Image acquisition unit calibration device and observation system suitable for on-orbit large field of view

Abstract

The present invention relates to the field of large-field-of-view observation, and particularly relates to a calibration device and an observation system for an on-orbit large-field-of-view image acquisition unit. The calibration device comprises a bracket assembly, a light source assembly, a diffuse reflection assembly, and a drive assembly. A basic light beam emitted by the light source is reflected by a reflector to form a primary reference beam. The primary reference beam is diffusely reflected by a diffuse reflection surface to form a secondary reference beam. The drive assembly drives the image acquisition unit to rotate, so that an image acquisition end of the image acquisition unit in a second cavity moves into a folding path of the secondary reference beam, and the image acquisition end is calibrated using the secondary reference beam. The drive assembly is further used to drive the image acquisition unit to move out of the folding path of the secondary reference beam after calibration is completed at the image acquisition end, so as to facilitate completion of a large-field-of-view observation operation when the image acquisition unit is rotated to a third opening. The entire calibration device has a simple design, and the working field and calibration field of view of the image acquisition unit are independent of each other, thereby achieving high reliability.

Description

Technical Field

[0001] The present invention relates to the field of large-field-of-view observation, and in particular to an image acquisition unit calibration device and an observation system suitable for on-orbit large-field-of-view. Background Art

[0002] As the on-orbit service life of space remote sensors increases, on-orbit radiation calibration systems are becoming increasingly important. Due to the advantages of the "standard lamp + diffuse reflector" method, such as a simple calibration model and easy full-field-of-view, many on-orbit calibration schemes internationally adopt this method. Currently, the field of view of on-orbit calibration achieved using this method is limited; generally, a rotation mechanism is incorporated into the system to achieve calibration and observation imaging modes for different functions. The calibration system is a relatively complex independent optical system with multiple transmission links, and the diffuse reflector enters the working field of view through a transmission mechanism for calibration. Summary of the Invention

[0003] In order to solve the above problems, the present invention provides an image acquisition unit calibration device and an observation system suitable for on-orbit large field of view, which solves the problems of complex structure and multiple transmission links of existing calibration systems.

[0004] To achieve the above objectives, in a first aspect, the present invention provides an image acquisition unit calibration device suitable for an on-orbit large field of view, comprising a bracket assembly, a light source assembly, a diffuse reflection assembly, and a drive assembly. The bracket assembly comprises a first bracket and a second bracket, the first bracket and the second bracket being arranged sequentially in a preset direction, the first bracket having a first cavity and a first opening, the first opening being arranged at an upper portion of the first bracket and communicating with the first cavity, the second bracket having a second cavity and a second opening and a third opening arranged oppositely, the second cavity communicating with the second opening and the third opening, respectively, the first opening coinciding with the second opening, the first cavity communicating with the second cavity, and the first opening and the third opening being coaxially arranged;

[0005] The light source assembly includes a light source and a reflector, the light source is arranged in the first cavity, the reflector is arranged at the center point of the first opening, the reflective surface of the reflector is arranged toward the output end of the light source, the light source is used to emit a basic light beam, the basic light beam is reflected by the reflector to form a primary reference light beam, and the reflective surface of the reflector is an annular spherical surface; the diffuse reflection assembly includes at least one diffuse reflection plate, at least one diffuse reflection plate is arranged on the second bracket and arranged along the circumference of the third opening, the diffuse reflection plate has a diffuse reflection surface, the diffuse reflection surface is arranged on the turning path of the primary reference light beam, and is used to diffusely reflect the primary reference light beam to form a secondary reference light beam; the driving assembly is arranged on the second bracket, the output end of the driving assembly is transmission-connected to the image acquisition unit, the image acquisition unit is arranged in the second cavity, and the driving assembly is used to drive the image acquisition unit to rotate so that the image acquisition end of the image acquisition unit moves into or out of the turning path of the secondary reference light beam.

[0006] In some embodiments, the image acquisition unit has at least one lens group to be calibrated, and the image acquisition end of the image acquisition unit is arranged on the lens group to be calibrated; the number of diffuse reflection plates corresponds to the number of lens groups to be calibrated.

[0007] In some embodiments, a reflective film is coated on the reflective surface of the reflector, and the reflective film includes a first reflective film and a second reflective film. The first reflective film and the second reflective film are symmetrically distributed on the reflective surface, and the first reflective film and the second reflective film reflect different light beam bands; the first-level reference beam is reflected by the first reflective film to form a first-level reference beam, and forms a first-level reference beam through a diffuse reflection plate; the first-level reference beam is also reflected by the second reflective film to form a second-level reference beam, and forms a second-level reference beam through the diffuse reflection plate.

[0008] In some embodiments, the image acquisition unit includes a first mirror group to be calibrated and a second mirror group to be calibrated, the first mirror group to be calibrated has a first image acquisition end, and the second mirror group to be calibrated has a second image acquisition end; the driving component is used to drive the first mirror group to be calibrated to rotate to a first preset angle so that the first image acquisition end captures the second primary reference beam, or to drive the second mirror group to be calibrated to rotate to a second preset angle so that the second image acquisition end captures the second secondary reference beam.

[0009] In some embodiments, the drive assembly includes a drive unit and a coupling. The drive unit is arranged on the second bracket. The output end of the drive unit passes through the second bracket and protrudes into the second cavity. The drive unit can drive the image acquisition unit to rotate within a preset calibration angle range; the coupling is transmission-connected to the output end of the drive unit, and the coupling is also transmission-connected to the image acquisition unit.

[0010] In some embodiments, the preset calibration angle range is -90° to 90°.

[0011] In a second aspect, the present invention also provides an observation system suitable for an on-orbit large field of view, comprising a calibration device and an image acquisition unit, wherein the calibration device is the calibration device described in the first aspect; the image acquisition unit has an image acquisition end, which is transmission-connected to the drive assembly and is arranged on a second bracket.

[0012] In some embodiments, the image acquisition unit further includes a to-be-calibrated mirror group, and the image acquisition end is disposed on the to-be-calibrated mirror group;

[0013] In some embodiments, the lens assembly to be calibrated includes at least one optical lens.

[0014] Compared with the prior art, the present invention can achieve the following beneficial effects:

[0015] The calibration device includes a bracket assembly, a light source assembly, a diffuse reflection assembly and a driving assembly. The bracket assembly includes a first bracket and a second bracket which are arranged in sequence according to a preset direction. The light source is arranged in the first cavity, the reflector is arranged at the center point of the first opening, and the diffuse reflection plate is arranged on the second bracket and is arranged along the circumference of the third opening. The basic light beam emitted by the light source is reflected by the reflector to form a primary reference beam, and the primary reference beam is diffusely reflected by the diffuse reflection surface to form a secondary reference beam. The driving assembly drives the image acquisition unit to rotate so that the image acquisition end of the image acquisition unit in the second cavity moves into the turning path of the secondary reference beam, and the image acquisition end is calibrated using the secondary reference beam. The driving assembly is also used to drive the image acquisition unit to move out of the turning path of the secondary reference beam after the image acquisition end completes calibration, so as to facilitate the completion of a large field of view observation operation when the image acquisition unit rotates to the third opening. The entire calibration device is simple in design, with few transmission links, and the working field and calibration field of view of the image acquisition unit are independent of each other, with high reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a first schematic diagram of a calibration device provided according to an embodiment of the present invention;

[0017] Figure 2 yes Figure 1 cross-sectional view;

[0018] Figure 3 is a schematic diagram of the optical path of the calibration device provided in an embodiment of the present invention;

[0019] Figure 4 is a second schematic diagram of the calibration device provided according to an embodiment of the present invention;

[0020] Figure 5 is a third schematic diagram of the calibration device provided according to an embodiment of the present invention.

[0021] Figure numerals: 1, bracket assembly; 11, first bracket; 12, second bracket; 2, light source assembly; 21, light source; 22, reflector; 3, diffuse reflection assembly; 31, diffuse reflection plate; 4, driving assembly; 5, mirror group to be calibrated. DETAILED DESCRIPTION

[0022] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the following description, identical modules are denoted by identical reference numerals. In the case of identical reference numerals, their names and functions are also identical. Therefore, their detailed description will not be repeated.

[0023] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and do not constitute a limitation of the present invention.

[0024] See also Figures 1 to 5 In a first aspect, the present embodiment provides an image acquisition unit calibration device suitable for a large field of view, including a bracket assembly 1, a light source assembly 2, a diffuse reflection assembly 3, and a drive assembly 4. The bracket assembly 1 includes a first bracket 11 and a second bracket 12. The first bracket 11 and the second bracket 12 are arranged in sequence according to a preset direction. The first bracket 11 has a first cavity and a first opening. The first opening is arranged at the upper part of the first bracket 11 and is connected to the first cavity. The second bracket 12 has a second cavity and a second opening and a third opening arranged oppositely. The second cavity is connected to the second opening and the third opening respectively. The first opening coincides with the second opening, the first cavity is connected to the second cavity, and the first opening and the third opening are coaxially arranged.

[0025] The light source assembly 2 includes a light source 21 and a reflector 22. The light source 21 is arranged in the first cavity, and the reflector 22 is arranged at the center point of the first opening. The reflective surface of the reflector 22 is arranged toward the output end of the light source 21. The light source 21 is used to emit a basic light beam, which is reflected by the reflector 22 to form a primary reference beam. The reflective surface of the reflector 22 is an annular spherical surface; the diffuse reflection assembly 3 includes at least one diffuse reflection plate 31. At least one diffuse reflection plate 31 is arranged on the second bracket 12 and is arranged along the circumference of the third opening. The diffuse reflection plate 31 has a diffuse reflection surface, which is arranged on the bending path of the primary reference beam and is used to diffusely reflect the primary reference beam to form a secondary reference beam; the driving assembly 4 is arranged on the second bracket 12, and the output end of the driving assembly 4 is transmission-connected to the image acquisition unit. The image acquisition unit is arranged in the second cavity. The driving assembly 4 is used to drive the image acquisition unit to rotate so that the image acquisition end of the image acquisition unit moves into or out of the bending path of the secondary reference beam.

[0026] In this embodiment, the preset direction refers to the observation direction of the field of view in actual application. For example, when the observation direction is a vertical direction, the image acquisition unit observes the field of view directly above the observation position, and the preset direction is also the vertical direction. The first bracket 11 and the second bracket 12 are arranged from bottom to top.

[0027] The second opening and the third opening are arranged on opposite sides of the second cavity. When the first bracket 11 and the second bracket 12 are arranged sequentially along the preset direction, the first opening and the second opening coincide with each other, the first cavity is connected to the second cavity, and the third opening is arranged in the preset direction. The third opening is coaxial with the first opening. It should be noted that the coaxial arrangement of the third opening and the first opening should be understood as follows: the axis passing through the center point of the first opening and extending in the preset direction is taken as the reference axis, and the center point of the third opening coincides with the reference axis.

[0028] In some optional embodiments, the first bracket 11 and the second bracket 12 are detachably connected. When the first bracket 11 and the second bracket 12 are assembled, that is, the first bracket 11 and the second bracket 12 are arranged in sequence along a preset direction, this method can connect the first bracket 11 and the second bracket 12 into one piece, which can improve the connection stability of the entire bracket assembly 1.

[0029] In this embodiment, light source 21 is capable of emitting a primary light beam, and this primary light beam is a conical beam. The reflective surface of reflector 22 is an annular spherical structure, and is positioned toward the output end of light source 21. The primary light beam is projected onto the reflective surface of reflector 22, where it reflects to form a circular primary reference beam. This primary light beam is then projected onto the diffuse reflective surface of diffuse reflector 31, where it utilizes the Lambertian properties of the diffuse reflective surface to form a secondary reference beam.

[0030] It should be noted that the number of diffuse reflection plates 31 can be one or more. It should be noted here that when there is one diffuse reflection plate 31, the diffuse reflection surface of the diffuse reflection plate 31 should cover the end face required for calibration of the image acquisition end of the image acquisition unit. When there are multiple diffuse reflection plates 31, the diffuse reflection surface composed of multiple diffuse reflection plates 31 should cover the end face required for calibration of the image acquisition end of the image acquisition unit.

[0031] In this embodiment, the image acquisition unit is arranged in the second cavity, the driving component 4 is arranged on the second bracket 12, and the output end of the driving component 4 is connected to the image acquisition unit for driving the image acquisition unit to rotate around the output end of the driving component 4. Part of the image acquisition unit can protrude to the outside of the third opening under the drive of the driving component 4. It should be noted that when the image acquisition end of the image acquisition unit is set toward the third opening, the light emitted by the external object to be observed can be transmitted to the imaging surface of the image acquisition unit through the image acquisition end, thereby realizing the image acquisition operation of the object to be observed. For the sake of distinction, in this embodiment, the moving area of ​​the image acquisition unit when the image acquisition end is set toward the third opening and can effectively acquire the object to be observed is recorded as the working field of view, and the moving area of ​​the image acquisition unit when the image acquisition end is set toward the deflecting path of the secondary reference beam to complete the calibration operation is recorded as the calibration field of view.

[0032] It should be noted that, in this embodiment, the diffuse reflection plate 31 is arranged in the circumferential direction of the third opening. Therefore, the distribution range of the secondary reference beam reflected by it is as follows: Figure 2 As shown, the image acquisition end of the image acquisition unit is driven by the driving component 4 to rotate to the deflection path of the secondary reference beam, and then the calibration operation of the image acquisition end is completed through the secondary reference beam.

[0033] In this embodiment, the image acquisition end refers to an optical path that allows external light to penetrate in and out, for example, it can be a light-transmitting area obtained by an optical lens. The specific structure of the image acquisition end shown in this embodiment is described below.

[0034] The calibration device shown in this embodiment is used as follows: the light source 21 emits a base beam, which is reflected by the reflector 22 to form a primary reference beam. The primary reference beam is projected onto a diffuse reflection surface, which diffusely reflects the primary reference beam to form a secondary reference beam. The drive assembly 4 rotates the image acquisition unit so that the image acquisition end of the image acquisition unit is placed on the deflection path of the secondary reference beam, thereby achieving calibration of the image acquisition end. The calibration process can also be understood as follows: the light emitted by the light source 21 is reflected by the reflector 22 and then illuminates the diffuse reflection plate 31. The diffuse reflection plate 31 has Lambertian characteristics, forming a surface light source 21, which enters the to-be-calibrated lens group 5, completing the calibration.

[0035] The technical solution shown in this embodiment has a simple structure, fewer transmission links, and the working field of view and calibration field of view of the image acquisition unit are independent of each other, so the reliability is high.

[0036] In some embodiments, the image acquisition unit has at least one lens group to be calibrated 5 , and the image acquisition end of the image acquisition unit is arranged on the lens group to be calibrated 5 ; the number of diffuse reflection plates 31 corresponds to the number of lens groups to be calibrated 5 .

[0037] In this embodiment, the lens assembly 5 to be calibrated refers to an assembly comprising at least one optical lens. The image acquisition end of the image acquisition unit is also the light-transmitting area of ​​the optical lens. The lens assembly 5 to be calibrated refers to an optical lens assembly that has not yet completed calibration. Preferably, the number of diffuse reflection plates 31 corresponds one-to-one to the number of lens assemblies 5 to be calibrated. That is, the secondary reference beam reflected by the diffuse reflection surface of one diffuse reflection plate 31 is used for the calibration operation of one lens assembly 5 to be calibrated. Preferably, when the lens assembly 5 to be calibrated is rotated to the calibration field of view, the diffuse reflection plate 31 is placed at the geometric center of the lens assembly 5 to be calibrated.

[0038] In some embodiments, a reflective film is coated on the reflective surface of the reflector 22, and the reflective film includes a first reflective film and a second reflective film. The first reflective film and the second reflective film are symmetrically distributed on the reflective surface, and the first reflective film and the second reflective film reflect different light beam bands; the first-level reference beam is reflected by the first reflective film to form a first-level reference beam, and forms a first-level reference beam through the diffuse reflection plate 31; the first-level reference beam is also reflected by the second reflective film to form a second-level reference beam, and forms a second-level reference beam through the diffuse reflection plate 31.

[0039] In this embodiment, the first and second reflective films are electroplated on the reflective surface. It should be noted that the first and second reflective films reflect different wavelengths of light beams, and the specific type of reflective film can be selected based on actual needs. For example, the first reflective film is used to reflect light beams in a first wavelength band, and the second reflective film is used to reflect light beams in a second wavelength band.

[0040] This embodiment can achieve calibration operations for the calibrated lens group 5 in different wavelength bands, while also avoiding the influence of other stray light on the calibration process. Preferably, the calibration requirements of multiple different wavelength bands can also be achieved by coating a third reflective film, a fourth reflective film, etc.

[0041] In some embodiments, the image acquisition unit includes a first mirror group to be calibrated and a second mirror group to be calibrated, the first mirror group to be calibrated has a first image acquisition end, and the second mirror group to be calibrated has a second image acquisition end; the driving component 4 is used to drive the first mirror group to be calibrated to rotate to a first preset angle so that the first image acquisition end captures the second primary reference beam, or to drive the second mirror group to be calibrated to rotate to a second preset angle so that the second image acquisition end captures the second secondary reference beam.

[0042] The first and second calibration mirror groups are arranged in two rows and two columns on the drive assembly 4. There are two first calibration mirror groups, and the two first calibration mirror groups together form a field of view of 130°×10°, and together they form observation channel 1. There are two second calibration mirror groups 5, and the two second calibration mirror groups together form a field of view of 130°×10°, and together they form observation channel 2. In the operating mode, the drive assembly 4 drives the first and second calibration mirror groups to scan between -60° and 60°, so that the field of view in the operating mode ranges from 130°×130°. The diffuse reflection plates 31 are evenly distributed at the geometric centers of the first mirror group to be calibrated and the second mirror group to be calibrated and are fixed on the second bracket 12. In the calibration mode, the driving component 4 rotates to -90° during calibration, and the first mirror group to be calibrated corresponds to one of the diffuse reflection plates 31, and the diffuse reflection plate 31 corresponds to the first reflection film setting. During calibration, the driving component 4 rotates to 90°, and the second mirror group to be calibrated corresponds to the other diffuse reflection plate 31, and the diffuse reflection plate 31 corresponds to the second reflection film setting.

[0043] In some embodiments, the drive assembly 4 includes a drive unit and a coupling. The drive unit is arranged on the second bracket 12. The output end of the drive unit passes through the second bracket 12 and protrudes into the second cavity. The drive unit can drive the image acquisition unit to rotate within a preset calibration angle range; the coupling is transmission-connected to the output end of the drive unit, and the coupling is also transmission-connected to the image acquisition unit.

[0044] In this embodiment, the drive unit is preferably a servo motor, and the coupling is provided between the image acquisition unit and the output end of the drive unit. It should be noted that the preset calibration angle range refers to the field of view range involved in the rotation angle of the image acquisition unit during calibration, that is, the calibration field of view mentioned above.

[0045] In some embodiments, the preset calibration angle range is -90° to 90°.

[0046] In the second aspect, this embodiment also provides an observation system suitable for a large field of view, including a calibration device and an image acquisition unit, the calibration device is the calibration device described in the first aspect; the image acquisition unit has an image acquisition end, the image acquisition end is transmission-connected to the drive assembly 4, and is arranged on the second bracket 12.

[0047] It should be noted that, in this embodiment, the image acquisition unit has a calibration field of view and a working field of view, that is, the field of view range involved in the preset observation rotation angle range described later. The preset calibration rotation angle range corresponding to the calibration field of view is larger than the preset observation rotation angle range. When the image acquisition unit needs to be calibrated, the drive component 4 can be controlled to drive the image acquisition unit to rotate. After the calibration is completed, it can be directly rotated to the preset observation rotation angle range corresponding to the working field of view, thereby realizing the on-orbit calibration requirements of the image acquisition unit.

[0048] In some embodiments, the image acquisition unit further includes a lens group to be calibrated 5 , and the image acquisition end is arranged on the lens group to be calibrated 5 .

[0049] In some embodiments, the lens assembly 5 to be calibrated includes at least one optical lens.

[0050] In the above technical solution, the calibration device includes a bracket assembly 1, a light source assembly 2, a diffuse reflection assembly 3 and a drive assembly 4. The bracket assembly 1 includes a first bracket 11 and a second bracket 12 arranged in sequence according to a preset direction. The light source 21 is arranged in the first cavity, the reflector 22 is arranged at the center point of the first opening, and the diffuse reflection plate 31 is arranged on the second bracket 12 and arranged along the circumference of the third opening; the basic light beam emitted by the light source 21 is reflected by the reflector 22 to form a primary reference beam, and the primary reference beam is diffusely reflected by the diffuse reflection surface to form a secondary reference beam. The drive assembly 4 drives the image acquisition unit to rotate so that the image acquisition end of the image acquisition unit in the second cavity moves into the turning path of the secondary reference beam, and the image acquisition end is calibrated using the secondary reference beam. The drive assembly 4 is also used to drive the image acquisition unit to move out of the turning path of the secondary reference beam after the image acquisition end completes calibration, so as to facilitate the completion of a large field of view observation operation when the image acquisition unit rotates to the third opening. The entire calibration device is simple in design, with few transmission links, and the working field and calibration field of the image acquisition unit are independent of each other, with high reliability.

[0051] It should be understood that the various forms of the processes shown above can be used to reorder, add, or delete steps. For example, the steps described in the present disclosure can be performed in parallel, sequentially, or in a different order, as long as the desired results of the technical solutions disclosed in the present disclosure can be achieved. This is not limited herein.

[0052] The above specific embodiments do not limit the scope of protection of the present invention. Those skilled in the art will appreciate that various modifications, combinations, sub-combinations, and substitutions may be made based on design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention are intended to be included within the scope of protection of the present invention.

Claims

1. A calibration device for an image acquisition unit with a large field of view on-orbit, characterized in that: include: A bracket assembly includes a first bracket and a second bracket, the first bracket and the second bracket are arranged in sequence according to a preset direction, the first bracket has a first cavity and a first opening, the first opening is arranged at the upper portion of the first bracket, the first opening is communicated with the first cavity, the second bracket has a second cavity and a second opening and a third opening arranged opposite to each other, the second cavity is communicated with the second opening and the third opening respectively, the first opening coincides with the second opening, the first cavity is communicated with the second cavity, and the first opening and the third opening are arranged coaxially; A light source assembly, comprising a light source and a reflector, wherein the light source is disposed in the first cavity, the reflector is disposed at the center of the first opening, the reflective surface of the reflector is disposed toward the output end of the light source, the light source is configured to emit a primary light beam, the primary light beam is reflected by the reflector to form a primary reference beam, and the reflective surface of the reflector is an annular spherical surface; a diffuse reflection assembly, comprising at least one diffuse reflection plate, wherein the at least one diffuse reflection plate is disposed on the second bracket and arranged along the circumference of the third opening, the diffuse reflection plate having a diffuse reflection surface, the diffuse reflection surface being disposed on the deflection path of the primary reference beam and configured to diffusely reflect the primary reference beam to form a secondary reference beam; a drive assembly disposed on the second bracket, wherein an output end of the drive assembly is in transmission connection with an image acquisition unit disposed in the second cavity, and the drive assembly is configured to drive the image acquisition unit to rotate so as to move an image acquisition end of the image acquisition unit into or out of the folding path of the secondary reference beam; The image acquisition unit has at least one lens group to be calibrated, and the image acquisition end of the image acquisition unit is arranged on the lens group to be calibrated; the number of the diffuse reflection plates corresponds to the number of the lens groups to be calibrated; The reflective surface of the reflector is coated with a reflective film, the reflective film including a first reflective film and a second reflective film, the first reflective film and the second reflective film are symmetrically distributed on the reflective surface, and the first reflective film and the second reflective film reflect different light beam bands; The first-level reference beam is reflected by the first reflective film to form a first first-level reference beam, and forms a first second-level reference beam through the diffuse reflective plate. The first-level reference beam is also reflected by the second reflective film to form a second first-level reference beam, and forms a second second-level reference beam through the diffuse reflective plate.

2. The image acquisition unit calibration device suitable for on-orbit large field of view according to claim 1, characterized in that: The image acquisition unit includes a first to-be-calibrated mirror group and a second to-be-calibrated mirror group, wherein the first to-be-calibrated mirror group has a first image acquisition end, and the second to-be-calibrated mirror group has a second image acquisition end; The driving component is used to drive the first to-be-calibrated mirror group to rotate to a first preset angle so that the first image acquisition end collects the second primary reference beam, or to drive the second to-be-calibrated mirror group to rotate to a second preset angle so that the second image acquisition end collects the second secondary reference beam.

3. The image acquisition unit calibration device suitable for on-orbit large field of view according to claim 1, characterized in that: The drive assembly includes: a driving unit, disposed on the second bracket, wherein an output end of the driving unit passes through the second bracket and protrudes into the second cavity, and the driving unit can drive the image acquisition unit to rotate within a preset calibration angle range; A coupling is in driving connection with the output end of the driving unit, and the coupling is also in driving connection with the image acquisition unit.

4. The image acquisition unit calibration device suitable for on-orbit large field of view according to claim 3, characterized in that: The preset calibration angle range is -90° to 90°.

5. An observation system suitable for large field of view on orbit, characterized in that: include: The calibration device is a calibration device for an image acquisition unit with a large field of view on-orbit as claimed in any one of claims 1 to 4; The image acquisition unit comprises an image acquisition end, which is transmission-connected to the driving assembly and is disposed on the second bracket.

6. The on-orbit large field of view observation system according to claim 5, characterized in that: The image acquisition unit further includes: The mirror group to be calibrated, the image acquisition end is arranged on the mirror group to be calibrated.

7. The on-orbit large field of view observation system according to claim 6, characterized in that: The lens group to be calibrated includes at least one optical lens.

Images