Off-axis compound optical system with automatic aberration compensation

Abstract

This invention discloses an off-axis composite optical system with automatic aberration compensation, belonging to the field of optical design. It includes a radome, an infrared lens, an infrared detector, a correction lens, a television lens, and a television detector. The radome, infrared lens, and infrared detector form an infrared optical system, while the radome, correction lens, television lens, and television detector form a television optical system. The infrared and television optical systems share a radome. Parallel light from infinity enters the infrared lens from the object plane through the radome, balancing thermal difference, chromatic aberration, and monochromatic aberration, and finally images onto the focal plane of the infrared detector. Parallel light from infinity enters the correction and television lenses from the object plane through the radome, balancing thermal difference, chromatic aberration, and monochromatic aberration, and finally images onto the focal plane of the television detector. This invention integrates the visible light path and the long-wavelength infrared light path, enabling simultaneous detection and identification of targets across two bands, facilitating earlier target detection and identification.

Description

Technical Field

[0001] This invention belongs to the field of optical design, specifically relating to an off-axis composite optical system with automatic aberration compensation. Background Technology

[0002] Dual-band optical systems can detect objects in two bands, detecting targets at different wavelengths. This is something a single optical system cannot do. It combines the advantages of visible light and infrared optical systems.

[0003] Modern optoelectronic detection systems typically include infrared thermal imagers and television cameras, and have wide applications in military strikes, fire control, optoelectronic detection, and reconnaissance and early warning. Existing solutions employ a coaxial design for combined infrared and television imaging systems.

[0004] Currently, commonly used composite coaxial systems combining infrared imaging and television imaging have the following shortcomings:

[0005] 1) The central aperture of the infrared optical system will be blocked by the television optical system, resulting in a significant loss of light flux, a decrease in the diffraction limit, and a decrease in the transfer function performance at intermediate frequencies.

[0006] 2) The aperture of the infrared optical system cannot be too small, otherwise the central aperture will be blocked, resulting in a serious decline in the performance of the infrared system or even its inability to be used. However, due to the large frame angle requirements or the small diameter of the seeker head, the aperture of the infrared optical system in real products cannot be made too large.

[0007] 3) Since the television optical system is inside the infrared optical system channel, the size, configuration, performance, and assembly of the infrared and television optical systems will affect each other, increasing the difficulty of design, assembly, and subsequent maintenance.

[0008] 4) If the TV detector is placed inside the infrared channel and directly behind the TV lens, the size of the TV detector must be very small, otherwise it will block too much light from the infrared optical system. If the TV detector is reflected to the outside of the infrared optical system by means of a reflector, the design of the intercept after lengthening the TV optical system with a short focal length will be very difficult. Summary of the Invention

[0009] The technical problem to be solved:

[0010] To overcome the shortcomings of existing technologies, this invention provides an off-axis composite optical system with automatic aberration compensation for simultaneous imaging in both television and infrared bands in a photoelectric detection system. This off-axis composite optical system with automatic aberration compensation uses a single spherical radome for both the infrared and television optical systems, fusing the visible light path and the long-wave infrared light path to achieve simultaneous target detection and identification across the two bands. This facilitates earlier target detection and identification, and the combination of visible and infrared bands enables more accurate and detailed target information.

[0011] The technical solution of the present invention is: an off-axis composite optical system with automatic aberration compensation, comprising a radome, an infrared lens, an infrared detector, a correction lens, a television lens, and a television detector. The radome, infrared lens, and infrared detector form an infrared optical system, and the radome, correction lens, television lens, and television detector form a television optical system; the infrared optical system and the television optical system share the same radome.

[0012] Parallel light from infinity enters the infrared lens through the radome from the object surface, balancing the thermal difference, chromatic aberration, and monochromatic aberration of the system, and finally images onto the focal plane of the infrared detector, completing the entire process of infrared optical path imaging; parallel light from infinity enters the correction lens and television lens through the radome from the object surface, balancing the thermal difference, chromatic aberration, and monochromatic aberration of the system, and finally images onto the focal plane of the television detector, completing the entire process of visible light path imaging.

[0013] A further technical solution of the present invention is: the infrared optical system is a coaxial optical system, the television optical system is an off-axis optical system, and the Y-direction is eccentric by 36mm.

[0014] A further technical solution of the present invention is: the correction lens is composed of two tilted and rotationally symmetrical visible light lenses, which are installed together with the television lens in the television barrel to complete the system's azimuth and elevation angle scanning imaging.

[0015] A further technical solution of the present invention is as follows: the first corrective lens of the corrective lens is a positive lens, with the convex surface facing the object surface, the front surface being spherical with a radius of curvature of 90.400 mm, the rear surface being flat, the material being HZK9A_CDGM, the Y-direction eccentricity being 36 mm, and the α tilt angle being 32.2 degrees; the second corrective lens is a negative lens, with the concave surface facing the object surface, the front surface being flat, the rear surface being spherical with a radius of curvature of 85.167 mm, the material being HLAF2_CDGM, the Y-direction eccentricity being 36 mm, and the α tilt angle being 32.2 degrees.

[0016] A further technical solution of the present invention is: the television lens has six lenses arranged sequentially along the optical path, and all surfaces are spherical.

[0017] A further technical solution of the present invention is: the specific parameters of the six lenses of the television lens are as follows:

[0018] The first television lens has a front surface radius of curvature of 30.253 mm, a rear surface radius of curvature of 366.993 mm, a thickness of 2 mm, and an effective aperture of 8 mm. The material is HZPK2A_CDGM. The second television lens has a front surface radius of curvature of 17.618 mm, a rear surface radius of curvature of 103.474 mm, a thickness of 2 mm, and an effective aperture of 7.2 mm. The material is HQK3L_CDGM. The third television lens is a cemented lens with a front surface radius of curvature of -63.132 mm, a middle surface radius of curvature of 26.306 mm, and a rear surface radius of curvature of -41.388 mm. The front lens is 2 mm thick, the rear lens is 6 mm thick, and the effective aperture is 5.6 mm. The material is... The fourth television lens has a front surface curvature radius of 26.112 mm, a rear surface curvature radius of 47.721 mm, a thickness of 2.3 mm, an effective aperture of 6.4 mm, and is made of HLAF54_CDGM. The fifth television lens has a front surface curvature radius of 7.605 mm, a rear surface curvature radius of 5.355 mm, a thickness of 2 mm, an effective aperture of 6 mm, and is made of HLAF10LA_CDGM. The sixth television lens has a front surface curvature radius of 35.734 mm, a rear surface curvature radius of 28.931 mm, a thickness of 4.2 mm, an effective aperture of 5.5 mm, and is made of HZF13_CDGM.

[0019] A further technical solution of the present invention is as follows: the infrared lens is provided with three lenses in sequence along the optical path. The first infrared lens has a spherical front surface with a radius of curvature of 74 mm and an aspherical rear surface with a radius of curvature of 127.652 mm. Its thickness is 13 mm, and its effective aperture is 91 mm. The material is domestic chalcogenide glass IRG206. The second infrared lens has a spherical front surface with a radius of curvature of 38.042 mm and an aspherical rear surface with a radius of curvature of 29.123 mm. Its thickness is 4 mm, and its effective aperture is 46 mm. The material is germanium. The third infrared lens has an aspherical front surface with a radius of curvature of 47.125 mm and a spherical rear surface with a radius of curvature of 60.942 mm. Its thickness is 4.5 mm, and its effective aperture is 40 mm. The material is germanium.

[0020] A further technical solution of the present invention is: the first infrared lens, the second infrared lens, and the third infrared lens are respectively a first meniscus positive lens, a meniscus negative lens, and a second meniscus positive lens, and their convex surfaces all face the object surface.

[0021] A further technical solution of the present invention is: the fairing is a concentric spherical fairing with equal thickness that is used for both long-wave infrared and television dual-band light transmission, and can transmit both long-wave infrared light and visible light at the same time; the front surface of the fairing has a radius of curvature of 80 mm and a thickness of 4 mm, the rear surface has a radius of curvature of 76 mm, and the material is multispectral zinc sulfide.

[0022] A further technical solution of the present invention is: the total length of the infrared optical system is <123mm, the F number is 1.1, and the field of view is 11°; the total length of the television optical system is <86mm, the F number is 4.5, and the field of view is 10.4°.

[0023] Beneficial effects

[0024] The beneficial effects of this invention are as follows: Traditional coaxial infrared television composite systems place the television optical system in the middle of the infrared optical system through an opening. This means that the total length of the television optical system cannot be too long, otherwise it will also lead to the infrared optical system being too long and unable to meet the requirements of the large frame angle of the seeker head. At the same time, because the light rays are more contracted as the optical system gets closer to the image plane, the total length of the television optical system should be as short as possible to reduce the light blocking of the infrared optical system. Furthermore, when the central aperture of the infrared optical system is blocked, the optical transfer function of the system will decrease at the mid-frequency and diffraction limits, and the decrease will be more severe as the blocking area increases. In this design, the television optical system is placed off-axis at the edge of the infrared optical system, avoiding the drop in intermediate frequency of the transfer function caused by the central aperture. Simultaneously, the overall length of the television optical system can be appropriately increased, while the lens layout of the infrared optical system remains unaffected. Comparing coaxial and off-axis infrared television composite optical systems with the same optical specifications, frame angles, and structural space, the off-axis system can achieve twice the overall length of the coaxial system without interference. Furthermore, the off-axis infrared optical system has an intermediate frequency of transfer function and a diffraction limit that are more than 0.1 higher than the coaxial system, resulting in more relaxed tolerances for both the infrared and television optical systems compared to the coaxial system. Therefore, the off-axis infrared television composite optical system has the following advantages over the coaxial infrared television composite optical system:

[0025] (1) The central aperture of the infrared optical system will not be blocked by the television optical system, resulting in less light flux loss and no decrease in diffraction limit and mid-frequency transfer function performance.

[0026] (2) The aperture of the infrared optical system does not need to be made very large under the condition that the frame angle and the effective distance requirements are met, thus reducing the design difficulty.

[0027] (3) The television optical system and the infrared optical system are two channels that do not affect each other. Their size, configuration, performance and installation will not affect each other, which reduces the difficulty of design, assembly and later maintenance, and improves economy, operability and practicality.

[0028] (4) Television detectors can be selected as needed, without having to choose those that are very small, which increases the selectivity of detectors and also reduces the design difficulty of the intercept after the optical path is lengthened by turning.

[0029] This invention provides an optical system for achieving infrared and television multispectral imaging and target detection in a multispectral photoelectric detection system. The coaxial infrared optical system is a three-element passively adiabatic long-wave infrared optical system based on a hybrid infrared refraction / diffraction lens. The off-axis television optical system uses a corrective lens to automatically correct aberrations and aiming errors. After aberration and aiming error correction, optical aberrations and aiming errors introduced by the tilt of the spherical radome relative to the subsequent off-axis television optical system are eliminated. This optical system solves the problems in coaxial optical systems where the central aperture of the infrared optical system is blocked by the television optical system, resulting in a decrease in the intermediate frequency transfer function and limited design space. While achieving infrared and visible light detection, it also possesses automatic aberration and aiming error correction functions, effectively solving the optical aberration and aiming error problems existing in off-axis television optical systems under a spherical radome. This optical system features multi-spectral bands, small size, lightweight design, and high imaging quality, meeting the photoelectric detection requirements of large frame angles. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the composite seeker positioner.

[0031] Figure 2 It is an infrared light path tracing diagram.

[0032] Figure 3 It is a television optical path tracing diagram.

[0033] Explanation of reference numerals in the attached drawings: 1. Fairing; 2. Infrared lens; 3. Infrared detector; 4. Correction lens; 5. Television lens; 6. Television detector; 7. Optical path receiving station; 21. First infrared lens; 22. Second infrared lens; 23. Third infrared lens; 41. First correction lens; 42. Second correction lens; 51. First television lens; 52. Second television lens; 53. Third television lens; 54. Fourth television lens; 55. Fifth television lens; 56. Sixth television lens. Detailed Implementation

[0034] The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the invention, and should not be construed as limiting the invention.

[0035] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0036] When the photoelectric detection system is in scanning detection mode, the optical system completes the optical detection of the target. The off-axis composite optical system in this invention mainly consists of a radome 1, an infrared lens 2, an infrared detector 3, a correction lens 4, a television optical lens 5, and a television detector 6. This optical system is a composite optical system composed of an infrared optical system and a television optical system. The infrared optical system is composed of the radome 1, infrared lens 2, and infrared detector 3, while the television optical system is composed of the radome 1, correction lens 4, television lens 5, and television detector 6. The infrared optical system and the television optical system share the radome 1. The spherical radome 1 serves as the optical window for receiving light from outside the system. After passing through the spherical radome, the light reaches the infrared lens 2, correction lens 4, and television lens 5. The infrared lens 2 only transmits infrared light, while the television lens 5 only transmits visible light. After passing through the infrared lens 2, the infrared light reaches the infrared detector 3, thus realizing the conversion of infrared light signals into electrical signals. Visible light rays first pass through the correction lens 4, which automatically corrects for light deflection and wavefront errors caused by the spherical rectifier 1. Then, after passing through the television lens 5, they reach the television detector 6, realizing the conversion of visible light signals into electrical signals. The television optical system supports aberration correction and aiming error correction under dynamic scanning.

[0037] In this embodiment, parallel light from infinity enters the infrared lens 2 through the rectifier 1 from the object surface, balancing the system's thermal difference, chromatic aberration, and monochromatic aberration, and finally images onto the focal plane of the infrared detector 3, completing the entire process of infrared optical path imaging. Similarly, parallel light from infinity enters the correction lens 4 and the television lens 5 through the rectifier 1 from the object surface, balancing the system's thermal difference, chromatic aberration, and monochromatic aberration, and finally images onto the focal plane of the television detector 6, completing the entire process of visible light path imaging. This technical solution employs an off-axis dual-channel refractive imaging structure to achieve the design of an infrared television composite optical system. It utilizes a passive, thermal optical design method to achieve infrared and visible light detection of targets within a wide temperature range of -55℃ to +70℃, with a frame angle that can achieve azimuth and elevation ±25°. The infrared optical system and the television optical system share the same rectifier 1. The infrared optical system is a coaxial optical system, while the television optical system is an off-axis optical system with a 36mm offset in the Y direction.

[0038] The infrared optical system and the television optical system in this optical system can be designed separately.

[0039] The infrared optical system adopts a passive, calorimetric design and includes a radome 1, an infrared lens 2, and an infrared detector 3. The operating wavelength is 8µm-14µm.

[0040] The fairing 1 is a concentric, equal-thickness dome that shares both long-wave infrared and television dual-band coverage, allowing simultaneous transmission of both long-wave infrared and visible light. While ensuring effective transmission of infrared and visible light, the fairing 1 is shaped to fit the application system, reducing its aerodynamic drag. Furthermore, to ensure the normal operation of the optoelectronic system within the application system, the fairing 1 isolates the optoelectronic system from the external environment and allows radiation from the operating band of the optoelectronic system to pass through. The front surface of the fairing 1 has a radius of curvature of 80 mm and a thickness of 4 mm, while the rear surface has a radius of curvature of 76 mm. The material is multispectral zinc sulfide; the average transmittance in the 8 μm-14 μm band is 0.90.

[0041] The infrared lens 2 comprises three lenses. The first infrared lens 21 has a spherical front surface with a radius of curvature of 74 mm and an aspherical rear surface with a radius of curvature of 127.652 mm. It has a thickness of 13 mm and an effective aperture of 91 mm. The material is domestically produced chalcogenide glass IRG206. The second infrared lens 22 has a spherical front surface with a radius of curvature of 38.042 mm and an aspherical rear surface with a radius of curvature of 29.123 mm. It has a thickness of 4 mm and an effective aperture of 46 mm. The material is germanium. The third infrared lens 23 has an aspherical front surface with a radius of curvature of 47.125 mm and a spherical rear surface with a radius of curvature of 60.942 mm. It has a thickness of 4.5 mm and an effective aperture of 40 mm. The material is germanium.

[0042] The lens barrel of the infrared optical system is made of 7075 aluminum alloy; the infrared detector is a long-wavelength 8-14µm, resolution 1280×1024, and pixel size 12µm uncooled focal plane detector, which has the advantages of small size, light weight, and low power consumption. The first infrared lens 21 is a binary diffraction element with the diffraction surface located on the image plane side; the low refractive index coefficient and good dispersion performance of chalcogenide glass, as well as the negative dispersion coefficient and large temperature compensation characteristics of the binary optical diffraction element, are used to correct the chromatic aberration and thermal aberration of the infrared optical system; and coma and spherical aberration are corrected by introducing an aspherical coordinating system.

[0043] This infrared optical system employs two types of optical materials (excluding the radome) in a rationally allocated combination to mitigate thermal differences, resulting in a simple and compact structure with a small number of lenses (two). Within a temperature range of -55℃ to +70℃, the system exhibits a maximum defocus of less than one depth of focus, and at a spatial cutoff frequency of 42 lp / mm, the optical modulation transfer function (MTF) value is above 0.35 across the entire field of view, approaching the diffraction limit.

[0044] The infrared lens 2 in this design consists of a series of lenses with different thicknesses, radii of curvature, refractive indices, and dispersion coefficients to receive and converge long-wave infrared light onto the focal plane of the infrared detector. Because the refractive index of infrared materials varies greatly with temperature, a passive, athermal optical design is employed to achieve high-quality imaging across the entire operating temperature range of -55℃ to +70℃. The infrared lens uses three lenses to create a long-wave infrared light path, with a total transmittance of 0.85. See the infrared light path tracing diagram below. Figure 2 As shown.

[0045] The television optical system adopts a passive, calorimetric design and includes a radome 1, a correction lens 4, a television lens 5, and a television detector 6. The operating wavelength of the television optical system is 0.43µm-0.9µm. The radome 1 is a concentric, uniformly thick dome made of multispectral zinc sulfide, with an outer surface curvature radius of 80mm and a thickness of 4mm, and an inner surface curvature radius of 76mm. The average transmittance in the 0.43µm-0.9µm wavelength range is 0.90.

[0046] The corrective lens 4 is composed of two visible light lenses made of commonly used materials and tilted and rotationally symmetrical. This corrective lens and the television lens are mounted together in the television lens barrel to complete the system's azimuth and elevation angle scanning imaging. The first corrective lens 41 is a positive lens with its convex surface facing the object surface. Its front surface is spherical with a radius of curvature of 90.400 mm, and its rear surface is flat. The material is HZK9A_CDGM, with an eccentricity of 36 mm in the Y direction and an α tilt angle of 32.2 degrees. The second corrective lens 42 is a negative lens with its concave surface facing the object surface. Its front surface is flat, and its rear surface is spherical with a radius of curvature of 85.167 mm. The material is HLAF2_CDGM, with an eccentricity of 36 mm in the Y direction and an α tilt angle of 32.2 degrees.

[0047] The television lens comprises six lenses, all of which are spherical. The first television lens 51 has a front surface radius of curvature of 30.253 mm, a rear surface radius of curvature of 366.993 mm, a thickness of 2 mm, and an effective aperture of 8 mm. It is made of HZPK2A_CDGM material. The second television lens 52 has a front surface radius of curvature of 17.618 mm, a rear surface radius of curvature of 103.474 mm, a thickness of 2 mm, and an effective aperture of 7.2 mm. It is made of HQK3L_CDGM material. The third television lens 53 is a cemented lens with a front surface radius of curvature of -63.132 mm, a middle surface radius of curvature of 26.306 mm, and a rear surface radius of curvature of -41.388 mm. The front lens is 2 mm thick, and the rear lens is 6 mm thick. Its effective aperture is... The first television lens has an aperture of 5.6 mm and is made of HLAF4GT_CDGM and HQK3L_CDGM materials. The second television lens has an effective aperture of 6.4 mm and is made of HLAF54_CDGM materials. The third television lens has an effective aperture of 6 mm and is made of HLAF10LA_CDGM materials. The fourth television lens has an effective aperture of 5.6 mm and is made of HLAF4GT_CDGM and HQK3L_CDGM materials. The fifth television lens has an effective aperture of 6 mm and is made of HLAF10LA_CDGM materials. The sixth television lens has an effective aperture of 5.5 mm and is made of HZF13_CDGM materials. The fifth television lens has an effective aperture of 6 mm and is made of HLAF10LA_CDGM materials. The sixth television lens has an effective aperture of 5.5 mm and is made of HLAF4GT_CDGM and HQK3L_CDGM materials.

[0048] The lens barrel of the television optical system is made of aluminum alloy. Aberrations are eliminated through reasonable allocation and combination, resulting in a simple and compact structure. Within a temperature range of -55℃ to +70℃, the system exhibits an optical transfer function (IPF) value above 0.3 across the entire field of view at a spatial cutoff frequency of 125 lp / mm, demonstrating good image quality. The television detector employs a CMOS image sensor with a detector response band of 0.43-0.9 μm, a resolution of 1280×1024, and a pixel size of 4 μm. It receives light from the television optical system, converts the light signal into a digital image signal through the photoelectric effect, and outputs it, offering advantages such as fast response and low power consumption. Since the fairing 1 is tilted in the YZ plane relative to the off-axis television optical system behind it, it introduces non-rotational symmetry aberrations and aiming errors. These non-rotational symmetry aberrations cannot be corrected by rotationally symmetric lenses because they will always form rotationally symmetric aberrations. However, tilting it will introduce non-rotational symmetry aberrations. By setting the tilt amount and radius of curvature as variables and constraining the position of the 0 field-of-view ray to reach the image plane to the center position, it is possible to cancel out the aberrations and aiming errors introduced by the fairing, thereby obtaining an optical system with good image quality.

[0049] In this embodiment, the television lens 5 operates at a wavelength of 0.43µm-0.9µm. The optical system comprises a series of lenses with varying thicknesses, radii of curvature, refractive indices, and dispersion coefficients to receive and converge visible light onto the focal plane of the television detector. A passive, calorimetric design enables high-quality imaging across the entire operating temperature range of -55℃ to +70℃. The television lens in this design utilizes commonly used optical glass to achieve the visible light path, and the total transmittance of the television optical system is 0.85. See the television optical path ray tracing diagram below. Figure 3 As shown.

[0050] During the scanning process of the photoelectric detection system, light rays pass through the spherical radome 1 and then reach the infrared lens 2, the correction lens 4, and the television lens 5. The infrared lens 2 only transmits infrared light, while the television lens 5 only transmits visible light. The infrared light rays, after passing through the infrared lens 2, reach the infrared detector 3, where the infrared light signal is converted into an electrical signal. The visible light rays first pass through the correction lens 2, which automatically corrects for the light deflection and wavefront errors caused by the spherical radome 1. Then, after passing through the television lens 5, they reach the television detector 6, where the visible light signal is converted into an electrical signal. This optical system enables both infrared imaging detection and television imaging detection of the target.

[0051] The design concept of the automatic correction function of this optical system is not limited to the television band, but is also applicable to the infrared band and laser band.

[0052] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention without departing from the principles and spirit of the present invention.

Claims

1. An off-axis compound optical system with automatic aberration compensation, characterized in that: It includes a radome, an infrared lens, an infrared detector, a correction lens, a television lens, and a television detector. The radome, infrared lens, and infrared detector form an infrared optical system, and the radome, correction lens, television lens, and television detector form a television optical system. The infrared optical system and the television optical system share the same radome. The television lens has six lenses arranged sequentially along the optical path, and all surfaces are spherical. The specific parameters of the six lenses in the television lens are as follows: The first television lens has a front surface radius of curvature of 30.253 mm, a rear surface radius of curvature of 366.993 mm, a thickness of 2 mm, an effective aperture of 8 mm, and is made of HZPK2A_CDGM material. The second television lens has a front surface radius of curvature of 17.618 mm, a rear surface radius of curvature of 103.474 mm, a thickness of 2 mm, an effective aperture of 7.2 mm, and is made of HQK3L_CDGM material. The third television lens is a cemented lens with a front surface radius of curvature of -63.132 mm, a middle surface radius of curvature of 26.306 mm, and a rear surface radius of curvature of -41.388 mm. The front lens is 2 mm thick, the rear lens is 6 mm thick, and its effective aperture is 5.6 mm. It is made of HLAF4GT_CDGM material. The fourth television lens has a front surface curvature radius of 26.112 mm, a rear surface curvature radius of 47.721 mm, a thickness of 2.3 mm, an effective aperture of 6.4 mm, and is made of HLAF54_CDGM. The fifth television lens has a front surface curvature radius of 7.605 mm, a rear surface curvature radius of 5.355 mm, a thickness of 2 mm, an effective aperture of 6 mm, and is made of HLAF10LA_CDGM. The sixth television lens has a front surface curvature radius of 35.734 mm, a rear surface curvature radius of 28.931 mm, a thickness of 4.2 mm, an effective aperture of 5.5 mm, and is made of HZF13_CDGM. The infrared lens comprises three lenses arranged sequentially along the optical path. The first infrared lens has a spherical front surface with a radius of curvature of 74 mm and an aspherical rear surface with a radius of curvature of 127.652 mm. It has a thickness of 13 mm and an effective aperture of 91 mm. The material is domestic chalcogenide glass IRG206. The second infrared lens has a spherical front surface with a radius of curvature of 38.042 mm and an aspherical rear surface with a radius of curvature of 29.123 mm. It has a thickness of 4 mm and an effective aperture of 46 mm. The material is germanium. The third infrared lens has an aspherical front surface with a radius of curvature of 47.125 mm and a spherical rear surface with a radius of curvature of 60.942 mm. It has a thickness of 4.5 mm and an effective aperture of 40 mm. The material is germanium. Parallel light from infinity enters the infrared lens through the radome from the object surface, balancing the thermal difference, chromatic aberration, and monochromatic aberration of the system, and finally images onto the focal plane of the infrared detector, completing the entire process of infrared optical path imaging; parallel light from infinity enters the correction lens and television lens through the radome from the object surface, balancing the thermal difference, chromatic aberration, and monochromatic aberration of the system, and finally images onto the focal plane of the television detector, completing the entire process of visible light path imaging.

2. The off-axis compound optical system with automatic aberration compensation according to claim 1, characterized in that: The infrared optical system is a coaxial optical system, while the television optical system is an off-axis optical system with a Y-axis offset of 36mm.

3. The off-axis compound optical system with automatic aberration compensation according to claim 1, characterized in that: The correction lens consists of two tilted, rotationally symmetrical visible light lenses, which are installed together with the television lens in the television barrel to complete the system's azimuth and elevation angle scanning imaging.

4. The off-axis compound optical system with automatic aberration compensation according to claim 3, characterized in that: The first corrective lens of the corrective lens is a positive lens with its convex surface facing the object plane. Its front surface is spherical with a radius of curvature of 90.400 mm, and its rear surface is flat. The material is HZK9A_CDGM, and it has an eccentricity of 36 mm in the Y direction. The tilt angle is 32.2 degrees; the second corrective lens is a negative lens, with its concave surface facing the object plane, a flat front surface, a spherical rear surface, a radius of curvature of 85.167 mm, and is made of HLAF2_CDGM material. The Y-direction eccentricity is 36 mm. The tilt angle is 32.2 degrees.

5. The off-axis compound optical system with automatic aberration compensation according to claim 1, characterized in that: The first infrared lens, the second infrared lens, and the third infrared lens are respectively a first meniscus positive lens, a meniscus negative lens, and a second meniscus positive lens, and their convex surfaces all face the object surface.

6. The off-axis compound optical system with automatic aberration compensation according to claim 1, characterized in that: The fairing is a concentric, equal-thickness spherical fairing that shares both long-wave infrared and television dual-band light, and can transmit both long-wave infrared and visible light simultaneously. The front surface of the fairing has a radius of curvature of 80 mm and a thickness of 4 mm, while the rear surface has a radius of curvature of 76 mm. The material is multispectral zinc sulfide.

7. An off-axis compound optical system with automatic aberration compensation according to any one of claims 1-6, characterized in that: The infrared optical system has a total length of <123mm, an F-number of 1.1, and a field of view of 11°. The television optical system has a total length of <86mm, an F-number of 4.5, and a field of view of 10.4°.

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