Off-axis three-mirror telescopic device and adjustment method thereof

Abstract

The invention provides an off-axis three-mirror telescopic device and an adjustment method thereof. The off-axis three-mirror telescopic device comprises an optical platform, a main frame, an off-axis mirror group, a pin sleeve and a shading plate. The main frame is of a cage type structure integrally cast and formed by metal, topological optimization treatment is carried out on the main frame, and the weight can be effectively reduced while the structural strength is guaranteed; the off-axis reflecting mirror group comprises a primary mirror assembly, a secondary mirror assembly and a three-mirror assembly, an off-axis reflecting mirror and a mirror frame in each assembly are connected in an adhesive mode, and the reflecting mirror and the mirror frame are made of the same material, so that the influence of stress on the surface shape of the reflecting mirror is eliminated. The main frame is provided with a circle of threaded through holes close to the installation positions of the secondary mirror assembly and the third mirror assembly, the adjusting screws are installed to finely adjust the radial freedom degree of the off-axis reflector, other equipment is not needed, and installation and adjustment are rapid, simple and convenient. The device is high in space utilization rate, easy to machine and assemble, good in environmental adaptability, attractive in appearance and wide in applicability.

Description

Technical Field

[0001] The invention belongs to the technical field of off-axis reflective optical systems, and in particular relates to an off-axis three-mirror telescope device and an assembly and adjustment method thereof. Background Art

[0002] Off-axis reflective optical systems have been widely used due to their wide operating band, low light energy loss, and no chromatic aberration. However, their long focal length, large field of view, and structural asymmetry have brought great difficulties to the structural design and system adjustment during the development process.

[0003] The Chinese invention patent with publication number CN105607216A discloses a large-size, high-specific-rigidity truss-type off-axis three-mirror optical system main support structure, which combines the off-axis reflectors together through the truss. Compared with the commonly used integrally cast thin-walled tube structure, this solution has the advantages of high specific rigidity and easy processing. However, since the bracket and the joint are connected by gluing, the optical system has poor environmental adaptability and is not resistant to vibration and shock. In addition, it is difficult to ensure the optical relationship between the reflectors by combining the off-axis reflectors through the bracket, which makes the system assembly difficult.

[0004] The Chinese invention patent application with publication number CN113238337A discloses a support frame structure for an off-axis three-mirror mapping camera. This solution combines the reflectors and focal planes together through a main frame integrally formed of SiC / C material, supplemented by a skin reinforcement structure to improve the overall rigidity. The main advantages of this invention are high specific rigidity, good stability, and convenience in ensuring the distance between optical components and easy installation and testing. However, because its SiC / C main frame is formed by carbon fiber preform molding technology and then reaction sintered, it is difficult to process, has high processing costs, and is difficult to make into a complex structure, which has great limitations on the overall structural design of the optical device.

[0005] Therefore, how to design a telescope device with reliable structure and simple installation and adjustment is an urgent problem to be solved. Summary of the invention

[0006] The purpose of the present invention is to solve the problems of poor environmental adaptability, inability to withstand vibration and shock, difficulty in assembly or high processing cost of existing off-axis reflective optical systems, and to provide an off-axis three-mirror telescope device and an installation and adjustment method thereof. On the one hand, the device can realize fast and simple adjustment of the off-axis reflective optical system, and on the other hand, it has the advantages of compact structure, easy processing and good environmental adaptability.

[0007] To achieve the above purpose, the technical solution provided by the present invention is:

[0008] An off-axis three-mirror telescope device comprises an optical platform, a main frame, an off-axis reflector lens group, a light shielding plate assembly and an adjusting member;

[0009] The main frame is an integrally formed topologically optimized cage structure;

[0010] The main frame is fixedly mounted on the optical platform;

[0011] The main frame is provided with a mounting through hole for mounting the off-axis reflector assembly;

[0012] The off-axis reflector assembly comprises an off-axis reflective primary mirror assembly, an off-axis reflective secondary mirror assembly and an off-axis reflective triple mirror assembly installed in corresponding mounting through holes of the main frame, wherein the off-axis reflective primary mirror assembly, the off-axis reflective secondary mirror assembly and the off-axis reflective triple mirror assembly can sequentially reflect incident light and then emit it, and the emitted light is parallel to the incident light;

[0013] A plurality of adjusting screw holes are provided on the side walls around the mounting through hole for mounting the off-axis reflective secondary mirror assembly and the off-axis reflective three-mirror assembly, and the adjusting screw holes are connected with the mounting through hole, and are used for fine-tuning the radial degree of freedom of the off-axis reflective secondary mirror assembly and the off-axis reflective three-mirror assembly by adjusting screws installed in the adjusting screw holes;

[0014] The shading plate assembly is installed on the main frame and is used to shield the off-axis reflection primary mirror assembly, the off-axis reflection secondary mirror assembly and the off-axis reflection three-mirror assembly to eliminate the influence of stray light on the imaging quality of the off-axis reflection mirror assembly.

[0015] Further, the off-axis reflection primary mirror assembly comprises a primary mirror frame and an off-axis reflection primary mirror bonded in a mounting hole on the primary mirror frame, the off-axis reflection secondary mirror assembly comprises a secondary mirror frame and an off-axis reflection secondary mirror bonded in a mounting hole on the secondary mirror frame, and the off-axis reflection triple mirror assembly comprises a triple mirror frame and an off-axis reflection triple mirror bonded in a mounting hole on the triple mirror frame;

[0016] Each off-axis reflector and the corresponding mirror frame are made of the same material, and the thickness of the glue layer between the off-axis reflector and the corresponding mirror frame is uniform.

[0017] Furthermore, it also includes a thickness-adjustable gasket; the thickness-adjustable gasket is arranged between each mirror frame and the corresponding mounting surface on the main frame, and is used to adjust the axial position and angle of each off-axis reflector by adjusting the thickness of the gasket.

[0018] Furthermore, the main mirror frame and the corresponding mounting holes on the main frame are matched with an axial hole clearance, so that the off-axis reflection main mirror assembly can rotate around the axis in the corresponding mounting holes on the main frame to adjust the position of the off-axis reflection main mirror assembly.

[0019] Further, the shading plate assembly includes a secondary mirror shading plate, a triple mirror shading plate, an upper shading plate and a side shading plate;

[0020] The secondary mirror shading plate is mounted on the main frame and close to the off-axis reflective secondary mirror assembly;

[0021] The three-mirror shading plate is mounted on the main frame and close to the off-axis reflective three-mirror assembly;

[0022] The upper shading plate is mounted on the top of the main frame;

[0023] The side shading plate is installed on the side wall of the main frame and is located between the off-axis reflection secondary mirror assembly and the off-axis reflection three-mirror assembly.

[0024] Furthermore, the secondary mirror shading plate, the three-mirror shading plate, the upper shading plate and the side shading plate are provided with screw mounting holes for fixing the secondary mirror shading plate, the three-mirror shading plate, the upper shading plate and the side shading plate to the main frame by means of screws;

[0025] The screw mounting holes are waist holes, which are used to adjust the mounting positions of the secondary mirror shading plate, the third mirror shading plate, the upper shading plate and the side shading plate on the main frame up and down.

[0026] Furthermore, it also includes a positioning component for realizing reliable positioning of the main frame on the optical platform. The positioning component includes a pin and a pin sleeve;

[0027] The bottom of the main frame has a positioning hole perpendicular to the mounting end surface of the main frame, the pin sleeve is vertically fixed in the positioning hole, the pin sleeve has a pin mounting hole, and the pin mounting hole is coaxial with the positioning hole;

[0028] The pin is vertically fixed on the top surface of the optical platform and is coaxial with the pin installation hole; the pin can pass through the pin installation hole and be plugged and matched with the pin sleeve.

[0029] Furthermore, the pin sleeve is fixed to the positioning hole of the bottom mounting end surface of the main frame by epoxy adhesive;

[0030] The pins are adhered to the top surface of the optical platform using silicone rubber.

[0031] A method for assembling and adjusting an off-axis three-mirror telescope device comprises the following steps:

[0032] Step 1: Fix the main frame on the optical platform;

[0033] Step 2: Install the off-axis reflective primary mirror assembly at a first corresponding position on the main frame;

[0034] Step 3: Install the off-axis reflection secondary mirror assembly at the second corresponding position on the main frame, measure the wave phase difference between the off-axis reflection primary mirror assembly and the off-axis reflection secondary mirror assembly, and fine-tune the position of the off-axis reflection secondary mirror assembly or the off-axis reflection primary mirror assembly until the wave phase difference between the off-axis reflection primary mirror assembly and the off-axis reflection secondary mirror assembly meets the design requirements;

[0035] Step 4: Install the off-axis reflection three-mirror assembly at the third corresponding position on the main frame, and fine-tune the position of the off-axis reflection three-mirror assembly until the wave phase difference of the off-axis reflection primary mirror assembly, the off-axis reflection secondary mirror assembly and the off-axis reflection three-mirror assembly meets the design requirements;

[0036] Step 5: Install the shading plate assembly on the main frame, and adjust the position of the shading plate assembly to block the scattered light irradiated on the off-axis reflection primary mirror assembly, the off-axis reflection secondary mirror assembly and the off-axis reflection triple mirror assembly.

[0037] An off-axis three-mirror optical imaging system comprises an imaging device and the above-mentioned off-axis three-mirror telescope device.

[0038] The advantages of the present invention are:

[0039] 1. In the off-axis three-mirror telescope device of the present invention, the primary mirror, the secondary mirror and the third mirror are connected to their respective frames by gluing, and the reflector and the frame are made of the same material; since the adhesive layer is soft in texture, on the one hand, it can effectively reduce the influence of the stress generated by the tensile deformation of the frame during installation on the surface shape of the reflector, and on the other hand, it can effectively buffer the stress generated by the deformation between the frame and the reflector when the ambient temperature changes, thereby improving the imaging quality and the temperature applicable range of the telescope device, and having good environmental applicability.

[0040] 2. The main frame of the off-axis three-mirror telescope designed in the present invention adopts an integrally formed cage structure, on which the primary mirror frame, the secondary mirror frame and the tertiary mirror frame are all mounted, which is conducive to ensuring the positional relationship between the various reflectors through processing and simplifying the installation and adjustment process; the present invention also performs topological optimization on the main frame, which effectively reduces the weight while ensuring the structural strength.

[0041] 3. In the present invention, a circle of threaded through holes is arranged on the main frame and around the mounting through holes of the off-axis reflective secondary mirror assembly and the off-axis reflective triple mirror assembly, and adjusting screws are installed in the threaded through holes. At the same time, gaskets of different thicknesses are also arranged at the mounting end faces of each off-axis reflector frame and the main frame. By adjusting the thickness of the gasket and radially adjusting the adjusting screws, fine adjustments to the degrees of freedom of the off-axis reflector can be achieved without the aid of other equipment, and installation and adjustment are quick and easy.

[0042] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0044] Figure 1 It is a schematic structural diagram of the off-axis three-transmitter telescope device of the present invention;

[0045] Figure 2 It is a schematic structural diagram of an off-axis reflection primary mirror assembly and an off-axis reflection triple mirror assembly in the present invention;

[0046] Figure 3 It is a schematic diagram of the optical path of the off-axis three-mirror optical system of the present invention;

[0047] Figure 4 It is a structural schematic diagram of the positioning method of the off-axis three-mirror telescope device of the present invention.

[0048] In the figure: 1-optical platform, 2-threaded through hole, 3-secondary mirror shading plate, 4-third mirror shading plate, 5-main frame, 6-upper shading plate, 7-side shading plate, 8-gasket, 9-secondary mirror frame, 10-secondary mirror, 11-primary mirror, 12-primary mirror frame, 13-third mirror, 14-third mirror frame, 15-processing reference surface, 16-pin, 17-pin sleeve. DETAILED DESCRIPTION

[0049] Embodiments of the present invention are described in detail below. The embodiments are exemplary and intended to be used to explain the present invention, but should not be construed as limiting the present invention.

[0050] Reference Figure 1-Figure 3An off-axis three-mirror telescope device comprises an optical platform 1, a main frame 5, an off-axis reflector lens group, a pin 16, a pin sleeve 17, and a light shielding plate assembly. The main frame 5 is a topologically optimized cage structure integrally formed of metal materials, which effectively reduces the weight while ensuring the structural strength. The off-axis reflector lens group comprises an off-axis reflective primary mirror assembly, an off-axis reflective secondary mirror assembly, and an off-axis reflective three-mirror assembly, which are respectively installed at corresponding fixed positions of the main frame, which is conducive to directly ensuring the spatial position relationship between each reflector during the main frame processing stage, simplifies the difficulty of installation and adjustment, and has a compact structure; the processing reference surface 15 during the main frame processing stage is the surface of the main frame where the off-axis reflective primary mirror assembly is installed. A circle of threaded through holes 2 is arranged on the main frame and on the side walls around the installation positions of the off-axis reflector secondary mirror assembly and the off-axis reflector tertiary mirror assembly. The threaded through holes 2 are connected with the corresponding off-axis reflector assembly installation ports on the main frame, so that the radial position of the off-axis reflector can be adjusted; and gaskets 8 of different thicknesses are also arranged between each off-axis reflector frame and the installation end face of the main frame, which are used to adjust the axial position and angle of the reflector. The gaskets 8 work together with the threaded through holes 2 to achieve fine adjustment of each degree of freedom of the off-axis reflector, without the aid of other equipment, and the installation and adjustment is quick and easy.

[0051] The off-axis reflection primary mirror assembly comprises a primary mirror frame 12 and a primary mirror 11 bonded in a mounting hole on the primary mirror frame 12, the off-axis reflection secondary mirror assembly comprises a secondary mirror frame 9 and a secondary mirror 10 bonded in a mounting hole on the secondary mirror frame 9, the off-axis reflection three-mirror assembly comprises a three-mirror frame 14 and a three-mirror 13 bonded in a mounting hole on the three-mirror frame, and the primary mirror 11, the secondary mirror 10 and the three-mirror 13 form an optical path of an off-axis three-mirror telescope. Each reflector is connected to its corresponding frame by gluing, and the glue layer between each reflector and the frame is uniform to avoid deformation of the reflective surface of the reflector due to uneven force on the reflector lens; each reflector and the corresponding frame are made of the same material, and because the glue layer is soft in texture, on the one hand, the influence of the stress generated by the tensile deformation of the frame during installation on the reflector surface shape can be effectively reduced, and on the other hand, the influence of the stress generated by the deformation between the frame and the reflector on the imaging quality when the ambient temperature changes can be effectively buffered, thereby improving the imaging quality and the temperature application range of the telescope.

[0052] The off-axis reflective primary mirror assembly, the off-axis reflective secondary mirror assembly and the off-axis reflective three-mirror assembly are all fixedly connected to the main frame 5 by front mounting screws, that is, each off-axis reflective mirror is coaxially fixed with the corresponding mounting hole on the main frame. A circle of threaded through holes 2 are arranged around the mounting positions of the off-axis reflective secondary mirror assembly and the off-axis reflective three-mirror assembly on the main frame, and the positions of the secondary mirror and the three-mirror can be fine-tuned by screwing in and out the adjusting screws. After the adjustment is completed, tighten the front mounting screws and remove the adjusting screws in the side threaded through holes 2.

[0053] Specifically, the main frame 5 and the main mirror frame 12 are matched with an axis hole clearance to achieve accurate positioning of the main mirror 11. The back of the main mirror 11 is polished to determine the incident light direction of the entire optical system. The off-axis reflective main mirror assembly can be rotated to a certain extent on the main frame 5 to achieve fine adjustment of the position of the main mirror 11, and its mounting screws are tightened after the adjustment is completed.

[0054] Specifically, the main frame 5 is topologically optimized, and the bottom and side walls of the main frame have weight-reducing grooves in a mesh structure, which can effectively reduce the weight while ensuring the structural strength of the main frame.

[0055] The shading plate assembly includes a secondary mirror shading plate 3, a third mirror shading plate 4, an upper shading plate 6 and a side shading plate 7. The secondary mirror shading plate 3 is mounted on the main frame and is close to the off-axis reflection secondary mirror assembly, and the third mirror shading plate 4 is mounted on the main frame and is close to the off-axis reflection three-mirror assembly; the upper shading plate 6 is mounted on the top of the main frame; the side shading plate 7 is arranged on the side wall of the main frame and is located between the off-axis reflection secondary mirror assembly and the off-axis reflection three-mirror assembly. A screw mounting hole is provided on each shading plate, which is used to fix the shading plate to the corresponding position of the main frame by screws. Specifically, the screw mounting hole on the shading plate is a waist-shaped hole, which is used to adjust the position of the shading plate up and down to improve the shading effect, and to eliminate the influence of stray light on the imaging quality of the off-axis reflector.

[0056] Reference Figure 3 The incident light first enters the mirror surface of the primary mirror 11, is reflected by the primary mirror 11 to the mirror surface of the secondary mirror 10, is then reflected by the secondary mirror 10 to the mirror surface of the third mirror 13, and is finally reflected by the third mirror 13, and the outgoing light is parallel to the incident light.

[0057] Reference Figure 4 The main frame 5 has a positioning hole at the bottom perpendicular to the main frame mounting end face, which is used to realize reliable positioning of the main frame 5 on the optical platform 1 through a positioning assembly. The positioning assembly includes a pin 16 and a pin sleeve 17. The pin sleeve 17 is fixed to the positioning hole of the mounting end face of the bottom of the main frame by epoxy adhesive. The pin sleeve 17 has a pin mounting hole, which is coaxial with the positioning hole on the mounting end face of the bottom of the main frame; the pin 16 is vertically adhered to the top surface of the optical platform through silicone rubber and is coaxial with the positioning hole on the mounting end face of the bottom of the main frame; the pin 16 can be plugged and matched with the pin sleeve through the pin mounting hole on the pin sleeve to realize the positioning of the main frame on the optical platform 1. After positioning, the bottom of the main frame is fixedly connected to the optical platform 1 by screws.

[0058] The installation and adjustment method of the off-axis reflective telescope device of the present invention:

[0059] First, the main frame 5 is positioned on the optical platform 1 through the cooperation of the pins 16 and the pin sleeves 17; then the main frame is fixed on the optical platform 1 by screws.

[0060] Then, install the off-axis reflection primary mirror assembly at the first corresponding position on the main frame 5 and tighten it with screws first; then install the off-axis reflection secondary mirror assembly at the second corresponding position on the main frame 5, use an interferometer to measure the wave phase difference, and fine-tune the position of the off-axis reflection secondary mirror assembly through the threaded through holes 2 and gaskets 8 arranged around it. If necessary, remove the mounting screws of the off-axis reflection primary mirror assembly, rotate the off-axis reflection primary mirror assembly, and ensure that the RMS wave phase difference between the primary mirror and the secondary mirror meets the design requirements.

[0061] Finally, install the off-axis reflection three-mirror assembly at the third corresponding position on the main frame 5, fine-tune the position of the off-axis reflection three-mirror assembly by adjusting the threaded holes 2 and gaskets 8 around it, and use an interferometer to measure the wave phase difference until the RMS wave phase difference of the primary mirror, secondary mirror, and three mirrors meets the design requirements.

[0062] After the optical path is adjusted, each shading plate is installed at the corresponding position of the main frame 5 by screws, and the position of the shading plate is adjusted up and down through the waist-shaped holes set on the shading plate to eliminate the influence of stray light on the imaging quality of the off-axis reflector.

[0063] In addition, it should be noted that the optical platform 1 also needs to have imaging components such as detectors to cooperate with the off-axis three-mirror telescope to achieve the final imaging function, and to form an off-axis three-mirror optical imaging system with the off-axis three-mirror telescope. This is not difficult for relevant practitioners in this field to understand.

[0064] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should be included in the protection scope of the present invention.

Claims

1. An off-axis three-mirror telescope device, characterized in that: It includes an optical platform, a main frame, an off-axis reflector lens assembly, a shading plate assembly and an adjusting part; The main frame is an integrally formed topologically optimized cage structure; The main frame is fixedly mounted on the optical platform; The main frame is provided with a mounting through hole for mounting the off-axis reflector assembly; The off-axis reflector assembly comprises an off-axis reflective primary mirror assembly, an off-axis reflective secondary mirror assembly and an off-axis reflective triple mirror assembly installed in corresponding mounting through holes of the main frame, wherein the off-axis reflective primary mirror assembly, the off-axis reflective secondary mirror assembly and the off-axis reflective triple mirror assembly can sequentially reflect incident light and then emit it, and the emitted light is parallel to the incident light; A plurality of adjusting screw holes are provided on the side walls around the mounting through hole for mounting the off-axis reflective secondary mirror assembly and the off-axis reflective three-mirror assembly, the adjusting screw holes are connected with the mounting through hole, and are used for fine-tuning the radial degree of freedom of the off-axis reflective secondary mirror assembly and the off-axis reflective three-mirror assembly by adjusting screws installed in the adjusting screw holes; The shading plate assembly is installed on the main frame and is used to shield the off-axis reflection primary mirror assembly, the off-axis reflection secondary mirror assembly and the off-axis reflection three-mirror assembly to eliminate the influence of stray light on the imaging quality of the off-axis reflection mirror assembly.

2. The off-axis three-mirror telescope device according to claim 1, characterized in that: The off-axis reflection primary mirror assembly comprises a primary mirror frame and an off-axis reflection primary mirror bonded in a mounting hole on the primary mirror frame; the off-axis reflection secondary mirror assembly comprises a secondary mirror frame and an off-axis reflection secondary mirror bonded in a mounting hole on the secondary mirror frame; and the off-axis reflection triple mirror assembly comprises a triple mirror frame and an off-axis reflection triple mirror bonded in a mounting hole on the triple mirror frame; Each off-axis reflector and the corresponding mirror frame are made of the same material, and the thickness of the glue layer between the off-axis reflector and the corresponding mirror frame is uniform.

3. The off-axis three-mirror telescope device according to claim 2, characterized in that: It also includes a thickness-adjustable gasket; the thickness-adjustable gasket is arranged between each mirror frame and the corresponding mounting surface on the main frame, and is used to adjust the axial position and angle of each off-axis reflector by adjusting the thickness of the gasket.

4. The off-axis three-mirror telescope device according to claim 3, characterized in that: The main mirror frame and the corresponding mounting holes on the main frame are matched with an axial hole clearance, so that the off-axis reflection main mirror assembly can rotate around the axis in the corresponding mounting holes on the main frame to adjust the position of the off-axis reflection main mirror assembly.

5. The off-axis three-mirror telescope device according to claim 4, characterized in that: The shading plate assembly includes a secondary mirror shading plate, a triple mirror shading plate, an upper shading plate and a side shading plate; The secondary mirror shading plate is mounted on the main frame and close to the off-axis reflective secondary mirror assembly; The three-mirror shading plate is mounted on the main frame and close to the off-axis reflective three-mirror assembly; The upper shading plate is mounted on the top of the main frame; The side shading plate is installed on the side wall of the main frame and is located between the off-axis reflection secondary mirror assembly and the off-axis reflection three-mirror assembly.

6. The off-axis three-mirror telescope device according to claim 5, characterized in that: The secondary mirror shading plate, the three-mirror shading plate, the upper shading plate and the side shading plate are provided with screw mounting holes for fixing the secondary mirror shading plate, the three-mirror shading plate, the upper shading plate and the side shading plate to the main frame by screws; The screw mounting holes are waist holes, which are used to adjust the mounting positions of the secondary mirror shading plate, the third mirror shading plate, the upper shading plate and the side shading plate on the main frame up and down.

7. The off-axis three-mirror telescope device according to claim 1, characterized in that: Also includes a positioning assembly; the positioning assembly includes a pin and a pin sleeve; The bottom of the main frame has a positioning hole perpendicular to the mounting end surface of the main frame, the pin sleeve is vertically fixed in the positioning hole, the pin sleeve has a pin mounting hole, and the pin mounting hole is coaxial with the positioning hole; The pin is vertically fixed on the top surface of the optical platform and is coaxial with the positioning hole on the main frame; the pin can pass through the pin installation hole and be plugged into the pin sleeve.

8. The off-axis three-mirror telescope device according to claim 7, characterized in that: The pin sleeve is fixed in the positioning hole of the mounting end surface at the bottom of the main frame by epoxy glue; The pins are adhered to the top surface of the optical platform using silicone rubber.

9. The method for assembling and adjusting an off-axis three-mirror telescope according to any one of claims 1 to 8, characterized in that: The following steps are involved: Step 1: Fix the main frame on the optical platform; Step 2: Install the off-axis reflective primary mirror assembly at a first corresponding position on the main frame; Step 3: Install the off-axis reflection secondary mirror assembly at the second corresponding position on the main frame, measure the wave phase difference between the off-axis reflection primary mirror assembly and the off-axis reflection secondary mirror assembly, and fine-tune the position of the off-axis reflection secondary mirror assembly or the off-axis reflection primary mirror assembly until the wave phase difference between the off-axis reflection primary mirror assembly and the off-axis reflection secondary mirror assembly meets the design requirements; Step 4: Install the off-axis reflection three-mirror assembly at the third corresponding position on the main frame, and fine-tune the position of the off-axis reflection three-mirror assembly until the wave phase difference of the off-axis reflection primary mirror assembly, the off-axis reflection secondary mirror assembly and the off-axis reflection three-mirror assembly meets the design requirements; Step 5: Install the shading plate assembly on the main frame, and adjust the position of the shading plate assembly to block the scattered light irradiated on the off-axis reflection primary mirror assembly, the off-axis reflection secondary mirror assembly and the off-axis reflection triple mirror assembly.

10. An off-axis three-mirror optical imaging system, characterized in that: The invention comprises an imaging device and an off-axis three-mirror telescope device as described in any one of claims 1 to 8.

Images