Space area array hyperspectral camera focal plane assembly

Abstract

The invention discloses a focal plane assembly of a space area array hyperspectral camera, belongs to the technical field of space remote sensing, and aims to solve the problems of large size, heavy weight and complex structure of a camera in the prior art. The device comprises a focal plane support and a dichroic mirror assembly installed in the focal plane support. The two groups of light splitting reflecting mirror assemblies are arranged in the focal plane bracket; the spectrum detector assemblies are installed on the focal plane support, one of the four spectrum detector assemblies is symmetrical to the light splitting reflector assembly, and the other two of the four spectrum detector assemblies are symmetrical to the other light splitting reflector assembly; the incident light is subjected to color separation through a dichroic mirror of the dichroic mirror assembly, and the reflected light is irradiated to one group of light splitting reflecting mirror assembly and is irradiated to the area array detectors of the two corresponding groups of spectrum detector assemblies after light splitting; and the transmitted light irradiates the other group of light splitting reflector assemblies, and irradiates the area array detectors of the two corresponding groups of spectrum detector assemblies after light splitting.

Description

Technical Field

[0001] The invention belongs to the technical field of space remote sensing, and in particular relates to a focal plane component of a space array hyperspectral camera. Background Art

[0002] The miniaturization of satellites and space cameras is an important trend in the current field of space remote sensing. It is an important prerequisite for realizing the technology of launching multiple satellites with one rocket, saving development and launch costs, and shortening the development cycle. Miniaturization is to some extent contrary to the observation efficiency of space cameras. The limitations of aperture and field of view severely restrict the installation and layout of many functional units of small space cameras.

[0003] Hyperspectral remote sensing has outstanding advantages in the fine classification and identification of ground objects. It has become an important technical means for space-based reconnaissance and has played an important role in the identification and analysis of camouflaged targets and true and false targets on the ground and at sea. Array staring imaging combined with agile satellite maneuvering technology can effectively monitor hot spots for a long time, and is the main working mode of many micro-satellites. Traditional array hyperspectral cameras mostly use color separation prisms, gratings, slits and other components to achieve one-dimensional spectral segmentation, combined with field of view scanning mechanisms to achieve two-dimensional array spectral imaging, or use filter wheel switching to achieve array spectral segmentation. The traditional method system is large in size, complex in structure, and has low reliability. The application of pixel-level multi-layer filter film technology realizes the array hyperspectral segmentation function at the detector end, reducing the size, weight and complexity of the camera. However, due to the current multi-layer filter film manufacturing cost and technical level, the single-chip detector target surface cannot be too large and the spectral range cannot fully cover the working band due to the restriction of spectral resolution. Therefore, the array hyperspectral focal plane assembly needs to be spliced ​​with multiple array detectors to achieve it. For miniature space cameras, it is a challenge to achieve field of view segmentation, spectral separation, mechanical installation and detector splicing within a limited space while ensuring their adaptability and stability to the space mechanical and thermal environment. Summary of the invention

[0004] The purpose of the present invention is to propose a focal plane assembly of a spatial array hyperspectral camera suitable for limited spatial volume, highly folded and integrated optical paths, and high-precision splicing of multiple detectors, so as to solve the problems of large size, heavy weight and complex structure of cameras in the prior art.

[0005] To achieve the above object, a focal plane assembly of a spatial array hyperspectral camera of the present invention comprises:

[0006] A focal plane bracket, wherein the focal plane bracket is provided with a first reference plane, a first parallel plane, a second reference plane, a component mounting surface, a glue injection hole and a prefabricated pin hole; the first parallel plane is bilaterally symmetrical with the first reference plane, the coplanarity is better than 0.003mm, the parallelism with the first reference plane is better than 0.005mm, the perpendicularity between the second reference plane and the first reference plane is better than 0.005mm; the perpendicularity between the component mounting surface and the first reference plane is better than 0.01mm;

[0007] A dichroic mirror assembly is positioned and installed on the mounting surface of the internal component of the focal plane bracket through a prefabricated pin hole; the dichroic mirror of the dichroic mirror assembly is coated with a dichroic film and an anti-reflection film on both sides, with a reflection band of 450nm to 600nm and a transmission band of 600nm to 860nm;

[0008] A first beam splitter reflector assembly and a second beam splitter reflector assembly are installed in the focal plane bracket and positioned by injection molding through the injection hole, and the first beam splitter reflector assembly and the second beam splitter reflector assembly receive reflected light and transmitted light of the dichroic mirror assembly respectively;

[0009] Four groups of spectral detector assemblies with the same structure are installed on the first reference plane and the first parallel plane, namely, a first spectral detector assembly, a second spectral detector assembly, a third spectral detector assembly and a fourth spectral detector assembly, the first spectral detector assembly and the second spectral detector assembly are symmetrical with respect to the first beam splitter reflector assembly, and the third spectral detector assembly and the fourth spectral detector assembly are symmetrical with respect to the second beam splitter reflector assembly;

[0010] and a dust cover arranged at the upper end of the focal plane support;

[0011] The incident light irradiates the dichroic mirror of the dichroic mirror assembly, and the light reflected by the dichroic mirror is split by the first beam splitting reflector assembly and irradiates the first spectral image plane of the first spectrum detector assembly and the second spectral image plane of the second spectrum detector assembly; the light transmitted by the dichroic mirror is split by the second beam splitting reflector assembly and irradiates the third spectral image plane of the third spectrum detector assembly and the fourth spectral image plane of the fourth spectrum detector assembly.

[0012] The focal plane support material is Invar, and the linear expansion coefficient is customized to be ≤0.6×10 -6 .

[0013] The first reference plane of the focal plane bracket is composed of four coplanar rectangular bosses with a coplanarity better than 0.003 mm; the flatness of the second reference plane is better than 0.003 mm, and the flatness of the component mounting surface is better than 0.003 mm.

[0014] The diameter of the glue injection hole is Φ2.5mm, and optical epoxy glue is injected into the mounting interface corresponding to the first beam splitter reflector assembly and the second beam splitter reflector assembly and the focal plane bracket through the glue injection hole for bonding, curing and positioning; the diameter of the prefabricated pin hole is Φ2.8mm, and the pin is connected and positioned with the color separation mirror assembly through the prefabricated pin hole on the focal plane bracket.

[0015] The dichroic mirror assembly comprises a dichroic mirror, a dichroic mirror frame, a thin sheet flexible structure and a dichroic mirror adjustment pad; the dichroic mirror and the dichroic mirror frame are bonded and assembled; the thin sheet flexible structure and the dichroic mirror adjustment pad are sequentially arranged between the dichroic mirror frame and the component mounting surface inside the focal plane bracket; the adhesive between the dichroic mirror and the dichroic mirror frame is an optical epoxy glue; the dichroic mirror material is quartz glass, with a minimum thickness of 4mm and a surface root mean square value better than 12nm; the dichroic mirror frame material is Invar, and the linear expansion coefficient is customized to be ≤0.6×10 -6 , the thin-sheet flexible structure includes two sheets.

[0016] The first beam splitter reflector assembly is composed of a first beam splitter reflector and a base. A cylindrical boss is processed on the bottom of the first beam splitter reflector, and the cylindrical surface is a bonding surface. The cylindrical surface of the first beam splitter reflector is bonded and fixed to the base through three flexible structures evenly distributed around the circumference. The first beam splitter reflector is made of microcrystalline glass. The verticality of the two reflecting surfaces of the first beam splitter reflector is better than 0.005mm, and the surface shape is better than 12nm. The base is made of invar steel, and the linear expansion coefficient is customized to be ≤0.6×10 -6 .

[0017] The first spectrum detector assembly and the second spectrum detector assembly correspond to a detection spectrum range of 450nm to 600nm, and the third spectrum detector assembly and the fourth spectrum detector assembly correspond to a detection spectrum range of 600nm to 860nm.

[0018] The first spectral detector assembly, the second spectral detector assembly, the third spectral detector assembly and the fourth spectral detector assembly have the same structure and are connected to the focal plane bracket in the same way; the first spectral detector assembly consists of a planar array detector, a detector frame and a bandpass filter; the detector frame is processed with a rectangular groove, and the planar array detector is installed in the rectangular groove of the detector frame, and the size of the rectangular groove is 0.05mm to 0.1mm larger than the detector's outer size on one side; during installation, thermal conductive glue is evenly applied on all sides of the planar array detector and then embedded in the rectangular groove of the detector frame, and the bandpass filter is bonded to the other side of the detector frame after the glue layer is cured, and a detector cover is provided on the outside of the first spectral detector assembly.

[0019] The first spectral detector assembly is fixed on the focal plane bracket through a detector adjustment pad, and the front and back and inclination of the target surface of the area array detector in each group of spectral detector assemblies are adjusted by adjusting the thickness and inclination of the detector adjustment pad; the detector adjustment pad is a double-sided double-boss structure, the coplanarity of the double boss is better than 0.003mm, and the parallelism of the two sides is better than 0.005mm.

[0020] The focal plane assembly also includes a reference quasi-cubic mirror assembly arranged on the second reference plane. The reference cubic mirror assembly is a cube with a side length of 14 mm, whose I surface is parallel to the first reference plane of the focal plane bracket, and whose II surface is parallel to the second reference plane of the focal plane bracket. The installation error is better than 3". The reference cubic mirror assembly is used to quickly align with the camera coordinate system when the hyperspectral focal plane is integrated with the lens.

[0021] The beneficial effects of the present invention are as follows: a spatial array hyperspectral camera focal plane assembly of the present invention realizes transmission and reflection of light beams to realize splitting of different bands through a color separation mirror, and receives the transmitted and reflected light rays through two groups of light reflection mirror assemblies respectively. Furthermore, reflection splitting is realized through two groups of light reflection mirror assemblies and irradiates the light rays to four groups of spectral detector assemblies respectively, thereby realizing the splicing of the array detectors of the array hyperspectral focal plane assembly. For a micro-sized space camera, it plays a positive role in realizing field of view segmentation, spectral band color separation, mechanical installation and detector splicing within a limited space range and ensuring its adaptability and stability to the space mechanical and thermal environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic diagram of the optical path of a focal plane component of a spatial array hyperspectral camera of the present invention;

[0023] Figure 2 This is a schematic structural diagram of a focal plane assembly of a spatial array hyperspectral camera of the present invention;

[0024] Figure 3 A top view of a focal plane assembly structure of a spatial array hyperspectral camera of the present invention without a dust cover;

[0025] Figure 4 It is a left view of the focal plane assembly structure of a spatial array hyperspectral camera of the present invention without the aperture piece;

[0026] Figure 5 A schematic structural diagram showing a side view of a focal plane bracket in a focal plane assembly of a spatial array hyperspectral camera of the present invention;

[0027] Figure 6 A schematic structural diagram showing another side of a focal plane bracket in a focal plane assembly of a spatial array hyperspectral camera of the present invention;

[0028] Figure 7A bottom view of a focal plane support in a focal plane assembly of a spatial array hyperspectral camera of the present invention;

[0029] Figure 8 It is a schematic diagram of the structure of a dichroic mirror assembly in a focal plane assembly of a spatial array hyperspectral camera of the present invention;

[0030] Fig. 9 It is a schematic structural diagram of a beam splitting reflector assembly in a focal plane assembly of a spatial array hyperspectral camera of the present invention;

[0031] Fig.10 It is a side schematic diagram of a spectral detector component in a focal plane component of a spatial array hyperspectral camera of the present invention;

[0032] Fig.11 It is another side view schematic diagram of a spectral detector assembly in a focal plane assembly of a spatial array hyperspectral camera of the present invention;

[0033] Fig.12 It is a schematic diagram of the structure of a detector adjustment pad in a focal plane assembly of a spatial array hyperspectral camera of the present invention;

[0034] Wherein: 1. focal plane bracket, 101. first reference plane, 102. first parallel plane, 103. second reference plane, 104. component mounting surface, 105. glue injection hole, 106. prefabricated pin hole, 2. dichroic mirror assembly, 201. dichroic mirror, 202. dichroic mirror frame, 203. sheet-type flexible structure, 204. dichroic mirror adjustment pad, 3. first beam splitter reflector assembly, 301. first beam splitter reflector, 302. base, 303. flexible structure, 4. second beam splitter reflector, 401. Dichroic reflector, 5. First spectral detector assembly, 501. Plane array detector, 502. Detector frame, 503. Bandpass filter, 504. Detector adjustment pad, 505. Detector cover, 506. First spectral image plane, 6. Second spectral detector assembly, 601. Second spectral image plane, 7. Third spectral detector assembly, 701. Third spectral image plane, 8. Fourth spectral detector assembly, 801. Fourth spectral image plane, 9. Dust cover, 10. Aperture piece, 11. Reference cubic mirror assembly. DETAILED DESCRIPTION

[0035] The embodiments of the present invention will be further described below in conjunction with the accompanying drawings.

[0036] See also Figure 1-Figure 7 A focal plane assembly of a spatial array hyperspectral camera of the present invention comprises:

[0037] A focal plane bracket 1, wherein the focal plane bracket 1 is provided with a first reference plane 101, a first parallel plane 102, a second reference plane 103, a component mounting surface 104, four glue injection holes 105 and two prefabricated pin holes 106; the first parallel plane 102 is bilaterally symmetrical with the first reference plane 101, the coplanarity is better than 0.003mm, the parallelism with the first reference plane 101 is better than 0.005mm, the second reference plane 103 is better than 0.005mm perpendicular to the first reference plane 101; the component mounting surface 104 is better than 0.01mm perpendicular to the first reference plane 101;

[0038] The dichroic mirror assembly 2 is positioned and installed on the internal assembly mounting surface 104 of the focal plane bracket 1 through the prefabricated pin hole 106; the dichroic mirror 201 of the dichroic mirror assembly 2 is coated with a dichroic film and an anti-reflection film on both sides, with a reflection band of 450nm to 600nm and a transmission band of 600nm to 860nm;

[0039] A first beam splitter reflector assembly 3 and a second beam splitter reflector assembly 4 are installed in the focal plane bracket 1 and positioned by injection molding through the injection hole 105, and the first beam splitter reflector assembly 3 and the second beam splitter reflector assembly 4 receive the reflected light and the transmitted light of the dichroic mirror assembly 2 respectively;

[0040] Four groups of spectral detector assemblies with the same structure are installed on the first reference plane 101 and the first parallel plane 102, namely, the first spectral detector assembly 5, the second spectral detector assembly 6, the third spectral detector assembly 7 and the fourth spectral detector assembly 8, the first spectral detector assembly 5 and the second spectral detector assembly 6 are symmetrical with respect to the first spectroscopic reflector assembly 3, and the third spectral detector assembly 7 and the fourth spectral detector assembly 8 are symmetrical with respect to the second spectroscopic reflector assembly 4;

[0041] An aperture piece 10 arranged at the light entrance of the focal plane support 1;

[0042] and a dust cover 9 arranged at the upper end of the focal plane support 1;

[0043] The incident light irradiates the dichroic mirror 201 of the dichroic mirror assembly 2 after passing through the aperture piece 10, and the light reflected by the dichroic mirror 201 irradiates the first beam splitting reflector assembly 3, and after being split by the first beam splitting reflector assembly 3, it irradiates the corresponding two groups of area array detectors 501 of spectral detector assemblies, that is, the first spectral image plane 506 of the first spectral detector assembly 5 and the second spectral image plane 601 of the second spectral detector assembly 6; the light transmitted by the dichroic mirror 201 irradiates the second beam splitting reflector assembly 4, and after being split by the second beam splitting reflector assembly 4, it irradiates the corresponding two groups of area array detectors 501 of spectral detector assemblies, that is, the third spectral image plane 701 of the third spectral detector assembly 7 and the fourth spectral image plane 801 of the fourth spectral detector assembly 8.

[0044] The focal plane support 1 is made of Invar steel, and its linear expansion coefficient is customized to be ≤0.6×10 -6 .

[0045] The first reference plane 101 of the focal plane bracket 1 is composed of four coplanar rectangular bosses with a coplanarity better than 0.003 mm; the flatness of the second reference plane 103 is better than 0.003 mm, and the flatness of the component mounting surface 104 is better than 0.003 mm.

[0046] The diameter of the injection hole 105 is Φ2.5mm, and optical epoxy glue is injected into the mounting interface corresponding to the first beam splitter reflector assembly 3 and the second beam splitter reflector assembly 4 and the focal plane bracket 1 through the injection hole 105 for bonding, curing and positioning; the diameter of the prefabricated pin hole 106 is Φ2.8mm, and the pin is connected and positioned with the dichroic mirror assembly 2 through the prefabricated pin hole 106 on the focal plane bracket 1. The reason why the first beam splitter reflector assembly 3, the second beam splitter reflector assembly 4 and the dichroic mirror assembly 2 adopt the above two positioning methods is that the positioning accuracy will be slightly lost when the pin is drilled. In order to ensure the final splicing accuracy of the detector under the splicing instrument, the use of optical epoxy glue is the most reliable.

[0047] See also Figure 8 The dichroic mirror assembly 2 comprises a dichroic mirror 201, a dichroic mirror frame 202, a thin sheet flexible structure 203 and a dichroic mirror adjustment pad 204; the dichroic mirror 201 and the dichroic mirror frame 202 are bonded and assembled; the thin sheet flexible structure 203 and the dichroic mirror adjustment pad 204 are sequentially arranged between the dichroic mirror frame 202 and the component mounting surface 104 inside the focal plane bracket 1; the adhesive between the dichroic mirror 201 and the dichroic mirror frame 202 is an optical epoxy glue; the dichroic mirror 201 is made of quartz glass, has a nominal wedge angle of 0.375° (in order to correct the aberration introduced by color separation and ensure the imaging quality), a minimum thickness of 4mm, and a surface root mean square value better than 12nm; the dichroic mirror frame 202 is made of Invar (grade 4J32), and the linear expansion coefficient is customized to be ≤0.6×10 -6 The thin-sheet flexible structure 203 includes two sheets, which are used to isolate the installation stress and ensure the surface shape of the dichroic mirror 201.

[0048] The dichroic mirror adjustment pad 204 has the same shape as the bottom mounting surface of the dichroic mirror frame 202 , similar to the middle layer of a sandwich, and is located between the base of the dichroic mirror frame 202 and the component mounting surface 104 of the focal plane bracket 1 . The installation pointing angle of the dichroic mirror assembly 2 is adjusted by grinding the dichroic mirror adjustment pad 204 .

[0049] See also Fig. 9The first beam splitter reflector assembly 3 and the second beam splitter reflector assembly 4 have the same structure. The first beam splitter reflector assembly 3 is composed of a first beam splitter reflector 301 and a base 302. The bottom of the first beam splitter reflector 301 is processed with a cylindrical boss, and the cylindrical surface is a bonding surface, which can significantly improve the influence of bonding stress on the surface shape of the reflecting surface. The cylindrical surface of the first beam splitter reflector 301 is bonded and fixed to the base 302 through three flexible structures 303 evenly distributed around the circumference. The three flexible structures 303 are provided to eliminate the influence of component installation stress on the surface shape of the reflecting surface; the adhesive is preferably optical epoxy glue, the material of the first beam splitter reflector 301 is microcrystalline glass, the verticality of the two reflecting surfaces of the first beam splitter reflector 301 is better than 0.005mm, and the surface shape is better than 12nm; the material of the base 302 is Invar (grade 4J32), and the linear expansion coefficient is customized to be ≤0.6×10 -6 The beam splitter reflector in the second beam splitter reflector assembly 4 is marked as a second beam splitter reflector 401 .

[0050] The first spectrum detector assembly 5 and the second spectrum detector assembly 6 correspond to the detection spectrum range of 450nm to 600nm, and the third spectrum detector assembly 7 and the fourth spectrum detector assembly 8 correspond to the detection spectrum range of 600nm to 860nm.

[0051] See also Fig.10 and Fig.11 The first spectral detector assembly 5, the second spectral detector assembly 6, the third spectral detector assembly 7 and the fourth spectral detector assembly 8 have the same structure and are connected in the same way as the focal plane bracket 1; the first spectral detector assembly 5 is composed of a planar array detector 501, a detector frame 502 and a bandpass filter 503; the detector frame 502 is processed with a rectangular groove, and the planar array detector 501 is installed in the rectangular groove of the detector frame 502. The detector package dimensions are measured, and the rectangular groove size is 0.05mm to 0.1mm larger than the detector dimensions on one side; during installation, the planar array detector 501 is evenly coated with thermal conductive glue (preferably GD414C) around it and then embedded in the rectangular groove of the detector frame 502 to ensure good thermal contact around it, and the overflowed glue is carefully cleaned. The bandpass filter 503 is bonded to the other side of the detector frame 502 after the glue layer is cured, and a detector cover 505 is provided on the outside of the first spectral detector assembly 5.

[0052] See also Fig.12The first spectral detector assembly 5 is fixed on the focal plane bracket 1 through the detector adjustment pad 504 and fixed by screws. The front and back and inclination of the target surface of the array detector 501 in the first spectral detector assembly 5 are adjusted by grinding the thickness and inclination of the detector adjustment pad 504; the detector adjustment pad 504 is a double-sided double-boss structure, the coplanarity of the double boss is better than 0.003mm, and the parallelism of the two sides is better than 0.005mm. The boss area is given a minimum requirement value according to the heat conduction requirements after thermal design analysis, which reduces the difficulty of manual grinding.

[0053] The focal plane assembly also includes a reference quasi-cubic mirror assembly arranged on the second reference plane 103. The reference cubic mirror assembly 11 is a cube with a side length of 14 mm, whose I surface is parallel to the first reference plane 101 of the focal plane bracket 1, and whose II surface is parallel to the second reference plane 103 of the focal plane bracket 1. The installation error is better than 3". The reference cubic mirror assembly 11 is used to quickly align with the camera coordinate system when the hyperspectral focal plane is integrated with the lens.

[0054] After assembly, the array hyperspectral focal plane assembly must undergo sinusoidal and random vibration tests (the magnitude of which refers to the given satellite construction specifications) and vacuum high and low temperature cycle tests (the temperature range is based on the on-orbit operating temperature ±20°C) to eliminate installation and bonding stresses and ensure the long-term stability of the spliced ​​focal plane.

Claims

1. A focal plane assembly of a spatial array hyperspectral camera, characterized in that: include: A focal plane bracket (1), wherein the focal plane bracket (1) is provided with a first reference plane (101), a first parallel plane (102), a second reference plane (103), a component mounting surface (104), a glue injection hole (105) and a prefabricated pin hole (106); the first parallel plane (102) and the first reference plane (101) are in a bilaterally symmetrical relationship, the coplanarity is better than 0.003 mm, the parallelism with the first reference plane (101) is better than 0.005 mm, the perpendicularity between the second reference plane (103) and the first reference plane (101) is better than 0.005 mm; the perpendicularity between the component mounting surface (104) and the first reference plane (101) is better than 0.01 mm; A dichroic mirror assembly (2) is positioned and mounted on an internal assembly mounting surface (104) of a focal plane support (1) through a prefabricated pin hole (106); the dichroic mirror (201) of the dichroic mirror assembly (2) is coated with a dichroic film and an anti-reflection film on both sides, with a reflection band of 450nm to 600nm and a transmission band of 600nm to 860nm; A first beam splitter reflector assembly (3) and a second beam splitter reflector assembly (4) are installed in the focal plane support (1) and are positioned by injection molding through the injection hole (105), and the first beam splitter reflector assembly (3) and the second beam splitter reflector assembly (4) respectively receive reflected light and transmitted light of the dichroic mirror assembly (2); Four groups of spectral detector assemblies with identical structures are installed on the first reference plane (101) and the first parallel plane (102), namely, a first spectral detector assembly (5), a second spectral detector assembly (6), a third spectral detector assembly (7) and a fourth spectral detector assembly (8), wherein the first spectral detector assembly (5) and the second spectral detector assembly (6) are symmetrical relative to the first beam splitter reflector assembly (3), and the third spectral detector assembly (7) and the fourth spectral detector assembly (8) are symmetrical relative to the second beam splitter reflector assembly (4); and a dust cover (9) arranged on the upper end of the focal plane support (1); The incident light irradiates the dichroic mirror (201) of the dichroic mirror assembly (2); the light reflected by the dichroic mirror (201) is split by the first beam splitting reflector assembly (3) and then irradiates the first spectrum image plane (506) of the first spectrum detector assembly (5) and the second spectrum image plane (601) of the second spectrum detector assembly (6); the light transmitted by the dichroic mirror (201) is split by the second beam splitting reflector assembly (4) and then irradiates the third spectrum image plane (701) of the third spectrum detector assembly (7) and the fourth spectrum image plane (801) of the fourth spectrum detector assembly (8).

2. The focal plane assembly of a spatial array hyperspectral camera according to claim 1, characterized in that: The focal plane support (1) is made of Invar steel, and its linear expansion coefficient is customized to be ≤0.6×10 -6 .

3. The focal plane assembly of a spatial array hyperspectral camera according to claim 1, characterized in that: The first reference surface (101) of the focal plane bracket (1) is composed of four coplanar rectangular bosses, with a coplanarity better than 0.003 mm; the second reference surface (103) has a flatness better than 0.003 mm, and the component mounting surface (104) has a flatness better than 0.003 mm.

4. The focal plane assembly of a spatial array hyperspectral camera according to claim 1, characterized in that: The diameter of the glue injection hole (105) is Φ2.5 mm, and optical epoxy glue is injected into the mounting interface corresponding to the first beam splitter reflector assembly (3) and the second beam splitter reflector assembly (4) and the focal plane bracket (1) through the glue injection hole (105) for bonding, curing and positioning; the diameter of the prefabricated pin hole (106) is Φ2.8 mm, and the pin is connected and positioned with the dichroic mirror assembly (2) through the prefabricated pin hole (106) on the focal plane bracket (1).

5. The focal plane assembly of a spatial array hyperspectral camera according to claim 1, characterized in that: The dichroic mirror assembly (2) comprises a dichroic mirror (201), a dichroic mirror frame (202), a thin-sheet flexible structure (203) and a dichroic mirror adjustment pad (204); the dichroic mirror (201) and the dichroic mirror frame (202) are bonded and assembled; the thin-sheet flexible structure (203) and the dichroic mirror adjustment pad (204) are sequentially arranged between the dichroic mirror frame (202) and the assembly mounting surface (104) inside the focal plane bracket (1); the adhesive between the dichroic mirror (201) and the dichroic mirror frame (202) is an optical epoxy glue; the dichroic mirror (201) is made of quartz glass with a minimum thickness of 4 mm and a surface root mean square value better than 12 nm; the dichroic mirror frame (202) is made of invar with a linear expansion coefficient customized to be ≤0.6×10 -6 The thin sheet type flexible structure (203) includes two sheets.

6. The focal plane assembly of a spatial array hyperspectral camera according to claim 1, characterized in that: The first beam splitter reflector assembly (3) is composed of a first beam splitter reflector (301) and a base (302); a cylindrical boss is machined on the bottom of the first beam splitter reflector (301); the cylindrical surface is a bonding surface; the cylindrical surface of the first beam splitter reflector (301) is bonded and fixed to the base (302) via three flexible structures (303) evenly distributed around the circumference; the first beam splitter reflector (301) is made of microcrystalline glass; the verticality of the two reflection surfaces of the first beam splitter reflector (301) is better than 0.005 mm, and the surface shape is better than 12 nm; the base (302) is made of invar, and the linear expansion coefficient is customized to be ≤0.6×10 -6 .

7. The focal plane assembly of a spatial array hyperspectral camera according to claim 1, characterized in that: The first spectrum detector assembly (5) and the second spectrum detector assembly (6) correspond to a detection spectrum range of 450nm to 600nm, and the third spectrum detector assembly (7) and the fourth spectrum detector assembly (8) correspond to a detection spectrum range of 600nm to 860nm.

8. The focal plane assembly of a spatial array hyperspectral camera according to claim 1, characterized in that: The first spectrum detector assembly (5), the second spectrum detector assembly (6), the third spectrum detector assembly (7) and the fourth spectrum detector assembly (8) have the same structure and are connected to the focal plane bracket (1) in the same manner; the first spectrum detector assembly (5) is composed of a planar array detector (501), a detector frame (502) and a bandpass filter (503); the detector frame (502) is processed with a rectangular groove, the planar array detector (501) is installed in the rectangular groove of the detector frame (502), and the size of the rectangular groove is 0.05mm to 0.1mm larger than the outer size of the detector on one side; during installation, the planar array detector (501) is evenly coated with thermal conductive glue around the periphery and then embedded in the rectangular groove of the detector frame (502); the bandpass filter (503) is bonded to the other side of the detector frame (502) after the glue layer is cured; and a detector cover (505) is arranged on the outside of the first spectrum detector assembly (5).

9. The focal plane assembly of a spatial array hyperspectral camera according to claim 1, characterized in that: The first spectral detector assembly (5) is fixed to the focal plane bracket (1) via a detector adjustment pad (504), and the front and back and tilt of the target surface of the surface array detector (501) in each group of spectral detector assemblies (4) are adjusted by adjusting the thickness and tilt angle of the detector adjustment pad (504); the detector adjustment pad (504) is a double-sided double-convex structure, the coplanarity of the double-convex is better than 0.003 mm, and the parallelism of the two sides is better than 0.005 mm.

10. The focal plane assembly of a spatial array hyperspectral camera according to any one of claims 1 to 9, characterized in that: The focal plane assembly further comprises a reference quasi-cubic mirror assembly arranged on the second reference plane (103). The reference cubic mirror assembly (11) is a cube with a side length of 14 mm, whose surface I is parallel to the first reference plane (101) of the focal plane bracket (1), and whose surface II is parallel to the second reference plane (103) of the focal plane bracket (1), and whose installation errors are both better than 3″. The reference cubic mirror assembly (11) is used to quickly align the hyperspectral focal plane with the camera coordinate system when the lens is integrated.

Images