] As described above, it is only used to illustrate the technical solution of the present invention, rather than to limit it. For those of ordinary professional skills in the art, the specific technical solution recorded in the above embodiments can be modified, or some of the technical features can be equivalently replaced, and these modifications or replacements do not make the essence of the corresponding technical solution deviate from the scope of the technical solution protected by the present invention.

Claims

1. A micro-stress support structure for an optical element with multi-degree-of-freedom adjustment, characterized in that: It includes an adjustment frame (1), a transition frame (3), a fixed frame (5), three groups of connection and adjustment mechanisms, and a locking set screw (9); The adjustment frame (1), the transition frame (3), and the fixed frame (5) are coaxially connected in sequence; The adjustment frame (1) is used to install the optical element to be adjusted (10); the transition frame (3) is fixedly connected to the end face at one end of the adjustment frame (1); The connection and adjustment mechanism includes a fine-thread adjustment rod (6), a disc spring assembly (7), and a spherical trimming pad (8); The spherical trimming pad (8) is a cylinder, and one end of the cylinder is set as a spherical surface; a through hole (11) axially penetrating is provided on the spherical trimming pad (8); an inner hole axially penetrating is provided on the disc spring assembly (7); A plurality of first threaded holes are circumferentially provided on the end face of the transition frame (3); At positions corresponding to the plurality of first threaded holes on the end face of the fixed frame (5), a plurality of first through holes are provided, and the end of the through hole away from the transition frame (3) is set as a spherical concave surface, and the spherical concave surface is adapted to the surface of the spherical trimming pad (8); One end of the fine-thread adjustment rod (6) sequentially passes through the through hole (11) of the spherical trimming pad (8), the first through hole on the fixed frame (5), and the inner hole of the disc spring assembly (7), and is connected to the corresponding first threaded hole on the transition frame (3); A second threaded hole (12) adapted to the locking set screw (9) is provided on the side wall of the cylinder of the spherical trimming pad (8); The locking set screw (9) fastens the fine-thread adjustment rod (6) through the second threaded hole (12).

2. The micro-stress support structure for an optical element with multi-degree-of-freedom adjustment according to claim 1, characterized in that: A gap of 0.1 mm - 0.15 mm is reserved between the inner wall of the adjustment frame (1) and the outer wall of the optical element to be adjusted (10); A plurality of third threaded holes are provided on the side wall of the adjustment frame (1) for adjusting the coaxiality of the optical element to be adjusted (10) and the adjustment frame (1) through the third threaded holes.

3. The micro-stress support structure for an optical element with multi-degree-of-freedom adjustment according to claim 2, characterized in that: It further includes a plurality of fastening screws (4); A plurality of fourth threaded holes are evenly distributed in a circle on the adjustment frame (1); A plurality of second through holes are provided at positions corresponding to the plurality of fourth threaded holes on the transition frame (3); The plurality of fastening screws (4) pass through the second through holes and are connected to the fourth threaded holes, and the coaxial connection between the transition frame (3) and the adjustment frame (1) is realized by adjusting the relative positions of the fastening screws (4) and the second through holes.

4. The micro-stress support structure for an optical element with multi-degree-of-freedom adjustment according to claim 3, characterized in that: It further includes a retaining ring (2); The retaining ring (2) presses the optical element to be adjusted (10) into the adjustment frame (1) through the other end of the adjustment frame (1).

5. An alignment method for the micro-stress support structure of a mirror with multi-degree-of-freedom adjustment according to any one of claims 1-4, characterized in that, It includes the following steps: 1】Coaxially install the optical element to be adjusted (10) in the adjustment frame (1); 2】Coaxially and fixedly install the adapter frame (3) on the end face at one end of the adjustment frame (1); 3】Insert one end of the fine-thread adjustment rod (6) successively through the through-hole (11) of the spherical trimming pad (8), the first through-hole of the fixed frame (5), and the inner hole of the disc spring assembly (7), and then connect it to the corresponding first threaded hole on the adapter frame (3); 4】By adjusting the relative position of the fine-thread adjustment rod (6) and the first through-hole, the fixed frame (5) is coaxially arranged with the adjustment frame (1), and further, the fixed frame (5) is coaxially arranged with the optical element to be adjusted (10); 5】Connect the fixed frame (5) to the external optical path. According to the imaging quality, translate the optical element to be adjusted (10) along the Z-axis and rotate it around the X-axis and Y-axis by adjusting multiple fine-thread adjustment rods (6) to complete the multi-degree-of-freedom adjustment of the surface shape of the optical element to be adjusted (10).

6. The alignment method of the micro-stress support structure of the optical element with multi-degree-of-freedom adjustment according to claim 5, characterized in that: After step 5】, it further includes: After completing the surface shape adjustment of the optical element to be adjusted (10), make the locking set screw (9) apply a pre-tightening force to the fine-thread adjustment rod (6) through the second threaded hole (12) to fasten it.

7. The alignment method of the micro-stress support structure of the multi-degree-of-freedom adjustable optical element according to claim 6, characterized in that Step 1】Specifically: 1.1】Install the optical element to be adjusted (10) in the adjustment frame (1), and preliminarily fix the optical element to be adjusted (10) in the adjustment frame (1) through the retaining ring (2); 1.2】Through the uniformly distributed third threaded holes on the side wall of the adjustment frame (1), realize the coaxial installation of the optical element to be adjusted (10) and the adjustment frame (1); and after the installation is completed, inject silicone rubber to realize the micro-stress fixation of the optical element to be adjusted (10) in the adjustment frame (1).

8. The alignment method of the micro-stress support structure of the optical element with multi-degree-of-freedom adjustment according to claim 7, characterized in that Step 2】Specifically: Make multiple fastening screws (4) respectively pass through the corresponding second through-holes on the adapter frame (3) and connect to the corresponding fourth threaded holes on the adjustment frame (1), and realize the coaxial connection of the adapter frame (3) and the adjustment frame (1) by adjusting the relative position of the fastening screws (4) and the second through-holes.

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