An integrated optical system for field-of-view co-aperture imaging and laser beam expansion

Abstract

This invention provides an integrated optical system for field-of-view split-aperture imaging and laser beam expansion, belonging to the field of optoelectronic imaging technology. It includes a front-mounted common-aperture main optical system, comprising a primary mirror and a secondary mirror; an imaging branch located at the image side of the front-mounted common-aperture main optical system for receiving light signals from the target scene and focusing them; and a laser beam expansion branch located at the image side of the front-mounted common-aperture main optical system for expanding and emitting the input laser beam. This invention employs an integrated common-aperture split-aperture architecture to achieve a common optical path design for both focused and unfocused systems. It integrates focusing imaging and unfocused beam expansion optical paths with different focal lengths and field-of-view requirements under the same optical aperture, realizing the synergistic working capability of high-resolution imaging and high-magnification supercontinuum laser beam expansion.

Description

Technical Field

[0001] This invention belongs to the field of optoelectronic imaging technology, specifically an integrated optical system for field-of-view common aperture imaging and laser beam expansion. Background Technology

[0002] Existing space optical communication and high-resolution imaging payloads often employ a dual-aperture strapdown architecture. This design, by arranging two independent optical channels (high-resolution visible light imaging and supercontinuum laser beam expansion output) on the same platform, can, to a certain extent, guarantee the imaging and beam transmission performance of each channel. For example, the µLCTDual Aperture OHA space laser communication terminal developed by Space Micro employs an independent configuration of the imaging and transmission optical paths, resulting in a system dry mass of approximately 24.5 kg, significantly increasing the structural weight and volume. The main problems with this type of system are: a significant increase in system weight; and the near doubling of development costs due to the use of two sets of primary and secondary mirrors.

[0003] To reduce system weight and improve primary mirror utilization, some studies employ a common-aperture amplitude-splitting or spectroscopic architecture. This type of structure uses primary mirror amplitude-splitting, spectroscopic splitting, or polarization-splitting to allow different functional optical paths to operate in parallel within the same primary aperture. For example, in a ring-type common-aperture multiplexer, the imaging channel MTF@30 lp / mm is only about 0.25–0.35, which is insufficient for high-resolution imaging. Simultaneously, the beam splitter introduces additional wavefront errors, and the laser beam expander branch divergence angle remains within the 30–100 μrad range, making it difficult to achieve the requirements of high-coherence, long-distance optical links. Therefore, this architecture struggles to simultaneously achieve both high imaging quality and high-efficiency laser beam expanding capabilities within the same system. The main problems with this type of system are: the common aperture amplitude splitting architecture can only achieve serial operation of two optical path spectral bands, and cannot achieve parallel operation of high-resolution visible light imaging and supercontinuum laser beam expansion; in order to maintain imaging quality, it is necessary to increase the size of the primary mirror or add a correction mirror group, which violates the goal of lightweighting; after aperture splitting, the remote sensing imaging optical path only obtains part of the energy, resulting in a decrease in the signal-to-noise ratio of the imaging branch and limited spatial resolution.

[0004] In some applications of orbital rendezvous measurement and space optical links, a completely separate architecture is still used, where the imaging system and laser beam expander are independent. For example, the SOTA (SOCRATES) satellite payload developed by NICT in Japan has the imaging camera and laser communication telescope installed independently. The total payload mass of this system is 5.9 kg, and the divergence angle of the laser communication terminal is approximately 92 μrad. Because the optical axes of the two optical systems are separated, attitude control and software compensation are required to achieve optical path pointing consistency, resulting in increased system weight and low integration. The main problems with this type of structure are: the two complete optical systems double in size and mass, making it difficult to meet the miniaturization and lightweight requirements of modern optical communication and space exploration equipment; the low integration level makes it impossible to achieve high-resolution imaging and high-magnification laser beam expansion simultaneously in the same system; and the high cost, as the dual optical path uses two sets of primary and secondary mirrors, nearly doubling the development cost and increasing manufacturing, assembly, and maintenance costs. Summary of the Invention

[0005] To address the shortcomings of the prior art, the technical problem to be solved by the embodiments of the present invention is to provide an integrated optical system for field-of-view common aperture imaging and laser beam expansion.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0007] An integrated optical system for field-of-view common-aperture imaging and laser beam expansion includes:

[0008] A front-mounted common-aperture primary optical system, the front-mounted common-aperture primary optical system comprising a primary mirror and a secondary mirror;

[0009] An imaging branch is set at the image side of the front common-aperture main optical system for receiving light signals from the target scene and performing focused imaging.

[0010] A laser beam expander branch is located at the image side of the front common aperture main optical system for expanding and emitting the input laser beam;

[0011] The front common aperture main optical system divides the optical field of view, with the optical path of the main field of view being guided to the imaging branch and the optical path of the off-field field of view being guided to the laser beam expander branch.

[0012] As a further improvement: the imaging branch is a coaxial catadioptric focal system, including a plane mirror, a first positive meniscus lens, a second positive meniscus lens, a biconcave lens and a negative meniscus lens arranged sequentially along the optical path;

[0013] The laser beam expander branch is an off-axis total internal reflection focalless system, which includes a convex reflector and a concave reflector arranged sequentially along the optical path.

[0014] As a further improvement: both the primary mirror and the secondary mirror are aspherical mirrors; among them, the conic coefficient c of the primary mirror satisfies: -2 < c < -0.8;

[0015] The conic coefficient c of the secondary mirror satisfies: -4.8 < c < -2.

[0016] As a further improvement: the working spectral range of the imaging branch is 0.475μm to 0.690μm, the system focal length f satisfies: 2000mm < f < 2500mm, and the optical aperture is 380mm;

[0017] The working spectral range of the laser beam expander branch is 0.475μm to 2.300μm, the beam expansion magnification ratio is 5.95 times, the input aperture is 16.8mm, and the output aperture is 100mm.

[0018] As a further improvement: the laser beam expander branch is arranged off-axis with respect to the optical axis of the preposed common-aperture main optical system, and the off-axis amount is 118mm.

[0019] As a further improvement: the radius of curvature R11 of the convex mirror satisfies: 290mm < R11 < 308mm; the radius of curvature R12 of the concave mirror satisfies: 495mm < R12 < 544mm.

[0020] As a further improvement: the material of the first positive meniscus lens is fused silica, the material of the second positive meniscus lens is H-ZF3 glass, the material of the bi-concave lens is H-LAK53A glass, and the material of the negative meniscus lens is H-ZLAF55D glass.

[0021] Compared with the prior art, the beneficial effects of the present invention are as follows: the integrated architecture of common-aperture and split field-of-view is adopted to realize the common optical path design of the focused system and the afocal system, integrate the focusing imaging and afocal beam expansion optical paths with different focal lengths and different field-of-view requirements under the same optical aperture, realize the collaborative working ability of high-resolution imaging and high-magnification supercontinuum laser beam expansion, effectively reduce the number of large mirror groups and structural redundancy of the optical system, and has the characteristics of small volume and high structural integration. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the overall concept of an integrated optical system for split field-of-view common-aperture imaging and laser beam expansion;

[0023] Figure 2 It is a coaxial catadioptric and TMA fusion design diagram of an integrated optical system for split field-of-view common-aperture imaging and laser beam expansion;

[0024] Figure 3This is a schematic diagram of the overall structure of an integrated optical system for field-of-view common-aperture imaging and laser beam expansion.

[0025] Figure 4 Optical path diagram for the design of a coaxial folding and off-axis four-reflector fusion optical system for a field-of-view common aperture imaging and laser beam expansion integrated optical system;

[0026] Figure 5 This is a high-resolution imaging branch diagram of an integrated optical system combining field-of-view common-aperture imaging and laser beam expansion.

[0027] Figure 6 The MTF plot of a high-resolution imaging optical path of a field-of-view common-aperture imaging and laser beam expander integrated optical system at 156 lp / mm.

[0028] Figure 7 This is a high-resolution imaging branch point diagram of an integrated optical system combining field-of-view common-aperture imaging and laser beam expansion.

[0029] Figure 8 This is a laser beam expansion branch design diagram for an integrated optical system combining field-of-view common-aperture imaging and laser beam expansion.

[0030] Figure 9 This is a phase difference diagram of the laser beam expander's central field of view in an integrated optical system combining field-of-view common-aperture imaging and laser beam expander.

[0031] Figure 10 This is a phase difference diagram of the laser beam expander edge field of view of an integrated optical system for split field-of-view common aperture imaging and laser beam expander.

[0032] In the diagram: 1. Aperture; 2. Convex aspherical secondary mirror; 3. Concave aspherical primary mirror; 4. Imaging lens group; 40. Plane mirror; 41. First positive meniscus lens; 42. Second positive meniscus lens; 43. Biconcave lens; 44. Negative meniscus lens; 5. Laser beam expander lens group; 51. Convex mirror; 52. Concave mirror. Detailed Implementation

[0033] The technical solution of this application will be further described in detail below with reference to specific embodiments.

[0034] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0035] Please see Figures 1 to 3 In one embodiment, an integrated optical system for field-of-view co-aperture imaging and laser beam expansion includes:

[0036] A front-mounted common-aperture primary optical system, the front-mounted common-aperture primary optical system comprising a primary mirror and a secondary mirror;

[0037] An imaging branch is set at the image side of the front common-aperture main optical system for receiving light signals from the target scene and performing focused imaging.

[0038] A laser beam expander branch is located at the image side of the front common aperture main optical system for expanding and emitting the input laser beam;

[0039] The front common aperture main optical system divides the optical field of view, with the optical path of the main field of view being guided to the imaging branch and the optical path of the off-field field of view being guided to the laser beam expander branch.

[0040] In this embodiment, since the system needs to achieve both focused and afocal imaging optical paths, traditional coaxial or off-axis reflection architectures can only meet the optical power modulation capability of a single system. Therefore, the system adopts an integrated design scheme combining a coaxial catadioptric system and an off-axis total reflection system. The design result is as follows: Figure 2 As shown.

[0041] It adopts an integrated architecture with common aperture and field of view to realize the common optical path design of the focused system and the unfocused system. Under the same optical aperture, it integrates focusing imaging and unfocused beam expansion optical paths with different focal lengths and different field of view requirements, realizing the synergistic working capability of high-resolution imaging and high-magnification supercontinuum laser beam expansion. It effectively reduces the number of large lens groups and structural redundancy in the optical system, and has the characteristics of small size and high structural integration.

[0042] like Figures 4 to 10 In another preferred embodiment shown, the imaging branch is a coaxial catadioptric focal system, including a plane mirror, a first positive meniscus lens, a second positive meniscus lens, a biconcave lens and a negative meniscus lens arranged sequentially along the optical path;

[0043] The laser beam expander branch is an off-axis total internal reflection focalless system, which includes a convex reflector and a concave reflector arranged sequentially along the optical path.

[0044] In this embodiment, the primary reflector is a concave aspherical reflector, and the secondary reflector is a convex aspherical reflector.

[0045] The system working principle diagram of the present invention is as follows: Figure 1As shown, the system consists of two configurations. One configuration is a high-resolution imaging branch, which includes a front-end common-aperture main optical system and a rear-end correction system. The rear-end correction system adopts a refractive structure and is composed of multiple spherical lenses. The lens materials used include SILICA, H-ZF3, H-LAK53A, H-ZLAF55D, etc.; the other configuration is a laser beam expansion and output branch, which includes a front-end common-aperture main optical system and a rear-end supercontinuum laser beam expansion system. The rear-end beam expansion system is composed of a convex mirror and a concave mirror; the front-end common-aperture main optical system is a common lens group for both configurations. The common-aperture main optical system adopts the Cassegrain form and is composed of a primary mirror and a secondary mirror, both of which adopt high-precision aspherical designs. The conic coefficient of the primary mirror is -2 < c < -0.8, and the conic coefficient of the secondary mirror is -4.8 < c < -2, which can effectively eliminate spherical aberration and coma. The concave aspherical mirror primary is a concave mirror, and the convex aspherical mirror secondary is a convex mirror; by dividing the field of view of the front-end optical system, the optical branch design for different application scenarios is realized.

[0046] In another preferred embodiment, the working spectral range of the imaging branch is 0.475μm to 0.690μm, the system focal length f satisfies: 2000mm < f < 2500mm, and the optical aperture is 380mm;

[0047] The working spectral range of the laser beam expansion branch is 0.475μm to 2.300μm, the beam expansion magnification ratio is 5.95 times, the input aperture is 16.8mm, and the output aperture is 100mm.

[0048] The laser beam expansion branch is off-axis with respect to the optical axis of the front-end common-aperture main optical system, and the off-axis amount is 118mm.

[0049] In this embodiment, the specific optical path operation mode is as follows: the optical system adopts a coaxial catadioptric optical system for full-aperture imaging. Since the front-mounted Cassegrain type bears the main optical power of the system, an intermediate image plane can be formed in the non-imaging field of view. Laser beam expansion of the off-field is achieved by connecting a relay optical path. Among them, the concave aspherical mirror primary mirror of the front common aperture main optical system collects the reflected light signal from the target scene through its full aperture. After reflection by the convex aspherical mirror secondary mirror of the front main optical system and transmission by the rear imaging correction mirror, focused imaging is achieved. The high-resolution imaging system can achieve an image quality with full-field wavefront aberration better than 1 / 10λ, a field of view of φ0.7°, a system focal length of 2299.97mm, a total lens length of 490mm, and a spectral range of 0.475um-0.690um. The optical aperture can reach 380mm, and a ground pixel resolution of 0.7m can be achieved at a 500km orbit. Simultaneously, the sub-apertures of the front common-aperture primary optics system are used for laser beam expansion. Utilizing the off-axis design of the sub-apertures of the concave aspherical primary mirror and the convex aspherical secondary mirror of the front common-aperture primary optics system, an off-axis four-mirror focusless beam expansion system architecture is achieved. The supercontinuum laser beam expansion system employs an off-axis aperture with an off-axis amount of 118 mm. The input aperture of the supercontinuum laser beam expansion system is 16.8 mm, the output aperture is 100 mm, the beam expansion ratio is 5.95 times, the total lens length is 697 mm, the spectral range is 0.475 μm-2.300 μm, the field of view is 0.2° × 0.2°, and the off-axis angle is 0.9°. The output beam is deflected and emitted from the system's exit end. Through precise off-axis design and aspherical application, high-quality laser output with a wavefront accuracy better than 1 / 10λ and a divergence angle of approximately less than 20 μrad is achieved.

[0050] The high-resolution imaging optical path is focused on the detector, and the specific parameters of the selected detector are: 9344×7000 pixels and 3.2μm pixel size.

[0051] like Figure 7 As shown, within the operating wavelength range of 0.475μm–0.690μm, the modulation transfer function (MTF) of the high-resolution imaging optical path remains above 0.30 at the Nyquist frequency of approximately 156 lp / mm for a detector pixel size of 3.2μm. This indicates that the high-resolution imaging branch of this invention still possesses ideal imaging contrast at the cutoff frequency. These results demonstrate that the system aberrations are adequately controlled, and edge details, texture information, and contour features are clearly transmitted. This significantly improves the accuracy of space-based target recognition, contour fitting, and centroid extraction, meeting the requirements for high-precision attitude measurement and high-resolution imaging.

[0052] In another preferred embodiment, the radius of curvature R11 of the convex mirror satisfies: 290 mm < R11 < 308 mm; the radius of curvature R12 of the concave mirror satisfies: 495 mm < R12 < 544 mm.

[0053] In this embodiment, a diaphragm 1, a convex aspherical mirror secondary mirror 2, a concave aspherical mirror primary mirror 3, an imaging lens group 4, and a laser beam expander lens group 5 are sequentially arranged along the light incident direction. The imaging lens group 4 is composed of a plane mirror 40, a first positive meniscus lens 41, a second positive meniscus lens 42, a biconcave lens 43, and a negative meniscus lens 44. The laser beam expander lens group 5 is composed of a convex mirror 51 and a concave mirror 52.

[0054] The air gap between the diaphragm 1 and the concave aspherical mirror primary mirror 3 is 30 mm, the air gap between the concave aspherical mirror primary mirror 3 and the convex aspherical mirror secondary mirror 2 is 320 mm, the air gap between the convex aspherical mirror secondary mirror 2 and the plane mirror 40 is 490 mm, the air gap between the plane mirror 40 and the first positive meniscus lens 41 is 36 mm, the air gap between the first positive meniscus lens 41 and the second positive meniscus lens 42 is 24.757 mm, the air gap between the second positive meniscus lens 42 and the biconcave lens 43 is 5.113 mm, the air gap between the biconcave lens 43 and the negative meniscus lens 44 is 9.562 mm, the air gap between the diaphragm and the convex mirror 51 is 490 mm, and the air gap between the convex mirror 51 and the concave mirror 52 is 70.319 mm.

[0055] The optical characteristics of the first positive meniscus lens 41 are:

[0056] 0.05f < f1 < 0.1f, 1.4 < n1 < 1.5, -0.4f1 < R1 < -0.2f1, -0.2f1 < R2 < -0.1f1, D1 = -6.000, D2 = -15.644;

[0057] The optical characteristics of the second positive meniscus lens 42 are:

[0058] 0.1f < f2 < 0.2f, 1.7 < n2 < 1.8, 0.3f2 < R3 < 0.5f2, 0.2f2 < R4 < 0.3f2, D3 = -4.000, D4 = -1.913;

[0059] The optical characteristics of the biconcave lens 43 are:

[0060] 0.01f < f3 < 0.03f, 1.7 < n3 < 1.8, 1.5f3 < R5 < 1.7f3, -1.5f3 < R6 < -1.3f3, D5 = -3.200, D6 = -3.411;

[0061] The optical characteristics of the negative meniscus lens 44 are as follows:

[0062] 0.3f<f4<0.6f′, 1.8<n4<1.9, 0.03f4<R7<0.05f4, 0.03f4<R8<0.05f4, D7=-6.151, D8=-18.000;

[0063] The optical characteristics of the primary mirror 3 of the concave aspherical reflecting mirror are as follows:

[0064] 0.1f<f5<0.2f, 1.8f5<R9<2.1f5, D9=-320.000, -2 <c<-0.8;

[0065] The optical characteristics of the secondary mirror 2 of the convex aspherical reflecting mirror are as follows:

[0066] -0.1f<f6<-0.01f, 1.7f6<R10<2.3f6, D10=320.000, -4.8 <c<-2;

[0067] The optical characteristics of the convex reflector 51 are as follows:

[0068] f<<f7, 290<R11<308, D11=-215.000;

[0069] The optical characteristics of the concave mirror 52 are as follows:

[0070] f<<f7, 495<R12<544, D12=235.000;

[0071] Where f is the focal length of the entire high-resolution imaging optical system, f1, f2, f3, and f4 are the focal lengths of the first positive meniscus lens 41, the second positive meniscus lens 42, the biconcave lens 43, and the negative meniscus lens 44, respectively; f5, f6, f7, and f8 are the focal lengths of the concave aspherical mirror primary mirror 3, the convex aspherical mirror secondary mirror 2, the convex mirror 51, and the concave mirror 52, respectively; R1, R2, R3...R8 are the radii of curvature of the eight surfaces of the four lenses, respectively; and R9, R10, R11, and R12 are the focal lengths of the concave aspherical mirror primary mirror 3, the convex aspherical mirror secondary mirror 2, the convex mirror 51, and the concave mirror 52, respectively. The radii of curvature of the aspherical secondary mirror 2, the convex mirror 51, and the concave mirror 52 are given. n1, n2, n3, and n4 are the refractive indices of the four lenses, respectively. D1, D2...D8 are the thicknesses of the eight surfaces of the four lenses, respectively. D9, D10, D11, and D12 are the thicknesses of the concave aspherical primary mirror 3, the convex aspherical secondary mirror 2, the convex mirror 51, and the concave mirror 52, respectively. In this system, the concave aspherical primary mirror 3, the convex aspherical secondary mirror 2, the convex mirror 51, and the concave mirror 52 are all aspherical mirrors.

[0072] In another preferred embodiment, the first positive meniscus lens is made of fused silica, the second positive meniscus lens is made of H-ZF3 glass, the biconcave lens is made of H-LAK53A glass, and the negative meniscus lens is made of H-ZLAF55D glass.

[0073] In this embodiment, the first positive meniscus lens 41 is made of SILICA glass, the second positive meniscus lens 42 is made of H-ZF3 glass, the biconcave lens 43 is made of H-LAK53A glass, and the negative meniscus lens 44 is made of H-ZLAF55D glass.

[0074] Optical systems with higher spatial resolution generally have larger apertures. Aperture and weight increase exponentially, so a larger aperture means a greater weight. This invention integrates the functions of optical imaging and laser beam expansion systems within the same main optical system through a common-aperture, multi-field-of-view integrated design. This design significantly reduces the weight and volume of the system and avoids the redundancy problem caused by the superposition of two optical systems in traditional dual-optical-path systems. It has important strategic significance for platforms with high requirements for lightweighting, such as aerospace micro-nano platforms and small UAVs.

[0075] The biggest development cost of a reflection system lies in the production, manufacturing, and assembly of the primary and secondary reflectors. Since this invention adopts a dual-system common mirror design method, it reduces the number of large primary reflector components and adds four small transmission elements, which will significantly reduce system costs and improve the engineering transformation capability of this invention patent.

[0076] This patent adopts a field-of-view beam splitting design logic. Although it uses a common aperture main optical path design, the branch design is relatively independent and the spectral coverage is independent. It can realize the spectral overlap design of different functional branches, which is conducive to the application development of multi-mode scenarios for different spectral targets.

[0077] This invention integrates two independent optical paths into a single system through an innovative design, avoiding the problems of redundant optical paths and bulky size in traditional split systems. This system not only improves integration but also effectively reduces the difficulty of optical axis alignment and assembly, thereby enhancing system reliability.

[0078] This invention employs an integrated design combining a coaxial catadioptric system and an off-axis total reflection system. By utilizing two optical branches with different optical powers and fields of view within the same common aperture system, it achieves an integrated design of high-resolution imaging and high-magnification laser beam expansion. The optical field of view is segmented using a front-mounted common-aperture main optical system, and the different aperture optical paths of the primary and secondary mirrors guide the light to the optical imaging branch and the laser beam expansion branch respectively, thus achieving dual-function integration without significantly increasing size and weight. The optical imaging branch is primarily responsible for high-resolution target perception of the target area, while the laser beam expansion branch is responsible for high-magnification expansion and output of the supercontinuum laser beam, serving space laser communication or long-distance energy transmission.

[0079] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention, and no reference numerals in the claims should be construed as limiting the scope of the claims.

[0080] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A split field-of-view co-boresight imaging and laser beam expander integrated optical system, characterized in that, The application relates to a front-mounted common-aperture main optical system, an imaging branch and a laser beam expanding branch. The front-mounted common-aperture main optical system comprises a main mirror and a secondary mirror. The imaging branch is arranged on an image side of the front-mounted common-aperture main optical system and is used for receiving light signals from a target scene and focusing imaging. The laser beam expanding branch is arranged on the image side of the front-mounted common-aperture main optical system and is used for expanding and emitting input laser beams. The front-mounted common-aperture main optical system divides an optical field of view, and the light path of a main field of view is guided to the imaging branch, and the light path of an off-axis field of view is guided to the laser beam expanding branch. The imaging branch is a coaxial catadioptric focusing system and comprises, in sequence along a light path, a plane mirror, a first positive meniscus lens, a second positive meniscus lens, a double-concave lens and a negative meniscus lens. The laser beam expanding branch is an off-axis all-reflection afocal system and comprises, in sequence along a light path, a convex mirror and a concave mirror. The working spectral range of the imaging branch is 0.475-0.690 mu m, the system focal length f satisfies 2000 mm < f < 2500 mm, and the optical aperture is 380 mm. The working spectral range of the laser beam expanding branch is 0.475-2.300 mu m, the beam expanding and magnification ratio is 5.95 times, the input aperture is 16.8 mm, and the output aperture is 100 mm. The laser beam expanding branch is arranged off-axis relative to the optical axis of the front-mounted common-aperture main optical system. 2.The split-aperture imaging and laser beam expander integrated optical system of claim 1, wherein, The main mirror and the secondary mirror are both aspheric mirrors, wherein the conic coefficient c of the main mirror satisfies -2 < c < -0.

8. The conic coefficient c of the secondary mirror satisfies -4.8 < c < -2. 3.The split-aperture imaging and laser beam expander integrated optical system of claim 1, wherein, The off-axis amount is 118 mm.

4. The split-aperture imaging and laser beam expander integrated optical system of claim 1, wherein, The curvature radius R11 of the convex mirror satisfies 290 mm < R11 < 308 mm, and the curvature radius R12 of the concave mirror satisfies 495 mm < R12 < 544 mm.

5. The split-aperture imaging and laser beam expander integrated optical system of claim 1, wherein, The material of the first positive meniscus lens is fused quartz, the material of the second positive meniscus lens is H-ZF3 glass, the material of the double-concave lens is H-LAK53A glass, and the material of the negative meniscus lens is H-ZLAF55D glass.

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