CN-122018127-A - Aluminum-based inclined-axis large-view-field off-axis three-mirror system and rapid adjustment method

Abstract

The invention provides an aluminum-based inclined axis large-view-field off-axis three-reflecting system and a rapid adjusting method, which belong to the technical field of optical system detection, wherein the off-axis three-reflecting optical system consists of a first reflecting mirror, a second reflecting mirror, a third reflecting mirror, a substrate and a mirror frame, the substrate is provided with mounting surfaces of the first reflecting mirror and the third reflecting mirror, the space positions of the first reflector and the third reflector arranged on the substrate mounting surface meet the optical design of an off-axis three-reflector system, the surface precision requirement is met through the co-body ultra-precision machining of the first reflector and the third reflector, then the substrate is arranged on the back surface of the mirror frame, and the second reflector is arranged on the front surface of the mirror frame through the mirror frame, so that the off-axis three-reflector system is formed. Through the problem of transferring the installation and adjustment of original first speculum and third speculum to the accurate processing of first speculum and third speculum, avoid installing and adjusting first speculum and third speculum repeatedly, only adjust the space appearance of second speculum afterwards, can realize the installation and adjustment of off-axis three-mirror system.

Inventors

• HUI GANGYANG
• ZHANG XIANGMING
• ZHAO HONGJUN
• WANG MINGCHAO
• ZHANG FENG
• LIU XIN
• WANG ZHIBIN
• ZHAO JIN
• ZHANG SEN
• ZHANG BO
• ZUO XIAOZHOU
• LIU WEIGUANG

Assignees

• 西安应用光学研究所

Dates

Publication Date

20260512

Application Date

20260313

Claims (9)

1. 1. The aluminum-based inclined-axis large-view-field off-axis three-reflecting system comprises a first reflecting mirror (1), a second reflecting mirror (2) and a third reflecting mirror (3), wherein the spatial pose of the first reflecting mirror (1), the second reflecting mirror (2) and the third reflecting mirror (3) is that incident light beams are reflected by the first reflecting mirror (1), reflected by the second reflecting mirror (2) and reflected by the third reflecting mirror (3) in sequence, and a non-zero off-axis angle is formed between the optical axis of the first reflecting mirror (1) and the optical axis of the third reflecting mirror (3) so as to form an off-axis three-reflecting optical structure, and the off-axis three-reflecting system is characterized in that the first reflecting mirror (1), the second reflecting mirror (2) and the third reflecting mirror (3) are all integral reflecting mirrors, and the optical reflecting surface (2.1) and the mirror body mounting structure are integrally formed by ultra-precise machining; The first reflecting mirror (1) and the third reflecting mirror (3) are arranged on the upper surface of the substrate (4), and the installation positions of the first reflecting mirror (1) and the third reflecting mirror (3) are determined based on the space theoretical positions in optical design; the mirror frame (9) is of a structure with a hollow interior and two ends provided with openings, and is used for connecting the substrate (4) and the second reflecting mirror (2); the substrate (4) is arranged at the opening at the back of the mirror frame (9), the second reflecting mirror (2) is arranged at the opening at the front of the mirror frame (9) through the mirror frame, and the optical reflecting surface (2.1) of the second reflecting mirror (2) is opposite to the optical reflecting surface (2.1) of the first reflecting mirror (1) and the optical reflecting surface (2.1) of the third reflecting mirror (3); The mirror body outside of second speculum (2) has a plurality of mount tables that cooperate the installation with the mirror holder, have on the mount table and be used for processing second speculum (2) optical reflection face (2.1) and the location reference surface (2.2) of dress adjustment second speculum (2), location reference surface (2.2) are perpendicular with the mirror body bottom surface of second speculum (2).
2. 2. The aluminum-based oblique-axis large-view-field off-axis three-reflecting system according to claim 1, wherein the materials of the first reflecting mirror (1), the second reflecting mirror (2), the third reflecting mirror (3), the substrate (4) and the mirror frame (9) are all microcrystalline aluminum materials.
3. 3. The aluminum-based oblique-axis large-view-field off-axis three-mirror system according to claim 1 or 2, characterized in that a first mounting surface for mounting the first mirror (1) and a second mounting surface (4.1) for mounting the third mirror (3) are arranged on the substrate (4), and the positions of the first mounting surface and the second mounting surface (4.1) on the substrate (4) are set based on the spatial theoretical positions of the first mirror (1) and the third mirror (3) in the optical design.
4. 4. The aluminum-based oblique-axis large-view-field off-axis three-mirror system according to claim 3, wherein the edge of the upper surface of the base plate (4) is provided with a threaded hole for connecting with the back surface of the mirror frame (9); the outer side of the first mounting surface is provided with a plurality of threaded holes for mounting the first reflecting mirror (1); A plurality of threaded holes for installing the third reflecting mirror (3) are formed in the outer side of the second installation surface (4.1); The upper surface of the mounting table is provided with a plurality of threaded holes for connecting with the glasses frame; and a stress isolation groove (4.2) is formed in the periphery of the threaded hole.
5. 5. The aluminum-based oblique axis large-view-field off-axis three-mirror system according to claim 4, wherein the surface shape accuracy requirements of the first mounting surface, the second mounting surface (4.1) and the stress isolation groove (4.2) are 0.004mm-0.006mm; the position accuracy requirement of the positioning reference surface (2.2) is 0.004mm-0.006mm.
6. 6. A method for rapidly adjusting an aluminum-based oblique-axis large-view-field off-axis three-mirror system, which is used for adjusting the aluminum-based oblique-axis large-view-field off-axis three-mirror system according to any one of claims 1 to 5, and is characterized by comprising the following steps: S1, preparing a reference assembly and a part: The method comprises the steps of preparing a substrate (4), respectively fixing base materials of a first reflecting mirror (1) and a third reflecting mirror (3) on the substrate (4), sequentially processing optical reflecting surfaces (2.1) of the first reflecting mirror (1) and the third reflecting mirror (3) by ultra-precise turning with one clamping based on the side surface and the back surface of the substrate (4), synchronously detecting the surface type precision of the optical reflecting surfaces (2.1) of the first reflecting mirror (1) and the third reflecting mirror (3) by using a shared compensator, and processing a qualified reference component; a positioning reference surface (2.2) on the mirror body of the second reflecting mirror (2) is machined through ultra-precise turning, and an optical reflecting surface (2.1) of the second reflecting mirror (2) is machined by taking the positioning reference surface (2.2) as a reference; s2, system integration and fine tuning: The method comprises the steps of fixing a reference component on the back of a mirror frame (9), taking the normal line of the back of a substrate (4) as an optical axis reference for system adjustment, determining the space angle of a plane mirror (6) positioned in front of a first mirror (1) after autocollimation by using a collimator and the back of the substrate (4) based on the optical axis reference, installing a second mirror (2) on the front of the mirror frame (9) through a mirror frame, establishing an optical detection path based on the optical axis reference, performing wave aberration detection on the optical system by using an interferometer (5), and enabling the system wave aberration to meet a preset index by adjusting the space posture of the second mirror (2).
7. 7. The rapid adjustment method according to claim 6, wherein in the step 1, the substrate (4) is prepared by processing a first mounting surface for mounting the first reflecting mirror (1) and a second mounting surface (4.1) for mounting the second reflecting mirror (2) based on the back surface and the side surface of the substrate (4), and the positional relationship between the first mounting surface and the second mounting surface (4.1) is determined by the side surface of the substrate (4) and the inclination angle relationship between the first mounting surface and the second mounting surface (4.1) is determined by the back surface of the substrate (4) based on the theoretical pose of the first reflecting mirror (1) and the third reflecting mirror (3) in the optical design.
8. 8. The rapid tuning method according to claim 6, wherein in step2, an incident angle of the off-axis three-mirror system is determined based on the optical axis reference, the plane mirror (6) is mounted based on the incident angle, and the optical detection path detection is specifically that the laser light emitted by the interferometer (5) passes through the third mirror (3), the second mirror (2) and the first mirror (1) and then is reflected to the plane mirror (6), and the original path returns to form interference fringes and system wave aberration.
9. 9. The rapid tuning method according to claim 6, wherein in step 2, the plane mirror (6) detects the off-axis direction wave aberration formed by the first mirror (1), the second mirror (2) and the third mirror (3), and if the off-axis direction wave aberration is not symmetrical, the spatial posture of the second mirror (2) is adjusted until the off-axis direction wave aberration is symmetrical and meets the off-axis three-mirror system wave aberration index requirement, and the tuning of the off-axis three-mirror system is completed.

Description

Aluminum-based inclined-axis large-view-field off-axis three-mirror system and rapid adjustment method Technical Field The invention belongs to the technical field of optical system detection, and particularly relates to an aluminum-based inclined-axis large-view-field off-axis three-mirror system and a quick adjustment method of the aluminum-based inclined-axis large-view-field off-axis three-mirror system. Background With the increasing demand for miniaturization, light weight and high image quality of optoelectronic systems, off-axis three-mirror optical systems are becoming ideal choices. At present, the system mostly adopts the design of a high-order aspheric surface or free-form surface reflecting mirror, but the processing, detection and system adjustment difficulties of the reflecting mirror are extremely large, and the progress of the photoelectric load technology is severely restricted. The existing off-axis three-mirror system with large view field mostly adopts a main three-mirror coaxial design, and carries out precise adjustment on two mirrors and three mirrors by means of computer-aided adjustment. However, the method has the obvious defects that no perfect image point exists after the first mirror and the second mirror are combined, compensation detection is needed through a compensator, and the second mirror needs to adjust a plurality of degrees of freedom, so that the assembly and adjustment difficulty is high, the efficiency is low, and the quick integration is difficult to realize. The existing related adjustment technology also has the applicability limitation that an off-axis three-mirror system adjustment method disclosed in Chinese patent CN113126272A is required to place a theodolite between a first mirror, a second mirror and a third mirror and simultaneously carry out compensation measurement by using an interferometer, but the method is only suitable for a large off-axis three-mirror system, cannot adapt to a compact structure and is required to finish the surface compensation detection of the second mirror and the third mirror respectively, the adjustment efficiency is low, chinese patent CN111929879A discloses a small F number inclined axis large visual field off-axis three-mirror system and an adjustment method thereof, the coaxial adjustment of the second mirror and the third mirror is realized by combining the theodolite and the interferometer, but the method is only suitable for a three-mirror system which is required to be coaxially designed and is not suitable for the three-mirror system adjustment of each off-axis design. Disclosure of Invention The invention aims to solve the problems of high assembly and adjustment difficulty, low efficiency and difficult realization of rapid integration of the existing large-view-field off-axis three-mirror system, and provides an aluminum-based inclined-axis large-view-field off-axis three-mirror system and a rapid assembly and adjustment method of the aluminum-based inclined-axis large-view-field off-axis three-mirror system. In order to achieve the above purpose, the technical solution provided by the present invention is: The aluminum-based oblique-axis large-view-field off-axis three-reflecting system comprises a first reflecting mirror, a second reflecting mirror and a third reflecting mirror, wherein the spatial pose of the first reflecting mirror, the second reflecting mirror and the third reflecting mirror is that an incident light beam is reflected by the first reflecting mirror, the second reflecting mirror and the third reflecting mirror in sequence and then is reflected, and a non-zero off-axis angle is formed between the optical axis of the first reflecting mirror and the optical axis of the third reflecting mirror, so that an off-axis three-reflecting optical structure is formed; the off-axis three-mirror system further comprises a substrate and a mirror frame, the first mirror and the third mirror are arranged on the upper surface of the substrate, the installation positions of the first mirror and the third mirror are determined based on the space theory position in optical design, the optical reflection surface of the first mirror and the optical reflection surface of the third mirror arranged on the substrate are processed in a conformal mode with a standard, the mirror frame is of a structure with hollow inside and two ends provided with openings and used for connecting the substrate and the second mirror, the substrate is arranged at the opening of the back surface of the mirror frame, the second mirror is arranged at the opening of the front surface of the mirror frame through the mirror frame, the optical reflection surface of the second mirror is opposite to the optical reflection surface of the first mirror and the optical reflection surface of the third mirror, a plurality of installation tables matched with the mirror frame are arranged on the outer side of the mirror body of the second mirror, positioning