All-day space optical sensor optical system
Through the all-day space optical sensor optical system, the shared optical path correction mirror group is used to realize parallel work between solar sensors and star sensors, solving the spectral compatibility and aberration optimization problems of the spacecraft attitude measurement system, and achieving high-precision and low-power attitude measurement and fast response.
Patent Information
- Application Number
- CN202510460930.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-14
- Publication Date
- 2025-07-11
AI Technical Summary
In the existing spacecraft attitude measurement systems, the optical systems of solar sensors and star sensors have poor spectral compatibility, weak anti-stitch light ability, poor structural compactness, high weight and power consumption, low light energy utilization, and difficult aberration optimization, and cannot achieve high-precision attitude measurement throughout the day.
The full-day space optical sensor optical system is adopted, and a compact optical lens is designed by using a common common optical path correction mirror group, combining a modular combination of refractive and reflective optical components, so as to realize parallel operation of solar sensors and star sensors, dynamically balance energy concentration and optical distortion, and optimize aberrations for common optical path design.
It realizes spacecraft attitude measurement with full-day, high-precision, and low-power consumption, solves the conjugate design of long and short focal length optical paths and the aberration optimization of different F-number optical systems, improves the reliability and accuracy of the system, and meets the spacecraft's rapid response needs.
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Figure CN120294960A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of optical imaging, and particularly relates to an optical system of an all-weather space optical sensor. Background Art
[0002] In the attitude measurement system of a spacecraft, accurate attitude measurement plays a crucial role in the normal operation and mission execution of the spacecraft. As the main space optical navigation devices in the attitude measurement system, sun sensors and star sensors shoulder key missions. Currently, in the field of spacecraft attitude measurement technology, there are significant differences in the optical radiation levels between sunlight and starlight, which makes it common for sun sensors and star sensors to use independent optical systems.
[0003] Sun sensors mainly rely on analyzing the solar incidence angle in the near-infrared spectrum (0.8 - 1.1 μm) to determine the orientation. They are the core components of spacecraft attitude control. To cope with the strong light environment in space, the core design requirements include high dynamic range (HDR) characteristics. Currently, there are two main technical routes: one is the quadrant photodetector (QPD) technology, which calculates the solar vector based on the spot displacement, but due to the constraints of the optical structure, the effective field of view is only ±30°; the other is digital imaging technology, which can achieve an accuracy of ±0.05° level using CMOS / APS sensors, but requires a multi-layer neutral density filter group to balance the light intensity. However, both of these technologies have obvious defects. On the one hand, the multi-spectral compatibility is poor, and the visible light transmittance of traditional optical systems is less than 50%, making it difficult to match the working band of star sensors; on the other hand, the anti-stray light ability is weak, and the secondary reflection of the mirror is likely to cause the detector to saturate, and the signal-to-noise ratio SNR < 10 dB in a typical strong light environment.
[0004] Star sensors achieve an attitude measurement accuracy of sub-arcsecond level (<1") through the recognition of star patterns in the visible light band (0.4 - 0.7 μm). Their technical implementation relies on a wide-field optical system, that is, a lens group with a field of view > 10°. Low-dispersion materials such as CaF2 are used to suppress chromatic aberration, and high-precision positioning algorithms are required. The optical distortion is required to be < 0.1% to ensure sub-pixel level star centroid positioning. However, it also faces problems. Firstly, there are limitations in spectral adaptation. The existing optical architectures cannot cover the near-infrared band and can only be deployed separately from sun sensors; secondly, the structural compactness is poor. A typical high-precision system requires 8 - 10 lens elements, and the overall mass > 500 g (such as the CT-633 type lens).
[0005] In the composite detection scheme, different schemes also have their own disadvantages. Taking the ESA Proba-V satellite as an example of the discrete architecture, the independent dual-system results in a mass > 1.5 kg, power consumption > 10 W, and also requires periodic optical axis correction (deviation > 0.5 mrad), greatly increasing the operation burden; for the beam splitter prism scheme, as shown in Patent CN201780012345.6, there is a problem of reduced light energy utilization rate, with the transmittance in the visible / near-infrared bands decreasing by 25% / 35% respectively, and the aberration superposition of the dual optical paths causing the star point positioning deviation to reach the 3-pixel level; for the dynamic filter scheme, based on the research of "Dual-mode star sensor design", the mechanical switching delay > 100 ms, which cannot meet the real-time control requirements, and the mechanical structure life < 5 years in the radiation environment.
[0006] Generally speaking, the existing technologies face many technical bottlenecks: in terms of focal length coverage, for the optical systems of traditional architectures, the distribution methods of the optical power of the optical elements in the long-focal-length and short-focal-length optical systems are mutually exclusive, and it is impossible to configure two focal lengths in one system; in terms of spectral compatibility, the transmittance curves of existing materials such as ordinary optical glass fluctuate violently in the 0.4 - 1.1 μm band. For example, the transmittance of H-K9L drops suddenly to 70% at 1.0 μm; it is difficult to synchronously optimize the chromatic aberration (axial chromatic aberration > 50 μm) and field curvature (> 0.1 mm) under wide spectra, and it is difficult to achieve aberration balance; when integrating the system, the beam splitting elements or mechanical switching mechanisms increase the complexity and reduce the reliability; the weight of the independent optical path > 2 kg, and the power consumption > 15 W.
[0007] In view of these problems existing in the attitude measurement of spacecraft in the prior art, the present invention proposes an all-weather space optical sensor optical system. Summary of the Invention
[0008] The purpose of the present invention is to provide an all-weather space optical sensor optical system, aiming to solve the problems raised in the above background technology.
[0009] The purpose of the present invention is achieved through the following technical solutions:
[0010] The all-weather space optical sensor optical system includes Configuration One and Configuration Two. Configuration One is the sun sensor mode, and Configuration Two is the star sensor mode. The two share a common optical path correction lens group; the sun sensor mode includes a sun sensor front lens group, which is composed of a convex mirror and a concave mirror. The convex mirror is a spherical mirror, and the concave mirror is an aspherical mirror; the star sensor mode includes a star sensor front lens group, which is composed of spherical lenses; the common optical path correction lens group is composed of spherical lenses.
[0011] The sunlight signal is collected by the front lens group of the sun sensor mode, with a clear aperture not larger than 2 mm and a collection range of a half field of view angle of 40° to 80°. The aberration of the system is corrected by the common path correction lens group to achieve clear imaging on the visible light detector, and the half length range of the imaging line field of view is 3.5 mm to 6.5 mm. The starlight signal is collected by the star sensor front lens group of the star sensor mode, with a clear aperture not less than 5 mm and a collection range of a half field of view angle of 0° to 7.5°. The aberration of the system is corrected by the common path correction lens group to achieve clear imaging on the visible light detector, and the half length range of the imaging line field of view is 0 mm to 2.5 mm.
[0012] Furthermore, the focal length of the sun sensor optical system is 4.75, the total lens length is 55.79 cm, the spectral range is 0.45 μm to 0.75 μm, the system aperture value is 2, and the half field of view is 40° to 80°.
[0013] Furthermore, the sun sensor optical system is sequentially provided with a first reflector, a second reflector, a front lens group, a first aperture stop, and a first rear lens group along the light incident direction. The front lens group is composed of a first positive meniscus lens, a negative meniscus lens, a double concave lens, and a double convex lens. The first rear lens group is composed of a second double convex lens, a third double convex lens, and a second double concave lens;
[0014] The air gap between the front lens group and the first aperture stop is 0.083 mm, and the air gap between the first aperture stop and the first rear lens group is 1.693 mm; the air gap between the first positive meniscus lens and the negative meniscus lens is 1.341 mm, the air gap between the negative meniscus lens and the double concave lens is 0.405 mm, and the air gap between the double concave lens and the double convex lens is 0.324 mm; the air gap between the second double convex lens and the third double convex lens is 0.097 mm, and the air gap between the third double convex lens and the second double concave lens is 0.027;
[0015] Each lens of the sun sensor optical system satisfies the following conditions: -0.45 < f1 / f11 < -0.4; -0.16 < f1 / f12 < -0.13; 0.06 < f1 / f13 < 0.09; -0.009 < f1 / f14 < -0.006; 0.010 < f1 / f15 < 0.070; 0.3 < f1 / f16 < 0.6; 0.27 < f1 / f17 < 0.45; 0.3 < f1 / f18 < 0.55; -0.5 < f1 / f19 < 0.35; where f1 is the focal length of the sun sensor optical system, f11 is the focal length of the first mirror, f12 is the focal length of the second mirror, f13 is the focal length of the first positive crescent lens, f14 is the focal length of the negative crescent lens, f15 is the focal length of the double concave lens, f16 is the focal length of the double convex lens, f17 is the focal length of the second double convex lens, f18 is the focal length of the third double convex lens, and f19 is the focal length of the second double concave lens.
[0016] Furthermore, the first positive crescent lens is made of glass H-ZF1, the negative crescent lens is made of glass H-ZK3, the double concave lens is made of glass H-LA3B, and the double convex lens is made of glass H-ZK11; the second double convex lens is made of glass H-ZK9B, the third double convex lens is made of glass H-ZK21, and the second double concave lens is made of glass H-ZF3.
[0017] Furthermore, the focal length of the star sensor optical system is 18.99, the total length of the lens is 68.75 cm, the spectral range is 0.45 μm to 0.75 μm, the system aperture value is 5, and the half field of view is 7.5°.
[0018] Furthermore, the star sensor optical system is sequentially provided with a first lens group, a second lens group, a third lens group, a second aperture, and a second rear lens group along the light incident direction. The first lens group includes a second positive crescent lens. The second lens group is composed of a first lens, a second lens, and a third lens. The third lens group is composed of a fourth lens, a fifth lens, a sixth lens, and a seventh lens. The second rear lens group is composed of an eighth lens, a ninth lens, and a tenth lens;
[0019] The thickness of the second positive crescent lens is 4.853 mm, the air gap between the second positive crescent lens and the first lens is 18.535 mm, the air gap between the third lens and the fourth lens is 10.554 mm, the air gap between the seventh lens and the second aperture is 0.083 mm; the air gap between the eighth lens and the second aperture is 0.247 mm;
[0020] Each lens of the star sensor optical system satisfies the following conditions: 0.15 < f2 / f21 < 0.4; -0.18 < f2 / f22 < -0.15; 0.5 < f2 / f23 < 0.8; -0.5 < f2 / f24 < -0.2; 0.3 < f2 / f25 < 0.7; -0.4 < f2 / f26 < -0.1; -3 < f2 / f27 < -1; 1.2 < f2 / f28 < 3.6; 0.5 < f2 / f29 < 2.5; 1.5 < f2 / f210 < 2.601; 1.2 < f2 / f211 < 2.9; where f2 is the focal length of the star sensor optical system, f21 is the focal length of the second positive crescent lens, f22 is the focal length of the first lens, f23 is the focal length of the second lens B2, f24 is the focal length of the third lens, f25 is the focal length of the fourth lens, f26 is the focal length of the fifth lens C2, f27 is the focal length of the sixth lens, f28 is the focal length of the seventh lens, f29 is the focal length of the eighth lens, f210 is the focal length of the ninth lens, and f211 is the focal length of the tenth lens.
[0021] Furthermore, the second positive crescent lens is made of glass H-K9L, the first lens is made of glass H-K51, the second lens is made of glass H-K9L, the third lens is made of glass H-ZF4AGT, the fourth lens is made of glass H-ZF1, the fifth lens is made of glass H-ZK3, the sixth lens is made of glass H-LAF3B, the seventh lens is made of glass H-ZK11, the eighth lens is made of glass H-ZK9B, the ninth lens is made of glass H-ZK21, and the tenth lens is made of glass H-ZF3.
[0022] A multi-configuration optimization method applied to the optical system of the all-weather space optical sensor described above includes the following steps:
[0023] Establish an initial structure: Set multiple configurations corresponding to the working modes of the sun sensor and the star sensor respectively;
[0024] Constrain aberrations and optimize performance: Use operands to constrain aberrations and balance the performance of the sun sensor and star sensor optical systems through global optimization;
[0025] Balance energy and distortion: Set weight functions for the optical systems of the sun sensor and the star sensor respectively to dynamically balance the energy concentration and optical distortion of the system.
[0026] Compared with the prior art, the beneficial effects of the present invention are:
[0027] Through the design of an integrated optical structure, the present invention meets the synchronous detection requirements of a sun sensor and a star sensor, and constructs a composite optical navigation mechanism with all-day operation, high precision, and low power consumption. A compact optical lens is provided, and multiple configurations are optimized. Weight functions are set respectively for the sun sensor (strong light mode) and the star sensor (weak light mode) to dynamically balance the energy concentration and optical distortion of the system. With the innovative modular combination of refractive and reflective optical elements, high-precision synchronous detection of the sun with high irradiance intensity and star targets with low irradiance intensity is achieved under the integrated optical path at the same time, solving the problems of conjugate design of long and short focal length optical paths, aberration optimization of optical systems with different F-numbers, and the integrated configuration of optical elements in the composite system. The original serial working mode of first coarsely measuring with a sun sensor and then precisely measuring with a star sensor is optimized into a parallel working mode of the sun sensor and the star sensor. Moreover, based on the relative positions of the sun and the stars, high-precision measurement and rapid response of the spacecraft attitude can be realized. Description of the Drawings
[0028] Figure 1 It is a working principle diagram of the optical system of an all-day space optical sensor.
[0029] Figure 2 It is the overall configuration of the optical system of an all-day space optical sensor.
[0030] Figure 3 It is the configuration of the optical system of the sun sensor.
[0031] Figure 4 It is the configuration of the optical system of the star sensor.
[0032] Figure 5 It is the optical system design of an all-day space optical sensor.
[0033] Figure 6 It is the MTF of the optical configuration of the sun sensor.
[0034] Figure 7 It is the energy concentration of the optical configuration of the sun sensor.
[0035] Figure 8 It is the MTF of the optical configuration of the star sensor.
[0036] Figure 9 It is the energy concentration of the optical configuration of the star sensor.
[0037] In the figure: first reflector 1, second reflector 2, front lens group A1, first positive crescent lens A11, negative crescent lens A12, double concave lens A13, double convex lens A14, first aperture stop B, first rear lens group C1, second double convex lens C11, third double convex lens C12, second double concave lens C13, first lens group A2, second positive crescent lens A21, second lens group B2, first lens B21, second lens B22, third lens B23, third lens group C2, fourth lens C21, fifth lens C22, sixth lens C23, seventh lens C24, second rear lens group D, eighth lens D1, ninth lens D2, tenth lens D3, second aperture stop E. Detailed implementation mode
[0038] For a clearer understanding of the technical features, objectives, and beneficial effects of the present invention, the technical solution of the present invention will now be described in detail below, but it should not be construed as a limitation on the implementable scope of the present invention.
[0039] The present invention provides an all-weather space optical sensor optical system, and its working principle is as Figure 1 shown. This system consists of a 2-configuration and 3-lens group form. Among them, configuration one is the sun sensor mode, and configuration two is the star sensor mode, and the two share a common optical path correction lens group. The sun sensor mode includes a sun sensor front lens group, which is composed of a convex mirror and a concave mirror. The convex mirror is a spherical mirror, and the concave mirror is an aspherical mirror; the star sensor mode includes a star sensor front lens group, which is composed of spherical lenses. The lens materials of the star sensor front lens group include H-K9L, H-K51, H-ZF4A, etc.; the common optical path correction lens group is also composed of spherical lenses. The lens materials of the common optical path correction lens group include H-ZF1, H-ZK3, H-LAF3B, H-ZK11, H-ZK9B, H-ZK21, H-ZF3, etc.
[0040] Next, the optical path working mode of the system is introduced in detail as follows: In different field of view ranges, the optical paths of the sun sensor mode and the star sensor mode respectively collect different spatial lights through their respective front lens groups, and finally image within the range of the visible light detector through the common optical path correction lens group. Specifically, the sunlight signal is collected by the front lens group of the sun sensor mode, with a clear aperture not greater than 2 mm and a collection range of half field of view angles from 40° to 80°. The common optical path correction lens group focuses on correcting aberrations such as astigmatism, field curvature, and θ distortion of the system to achieve clear imaging on the visible light detector, with the half length range of the imaging line field of view being 3.5 mm to 6.5 mm; the starlight signal is collected by the star sensor front lens group of the star sensor mode, with a clear aperture not less than 5 mm and a collection range of half field of view angles from 0° to 7.5°. The common optical path correction lens group focuses on correcting aberrations such as spherical aberration, coma, and astigmatism of the system to achieve clear imaging on the visible light detector, with the half length range of the imaging line field of view being 0 mm to 2.5 mm.
[0041] The present invention conducts a common optical path design for systems with different focal lengths, different F-numbers, and different optical fields of view. Figure 2 It shows the overall configuration of the all-weather space optical sensor optical system. The specific structures of the sun sensor optical system and the star sensor optical system are described separately below.
[0042] The specific parameters of the sun sensor optical system (corresponding to the optical system configuration of the sun sensor mode, see Figure 3 ) are as follows: the focal length is 4.75, the total lens length is 55.79 cm, the spectral range is 0.45 μm to 0.75 μm, the system aperture value is 2, and the half field of view is 40° to 80°.
[0043] The sun sensor optical system is sequentially provided with a first reflecting mirror 1, a second reflecting mirror 2, a front lens group A1, a first diaphragm B, and a first rear lens group C1 along the light incident direction. The front lens group A1 is composed of a first positive crescent lens A11, a negative crescent lens A12, a double concave lens A13, and a double convex lens A14. The first rear lens group C1 is composed of a second double convex lens C11, a third double convex lens C12, and a second double concave lens C13.
[0044] The air gap between the front lens group A1 and the first diaphragm B is 0.083 mm, and the air gap between the first diaphragm B and the first rear lens group C1 is 1.693 mm. The air gap between the first positive meniscus lens A11 and the negative meniscus lens A12 is 1.341 mm, the air gap between the negative meniscus lens A12 and the biconcave lens A13 is 0.405 mm, and the air gap between the biconcave lens A13 and the biconvex lens A14 is 0.324 mm; the air gap between the second biconvex lens C11 and the third biconvex lens C12 is 0.097 mm, and the air gap between the third biconvex lens C12 and the second biconcave lens C13 is 0.027.
[0045] The first positive meniscus lens A11 is made of glass H-ZF1, the negative meniscus lens A12 is made of glass H-ZK3, the biconcave lens A13 is made of glass H-LA3B, and the biconvex lens A14 is made of glass H-ZK11; the second biconvex lens C11 is made of glass H-ZK9B, the third biconvex lens C12 is made of glass H-ZK21, and the second biconcave lens C13 is made of glass H-ZF3.
[0046] Each lens of the sun sensor optical system satisfies the following conditions: -0.45 < f1 / f11 < -0.4; -0.16 < f1 / f12 < -0.13; 0.06 < f1 / f13 < 0.09; -0.009 < f1 / f14 < -0.006; 0.010 < f1 / f15 < 0.070; 0.3 < f1 / f16 < 0.6; 0.27 < f1 / f17 < 0.45; 0.3 < f1 / f18 < 0.55; -0.5 < f1 / f19 < 0.35; where f1 is the focal length of the sun sensor optical system, f11 is the focal length of the first mirror 1, f12 is the focal length of the second mirror 2, f13 is the focal length of the first positive meniscus lens A11, f14 is the focal length of the negative meniscus lens A12, f15 is the focal length of the biconcave lens A13, f16 is the focal length of the biconvex lens A14, f17 is the focal length of the second biconvex lens C11, f18 is the focal length of the third biconvex lens C12, and f19 is the focal length of the second biconcave lens C13. In this sun sensor optical system, the convex mirror is a spherical mirror, the concave mirror is an aspherical mirror, and the rest are spherical lenses.
[0047] The specific parameters of the star sensor optical system (for the optical system configuration corresponding to the star sensor mode, see Figure 4 ) are: the focal length is 18.99, the total length of the lens is 68.75 cm, the spectral range is 0.45 μm to 0.75 μm, the system aperture value is 5, and the half field of view is 7.5°.
[0048] The star sensor optical system is successively provided with a first lens group A2, a second lens group B2, a third lens group C2, a second aperture E, and a second rear lens group D along the light incident direction. The first lens group A2 includes a second positive crescent lens A21. The second lens group B2 is composed of a first lens B21, a second lens B22, and a third lens B23. The third lens group C2 is composed of a fourth lens C21, a fifth lens C22, a sixth lens C23, and a seventh lens C24. The second rear lens group D is composed of an eighth lens D1, a ninth lens D2, and a tenth lens D3.
[0049] The thickness of the second positive crescent lens A21 is 4.853 mm. The air gap between the second positive crescent lens A21 and the first lens B21 is 18.535 mm. The air gap between the third lens B23 and the fourth lens C21 is 10.554 mm. The air gap between the seventh lens C24 and the second aperture E is 0.083 mm. The air gap between the eighth lens D1 and the second aperture E is 0.247 mm.
[0050] The second positive crescent lens A21 is made of glass H-K9L. The first lens B21 is made of glass H-K51. The second lens B22 is made of glass H-K9L. The third lens B23 is made of glass H-ZF4AGT. The fourth lens C21 is made of glass H-ZF1. The fifth lens C22 is made of glass H-ZK3. The sixth lens C23 is made of glass H-LAF3B. The seventh lens C24 is made of glass H-ZK11. The eighth lens D1 is made of glass H-ZK9B. The ninth lens D2 is made of glass H-ZK21. The tenth lens D3 is made of glass H-ZF3.
[0051] Each lens of the star sensor optical system satisfies the following conditions: 0.15 < f2 / f21 < 0.4; -0.18 < f2 / f22 < -0.15; 0.5 < f2 / f23 < 0.8; -0.5 < f2 / f24 < -0.2; 0.3 < f2 / f25 < 0.7; -0.4 < f2 / f26 < -0.1; -3 < f2 / f27 < -1; 1.2 < f2 / f28 < 3.6; 0.5 < f2 / f29 < 2.5; 1.5 < f2 / f210 < 2.601; 1.2 < f2 / f211 < 2.9; where f2 is the focal length of the star sensor optical system, f21 is the focal length of the second positive crescent lens A21, f22 is the focal length of the first lens B21, f23 is the focal length of the second lens B2, f24 is the focal length of the third lens B23, f25 is the focal length of the fourth lens C21, f26 is the focal length of the fifth lens C2, f27 is the focal length of the sixth lens C23, f28 is the focal length of the seventh lens C24, f29 is the focal length of the eighth lens D1, f210 is the focal length of the ninth lens D2, and f211 is the focal length of the tenth lens D3. All lenses of this star sensor optical system are spherical lenses, which reduces the processing difficulty of optical elements and simultaneously reduces the R & D cost.
[0052] The present invention also provides a multi-configuration optimization method applied to the optical system of the above all-time space optical sensor. First, an initial structure is established, and multiple configurations are set to correspond to the working modes of the sun sensor and the star sensor respectively. Then, operands (such as MTFA, DIMX) are used to constrain aberrations, and the performance of the sun sensor and the star sensor optical systems is balanced through global optimization. Weight functions are respectively set for the optical systems of the sun sensor (strong light mode) and the star sensor (weak light mode) to dynamically balance the energy concentration and optical distortion of the system to meet the high-precision imaging requirements, thereby achieving high-precision measurement of the spacecraft attitude and rapid attitude response.
[0053] The following describes the specific implementation of the present invention in detail with reference to specific embodiments.
[0054] Embodiment 1: All-time space optical sensor optical system;
[0055] The present invention conducts a common optical path design for systems with different focal lengths, different F-numbers, and different optical fields. The designed all-time space optical sensor optical system is as Figure 5 shown. Double optical paths are imaged on the same detector. The specific parameters of the selected detector are: the number of pixels is 2048×2048, and the pixel size is 5.5μm.
[0056] 1. Overall System Overview: The all-day space optical sensor optical system in this embodiment is designed with an integrated optical structure to meet the synchronous detection requirements of the sun sensor and the star sensor, and to construct a composite optical navigation mechanism with all-day operation, high precision, and low power consumption. During the design process, an initial structure is established, and multiple configurations are set to correspond to the working modes of the sun sensor and the star sensor respectively. Aberrations are constrained using operands (such as MTFA, DIMX), and the performance of the sun sensor optical system and the star sensor optical system is balanced through global optimization. At the same time, the system adopts multiple configuration optimizations, and weight functions are set for the optical systems of the sun sensor (strong light mode) and the star sensor (weak light mode) respectively to dynamically balance the energy concentration and optical distortion of the system, thereby achieving high-precision measurement of the spacecraft attitude and rapid attitude response.
[0057] 2. Sun Sensor Optical System (Configuration 1, refer to Figure 3 );
[0058] Design parameters: The focal length is 4.75 mm; F / # is 2.39; The lens group is configured with 11 lenses, including 4 mirrors, achieving a spectral range of 0.45 μm to 0.75 μm, and a semi-field of view of 40° to 80°; The aperture stop is placed behind the 6th lens, and can cooperate with the sunshade to jointly suppress stray light (the dynamic range of the sun sensor is increased to 120 dB).
[0059] Performance indicators are as follows:
[0060] Imaging quality: The weight is biased towards the visible light MTF (the average MTF of the full field of view > 0.6 @ 30 lp / mm), which can meet the clear imaging requirements of a high-precision sun sensor. Refer to Figure 6 .
[0061] The energy concentration is better than 0.7 within the 3×3 pixel range @ the radius of the 8.25 μm blur circle, which can meet the energy detection requirements of a high-precision sun sensor. Refer to Figure 7 .
[0062] 3. Star Sensor Optical System (Configuration 2, refer to Figure 4 );
[0063] Design parameters: The focal length is 18.99 mm; F / # is 3.8; The lens group is configured with 11 lenses, and the aperture stop is placed behind the 7th lens, achieving a spectral range of 0.45 - 0.75 μm, and a semi-field of view of 0° to 7.5°.
[0064] Performance indicators are as follows:
[0065] Imaging quality: The weight is biased towards the visible light MTF (the average MTF of the full field of view > 0.85 @ 30 lp / mm), which can meet the clear imaging requirements of a high-precision star sensor. Refer to Figure 8。
[0066] The energy concentration is better than 0.9@8.25μm diffusion circle radius within the range of 3×3 pixels, which can meet the requirements for the detection energy of high-precision star sensors. Refer to Figure 9 。
[0067] The present invention has significant advantages, and its innovation can be more prominent through comparison. The detailed comparison is shown in Table 1 as follows:
[0068] Table 1 Comparison Table of the Prior Art and the Present Invention
[0069]
[0070] The above is only the preferred implementation mode of the present invention. It should be noted that for those skilled in the art, without departing from the concept of the present invention, several deformations and improvements can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the implementation effect of the present invention and the practicality of the patent.
Claims
1. An optical system of an all-weather space optical sensor, characterized in that, It includes Configuration 1 and Configuration 2. Configuration 1 is the sun sensor mode, and Configuration 2 is the star sensor mode. They share a common optical path correction lens group. The sun sensor mode includes a sun sensor front lens group, which is composed of a convex mirror and a concave mirror. The convex mirror is a spherical mirror, and the concave mirror is an aspherical mirror. The star sensor mode includes a star sensor front lens group, which is composed of spherical lenses. The common optical path correction lens group is composed of spherical lenses. The sunlight signal is collected by the front lens group of the sun sensor mode. The clear aperture is not greater than 2 mm, and the collection range is a half field of view angle of 40° to 80°. The aberration of the system is corrected by the common optical path correction lens group to achieve clear imaging on the visible light detector. The half length range of the imaging line field of view is 3.5 mm to 6.5 mm. The starlight signal is collected by the star sensor front lens group of the star sensor mode. The clear aperture is not less than 5 mm, and the collection range is a half field of view angle of 0° to 7.5°. The aberration of the system is corrected by the common optical path correction lens group to achieve clear imaging on the visible light detector. The half length range of the imaging line field of view is 0 mm to 2.5 mm.
2. The optical system of the all-day space optical sensor according to claim 1, characterized in that The focal length of the sun sensor optical system is 4.75, the total lens length is 55.79 cm, the spectral range is 0.45 μm to 0.75 μm, and the system aperture value is 2, and the half field of view is 40° to 80°.
3. The all-day space optical sensor optical system according to claim 2, characterized in that The sun sensor optical system is sequentially provided with a first mirror, a second mirror, a front lens group, a first aperture, and a first rear lens group along the light incident direction. The front lens group is composed of a first positive crescent lens, a negative crescent lens, a double concave lens, and a double convex lens. The first rear lens group is composed of a second double convex lens, a third double convex lens, and a second double concave lens. The air gap between the front lens group and the first aperture is 0.083 mm, and the air gap between the first aperture and the first rear lens group is 1.693 mm. The air gap between the first positive crescent lens and the negative crescent lens is 1.341 mm, the air gap between the negative crescent lens and the double concave lens is 0.405 mm, and the air gap between the double concave lens and the double convex lens is 0.324 mm. The air gap between the second double convex lens and the third double convex lens is 0.097 mm, and the air gap between the third double convex lens and the second double concave lens is 0.
027. Each lens of the sun sensor optical system satisfies the following conditions: -0.45 < f1 / f11 < -0.4; -0.16 < f1 / f12 < -0.13; 0.06 < f1 / f13 < 0.09; -0.009 < f1 / f14 < -0.006; 0.010 < f1 / f15 < 0.070; 0.3 < f1 / f16 < 0.6; 0.27 < f1 / f17 < 0.45; 0.3 < f1 / f18 < 0.55; -0.5 < f1 / f19 < 0.35; where f1 is the focal length of the sun sensor optical system, f11 is the focal length of the first mirror, f12 is the focal length of the second mirror, f13 is the focal length of the first positive crescent lens, f14 is the focal length of the negative crescent lens, f15 is the focal length of the biconcave lens, f16 is the focal length of the biconvex lens, f17 is the focal length of the second biconvex lens, f18 is the focal length of the third biconvex lens, and f19 is the focal length of the second biconcave lens.
4. The all-weather space optical sensor optical system according to claim 3, characterized in that, The first positive crescent lens is made of glass H-ZF1, the negative crescent lens is made of glass H-ZK3, the biconcave lens is made of glass H-LA3B, and the biconvex lens is made of glass H-ZK11; the second biconvex lens is made of glass H-ZK9B, the third biconvex lens is made of glass H-ZK21, and the second biconcave lens is made of glass H-ZF3.
5. The all-weather space optical sensor optical system according to claim 1, characterized in that The focal length of the star sensor optical system is 18.99, the total length of the lens is 68.75 cm, the spectral range is 0.45 μm to 0.75 μm, the aperture value of the system is 5, and the half field of view is 7.5°.
6. The all-day space optical sensor optical system according to claim 5, characterized in that, The star sensor optical system is sequentially provided with a first lens group, a second lens group, a third lens group, a second aperture and a second rear lens group along the light incident direction. The first lens group includes a second positive crescent lens. The second lens group is composed of a first lens, a second lens and a third lens. The third lens group is composed of a fourth lens, a fifth lens, a sixth lens and a seventh lens. The second rear lens group is composed of an eighth lens, a ninth lens and a tenth lens; The thickness of the second positive crescent lens is 4.853 mm, the air gap between the second positive crescent lens and the first lens is 18.535 mm, the air gap between the third lens and the fourth lens is 10.554 mm, and the air gap between the seventh lens and the second aperture is 0.083 mm; the air gap between the eighth lens and the second aperture is 0.247 mm; Each lens of the star sensor optical system satisfies the following conditions: 0.15 < f2 / f21 < 0.4; -0.18 < f2 / f22 < -0.15; 0.5 < f2 / f23 < 0.8; -0.5 < f2 / f24 < -0.2; 0.3 < f2 / f25 < 0.7; -0.4 < f2 / f26 < -0.1; -3 < f2 / f27 < -1; 1.2 < f2 / f28 < 3.6; 0.5 < f2 / f29 < 2.5; 1.5 < f2 / f210 < 2.601; 1.2 < f2 / f211 < 2.9; where f2 is the focal length of the star sensor optical system, f21 is the focal length of the second positive crescent lens, f22 is the focal length of the first lens, f23 is the focal length of the second lens B2, f24 is the focal length of the third lens, f25 is the focal length of the fourth lens, f26 is the focal length of the fifth lens C2, f27 is the focal length of the sixth lens, f28 is the focal length of the seventh lens, f29 is the focal length of the eighth lens, f210 is the focal length of the ninth lens, and f211 is the focal length of the tenth lens.
7. The all-day space optical sensor optical system according to claim 6, characterized in that, The second positive crescent lens is made of glass H-K9L, the first lens is made of glass H-K51, the second lens is made of glass H-K9L, the third lens is made of glass H-ZF4AGT, the fourth lens is made of glass H-ZF1, the fifth lens is made of glass H-ZK3, the sixth lens is made of glass H-LAF3B, the seventh lens is made of glass H-ZK11, the eighth lens is made of glass H-ZK9B, the ninth lens is made of glass H-ZK21, and the tenth lens is made of glass H-ZF3.
8. A multi-configuration optimization method applied to the optical system of the all-day space optical sensor according to any one of claims 1 to 7, characterized in that, It includes the following steps: Establish an initial structure: Set multiple configurations corresponding to the working modes of the sun sensor and the star sensor respectively; Constrain aberrations and optimize performance: Use operands to constrain aberrations and balance the performance of the sun sensor and the star sensor optical systems through global optimization; Balance energy and distortion: Set weight functions for the optical systems of the sun sensor and the star sensor respectively to dynamically balance the energy concentration and optical distortion of the systems.