Adjusting device for off-axis free-form spectrometer system based on computer holographic device

Abstract

The present application relates to the technical field of optical machine adjustment, and discloses an adjusting device of off-axis free-form surface spectrometer system based on a computer holographic device, which comprises an adjusting device, and the adjusting device is composed of an interferometer, an attenuating sheet, a computer holographic device, a spectrometer module, a six-dimensional adjusting frame, a metal cushion block and an air floating platform, wherein the spectrometer module is composed of a spectrometer frame, a first mirror frame, a grating mirror frame, a third mirror frame, a first mirror, a grating, a third mirror, a second mirror and a second mirror frame. The present application sets the alignment holographic area, the main holographic area and the reference holographic area of two mirrors and a grating together on a computer holographic device, so that the adjustment of the off-axis free-form surface spectrometer system can be efficiently completed by using one computer holographic device, the adjustment degree of freedom is reduced, the adjustment difficulty is lowered, the auxiliary tooling is simplified, and the cost and time are saved.

Description

Technical Field

[0001] This invention relates to the field of optomechanical assembly and calibration technology, specifically to assembly and calibration equipment for an off-axis freeform surface spectrometer system based on computational holographic devices. Background Technology

[0002] With the development of space technology, there is a need for optical systems with higher imaging quality, wider swaths, larger fields of view, and more precise structures. Off-axis three-lens reflex systems not only have higher imaging quality but also resolve the contradiction between a large field of view and high resolution. However, the overall structure is relatively large. The use of freeform surfaces can improve imaging quality and expand the field of view while optimizing the structure of the optical system. This makes the originally complex and bulky system simple and lightweight in order to meet the requirements of optical design. However, the constraints of multiple degrees of freedom in the assembly and adjustment process greatly increase the difficulty of assembly, adjustment, and inspection, thus restricting the use of freeform surfaces.

[0003] Computer-Generated Holograms (CGHs) are a high-precision method for detecting freeform surfaces. They are simple in structure and have auxiliary adjustment functions. In actual aspheric surface detection, CGHs mainly consist of three parts: first, the alignment hologram of the auxiliary positioning area; second, the master hologram of the aspheric surface region to be detected; and third, the reference hologram for positioning the aspheric mirror. The master hologram is located in the central region of the CGH. The detection beam emitted by the interferometer, after exiting through the standard lens, becomes a standard spherical wave. After passing through the master holographic region of the CGH, the light is incident perpendicularly to the aspheric surface. The reflected light contains the surface shape information of the test object. Returning to the CGH, it becomes a spherical wave again and interferes with the reference beam of the interferometer. The resulting surface shape data is the residual between the measured surface shape and the theoretical surface shape.

[0004] Traditional CGHs only contain one main holographic region, one alignment holographic region, and one reference holographic region group, and can only perform surface shape detection for one mirror. Combining multiple main holographic regions, alignment holographic regions, and reference holographic region groups into one CGH can reduce the degree of freedom in assembly and adjustment, greatly reduce the difficulty of assembly and adjustment, and save time and costs. Summary of the Invention

[0005] The purpose of this invention is to provide an assembly and adjustment device for an off-axis freeform surface spectrometer system based on computational holographic devices.

[0006] To achieve the above objectives, the present invention provides the following technical solution: an assembly and adjustment device for an off-axis freeform surface spectrometer system based on computational holographic devices, comprising an interferometer, an attenuator, a computational holographic device, a spectrometer module, a six-dimensional adjustment frame, metal pads, and an air-bearing platform. The spectrometer module comprises a spectrometer frame, a first reflecting mirror frame, a grating mirror frame, a third reflecting mirror frame, a first reflecting mirror, a grating, a third reflecting mirror, a second reflecting mirror, a second reflecting mirror frame, and a standard spherical mirror. Assembly and adjustment are completed through the following steps:

[0007] Step 1: Using a six-dimensional adjustment frame and metal pads, install the interferometer, attenuator CGH, and spectrometer module on the air-floating platform, and initially adjust the optical axis to the same height by measuring with a ruler.

[0008] Step two: The light emitted by the interferometer is incident on the first aligned holographic region of the CGH, and after reflection, it returns to the interferometer, forming interference fringes. The six-dimensional adjustment frame is adjusted so that the first aligned holographic region has zero fringes, and the six-dimensional adjustment frame is fixed. The light emitted by the interferometer is incident on the first set of reference holographic regions, producing four image points. The first reflecting mirror frame is adjusted so that the four image points coincide with the four marked points on the first reflecting mirror frame, and the position of the first reflecting mirror is initially determined. The light emitted by the interferometer passes through the attenuator and is incident on the first main holographic region, and then on the first reflecting mirror of the spectrometer. The light is reflected back to the interferometer, forming interference fringes. The first reflecting mirror frame is adjusted so that the interference fringes have zero fringes, and the position of the first reflecting mirror is determined.

[0009] Step 3: The light emitted by the interferometer is incident on the second alignment holographic region of the CGH. After reflection, it returns to the interferometer, forming interference fringes. The six-dimensional adjustment frame is adjusted so that the second alignment holographic region has zero fringes, and the six-dimensional adjustment frame is fixed. The light emitted by the interferometer is incident on the second set of reference holographic regions, producing four image points. The grating frame is adjusted so that the four image points coincide with the four marked points on the grating frame, and the grating position is initially determined. The light emitted by the interferometer passes through the attenuator and is incident on the second main holographic region, and then on the spectrometer grating. The light is reflected back to the interferometer, forming interference fringes. The light emitted by the interferometer passes through the attenuator and is incident on the third main holographic region, and then on the spectrometer grating. The light is reflected back to the interferometer, forming interference fringes. The grating frame is adjusted so that the interference fringes in both main holographic regions are zero fringes, and the position of the grating is determined.

[0010] Step 4: The light emitted by the interferometer is incident on the third alignment holographic region of the CGH. After reflection, it returns to the interferometer, forming interference fringes. The six-dimensional adjustment frame is adjusted so that the third alignment holographic region has zero fringes, and the six-dimensional adjustment frame is fixed. The light emitted by the interferometer is incident on the third set of reference holographic regions, producing four image points. The third reflecting mirror frame is adjusted so that the four image points coincide with the marked points on the third reflecting mirror frame, and the position of the third reflecting mirror is initially determined. The light emitted by the interferometer passes through the attenuator and is incident on the fourth principal holographic region, and then on the third reflecting mirror of the spectrometer. The light is reflected back to the interferometer, forming interference fringes. The third reflecting mirror frame is adjusted so that the interference fringes have zero fringes, and the position of the third reflecting mirror is determined.

[0011] Step 5: Remove the computational holographic device and install the second reflector onto the spectrometer module frame. Based on the standard spherical mirror optical path self-return principle, adjust the orientation of the second reflector frame according to the theoretical wave aberration to ensure that the wave aberration of the spectrometer system meets the requirements, thus completing the installation and adjustment of the second reflector.

[0012] Preferably, the computational holographic device comprises four main holographic regions, three alignment holographic regions, and three sets of reference holographic regions. Specifically, the first main holographic region corresponds to the first mirror, the second main holographic region corresponds to the grating order, the third main holographic region corresponds to the grating+ order, and the fourth main holographic region corresponds to the third mirror. The first alignment holographic region is used to determine the relative position of the interferometer and the CGH, and is used to adjust the attitude of the first mirror. The second alignment holographic region is used to determine the relative position of the interferometer and the CGH, and is used to adjust the attitude of the grating using the second and third main holographic regions. The third alignment holographic region is used to determine the relative position of the interferometer and the CGH, and is used to adjust the attitude of the third mirror using the fourth main holographic region. The first set of reference holographic regions corresponds to the coarse adjustment position of the first mirror, the second set of reference holographic regions corresponds to the coarse adjustment position of the grating, and the third set of reference holographic regions corresponds to the coarse adjustment position of the third mirror.

[0013] Preferably, after blocking other diffraction regions, the light emitted by the interferometer, incident on the first aligned holographic region, returns to the interferometer and forms interference fringes. Adjusting the six-dimensional adjustment frame, when the fringes approach zero, determines the relative position of the interferometer and the CGH. After blocking other diffraction regions, the light emitted by the interferometer passes through the first set of reference holographic regions and is incident on the first reflecting mirror, forming image points at four positions (up, down, left, and right) on the surface of the first reflecting mirror. Adjusting the first reflecting mirror frame so that the four image points coincide with the four marked points on the first reflecting mirror frame, and after blocking other diffraction regions, the light emitted by the interferometer passes through the attenuator and the first main holographic region... The light emitted from the first mirror is reflected back to the interferometer through the first principal holographic region, forming interference fringes. The first mirror frame is finely adjusted until the interference fringes approach zero, completing the positioning of the first mirror. With the CGH and spectrometer module stationary, other diffraction regions are blocked. The light from the interferometer is then incident on the second aligned holographic region and returns to the interferometer, forming interference fringes. The six-dimensional adjustment frame is adjusted until the fringes approach zero, determining the relative position of the interferometer and CGH. The light emitted from the interferometer passes through the attenuator and the second set of reference holographic regions onto the grating, forming four image points on the grating surface (top, bottom, left, and right). The grating frame is then adjusted. The four image points are aligned with the four marked points on the edge of the grating frame. The light emitted by the interferometer passes through the attenuator and the second principal holographic region corresponding to the order, then enters the grating. After reflection, it returns to the interferometer to form interference fringes. The light emitted by the interferometer passes through the attenuator and the third principal holographic region corresponding to the + order, then enters the grating. After reflection, it returns to the interferometer to form interference fringes. The grating frame is adjusted until the fringes of both interference orders approach zero, thus completing the grating positioning. Other diffraction regions are blocked, and the light from the interferometer enters the third aligned holographic region and returns to the interferometer to form interference fringes. The six-dimensional adjustment frame is adjusted until the fringes approach zero. At zero, the relative position of the interferometer and CGH can be determined, blocking other diffraction areas. The light emitted by the interferometer is incident on the third mirror through the third reference holographic region, forming four image points on the surface of the third mirror. The frame of the third mirror is adjusted so that the four image points coincide with the four marked points on the frame of the third mirror, blocking other diffraction areas. The light emitted by the interferometer passes through the attenuator and the fourth principal holographic region and is incident on the third mirror. The reflected light returns to the interferometer through the fourth principal holographic region to form interference fringes. The frame of the third mirror is finely adjusted. When the interference fringes approach the zero fringe, the positioning of the third mirror is completed.

[0014] Preferably, after the first reflecting mirror, grating, and third reflecting mirror of the spectrometer module are positioned, the CGH is removed, and the second reflecting mirror frame, which is fixedly sealed with the second reflecting mirror, is installed on the spectrometer module. The standard spherical mirror is installed at the object-side position of the off-axis freeform surface spectrometer system. The interferometer focus is moved to the image plane position of the off-axis freeform surface spectrometer system. The measurement beam is emitted by the interferometer, passes through the spectrometer system, and is incident on the standard spherical mirror. The reflected light returns to the interferometer to form interference fringes. The second reflecting mirror frame is adjusted according to the theoretical wave aberration so that the wave aberration of the spectrometer system meets the theoretical requirements, thus completing the installation and adjustment of the second reflecting mirror.

[0015] This invention provides an assembly and adjustment device for an off-axis freeform surface spectrometer system based on computational holography. This assembly and adjustment device for the off-axis freeform surface spectrometer system based on computational holography has the following beneficial effects:

[0016] This invention integrates the alignment holographic region, main holographic region, and reference holographic region of two mirrors and a grating onto a single computational holographic device. This allows for efficient assembly and adjustment of an off-axis freeform surface spectrometer system using a single computational holographic device, reducing the degrees of freedom in assembly and adjustment, lowering the difficulty of assembly and adjustment, simplifying auxiliary tooling, and saving costs and time. Attached Figure Description

[0017] Figure 1 This is a top view of the off-axis freeform surface spectrometer system based on computational holography as described in this invention.

[0018] Figure 2 This is a schematic diagram of the side chamber structure of the off-axis freeform surface spectrometer system based on computational holography devices described in this invention;

[0019] Figure 3 This is a schematic diagram of the CGH-containing region described in this invention.

[0020] Figure 4 This is a schematic diagram of the spectrometer system described in this invention for testing wavelet aberrations.

[0021] In the diagram: 1. Interferometer, 2. Attenuator, 3. CGH, 4. Spectrometer module, 5. Spectrometer frame, 6. First reflecting mirror frame, 7. Grating frame, 8. Third reflecting mirror frame, 9. First reflecting mirror, 10. Grating, 11. Third reflecting mirror, 12. Six-dimensional adjustment frame, 13. Metal pad, 14. Air-bearing platform, 15. Second reflecting mirror, 16. Second reflecting mirror frame, 17. Standard spherical mirror, 3-1. First master holographic region, 3-2. Second master holographic region, 3-3. Third master holographic region, 3-4. Fourth master holographic region, 3-5. First alignment holographic region, 3-6. Second alignment holographic region, 3-7. Third alignment holographic region, 3-8. First set of reference holographic regions, 3-9. Second set of reference holographic regions, 3-10. Third set of reference holographic regions. Detailed Implementation

[0022] Combination Figures 1 to 4 The assembly and adjustment method of the spectrometer system based on computational holographic devices in this invention is described in detail below:

[0023] Step 1: Optical Path Setup: Install the six-dimensional adjustment frame 12 and metal pad 13 on the air-floating platform 14. Install the interferometer 1 and attenuator 2 on the six-dimensional adjustment frame 12. Install the CGH3 spectrometer module 4 on the metal pad 13. Use the six-dimensional adjustment frame 12 and metal pad 13 to initially adjust the optical axes of the interferometer 1, attenuator 2, CGH3, and spectrometer module 4 to the same height using a ruler or other measurement methods.

[0024] Step 2: First Reflector Assembly and Positioning: Blocking other main holographic regions, the light emitted by interferometer 1 is incident on the first aligned holographic region 3-5 and returns to interferometer 1, forming interference fringes. Adjust the six-dimensional adjustment frame 12. When the fringes approach zero, the relative positional relationship between interferometer 1 and CGH3 can be determined. Blocking other diffraction regions, the light emitted by interferometer 1 is incident on the first reflector 9 through the first set of reference holographic regions 3-8, forming image points at the four edges of the surface of the first reflector 9. Adjust the first reflector frame 6. By visually observing that the four image points coincide with the four marked points on the first reflector frame, the initial position of the first reflector 9 is determined. Blocking other main holographic regions, the light emitted by interferometer 1 is incident on the first reflector 9 through the attenuator 2 and the first main holographic region 3-1. The reflected light returns to interferometer 1 through the first main holographic region 3-1, forming interference fringes. All other components remain stationary. Fine-tune the first reflector frame 6. When the interference fringes approach zero, the positioning of the first reflector 9 is completed.

[0025] Step 3: Grating Assembly and Positioning: Keeping all other components stationary, move only the six-dimensional adjustment frame 12 to block the other main holographic areas. The light from interferometer 1, incident on the second aligned holographic area 3-6, returns to interferometer 1, forming interference fringes. Adjust the six-dimensional adjustment frame 12; when the fringes approach zero, the relative positional relationship between interferometer 1 and CGH3 can be determined. The light emitted from interferometer 1, passing through the attenuator 2 and the second set of reference holographic areas 3-9, is incident on grating 10, forming four image points at the top, bottom, left, and right edges of grating 10. Adjust the grating frame 7, visually inspecting the four image points... The initial position of grating 10 is determined by the coincidence of the four marked points on the grating frame. The light emitted by interferometer 1 passes through attenuator 2 and the second principal holographic region 3-2 corresponding to the -1 order, and is incident on grating 10. After reflection, it returns to interferometer 1 to form interference fringes. The light emitted by interferometer 1 passes through attenuator 2 and the third principal holographic region 3-3 corresponding to the +1 order, and is incident on grating 10. After reflection, it returns to interferometer 1 to form interference fringes. Other components remain stationary. The grating frame 7 is finely adjusted. When the fringes of both interference orders approach the zero fringe, the positioning of grating 10 is completed.

[0026] Step 4, Third Reflector Installation and Positioning: Ensure all other components remain stationary, only move the six-dimensional adjustment frame 12 to block the other main holographic areas. The light from interferometer 1, incident on the third aligned holographic area 3-7, returns to interferometer 1, forming interference fringes. Adjust the six-dimensional adjustment frame 12; when the fringes approach zero, the relative positional relationship between interferometer 1 and CGH3 can be determined. Blocking the other main holographic areas, the light emitted from interferometer 1, passing through the third set of reference holographic areas 3-10, is incident on the third reflector 11, creating interference fringes on the surface of the third reflector 11. Four image points are formed at the right edge. The third reflecting mirror frame 8 is adjusted, and the initial position of the third reflecting mirror 11 is determined by visually observing the overlap between the four image points and the four marked points on the third reflecting mirror frame. Other diffraction areas are blocked. The light emitted by the interferometer 1 passes through the attenuator 2 and the fourth principal holographic region 3-4 and is incident on the third reflecting mirror 11. The reflected light returns to the interferometer 1 through the fourth principal holographic region 3-4 to form interference fringes. Other components remain stationary. The third reflecting mirror frame 8 is finely adjusted. When the interference fringes approach zero fringes, the positioning of the third reflecting mirror 11 is completed.

[0027] Step 5, Second Reflector Installation and Positioning: After the first reflector 9, the third reflector 11, and the grating 10 are positioned, remove CGH3, install the second reflector frame 16 (with the second reflector 15 fixed) on the spectrometer module 4, install the standard spherical mirror 17 at the object-side position of the off-axis freeform surface spectrometer system, move the focus of interferometer 1 to the image plane position of the off-axis freeform surface spectrometer system, the measurement beam is emitted from interferometer 1, passes through the spectrometer system, and is incident on the standard spherical mirror 17, the reflected light returns to interferometer 1 via 4 to form interference fringes, adjust the second reflector frame 16 according to the Zernike coefficient of the wave aberration theory so that the wave aberration of the spectrometer system meets the theoretical requirements, and complete the positioning of the second reflector 15.

Claims

1. An assembly and adjustment device for an off-axis freeform surface spectrometer system based on computational holography, comprising the assembly and adjustment device, characterized in that: The assembly and adjustment equipment consists of an interferometer (1), an attenuator (2), a computational holographic device (3), a spectrometer module (4), a six-dimensional adjustment frame (12), a metal pad (13), and an air-floating platform (14). The spectrometer module (4) consists of a spectrometer frame (5), a first reflecting mirror frame (6), a grating mirror frame (7), a third reflecting mirror frame (8), a first reflecting mirror (9), a grating (10), a third reflecting mirror (11), a second reflecting mirror (15), a second reflecting mirror frame (16), and a standard spherical mirror (17). The assembly and adjustment are completed through the following steps: Step 1: Using the six-dimensional adjustment frame (12) and metal pad (13), install the interferometer (1), attenuator (2), CGH (3), and spectrometer module (4) on the air-floating platform (14), and initially adjust the optical axis to the same height by measuring with a ruler; Step 2: The light emitted by the interferometer (1) is incident on the first aligned holographic region (3-5) of the CGH (3), and after reflection, it returns to the interferometer (1), forming interference fringes. The six-dimensional adjustment frame (12) is adjusted so that the first aligned holographic region (3-5) has zero fringes, and the six-dimensional adjustment frame (12) is fixed. The light emitted by the interferometer (1) is incident on the first set of reference holographic regions (3-8), producing four image points. The first reflecting mirror frame (6) is adjusted so that the four image points coincide with the four marked points on the first reflecting mirror frame, and the position of the first reflecting mirror (9) is initially determined. The light emitted by the interferometer (1) passes through the attenuator (2) and is incident on the first main holographic region (3-1), and then on the first reflecting mirror (9) of the spectrometer. The light is reflected back to the interferometer (1), forming interference fringes. The first reflecting mirror frame (6) is adjusted so that the interference fringes have zero fringes, and the position of the first reflecting mirror (9) is determined. Step 3: The light emitted by the interferometer (1) is incident on the second aligned holographic region (3-6) of the CGH (3), and after reflection, it returns to the interferometer (1), forming interference fringes. The six-dimensional adjustment frame (12) is adjusted so that zero fringes appear in the second aligned holographic region (3-6), and the six-dimensional adjustment frame (12) is fixed. The light emitted by the interferometer (1) is incident on the second set of reference holographic regions (3-9), producing four image points. The grating frame (7) is adjusted so that the four image points coincide with the four marked points on the grating frame, and the position of the grating (10) is initially determined. The interferometer... (1) The emitted light passes through the attenuator (2) and is incident on the second principal holographic region (3-2), and then on the spectrometer grating (10). The light is reflected back to the interferometer (1) to form interference fringes. The light emitted from the interferometer (1) passes through the attenuator (2) and is incident on the third principal holographic region (3-3), and then on the spectrometer grating (10). The light is reflected back to the interferometer (1) to form interference fringes. The grating frame (7) is adjusted so that the interference fringes of the two principal holographic regions are both zero fringes, and the position of the grating (10) is determined. Step 4: The light emitted by the interferometer (1) is incident on the third alignment holographic region (3-7) of the CGH (3), and after reflection, it returns to the interferometer (1) to form interference fringes. The six-dimensional adjustment frame (12) is adjusted so that the third alignment holographic region (3-7) has zero fringes, and the six-dimensional adjustment frame (12) is fixed. The light emitted by the interferometer (1) is incident on the third set of reference holographic regions (3-10) to generate four image points. The third reflecting mirror frame (8) is adjusted so that the four image points coincide with the marked points on the third reflecting mirror frame, and the position of the third reflecting mirror (11) is initially determined. The light emitted by the interferometer (1) passes through the attenuator (2) and is incident on the fourth main holographic region (3-4), and then on the third reflecting mirror (11) of the spectrometer. The light is reflected back to the interferometer (1) to form interference fringes. The third reflecting mirror frame (8) is adjusted so that the interference fringes have zero fringes, and the position of the third reflecting mirror (11) is determined. Step 5: Remove the computational holographic device (3), install the second reflector (15) onto the frame of the spectrometer module (4), and adjust the attitude of the second reflector frame (16) according to the theoretical wave aberration based on the optical path self-return principle of the standard spherical mirror (17) so that the wave aberration of the spectrometer system meets the requirements, thus completing the installation and adjustment of the second reflector (15).

2. The assembly and adjustment equipment for the off-axis freeform surface spectrometer system based on computational holographic devices according to claim 1, characterized in that: The computational holographic device (3) contains four main holographic regions, three alignment holographic regions, and three sets of reference holographic regions. The first main holographic region (3-1) corresponds to the first mirror (9), the second main holographic region (3-2) corresponds to the grating (10) -1 order, the third main holographic region (3-3) corresponds to the grating +1 order, and the fourth main holographic region (3-4) corresponds to the third mirror (11). The first alignment holographic region (3-5) is used to determine the relative positional relationship between the interferometer (1) and the CGH (3). The first main holographic region (3-1) is used to complete the attitude adjustment of the first mirror (9). The second alignment holographic region (3-6) is used to determine the relative positional relationship between the interferometer (1) and the CGH (3). To determine the relative positional relationship between the interferometer (1) and the CGH (3), the second main holographic region (3-2) and the third main holographic region (3-3) are used to complete the attitude adjustment of the grating (10). The third alignment holographic region (3-7) is used to determine the relative positional relationship between the interferometer (1) and the CGH (3). The fourth main holographic region (3-4) is used to complete the attitude adjustment of the third mirror (11). The first set of reference holographic regions (3-8) corresponds to the coarse adjustment position of the first mirror (9), the second set of reference holographic regions (3-9) corresponds to the coarse adjustment position of the grating (10), and the third set of reference holographic regions (3-10) corresponds to the coarse adjustment position of the third mirror (11).

3. The assembly and adjustment equipment for the off-axis freeform surface spectrometer system based on computational holography devices according to claim 1, characterized in that: By blocking other diffraction regions, the light emitted by the interferometer (1) is incident on the first aligned holographic region (3-5) and returns to the interferometer (1) to form interference fringes. The six-dimensional adjustment frame (12) is adjusted. When the fringes approach zero, the relative positional relationship between the interferometer (1) and the CGH (3) can be determined. By blocking other diffraction regions, the light emitted by the interferometer (1) is incident on the first reflecting mirror (9) through the first set of reference holographic regions (3-8), forming image points at four positions on the surface of the first reflecting mirror (9). The first reflecting mirror frame is adjusted. (6) Make the four image points coincide with the four marked points on the first reflecting mirror frame, blocking other diffraction areas. The light emitted by the interferometer (1) passes through the attenuator (2) and the first principal holographic region (3-1) and is incident on the first reflecting mirror (9). The reflected light returns to the interferometer (1) through the first principal holographic region (3-1) to form interference fringes. Fine-tune the first reflecting mirror frame (6). When the interference fringes approach zero fringes, the positioning of the first reflecting mirror (9) is completed. Ensure that the CGH (3) and the spectrometer module (4) remain stationary, blocking other diffraction areas. In the field, the light emitted by the interferometer (1) is incident on the second aligned holographic region (3-6) and returns to the interferometer (1) to form interference fringes. The six-dimensional adjustment frame (12) is adjusted. When the fringes approach zero, the relative positional relationship between the interferometer (1) and the CGH (3) can be determined. The light emitted by the interferometer (1) is incident on the grating (10) through the attenuator (2) and the second set of reference holographic regions (3-9), forming four image points on the surface of the grating (10) in the top, bottom, left, and right. The grating frame (7) is adjusted so that the four image points and the four marks on the edge of the grating frame are aligned. When the points coincide, the light emitted by the interferometer (1) passes through the attenuator (2) and the second principal holographic region (3-2) corresponding to the -1 order, and is incident on the grating (10). After reflection, it returns to the interferometer (1) to form interference fringes. The light emitted by the interferometer (1) passes through the attenuator (2) and the third principal holographic region (3-3) corresponding to the +1 order, and is incident on the grating (10). After reflection, it returns to the interferometer (1) to form interference fringes. Adjust the grating frame (7). When the fringes of both interference orders approach the zero fringe, the positioning of the grating (10) is completed.By blocking other diffraction regions, the light emitted by the interferometer (1) is incident on the third aligned holographic region (3-7) and returns to the interferometer (1) to form interference fringes. By adjusting the six-dimensional adjustment frame (12), when the fringes approach zero, the relative positional relationship between the interferometer (1) and the CGH (3) can be determined. By blocking other diffraction regions, the light emitted by the interferometer (1) is incident on the third reflecting mirror (11) through the third reference holographic region (3-10). The light is positioned on the surface of the third reflecting mirror (11) in the following positions: up, down, left, and right. Four image points are formed. The third reflecting mirror frame (8) is adjusted so that the four image points coincide with the four marked points on the third reflecting mirror frame, blocking other diffraction areas. The light emitted by the interferometer (1) passes through the attenuator (2) and the fourth principal holographic region (3-4) and is incident on the third reflecting mirror (11). The reflected light returns to the interferometer (1) through the fourth principal holographic region (3-4) to form interference fringes. The third reflecting mirror frame (8) is finely adjusted. When the interference fringes approach zero fringes, the positioning of the third reflecting mirror (11) is completed.

4. The assembly and adjustment equipment for the off-axis freeform surface spectrometer system based on computational holography devices according to claim 1, characterized in that: After the first reflecting mirror (9), grating (10), and third reflecting mirror (11) of the spectrometer module (4) are positioned, the CGH (3) is removed, and the second reflecting mirror frame (16) with the second reflecting mirror (15) fixedly installed is installed on the spectrometer module (4). The standard spherical mirror (17) is installed at the object-side position of the off-axis freeform surface spectrometer system. The focus of the interferometer (1) is moved to the image plane position of the off-axis freeform surface spectrometer system. The measurement beam is emitted through the interferometer (1), passes through the spectrometer system, and is incident on the standard spherical mirror (17). The reflected light returns to the interferometer (1) to form interference fringes. The second reflecting mirror frame (16) is adjusted according to the theoretical wave aberration so that the wave aberration of the spectrometer system meets the theoretical requirements, and the installation and adjustment of the second reflecting mirror (15) is completed.

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