Compact off-axis reflection type three-waveband multifunctional common-caliber optical system

Abstract

The invention discloses a compact off-axis reflection type three-waveband multifunctional common-caliber optical system. Belongs to the technical field of photoelectricity, and particularly relates to the technical field of compact off-axis reflection type three-waveband common-caliber photoelectricity. The laser, short-wave infrared and medium-wave infrared common aperture and laser emission and receiving integrated optical design are realized, and the target detection, positioning aiming and laser guiding performance of the system is improved. The system comprises an off-axis reflection type afocal objective lens, a laser emission light path, a short-wave imaging light path and a medium-wave imaging light path, a laser beam emitted by a laser emission light path is emitted to a target through an off-axis reflection type afocal objective lens, the target reflects the laser beam and a short-wave infrared beam to the off-axis reflection type afocal objective lens, and meanwhile, the target radiates a medium-wave infrared beam to the off-axis reflection type afocal objective lens; the off-axis reflection type afocal objective reflects the laser beam and the short-wave infrared beam to the short-wave imaging light path for imaging, and the off-axis reflection type afocal objective reflects the medium-wave infrared beam to the medium-wave imaging light path for imaging.

Description

Technical Field

[0001] The invention belongs to the field of optoelectronic technology, and in particular relates to the field of compact off-axis reflective three-band common aperture optoelectronic technology. Background Art

[0002] With the rapid advancement of science and technology and the increasingly complex application environment, many fields such as military reconnaissance, camouflage identification, environmental monitoring, geological exploration, etc. have put forward higher requirements for the comprehensiveness and accuracy of information acquisition. In these fields, the limitation of single-band imaging that can only reflect one aspect of the physical characteristics of the target has become increasingly prominent and it is difficult to meet the diverse actual needs.

[0003] In different spectral bands, the optical characteristics of the target vary significantly. Based on this, multi-band image fusion technology came into being. By integrating image information from multiple bands, it is possible to achieve a more accurate and comprehensive understanding of the target and achieve all-weather, wide-coverage, and high-resolution target observation. For example, medium-wave infrared can accurately detect and identify targets at night by detecting the temperature difference between the target and the background; short-wave infrared has the unique ability to penetrate smoke and can obtain clear image details in complex environments, providing strong support for accurate analysis; lasers can not only achieve precise aiming and guidance of targets, but short-wave infrared can also detect laser spots with wavelengths within the short-wave band. The organic combination of the three can efficiently obtain the shape, orientation, and motion form information of distant targets.

[0004] In order to meet the needs of long-distance target detection, increasing the aperture and focal length of the optical system has become an inevitable choice, and large-aperture, multi-band, lightweight and miniaturized optoelectronic payloads have therefore become the current development direction. As a common multi-band imaging solution, the split-aperture imaging system simply combines multiple independent single-band optical systems together. However, this imaging system has many disadvantages due to its distributed structure, such as its large size and great difficulty in achieving miniaturization and lightness, which seriously affects the mobility of the system and greatly limits its application areas, making it difficult to directly apply it to military reconnaissance, camouflage identification, environmental monitoring, geological exploration and other fields that have strict requirements on equipment performance and imaging quality. It also increases the difficulty of operation for users. Summary of the invention

[0005] In order to solve the problem that the existing divided-aperture optical system is difficult to miniaturize and lighten, the present invention provides a compact off-axis reflective three-band multifunctional common-aperture optical system, which adopts an off-axis reflective afocal objective lens with a rear optical path structure to achieve a common aperture of laser, short-wave infrared, and medium-wave infrared, as well as an integrated optical design of laser emission and reception, thereby improving the system's target detection, positioning and aiming, and laser guidance performance.

[0006] The compact off-axis reflective three-band multifunctional common aperture optical system comprises: an off-axis reflective afocal objective lens, a laser emission optical path, a short-wave imaging optical path and a medium-wave imaging optical path;

[0007] The laser emission optical path emits a laser beam through an off-axis reflective afocus objective lens to a target, the target reflects the laser beam and a short-wave infrared beam to the off-axis reflective afocus objective lens, and at the same time the target radiates a medium-wave infrared beam to the off-axis reflective afocus objective lens, the off-axis reflective afocus objective lens reflects the laser beam and the short-wave infrared beam to the short-wave imaging optical path for imaging, and the off-axis reflective afocus objective lens reflects the medium-wave infrared beam to the medium-wave imaging optical path for imaging;

[0008] The off-axis reflective afocal objective lens includes: a primary mirror, a secondary mirror, a folding mirror and a third mirror;

[0009] The laser emission optical path includes: a laser light source, a laser collimation and beam expansion component, a second beam splitter and a first beam splitter;

[0010] The short-wave imaging optical path includes: a first beam splitter, a second beam splitter, a short-wave infrared imaging component and a short-wave infrared detector target surface;

[0011] The medium-wave imaging optical path includes: a first beam splitter, a medium-wave infrared imaging component and a medium-wave infrared detector target surface.

[0012] Furthermore, in the laser emission optical path, the laser light beam emitted by the laser light source passes through the laser collimation and beam expansion component, the second beam splitter and the first beam splitter in sequence and then is emitted, and the output light of the laser emission optical path is emitted into the three mirrors.

[0013] Furthermore, in the laser collimation and beam expansion assembly, the incident light beam passes through: a first laser collimation and beam expansion lens, a second laser collimation and beam expansion lens, a third laser collimation and beam expansion lens, a fourth laser collimation and beam expansion lens, a fifth laser collimation and beam expansion lens, a sixth laser collimation and beam expansion lens, and a seventh laser collimation and beam expansion lens in sequence;

[0014] The first laser collimation and beam expansion lens, the fourth laser collimation and beam expansion lens, the sixth laser collimation and beam expansion lens and the seventh laser collimation and beam expansion lens are meniscus spherical lenses with positive optical focal length; the second laser collimation and beam expansion lens and the fifth laser collimation and beam expansion lens are biconcave spherical lenses with negative optical focal length; the third laser collimation and beam expansion lens is a biconvex spherical lens with positive optical focal length.

[0015] Furthermore, the off-axis reflective afocal objective lens includes an off-axis output light path and an off-axis incident light path; in the off-axis output light path, after the laser light beam enters the three mirrors, it passes through the folding mirror, the secondary mirror and the primary mirror in sequence and then exits to the target; in the off-axis incident light path, the laser light beam, the short-wave infrared light beam and the medium-wave infrared light beam received by the primary mirror pass through the secondary mirror, the folding mirror and the third mirror in sequence and then exit, and the output light of the off-axis incident light path enters the first beam splitter; the materials of the primary mirror, the secondary mirror, the folding mirror and the third mirror are microcrystals; the image-side focal points of the primary mirror and the secondary mirror coincide with the object-side focal points of the three mirrors; the folding mirror is placed at 45° to the horizontal plane.

[0016] Furthermore, in the short-wave imaging optical path, the laser beam and the short-wave infrared beam are reflected by the first beam splitter, and then separated into a laser beam and a short-wave infrared beam by the second beam splitter. The short-wave infrared beam is then emitted to the target surface of the short-wave infrared detector for imaging through the short-wave infrared imaging component; the laser beam is emitted into the laser light source;

[0017] The first beam splitter is arranged between the off-axis reflective afocal objective lens and the medium-wave infrared imaging component in the longitudinal direction, and is used to decompose the incident light beam into a medium-wave infrared beam, a short-wave infrared beam and a laser beam. The first beam splitter is used to transmit the medium-wave infrared beam and reflect the short-wave infrared beam and the laser beam; the second beam splitter is arranged between the first beam splitter and the short-wave infrared imaging component in the transverse direction, and the second beam splitter is used to decompose the incident light beam into a short-wave infrared beam and a laser beam. The second beam splitter is used to transmit the short-wave infrared beam and reflect the laser beam; the first beam splitter is placed at 45° to the horizontal plane; the second beam splitter is placed at 45° to the vertical plane.

[0018] Furthermore, in the short-wave infrared imaging assembly, the incident light beam passes through: a short-wave infrared first reflector, a short-wave infrared first cemented lens, a short-wave infrared second cemented lens, a short-wave infrared first lens, a short-wave infrared second lens and a short-wave infrared second reflector in sequence;

[0019] The short-wave infrared first glued lens comprises: a short-wave infrared first glued lens 1 and a short-wave infrared first glued lens 2; the short-wave infrared second glued lens comprises a short-wave infrared second glued lens 1 and a short-wave infrared second glued lens 2.

[0020] Furthermore, it is characterized in that, in the medium-wave imaging optical path, the medium-wave infrared light beam is transmitted through the first beam splitter and then emitted into the medium-wave infrared detector target surface through the medium-wave infrared imaging component for imaging.

[0021] Furthermore, in the medium-wave infrared imaging assembly, the incident light beam sequentially passes through: a medium-wave infrared first lens, a medium-wave infrared second lens, a medium-wave infrared first reflector, a medium-wave infrared third lens, a medium-wave infrared second reflector, a medium-wave infrared fourth lens, a medium-wave infrared fifth lens, a medium-wave infrared sixth lens, a medium-wave infrared detector window, and a medium-wave infrared detector filter;

[0022] The first medium-wave infrared lens, the fourth medium-wave infrared lens and the sixth medium-wave infrared lens are meniscus spherical lenses with positive optical power, the second medium-wave infrared lens and the fifth medium-wave infrared lens are meniscus spherical lenses with negative optical power, the first medium-wave infrared reflector and the second medium-wave infrared reflector are both plane reflectors placed at 45° to the vertical plane, and the third medium-wave infrared lens is a meniscus aspherical lens with positive optical power.

[0023] Furthermore, the wavelength of the medium-wave infrared light beam is 3 to 5 microns; the wavelength of the short-wave infrared light beam is 0.9 to 1.7 microns; and the wavelength of the laser light beam is 0.9 to 1.7 microns.

[0024] The beneficial effects of the method of the present invention are:

[0025] (1) The present invention adopts an off-axis reflective afocal objective lens with a rear optical path structure to achieve the effect of laser, short-wave infrared and medium-wave infrared common aperture. This design can not only accurately observe and image the target in day and night environments, but also successfully realizes the exquisite optical design of integrated laser emission and reception, greatly improving the system's performance in target detection, positioning and aiming, and laser guidance.

[0026] (2) As a total reflection optical system, the off-axis reflective afocal objective has incomparable advantages. It does not have the problem of occlusion, completely eliminates the dispersion problem, has the highest transfer function value at the theoretical design level, and can ensure the best imaging quality. This feature can not only effectively reduce the volume of the system and make its structure more compact, but also greatly improve the maneuverability and significantly improve the system integration. The off-axis reflective afocal objective + rear optical path structure have perfect imaging characteristics and constitute an independent module, which can simplify the design, processing and manufacturing process. With these advantages, the present invention enables the system to have the excellent ability of multi-platform collaborative target detection and multi-task collaborative operations, bringing new possibilities for applications in related fields.

[0027] (3) Compared with the coaxial catadioptric optical path design, the off-axis reflective afocal objective lens has no chromatic aberration in its total reflection optical system. The off-axis aperture also avoids the problem of light obstruction. The entire system has a compact structure, thereby achieving miniaturization and lightweight of the optical system. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1is a structural diagram of the system of the present invention;

[0029] Figure 2 This is a structural diagram of the medium-wave infrared imaging component of the present invention;

[0030] Figure 3 This is a structural diagram of the laser collimation and beam expansion assembly of the present invention;

[0031] Figure 4 This is a structural diagram of the short-wave infrared imaging component of the present invention.

[0032] L1-primary mirror, L2-secondary mirror, L3-folding mirror, L4-third mirror, L5-first spectroscope, L6-MWIR imaging assembly, L61-MWIR first lens, L62-MWIR second lens, L63-MWIR first reflector, L64-MWIR third lens, L65-MWIR second reflector, L66-MWIR fourth lens, L67-MWIR fifth lens, L68-MWIR sixth lens, L69-MWIR detector window, L610-MWIR detector filter, L7-second spectroscope, L8-laser collimation and beam expansion assembly, L81-laser collimation and beam expansion first lens, L82-laser collimation and beam expansion second lens, L83-laser collimation and beam expansion third lens, L84-laser The fourth lens for light collimation and beam expansion, L85-the fifth lens for laser collimation and beam expansion, L86-the sixth lens for laser collimation and beam expansion, L87-the seventh lens for laser collimation and beam expansion, L9-short-wave infrared imaging component, L91-the first reflector for short-wave infrared, L92-the first cemented lens for short-wave infrared, L93-the second cemented lens for short-wave infrared, L94-the first lens for short-wave infrared, L95-the second lens for short-wave infrared, L96-the second reflector for short-wave infrared, L921-the first cemented lens for short-wave infrared, L922-the first cemented lens for short-wave infrared, L931-the second cemented lens for short-wave infrared, L932-the second cemented lens for short-wave infrared, S1-the target surface of medium-wave infrared detector, S2-the laser light source, S3-the target surface of short-wave infrared detector. DETAILED DESCRIPTION

[0033] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the protection scope of the present invention.

[0034] This embodiment provides a compact off-axis reflective three-band multifunctional common aperture optical system. Figure 1 As shown, the system includes: an off-axis reflective afocal objective lens, a laser emission optical path, a short-wave imaging optical path and a medium-wave imaging optical path.

[0035] The laser emission optical path emits a laser beam through an off-axis reflective afocus objective lens to a target, the target reflects the laser beam and a short-wave infrared beam to the off-axis reflective afocus objective lens, and at the same time the target radiates a medium-wave infrared beam to the off-axis reflective afocus objective lens, the off-axis reflective afocus objective lens reflects the laser beam and the short-wave infrared beam to the short-wave imaging optical path for imaging, and the off-axis reflective afocus objective lens reflects the medium-wave infrared beam to the medium-wave imaging optical path for imaging.

[0036] The combination of the off-axis reflective afocal objective lens and the laser emission optical path makes the laser emission optical path have the advantages of simple structure, high beam expansion ratio and compact space volume.

[0037] The combination of the off-axis reflective afocal objective lens and the short-wave imaging optical path enables the short-wave imaging optical path to realize both the detection of the laser spot and the imaging of the short-wave infrared beam.

[0038] The off-axis reflective afocal objective lens includes: a primary mirror L1, a secondary mirror L2, a folding mirror L3 and a third mirror L4.

[0039] The primary mirror L1 reflects the incident light, and its reflecting surface is a concave aspheric surface; the secondary mirror L2 reflects the incident light, and its reflecting surface is a convex aspheric surface; the folding mirror L3 reflects the incident light, and its reflecting surface is a flat surface; the tertiary mirror L4 reflects the incident light, and its reflecting surface is a concave aspheric surface, and the reflected light is parallel light.

[0040] The laser emission optical path includes: a laser light source S2, a laser collimating and beam expanding assembly L8, a second beam splitter L7 and a first beam splitter L5.

[0041] The laser collimating and beam expanding component L8 and the laser light source S2 are arranged on the reflection light path of the second beam splitter L7; the laser light source S2 is a fiber optic light source for emitting a laser beam; the laser collimating and beam expanding component L8 is used to compress the divergence angle of the laser beam emitted by the laser light source S2.

[0042] The short-wave imaging optical path includes: a first beam splitter L5, a second beam splitter L7, a short-wave infrared imaging component L9 and a short-wave infrared detector target surface S3.

[0043] The short-wave infrared imaging component L9 and the short-wave infrared detector target surface S3 are arranged on the transmission light path of the second beam splitter L7; the short-wave infrared imaging component L9 is used to image the short-wave infrared light beam on the short-wave infrared detector target surface S3.

[0044] The laser collimation and beam expansion component L8 and the short-wave infrared imaging component L9 both use domestic glass spherical lenses. This configuration enables the present invention to not only ensure the high yield advantage of processing and assembly and reduce costs, but also ensure the high reliability of the product.

[0045] The medium-wave imaging optical path includes: a first beam splitter L5, a medium-wave infrared imaging component L6 and a medium-wave infrared detector target surface S1.

[0046] In the laser emission optical path, the laser light beam emitted by the laser light source S2 passes through the laser collimating beam expanding assembly L8, the second beam splitter L7 and the first beam splitter L5 in sequence and then is emitted, and the output light of the laser emission optical path is emitted into the three mirrors L4.

[0047] like Figure 3 As shown, in the laser collimation and beam expansion assembly L8, the laser light beam emitted by the laser light source S2 passes through: the first laser collimation and beam expansion lens L81, the second laser collimation and beam expansion lens L82, the third laser collimation and beam expansion lens L83, the fourth laser collimation and beam expansion lens L84, the fifth laser collimation and beam expansion lens L85, the sixth laser collimation and beam expansion lens L86 and the seventh laser collimation and beam expansion lens L87 in sequence.

[0048] The first laser collimation and beam expansion lens L81, the fourth laser collimation and beam expansion lens L84, the sixth laser collimation and beam expansion lens L86 and the seventh laser collimation and beam expansion lens L87 are meniscus spherical lenses with positive optical focal length; the second laser collimation and beam expansion lens L82 and the fifth laser collimation and beam expansion lens L85 are biconcave spherical lenses with negative optical focal length; the third laser collimation and beam expansion lens L83 is a biconvex spherical lens with positive optical focal length.

[0049] The off-axis reflective afocal objective lens includes an off-axis output light path and an off-axis incident light path; in the off-axis output light path, after the laser beam enters the three mirrors L4, it passes through the folding mirror L3, the secondary mirror L2 and the main mirror L1 in sequence and then exits to the target; in the off-axis incident light path, the laser beam, the short-wave infrared beam and the medium-wave infrared beam received by the main mirror L1 pass through the secondary mirror L2, the folding mirror L3 and the three mirrors L4 in sequence and then exit, and the output light of the off-axis incident light path enters the first beam splitter L5; the materials of the main mirror L1, the secondary mirror L2, the folding mirror L3 and the three mirrors L4 are microcrystals, so the off-axis reflective afocal objective lens has the advantages of high and low temperature resistance and a small thermal expansion coefficient; the image side focus of the main mirror L1 and the secondary mirror L2 coincides with the object side focus of the three mirrors L4; the folding mirror L3 is placed at 45° to the horizontal plane.

[0050] In the short-wave imaging optical path, the laser beam and the short-wave infrared beam are reflected by the first beam splitter L5, and then separated into a laser beam and a short-wave infrared beam by the second beam splitter L7. The short-wave infrared beam is then emitted to the short-wave infrared detector target surface S3 for imaging through the short-wave infrared imaging component L9; the laser beam is emitted into the laser light source S2; and the short-wave infrared imaging component L9 independently completes the imaging.

[0051] The reflection surface and the transmission surface of the first beam splitter L5 are both planes. The first beam splitter L5 is arranged between the off-axis reflective afocal objective lens and the medium-wave infrared imaging component L6 in the longitudinal direction, and is used to decompose the incident light beam into a medium-wave infrared beam, a short-wave infrared beam and a laser beam. The first beam splitter L5 is used to transmit the medium-wave infrared beam and reflect the short-wave infrared beam and the laser beam.

[0052] The reflection surface and the transmission surface of the second beam splitter L7 are both planes. The second beam splitter L7 is arranged laterally between the first beam splitter L5 and the short-wave infrared imaging component L9. The second beam splitter L7 is used to decompose the incident light beam into a short-wave infrared beam and a laser beam. The second beam splitter L7 is used to transmit the short-wave infrared beam and reflect the laser beam. The first beam splitter L5 is placed at 45° to the horizontal plane; the second beam splitter L7 is placed at 45° to the vertical plane.

[0053] like Figure 4 As shown, in the short-wave infrared imaging component L9, the incident light beam passes through: a short-wave infrared first reflector L91, a short-wave infrared first cemented lens L92, a short-wave infrared second cemented lens L93, a short-wave infrared first lens L94, a short-wave infrared second lens L95 and a short-wave infrared second reflector L96 in sequence.

[0054] The short-wave infrared first cemented lens L92 includes: a short-wave infrared first cemented lens 1 L921 and a short-wave infrared first cemented lens 2 L922; the short-wave infrared second cemented lens L93 includes a short-wave infrared second cemented lens 1 L931 and a short-wave infrared second cemented lens 2 L932.

[0055] In the medium-wave imaging optical path, the medium-wave infrared light beam is transmitted through the first beam splitter L5 and then incident on the medium-wave infrared detector target surface S1 through the medium-wave infrared imaging component L6 for imaging; the medium-wave infrared imaging component L6 independently completes the imaging.

[0056] The medium-wave infrared imaging component L6 and the short-wave infrared imaging component L9 independently improve the imaging design, making it easy to realize the integrated design and simultaneous imaging of short-wave and medium-wave infrared.

[0057] like Figure 2As shown, the medium-wave infrared imaging component L6 is arranged on the transmission light path of the first beam splitter L5, so as to image the medium-wave infrared light beam on the target surface S1 of the medium-wave infrared detector; in the medium-wave infrared imaging component L6, the incident light beam passes through in sequence: the first medium-wave infrared lens L61, the second medium-wave infrared lens L62, the first medium-wave infrared reflector L63, the third medium-wave infrared lens L64, the second medium-wave infrared reflector L65, the fourth medium-wave infrared lens L66, the fifth medium-wave infrared lens L67, the sixth medium-wave infrared lens L68, the medium-wave infrared detector window L69 and the medium-wave infrared detector filter L610;

[0058] The medium-wave infrared first lens L61, the medium-wave infrared fourth lens L66 and the medium-wave infrared sixth lens L68 are meniscus spherical lenses with positive focal length, the medium-wave infrared second lens L62 and the medium-wave infrared fifth lens L67 are meniscus spherical lenses with negative focal length, the medium-wave infrared first reflector L63 and the medium-wave infrared second reflector L65 are both plane reflectors placed at 45° to the vertical plane, and the medium-wave infrared third lens L64 is a meniscus aspherical lens with positive focal length; the medium-wave infrared first lens L61, the medium-wave infrared second lens L62, the medium-wave infrared third lens L64, the medium-wave infrared fourth lens L66, the medium-wave infrared fifth lens L67, the medium-wave infrared sixth lens L68, the medium-wave infrared detector window L69 and the medium-wave infrared detector filter L610 are made of single crystal silicon and single crystal germanium.

[0059] The placement of the deflecting mirror L3, the first beam splitter L5, the second beam splitter L7, the first medium-wave infrared reflector L63 and the second medium-wave infrared reflector L65 can not only deflect the light by changing the transmission angle of the light, but also reduce the spatial volume of the system.

[0060] The material of the medium-wave infrared first reflector L63 and the medium-wave infrared second reflector L65 is domestically produced H-K9L glass.

[0061] The medium-wave infrared imaging component L6 adopts a secondary imaging structure, with imaging quality close to the diffraction limit and achieving 100% cold stop matching.

[0062] The wavelength of the medium-wave infrared light beam is 3 to 5 microns. With such an arrangement, the present invention can realize uninterrupted imaging day and night and is not easily detected by enemy reconnaissance.

[0063] The wavelength of the short-wave infrared light beam is 0.9 to 1.7 microns; the wavelength of the laser light beam is 0.9 to 1.7 microns. With such an arrangement, the present invention enables the short-wave infrared imaging optical path to realize target detection and imaging while also realizing observation of the laser spot.

Claims

1. A compact off-axis reflective three-band multifunctional common aperture optical system, characterized in that: The system comprises: an off-axis reflective afocal objective lens, a laser emission optical path, a short-wave imaging optical path and a medium-wave imaging optical path; The laser emission optical path emits a laser beam through an off-axis reflective afocus objective lens to a target, the target reflects the laser beam and a short-wave infrared beam to the off-axis reflective afocus objective lens, and at the same time the target radiates a medium-wave infrared beam to the off-axis reflective afocus objective lens, the off-axis reflective afocus objective lens reflects the laser beam and the short-wave infrared beam to the short-wave imaging optical path for imaging, and the off-axis reflective afocus objective lens reflects the medium-wave infrared beam to the medium-wave imaging optical path for imaging; The off-axis reflective afocal objective lens includes: a primary mirror (L1), a secondary mirror (L2), a folding mirror (L3) and a third mirror (L4); The laser emission optical path comprises: a laser light source (S2), a laser collimation and beam expansion component (L8), a second beam splitter (L7) and a first beam splitter (L5); The short-wave imaging optical path includes: a first beam splitter (L5), a second beam splitter (L7), a short-wave infrared imaging component (L9) and a short-wave infrared detector target surface (S3); The medium-wave imaging optical path comprises: a first beam splitter (L5), a medium-wave infrared imaging component (L6) and a medium-wave infrared detector target surface (S1).

2. The compact off-axis reflective three-band multifunctional common aperture optical system according to claim 1, characterized in that: In the laser emission optical path, the laser light beam emitted by the laser light source (S2) passes through the laser collimation and beam expansion component (L8), the second beam splitter (L7) and the first beam splitter (L5) in sequence before being emitted, and the output light of the laser emission optical path is emitted into the three mirrors (L4).

3. The compact off-axis reflective three-band multifunctional common aperture optical system according to claim 2, characterized in that: In the laser collimation and beam expansion assembly (L8), the incident light beam passes through: a first laser collimation and beam expansion lens (L81), a second laser collimation and beam expansion lens (L82), a third laser collimation and beam expansion lens (L83), a fourth laser collimation and beam expansion lens (L84), a fifth laser collimation and beam expansion lens (L85), a sixth laser collimation and beam expansion lens (L86) and a seventh laser collimation and beam expansion lens (L87) in sequence; The first laser collimation and beam expansion lens (L81), the fourth laser collimation and beam expansion lens (L84), the sixth laser collimation and beam expansion lens (L86) and the seventh laser collimation and beam expansion lens (L87) are meniscus spherical lenses with positive optical focal length; the second laser collimation and beam expansion lens (L82) and the fifth laser collimation and beam expansion lens (L85) are biconcave spherical lenses with negative optical focal length; and the third laser collimation and beam expansion lens (L83) is a biconvex spherical lens with positive optical focal length.

4. The compact off-axis reflective three-band multifunctional common aperture optical system according to claim 1, characterized in that: The off-axis reflective afocal objective lens comprises an off-axis emission light path and an off-axis incident light path; in the off-axis emission light path, after a laser beam enters a third mirror (L4), it passes through a folding mirror (L3), a secondary mirror (L2) and a primary mirror (L1) in sequence and then exits to a target; in the off-axis incident light path, a laser beam, a short-wave infrared beam and a medium-wave infrared beam received by the primary mirror (L1) pass through the secondary mirror (L2), the folding mirror (L3) and the third mirror (L4) in sequence and then exit, and the emission light of the off-axis incident light path enters a first beam splitter (L5); the material of the primary mirror (L1), the secondary mirror (L2), the folding mirror (L3) and the third mirror (L4) is microcrystal; the image-side focal points of the primary mirror (L1) and the secondary mirror (L2) coincide with the object-side focal points of the third mirror (L4); and the folding mirror (L3) is placed at 45 degrees to a horizontal plane.

5. The compact off-axis reflective three-band multifunctional common aperture optical system according to claim 1, characterized in that: In the short-wave imaging optical path, the laser beam and the short-wave infrared beam are reflected by the first beam splitter (L5), and then separated into the laser beam and the short-wave infrared beam by the second beam splitter (L7). The short-wave infrared beam is then emitted to the short-wave infrared detector target surface (S3) for imaging through the short-wave infrared imaging component (L9); the laser beam is emitted into the laser light source (S2); The first beam splitter (L5) is arranged between the off-axis reflective afocal objective lens and the medium-wave infrared imaging component (L6) in the longitudinal direction, and is used to decompose the incident light beam into a medium-wave infrared beam, a short-wave infrared beam and a laser beam. The first beam splitter (L5) is used to transmit the medium-wave infrared beam and reflect the short-wave infrared beam and the laser beam. The second beam splitter (L7) is arranged between the first beam splitter (L5) and the short-wave infrared imaging component (L9) in the transverse direction, and is used to decompose the incident light beam into a short-wave infrared beam and a laser beam. The second beam splitter (L7) is used to transmit the short-wave infrared beam and reflect the laser beam. The first beam splitter (L5) is placed at an angle of 45 degrees to the horizontal plane; and the second beam splitter (L7) is placed at an angle of 45 degrees to the vertical plane.

6. The compact off-axis reflective three-band multifunctional common aperture optical system according to claim 5, characterized in that: In the short-wave infrared imaging component (L9), the incident light beam passes through: a short-wave infrared first reflector (L91), a short-wave infrared first cemented lens (L92), a short-wave infrared second cemented lens (L93), a short-wave infrared first lens (L94), a short-wave infrared second lens (L95) and a short-wave infrared second reflector (L96) in sequence; The short-wave infrared first cemented lens (L92) includes: a short-wave infrared first cemented lens 1 (L921) and a short-wave infrared first cemented lens 2 (L922); the short-wave infrared second cemented lens (L93) includes a short-wave infrared second cemented lens 1 (L931) and a short-wave infrared second cemented lens 2 (L932).

7. The compact off-axis reflective three-band multifunctional common aperture optical system according to claim 1, characterized in that: In the medium-wave imaging optical path, the medium-wave infrared light beam is transmitted through a first beam splitter (L5) and then emitted into a medium-wave infrared detector target surface (S1) through a medium-wave infrared imaging component (L6) to form an image.

8. The compact off-axis reflective three-band multifunctional common aperture optical system according to claim 7, characterized in that: In the medium-wave infrared imaging assembly (L6), the incident light beam passes through: a medium-wave infrared first lens (L61), a medium-wave infrared second lens (L62), a medium-wave infrared first reflector (L63), a medium-wave infrared third lens (L64), a medium-wave infrared second reflector (L65), a medium-wave infrared fourth lens (L66), a medium-wave infrared fifth lens (L67), a medium-wave infrared sixth lens (L68), a medium-wave infrared detector window (L69) and a medium-wave infrared detector filter (L610); The medium-wave infrared first lens (L61), the medium-wave infrared fourth lens (L66) and the medium-wave infrared sixth lens (L68) are meniscus spherical lenses with positive optical power, the medium-wave infrared second lens (L62) and the medium-wave infrared fifth lens (L67) are meniscus spherical lenses with negative optical power, the medium-wave infrared first reflector (L63) and the medium-wave infrared second reflector (L65) are both plane reflectors placed at 45 degrees to the vertical plane, and the medium-wave infrared third lens (L64) is a meniscus aspherical lens with positive optical power.

9. The compact off-axis reflective three-band multifunctional common aperture optical system according to claim 1, characterized in that: The wavelength of the medium-wave infrared light beam is 3 to 5 microns; the wavelength of the short-wave infrared light beam is 0.9 to 1.7 microns; and the wavelength of the laser light beam is 0.9 to 1.7 microns.

Images