This PDF file contains the front matter associated with SPIE Proceedings Volume 11341, including the Title Page, Copyright Information, Table of Contents, Author and Conference Committee lists.

Exploring exoplanets using stellar coronagraph requires coronagraph with a contrast of 10^-10 or even lower, because the difference in light intensity between the planet and its parent star is very large. To this end, we optimized the coronagraph imaging system with Four-Quadrant Phase-Mask (FQPM) proposed by D. ROUAN et al in 2000. The FQPM has the advantages of high extinction efficiency for the coherent light from the main source, low sensitivity to atmospheric turbulence and large dynamic range. This paper proposed an apodizer with continuous transmission and a Lyot stop optimized in conjunction with the apodizer for FQPM coronagraph, which enhance the nulling ability of FQPM to achieve a high contrast ratio of 10^-12 at 1.25λ/D and a contrast of 10^-13 at larger distance. Moreover, this optimization method can optimize the non-circular symmetric mask, that is, the optimization method is two-dimensional, rather than one-dimensional optimization in the case of circular symmetry. Then we compare the joint optimization with the optimization of the apodizer only, the results show that the former has better diffraction suppression and concentrating ability than the latter, which makes the energy more concentrated and the peak signal obtained on the detector is stronger. In the follow-up work, we will continue to complete the FQPM coronagraph system, such as adding adaptive optical to correct wavefront distortion, adding considerations for manufacturing precision of optical components and so on.

Space telescopes are widely used nowadays with the development of space optics and manufacture technologies. Large aperture of telescope means better resolution and observation. However, due to the carrying capacity and outline dimension of rocket, the aperture of telescope cannot be too large. In order to get the large telescope, more and more scientists and engineers are coming to a new idea that assembling the large space telescope on orbit. First of all, the paper makes an introduction about the concepts and types of on-orbit assembly for telescope. Then paper presents some projects which are being conducted and takes one project as an example to introduce specific implementation methods of on-orbit assembly. What’s more, high precision robots are needed in this process. Therefore, paper also introduces technologies about the robots for space assembly. At last, the paper summarizes the features and technical difficulties in on-orbit assembly of large space telescope. Furthermore, the paper points out the development directions about on-orbit assembly telescope in the future, which can give some help or guidance to engineers.

SVOM-VT has entered the initial phase development stage, and encircled energy is its key performance index. In the development process, it is necessary to determine the encircled energy of the optical lens stage and the system stage. The image recording of a CCD detector includes two imaging processes: one is the pixel integration imaging process, in which the output signal of each pixel is proportional to the area integration of the incident light intensity on the surface of the pixel; the other is the discrete sampling process, in which the continuous graphical object is sampled discretely at the sampling interval of the center distance of the pixel. Based on the data of SVOM-VT, the effect of CCD under-sampling on the encircled energy of detection camera is characterized by simulation and test. Imaging process of CCD pairs of scattered speckles from the lens is a two-dimensional discrete sampling process, as well as the sampling process of discrete signals. This process will lead to low-frequency noise (under-sampling noise) in the sampling of high-frequency signals by CCD detectors, resulting in spectrum aliasing (low-frequency signal distortion) of image signals. Intuitively, the original image is broadened. When the sampling density is increased, this will not be the case.

Surface measurement by CMM is the main method in the process of large-aperture high order aspheric mirrors fabrication. Because of the existence of probe-radius error in measurement data, the achieved surface residual cannot be directly used in mirror fabrication. So the Probe-Radius Compensation Based on Aspherical Surface Reconstruction is proposed. The algorithm comes up with a high precision surface fitting model, which introduces coordinate system space deviation parameters and use this model to calculate compensation vectors to correct the probe-radius error. The experiment shows that there is only a deviation of 4nm between the corrected data and the real data and fully meets the needs of optical fabrication.

Space telescope is widely used nowadays. Reflective mirror is an important part of the space telescope. Many engineers are trying their best to make the reflective mirror lighter and lighter. Carbon fiber composite material is universally used in the field of aerospace. But there is little engineering experience about making a reflective mirror from carbon fiber. This paper will make a structure optimization about reflective mirror which is made of carbon fiber. Traditional way of structure optimization will call numerical simulation software for many times before finding the best solution. This paper uses a black box model to take the place of simulation software to do the optimization. The black box in this paper is response surface. To some extent, it is a simple type of machine learning. The response surface learns some key information and characteristics from the model which is made by simulation software. Then, the black box, response surface, can work like simulation software. The paper makes a structure optimization based on a certain kind of carbon fiber reflective mirror by the response surface. The diameter of reflective mirror which needs to be optimized in the paper is 150mm. The optimization variables are the thickness of carbon fiber plate and the position of supports. The purpose of the optimization is that the reflective mirror has small value of PV, proper fundamental frequency, small value of stress. The paper finds the best structure design at last by the method stated above. This kind of method can be used to make optimization about other similar optical structure.

Calibration of the intrinsic parameters of a star sensor before and after its launch is essential. The existing techniques have not taken the centroiding error into consideration thoroughly. Meanwhile, the calibration operation is complex. Based on the principle of the SPGD algorithm, a calibration method fully considering the star image centroiding error is proposed in this work. Simulation result indicates that the intrinsic parameters are calibrated out and kept constantly after tens of iterations. The accuracy of principle point of the proposed SPGD based method is 4 times as the IAICM. As for the focus length, the accuracy is improved by 6 times compared to the IAICM. Simultaneously, the calibration operation becomes extremely simple

Chaotic optical communication is a secure communication method which uses synchronous chaotic carrier to realize encryption and decryption. With the demand for information security increasing, chaotic encryption has been applied to space optical communication experimentally. However, due to the complexity of chaotic system design, the bit error rate (BER) of space chaotic optical communication system is much higher than that of traditional one. High BER limits the bitrate of space chaotic optical communication while bitrate is quite important since a large amount of information needs to be transmitted in space downlink. According to our previous work, introducing two diffractive optical elements (DOEs) into optical subsystem can improve transmission efficiency, which equals to increasing transmission power. In this manuscript, we further investigate the effect of DOEs on BER and propose some suggestions on BER enhancement of space downlink chaotic optical communication.

High-precision cylindrical surfaces are widely utilized in X ray telescope systems, laser systems, synchrotron radiation systems, etc. These systems put forward strict requirements on surface figure errors of cylindrical surfaces. As a supporting technique for fabrication, interferometric null test method for measuring cylindrical surfaces usually requires a Computer Generated-Hologram (CGH) as null. However, Limited by the aperture and F/number of CGHs for cylinders, large convex cylindrical surfaces with small R/number (ratio of the radius of curvature to the aperture) cannot be tested in a single measurement.Subaperture stitching along both axial direction and sagittal direction is required to acquire the full aperture surface figure map. a convex cylindrical mirror with R/3 and 350mm aperture was tested adopting our subaperture stitching test system for cylindrical surfaces. The key challenges are presented here including, subaperture stitching platform, subaperture algorithm, subaperture lattice, and the system alignment.

The trussed front structure is the important assembly for space solar telescope; compared to the other assemblies on the solar telescope, it can be easily affected by the solar heat flux. Evaluating the influence of optical performance change of trussed front structure for space solar telescope under the external loads is a key technical problem that should be taken care. Opto-mechanical integrated simulation technology as the important method to evaluate the optical performance change under the external loads, it is selected and researched to evaluate change of optical performance for solar space telescope. First, opto-mechanical simulation algorithm is studied and the interface program ISIA is developed based on the research of the algorithm. Second, the correctness validation of ISIA is validated and the validation result demonstrates that the calculation precision of ISIA is higher and to be equivalent to the Sigfit. The ISIA provides the high-precision algorithm and tool support to realize the opto-mechanical integrated analysis of space solar telescope. Third, the optical performance evaluation of space solar telescope under the certain thermal control case is carried out. Based on the opto-mechanical simulation result, the data reference is provided for the structural design of trussed front structure for the space solar telescope. Besides, the environmental adaption design is improved as well for the space solar telescope.

On the basis of analyzing the research status of spatial angle measurement methods and devices at home and abroad, a new spatial angle measurement method based on photoelectric tracking platform is proposed. The photoelectric tracking platform is installed on the target through rigid connection of mechanical structure to establish the spatial coordinate relationship between the target and the photoelectric tracking platform, and between the photoelectric tracking platform and the earth. When the spatial angle of the target changes, the tracking angle of the cooperative target plate by the photoelectric tracking platform can be used to calculate the spatial angle change of the measured target through the spatial coordinate transformation relationship between the platform and the target. Taking the measurement accuracy of artillery adjustment as an example that the spatial coordinate system is established. The mathematical model of spatial rotation angle of the measurement method is established by utilizing the coordinate transformation relationship between the measured object, cooperative target and photoelectric tracking platform. The photoelectric tracking platform, miniaturized high-precision turntable and cooperative target plate are used to construct the simulation experiment of the measurement of the spatial rotation angle of the artillery barrel. The mathematical model of spatial rotation angle is used to calculate the experimental results and analyze the experimental errors. It is proved that the mathematical model of spatial rotation angle for this method which is effective for measuring the spatial rotation angle such as the accuracy of artillery adjusting and so on.

To satisfy aberration correction in orbit for the large aperture and long focal length space telescope, propose a technical scheme for the use of the exit pupil deformable mirror. Firstly analyze the error sources on orbit and the necessity of active correction. Use Zernike polynomial to fit the wavefront aberration and set up deformable mirror influence function model of Gauss, then provide the deformable mirror control matrix and the control voltage calculation method. The simulation results show that the deformable mirror correction technique can effectively reduce the wavefront aberration of large aperture space camera in orbit. To verify the validity of the algorithms we used in the simulation, the experimental is setup and measurement results are achieved based on the laboratory adaptive optical system.

Free space optical (FSO) communication need to keep aiming and tracking each other to keep the communication link unimpeded. In this article, quadrant detector (QD) is used to measure beacon angle deviation. But due to the background light and the dark current, the precision of the direct method cannot match the requirement of the angle measurement. To solve this problem, a proposed method based on intensity modulation and Fourier-Transform is adopted to detect the beacon position accurately. We could consider use a cosine signal to modulate the intensity of beacon light at transmitting end. So the QD output photocurrents are also cosine signals with the same frequency. Then, the energy of QD output signal is concentrated at a certain frequency point, so that the signal-to-noise ratio (SNR) at the frequency is enhanced. Finally Fourier-Transform operation can detect the amplitudes of the photocurrents at the certain frequency point which correspond to the energy of the beacon light illuminated to each quadrant respectively. Therefore, we can calculate the beacon spot position accurately. Experiment results show that even when QD output SNR is only -7.66dB, the max absolute error of the proposed method is 0.016mm and is a quarter of the direct method.

This paper reports optical system of Time Domain Observatory (TIDO) for Nanjing University(NJU). TIDO is a telescope array dedicated to survey of exoplanetary science and astronomical phenomena in the time domain. TIDO consists of 6 robotic telescopes which can image 336 square degrees(SD) of the sky in once observation, outfitted for high-resolution photometry efficiently. TIDO began in 2014 and has been in operation for 4 years. Some preliminary observation has been made, but the full operation will be by the end of 2019. In this paper, we describe the optical system of TIDO, including a 1-meter primary-focus telescope with field of view (FOV) of 9 SD, three 0.3-meter improved Marcostov telescopes with FOV of 64 SD, one 0.18-meter telescopes with FOV of 144 SD, one 0.3 meter RC telescope with FOV of 0.04 SD, and present the results of initial performance simulations using ZEMAX software.

In recent years, the form of site calibration has gradually evolved from manual measurement to automated mode. The National Satellite Meteorological Centre built up Dunhuang Site Automatic Observation Radiometric Calibration Operational System (DARCOS) in 2018, which achieved initial results. Ozone content is a parameter that has a relatively large influence on the visible light calibration of solar reflection channels. In automatic calibration systems, instruments for measuring ozone content are generally not involved, climate data is used instead. For the refined requirement of the algorithm of the DARCOS, in order to improve the forward accuracy near the Chappuis absorption band, by drawing on OMI ozone content products in 2013-2018, we performed seasonal analysis of Dunhuang ozone content data and built a yearly-collected data set model. On which it was found that in February, the monthly average of the concentration of the ozone column in the Dunhuang, fluctuated very obviously. Methods of correlation coefficient and machine learning random forest were applied respectively, to judge the correlation between meteorological parameters and the Ozone Content in February. The results: the ozone content in the Dunhuang region is negatively correlated with the temperature, average vapor pressure and minimum horizontal visibility.

Indoor air turbulence had a certain degree of influence on optical testing or optical system image quality. A long optical testing path was built in tower which was one of the largest vertical towers for optical testing in China with about 23-meter high. The relevant influence characteristics were measured and studied in a specific state. First, the air turbulence was formed using air conditionings. Then, the optical wave fronts were sampled by interferometer with two conditions of undisturbed situation and disturbed situation in which the air conditioners were turned on for a while and then turned off some time and sampling was beginning. After the statistical analyzing to the sampling results, the following several evaluation results of image quality were acquired in different status, the Radius of Encircled 80% Energy (REE), the evaluation factor of modulation transfer function (MTF), the Strehl Ratio (SR), the traditional evaluation method PV/RMS value of wave fronts, and the turbulent correlation length of atmospheric r₀. The statistical calculation results showed that turbulence intensity increased and optical image quality was deteriorated after air disturbed.

It might preserve vital clues about the imprints of life and the past livability of the planet, which are important information for studying the origin and the history of the planet, of planetary rocks or soils, so the measurement of planetary rock or soil composition is a basis of planetary exploration. Most of current composition analysis of rocks or soils, based on alpha particle backscattering technique and spectrum measurement of laser excitation, has disadvantages of low measurement accuracy, large resource demand and long measurement time. So it is urgent to seek different methods to measure the rocks or soils of planetary. A few of merits are included in x-ray active excitation mode: firstly, it has good resolution ability for elements above medium quality; secondly, the detection sensitivity of elements can reduce to 10ppm. As long as anode targets are changed, the detection sensitivity of any element can be matched. JPL is developing a prototype of a new rock composition analysis instrument based on x-ray source in order to satisfy the needs of NASA Mars 2020 exploration. It is irreplaceable as the next generation of planetary rocks or soils composition analysis instrument of x-ray active excitation mode. Therefore, the core content of this paper is to develop a composition analysis instrument, which integrates miniature x-ray source with the silicon drift detector (SDD).As the key technology of x-ray active excitation mode, miniature x-ray source must meet the needs of low power consumption, self-sealing, high intensity and micro-focus spot. For this purpose, a design proposal of the miniature x-ray source is proposed and its theoretical model is established. The size of cathode structure greatly impacts on the size of the whole miniature x-ray tube on account of the simplicity structure of x-ray tubes. So compared with the traditional x-ray source, a new cathode structure is used for the sake of reducing the whole size of the miniature x-ray tube. Not only that, but the size of cathode structure has influence on the structure of filaments, the magnitude of current and the size of focal spot of x-rays. At the same time, mini focal spot is needed to enhance the resolution ratio and intensity of rocks or soils composition analysis instruments. Hence, it is indispensable to optimize the cathode structure in order to realize the miniature size and mini focal spot. A simulation model has been set up based on theoretical calculation and simulated using charged particle optics software COMSOL or SIMION. The shape and the size of x-ray tube’s cathode have been optimized so as to attain the mini focal spot. Additionally, the influence of high voltage loaded on the cathode or the filament to focal spot size has been taken fully into account. Moreover, the SDD detector is also integrated with the miniature x-ray source and the whole volume of the composition analysis instrument decreases which is beneficial to the deep space exploration.

Dual-band imaging system can effectively improve the detection and identification capability for airborne camera. To ensure the system with compact structure and without increasing the complication of the design, a catadioptric system is proposed as an alternative where the visible light and long-wave infrared (LWIR) share the mutual aperture and adding a dichroic beam splitter between the primary and secondary mirrors enables simultaneous imaging of the two bands. The common aperture is achieved by sharing a modified Cassegrain reflection structure in both bands. The entrance pupil diameter for the two bands is 148mm and their field of view (FOV) is 3°. The visible light works in the range of 0.5∼0.8μm and the focal length is 304.2mm with 2048×2048 detector, and the pixel size is 5.5μm. The LWIR works in the range of 8μm∼14μm and the focal length is 205.3mm with 1024×768 infrared detector, and the pixel size is 14μm. The system aberration is well corrected in two bands and for the performance analysis of the system in the temperature range of 20±5‡C, the design results can meet the requirements.

During process of satellite attitude control, the star sensor provides accurate attitude information for the entire control system, and then ensures the precision of following control operations and the stabilization of flight track. To these satellites in the medium and high Earth orbit, the transmittance of entire system will rapidly attenuate after suffering a long time irradiation of space particles, which leads to the inefficacy of total star sensor and inability of providing accurate attitude information for the satellite control system. This paper presents an optical system of long-life star sensor, with optical characteristics that focal length is 49.7mm, relative aperture is 1/1.18, circular field of view is 14.14°, and the spectral range is 0.5～0.8μm. That can meet the requirement of work time at least eight years in space. The optical system is designed by all spherical mirrors with an compact structure which is just composed by six lenses. the first lens of optical system is fused quartz, the other are just made of two different optical glasses. There are some advantages that its energy is more concentrated because of small dispersed spot and low chromatic aberration, it is to be the benefit of overall debugging with better adaptability to the environmental temperature, and it has the function of optical filtering that the transmittance is higher in the work range of spectrum and is lower out the work range of spectrum, which is benefit to eliminate the stray lights.

In this paper, a dual-band (visible light and SWIR) observation and imaging optical system is proposed. The system can acquire the optical characteristics of the target in the range of 900nm-1700nm by imaging. SWIR imaging not only can get the infrared characteristics of the target, but also has the ability of anti-camouflage and through-fog. It makes up for the deficiency of visible light imaging. The integrated system of visible light and SWIR can be widely used in military monitoring, forest fire prevention, geodesy and other fields, and has high practical values. The integrated system shares the front group of telescopic objective and shares the field of view. The visual observation system working in the visible band, the diameter of the entrance pupil is 24mm, the diameter of the exit pupil is 6mm, the distance of the exit pupil is more than 20mm, and the visual magnification is-4^× . The SWIR imaging system working in 900nm-1700nm, and the diameter of the pupil is 24mm, and the focal length is 117.3mm. The field of view is for the two systems. The design and analysis results show that the system has dual-channel imaging of visible light and SWIR with common field of view, which can obtain clear visual images and digital images. The quality of the visual system and the imaging system meet the needs.

As the spatial resolution, temporal resolution, and spectral resolution performance of space remote sensing optical systems continue to increase, the demand for performance in large fields of view, large relative apertures, and multiple spectral segments is increasing. Aiming at the requirements above requirements, an off-axis common aperture space remote sensing optical systems was designed whicn is based on PW method and Gaussian formula. The system adopts the combination of off-axis two-mirror, beam splitter and refractive optical system. The relative aperture of the visible spectrum is 1/8, field of view is 0.72°, working band is 450~850nm, the focal length is 320mm, and detector pixel size is 5.5μm×5.5μm; The relative aperture of detection system is 1/8, field of view is 9.8°, working band is 3~5μm, focal length is 80mm, and detector is 17μm×17μm. The modulation transfer function of imaging system is about 0.5 at 90.9lp/mm; energy distribution of detection system is higher than 80% at 34μm, confusion spot size is smaller than 34μm. The PW method is used to solve the structural parameters of the off-axis two-mirror system, zoom-in and zoo-out system are respectively spliced, the front off-axis two mirror system is shared, asemi-reverse and semi-transparent film is placed behind the secondary mirror.The optical system adopts a zoom-in lens group to realize imaging system, and adopts a zoom-out lens group to realize infrared detection system. The spatial remote sensing optical system is combined to meet the requirements, the optical system is small in size, light in weight and compact in structure.

According to the quality requirements of the nickel-phosphorus alloy coating in the soft X-ray grazing incidence cylindrical mirror, the purpose of this article is to introduce the method of chemically depositing nickel, which belongs to the mold replication method, to produce a super-smooth optical mirror. A nickel-phosphorus alloy layer was plated on an aluminum substrate, and then was fabricated into a super smooth surface by the single point diamond turning process and the fine polishing process. Then, a gold film was coated on the preformed nickel-phosphorus alloy layer. Another nickelphosphorus alloy was deposited on the gold film layer with better adhesion strength by an adapted the nickel deposited process. Then the outer layer of nickel-phosphorus alloy was demolded with the gold film. The target thickness of the deposited nickel-phosphorus alloys is 250±25 microns by the process described in this paper, which is different from the traditional method. The main formulation of the chemically deposited nickel-phosphorus alloy includes NiSO₄·6(H₂O), NaH₂PO₂·H₂O, C₆H₈O₇, CH₃COONa. The testing results of the nickel-phosphorus alloy sheets was shown that the bonding force, corrosion resistance, porosity and other parameters were in line with the requirements for mirror production.

Optical design of a small reflecting telescope for use in a 1U CubeSat mission is reported in this study. A Ritchey-Chretien with field correction lens type telescope for earth observation techniques is adopted in this design. The primary mirror and secondary mirror are circular apertures with 70-mm and 21-mm in diameter. The effective focal length is 390-mm operated at 600-km altitude. A commercial 2560 × 2160 CCD image sensor CIS2521 with a pixel size of 6.5 μm is applied, which capture a 25km swath area. The ground resolution is better than 10m for CubeSat application. The MTF is expected to be about 0.3 at Nyquist frequency at 77lp/mm. The tolerance analysis is performed for further understanding on fabrication and assembly errors. In order to reduce the telescope size, the optical system uses a reflective optical system, and the circuit board is arranged behind the system and above. The telescope envelope size(all contained) is less than 96mm × 90mm × 90mm and the weight is approximately 600g. At present, the aspherical primary mirror has completed the processing and assembly.

The sources of stray light were briefly introduced and the necessity of stray light suppression was analyzed. Strong stray light often directly affected the performance of space debris detection camera and even invalidated it. Therefore, the application of stray light suppression in space debris detection camera was particularly important. The design of stray light suppression for space debris detection camera using baffle was proposed. On the basis of re-searching the source of stray light, the influences of the edge width of the baffle rings and the surfaces coating treatment scheme on the stray light suppression ability were finally determined. The stray light suppression ability of the baffle was greatly improved by exploring the limit of the mechanical processing of the baffle ring and optimizing the surface coating treatment method of the inner cavity of the baffle. At the same time, the stray light flow channel inside the optical system was optimized. The critical surfaces inside the optical system were found. After removing the critical surfaces, the stray light suppression design results showed the stray light rejection ratio reached 10-7 finally when off-axis angle was larger than 35°. The flares appearing on the detector disappeared completely in the experiments, and the signal-to-noise ratio was higher. The stray light suppression optimization obtained good results, which could better satisfy the requirements of space debris detection.

This paper presents a method of detecting high-speed moving targets with single light source and dual frequency laser coherence.Due to the influence of cutoff response frequency of detector, the dynamic range of velocity measurement in traditional single-frequency coherent detection system is limited, and the velocity measurement of high-speed moving target cannot be realized. In this paper, six signal components are generated by four-light coherent mixing, one of which is the difference between the fixed frequency shift and the doppler frequency shift. The simulation verifies the feasibility of the method proposed in this paper, which has the characteristics of small data collection, large dynamic range, high precision and good real-time performance of the system, and improves the theoretical guidance of the method for further high-speed target detection research.

Aiming at the problem of irregular wrinkled surface on space objects, which cannot be described accurately by 3D model, then it is proposed to use the Lambert model instead of BRDF model to describe the scattering characteristics of the coating materials. In order to verify the correctness of this assumption, the photometric data of a satellite scale model was obtained from simulation calculation and experimental measurements using two sets of the same STK (Satellite Tool Kit) scenarios. Based on the material proprieties and orbit characteristics of space object, the numerical photometric model was built. Photometric measurement of the scale model was conducted in the dark laboratory. The RMSEs(Root Mean Square Errors) of the simulated and measured magnitude are 0.187 and 0.641 based on Lambert model in two different scenarios, while the RMSEs are 0.875 and 1.060 based on BRDF model. The results indicate that the simulation results base on Lambert model fit better with the experimental results than BRDF model.

The optical surface error is one of the crucial factors to guarantee the image quality of space telescopes. The growing of aperture and pursuing of lightweight structure result in a relatively lightweight and flexible telescope mirror, whose surface figure is vulnerable to micro-vibration disturbances. Unfortunately, there are a variety of disturbances in space, such as control moment gyroscopes, momentum wheels, and cryocoolers. In order to investigate the dynamic optical surface error result from disturbances, a method based on mode superposition theory and Zernike polynomials (ZPs) fitting is proposed. On the basis of normal mode theory, the responses of an opto-mechanical structure under forced excitations can be approximated by the sum of a series of single normal modes of the system. Meanwhile, for each mode shape of an optical surface, it can be fitted as a linear combination of ZPs, which are typically used to describe optical surface errors and represent the aberrations of optical systems. Therefore, the dynamic Zernike coefficients can be computed by the superposition of the Zernike coefficients of each single mode shape. From the combination of normal mode theory and ZPs fitting technique, the relationship between the dynamic responses of optical surface error and micro-vibration disturbances is established. So, the influence of micro-vibration on the aberrations of optical system can be predicted straightforwardly. Finally, an example is given to show the effectiveness of the proposed method.

The solar simulator can accurately simulate the collimation, uniformity and spectral characteristics of solar radiation, and has high spatial heat flow simulation accuracy. It is mainly used for spacecraft thermal balance test, thermal coating property test and material aging test, which can effectively test the satellite's light irradiation and verify the thermal design of the spacecraft. The solar simulator's photoelectric conversion test using a solar simulator can improve the reliability of satellite operation. This paper introduces the successful solar simulator in recent years, expounds the main working principle of the solar simulator, and introduces the optical structure and basic working principle of the optical integrator of the key components in the solar simulator component. An optical integrator component of a solar simulator is designed, which is mainly applied to large and medium-sized solar simulators. By optimizing its design, the uniformity of illumination of the solar simulator can be effectively improved. The design is primarily analyzed in terms of optics, mechanics and cooling. First, the design and calculation of the structure and cooling are performed according to the optical design. Thermal analysis of the optical structure was performed by mechanical software, and simulation of a medium-sized solar simulator was performed using LIGHTTOOLS optical software. The results show that the integrator can make the radiation non-uniformity of the medium-sized solar simulator reach ±5%, which can effectively improve the performance of large and medium-sized solar simulators.

Large-aperture optics mirror is one of the high resolution space camera’s key components. The mirror surface shape accuracy which is subjected to external loadings can be obtained through fitting mirror surface shape. Zernike polynomials is widely used in fitting mirror surface shape due to the outstanding advantages, such as high precision and good convergence.Two methods of fitting mirror surface shape via Zernike polynomials are introdeced in this paper, namely, mirror surface deformation fitting and mirror surface shape fitting directly. Taking spherical mirror for example, the relation between the number of terms in Zernike polynomials and the fitting precision is investigated. During fitting mirror surface shape, the constructed normal equations are ill-conditioned. Reliable results cannot be obtained via the normal equation method. Singular value decomposition (SVD) method is presented to solve the abnormal equations in this paper. Through calculating the PV value and the RMS value between the fitting mirror surface and the standard spherical mirror surface, the influence of Zernike polynomials terms on the fitting precision is investigated. In the end, a design example is tested to show effectiveness of the proposed method. By fitting a deformed spherical mirror surface shape under the load condition of 1g gravity using 28-term Zernike polynomials, achieving the fitting residual, the PV value is 19.7nm and the RMS value is 3.97nm.

The detection of exoplanets is a hot topic in international astronomy nowadays. The methods of exoplanets detection are mainly divided into indirect detection and direct imaging. Direct imaging of exoplanets is being pursued by a number of research groups around the world. In this paper, the research status of space-based direct imaging technologies for exoplanets detection is reviewed, and the advantages and disadvantages of related technologies are analyzed and summarized. The most advantageous and promising space-based nulling interferometry technologies are described in detail, including some laboratory verification studies based on ground-based astronomical telescopes. With the continuous development of spacecraft micro-Newton propulsion and high-precision positioning control, ultra-high-precision laser measurement, adaptive optics, integrated optics, etc., space-based direct imaging technologies for exoplanets detection will continue to make breakthroughs.

An ultra-high resolution space target detector is essential for the exploration of the outer space of the Earth. The development of high-resolution space target detection system has become the key. All the indicators of the lens designed by ZEMAX can meet the design requirements and meet the imaging quality. However, whether the actual image quality of the assembled machine can meet the image quality requirements of the design often depends on the eccentricity level of the later adjustment, and the eccentricity affects the consistency of the optical axis, resulting in an asymmetrical aberration of the off-axis field of view. The image quality is degraded. However, when the optical system is eccentrically adjusted, the eccentricity of the system needs to be reflected by the underlying lens and amplified continuously, which is not conducive to the analysis of the system eccentricity error. A reasonable set of adjustment methods can improve the overall performance of the ultra-high resolution optical system. During the assembly of the lens group, the center deviation of each mirror surface above the mirror surface will affect the center deviation measurement difference of the mirror surface to be tested. In this paper, based on the reflection center deviation detector, the lens assembly eccentricity model is established, and the vertical axis magnification of the optical system composed of all the mirrors above the mirror surface and the optical system imaging of all the mirror surfaces above the mirror surface are analyzed. After the ball. According to the lens assembly eccentricity model theory, the existing high-resolution spaceborne camera is used to carry out the adjustment analysis, and the adjusted system eccentricity error meets the design requirements, and the MTF at the 110 pm/mm field after the adjustment is measured. The value is 0.35, and the MTF of the 0.6 field of view at 110 lp/mm is 0.3, which basically reaches the theoretical value of the design. The overall assembly adjustment effect is good, which provides a basis for the design and implementation of the optical system's adjustment scheme, and realizes the 25 million-pixel high-resolution imaging of the optical system. This lens assembly eccentricity model effectively controls the optical system eccentricity and improves the optics. The efficiency of the adjustment.

Epoxy adhesives are widely used in opto-mechanical joints for large optics. Much work has been done for bonding, fabricating and testing TMT M3, which is to be fabricated in CIOMP. General bonding procedures are introduced, specimen testing is taken for strength values, lower strength limit are predicted for application safety and stability. Based on these work, a 1/4 scaled prototype of the M3 and two dangerous optics at 1.5 m level for a large Fizeau interferometer to test M3 are successfully bonded, with some details given about the locating precision of the support pads. Results showed lower strength limits of tensile 51/shear 70 MPa, namely safety factors of 6 and 17 for the two optics respectively, considering stress concentration. Additionally, nominal strength limits of tensile 6. 7/shear 7.0 MPa at 99.95% reliability were expected. The team is in good readiness for M3 production.

To minimize the assembly stress and thermal stress introduced by the support structure, and ensure the high surface accuracy and high thermal stability of space mirror. An ultra-lightweight design of secondary mirror was carried out for some space remote sensor, and three tangential bipods were used for quasi-kinematic support. Firstly, the design principle of quasi-kinematic support structure was investigated, and advantages of bipod kinematic support were analyzed from the angle of degree of freedom decoupling. Based on structure designed above, the finite element model was established. Taking surface accuracy of the mirror as optimization objectives, the integrated optimization method was adopted to extract the structural parameters with high sensitivity on the surface accuracy in the flexible support structure, and parameters optimization design was carried out. Finally, the static and dynamic characteristics of the optimized mirror assembly were analyzed. The analysis results showed that the surface shape accuracy (RMS) of the mirror assembly is better than 1 nm under a load case of 1g gravity when the optical axis is level. Surface accuracy (RMS) is better than 2 nm under the load case of 4℃ uniform temperature rise. The first-order natural frequency of the secondary mirror assembly is 587 Hz. The optimized mirror support structure can well unload the additional deformation caused by the support structure, and has good dynamic stiffness, which verifies that the designed mirror and its support structure are reasonable, and the optimization design method is reliable. This paper provides a reference and idea for the design of flexible support structure of space mirror.

In this paper, we study the performance of serial relay coherent OFDM free space optical (FSO) communication system by quadrature phase shift keying(QPSK) modulation under strong atmospheric turbulence conditions. The relay assisted FSO system adopts decode and forward (DF) relaying protocol between source and destination of relay assisted link. Considering the joint effect of the light intensity flicker of the atmospheric turbulence, the loss of the path and the transmitter and receiver's pointing error on the atmospheric channel fading model, the closed form expressions of the outage probability and the symbol error rate (SER) of the system under the negative exponential distribution and the K distribution model is derived respectively. The effects of key factors such as the number of system hops, the number of subcarriers and average signal-to-noise ratio (SNR) on the outage and SER performance of the multihop OFDM FSO system are analyzed by simulation.

The shooting mode of camera system has evolved from fixed focus to zoom photography. And compared with the fixed-focus photography, the zoom system not only has fast field of view switching function, but also has a strong ability in the pursuit of extreme detail resolution. The newly proposed linear motor-driven zoom technology completely eliminates some inherent drawbacks of the traditional method. Based on this method, this paper focuses on an achievable mechanical structure of linear zoom camera. The relative positions of the four lens components are reasonably arranged, and two stepping motors are selected as the power sources. Modal analysis is used to ensure that the fundamental frequency of optimized system is reasonable. The experimental results show that the fundamental frequency is increased from 310.63 Hz to 544.4 Hz, so the optimized structure can avoid the oscillation frequency of external devices. Considering the harsh engineering environment of zoom camera, the thermal deformation and displacement parameters under the impact of high and low temperature loads need to be tested urgently. According to the total length of this system and deformation of the front and rear fixed groups, we can roughly get the offset value of the optical axis. The final analysis results show that the off-angle of the optical axis in the specified direction does not exceed 50 μrad, and initially meets the design specifications

Stray light severely affecting the performance of the spatial optical systems,the baffle as a kind of major measure that can effectively suppress stray light.Optimizing the internal structure of the baffle and choosing the appropriate material for the baffle are of great significance for improving the performance of the space optical systems.This paper proposes a structure design scheme of novel baffle based on the horn tube effect.This paper establishes a mathematical model for the structure of the horn tube, and uses MATLAB software to carry out the programming simulation to analyze the influence of different structural parameters on the number of reflections of the inner wall of the horn tube under different off-axis angles of the light source.The horn tube was applied as the structure of stray light suppression to a cylindrical baffle, and a three-dimensional model was built by using Solidworks software and imported into TracePro software to analyze the capability of suppressing stray light.Comparing the vertical vane with the horn tube , the results show that the horn tube as the vane has the better effect to suppress stray light,increased efficiency by nearly 50%.

When a space infrared camera has a higher temperature sensitivity , the more tiny temperature information it can record in the imaging data. High sensitive infrared camera takes an important role in observation of urban and sea targets and so on. A new space infrared camera system is designed based on pixel-level digital accumulation technology. The new infrared camera based on this technology realize the analog-to-digital convert of detecting signals into single detector pixel, which can reduce the noise caused by readout of analog signal markedly. This infrared system processes input signal by little capacitor packet digital-counting method，the integral capacitor plays the part of “voltage-to-frequency conversion”, which vary far from the traditional detector. The signal quantization process realized by the capacitor packet digitalcounting, every single charge packet is small, a capacitor of several fF in new system has the equal effect of a capacitor of thousands pF in traditional system, that makes the new infrared system can break the limit of integral capacitor’s physical restriction. So the new camera has the ability of achieving 1mK(0.001K) temperature sensitivity by theory without saturation electrons restriction. This ultra-high temperature sensitivity infrared camera system will break the temperature sensitivity limits of all infrared cameras on hand, and improve infrared system’s ability of distinguishing the tiny temperature a lot. The prototype camera has been manufactured and it has a 5mK NETD (Noise Equivalent Temperature Difference), the engineering feasibility of this camera system is valid. The pixel-level digital accumulation infrared camera will be an important development direction of future high-sensitivity space infrared camera technique.

In this paper, we simulate cylindrical and conical aircraft’s Doppler spectra caused by its spin. The characteristics of Doppler shift spectra and backscattered power are analyzed when the reflectance of aircraft surface material is Lambert and exponential terms. The results show that the Doppler frequency shift is doubled as well as the radius is doubled with the same height. When the radius remains unchanged and the height increases, the backscattered power increases. Compared with the Lambertian case, the backscattered power in the exponential case decreases faster with the Doppler shift from the peak and increases faster with time. These findings results can be used to detect flying targets in space.

A sparse aperture consisting of four rectangular sub-apertures for deployable mirror was presented. An R-C system is designed before analysis. The pupil function and the modulation transfer function (MTF) were calculated and analyzed. The strict expression of MTF of diffraction limited system with this aperture was given. In order to solve the problem that the minimum of MTF in partial directions are close to zero when the fill factor is high, the sub-aperture configuration is optimized based on the relationship curve between MTF minimum and sub-aperture’s length-width ratio. In this paper, the MTF evaluation indexes along with calculation methods for four rectangular sub-aperture sparse aperture structure are given, including MTF average and average MTF curve. Imaging simulation of the system shows that the resolution of the unoptimized structure is low in horizontal and vertical directions, while the image quality of the optimized structure is similarly high in all directions.

The high resolution space optical camera imaging quality was sensitive to micro-vibration both in space and on the ground test. When performing the thermal-optical test within a vacuum tank, the affiliated air compressor pump, the turbo molecular pump and other pump assembles may cause micro-vibration transmitting to the payload. Firstly, the threshold and frequency bandwidth of the camera mounting flange micro-vibration were calculated based on the cameral optics and structure rigid-body theory. Secondly, three linear accelerometers were used for micro-vibration signals acquiring, and the identification plate was used for imaging. The signals and photos were acquired at the same time during the pumps turned on and turned off separately. Finally, the vibration caused by the pump assembles were analyzed after the thermal-optical experiment process, together with the images’ MTF. It’s shown that even the vacuum tank was isolated on the ground, the affiliated s’ micro-vibration ed to the inside payload, causing a previous vibration The STD of Z axis micro-vibration signal more than 3 times from 2.1mg to 9.5mg, Exceeding the analysised threshold from 9Hz to 16Hz and near the 146Hz, the peak vealue was about 3 times of the threshold at 13 Hz, while the MTF declined little, just about 2.5%.

Transmissive membrane diffractive optic can be used in space optical telescope or long-distance sensing to reduce the size and mass of imaging system. However, images of membrane diffractive imaging system are inevitably affected by diffraction efficiency and atmospheric propagation, which leads to low utilization ratio of light energy and image blur. Clarity of this degraded data is a challenging task. In this paper, an effective post-processing method based on total-scale Retinex (TSR) is proposed to address this problem. First, we design a self-adaptive scale surround function model that is guided by the optical transmission rate to estimate illumination component. Then, we embed the estimated-illumination into Retinex model for directly estimating the final clarity component. Moreover, the proposed method is capable of quasi real-time processing video using temporal coherence. Our method extends the multi-scale Retinex model while it avoids color artifacts in transmission model that can appear due to incorrect depth estimation. The experimental results show that our approach obtains better performance than the other state-of-art methods with respect to contrast enhancement and color-cast correction.

In order to improve the processing efficiency on the basis of obtaining good surface quality for aluminum alloy mirror with the chemical mechanical polishing(CMP) method, the status between abrasives and workpiece surface is researched adopting the elastic plastic deformation and nano indentation theory. The material removal mechanism is revealed through the CMP material removal model which is established on the analysis of surface topography, particle force and removal efficiency. It is found that the discontinuous down pressure which is related to surface morphology of the polished pad has a serious influence upon removal efficiency as well as the original pressure and the rotate speed of pad. With the support of these results, a variable parameter polishing method is proposed. The actual experiment result shows that the processing time is shortened by about 64% compared with the original method on a Φ100mm plane sample in the process of roughness improvement from Ra 5.03nm to Ra 2.95nm. The validation of variable parameter CMP method is certificated.

The zoom optical system can realize continuous change of focal length in a certain range while keeping the image plane fixed and the relative aperture basically fixed.At present, the zoom system is designed to ensure the stability of the image surface mostly by mechanical compensation method, and the mechanical structure mostly uses the zoom cam as the power transmission mechanism.Good image quality and simple operation are the development direction of the cam curve design. In this paper, the mechanical compensated two-component zoom optical system is taken as an example, and the corresponding zoom cam curve is obtained by using three methods: the ray tracing method, the multi-point fitting method and ZEMAX macro. The data of image quality evaluation parameters are analyzed and the imaging quality of three cam curve fitting methods is compared.

Magnetorheological Finishing (MRF) is widely regarded as an effective means of processing aspheric optical components. We developed a MRF polishing machine based on a robot arm. Compared to the traditional MRF polishing machines, our new generation machines are more flexible, cost-effective and efficient. The basic components of were introduced and the calculating angle was transformed. We processed a flat SiC mirror and the final accuracy is 0.012λ.

As the lightwave passing through the atmosphere, the light’s path is not the uniform linear motion as well as the path has been bent, which causes the atmospheric refractive error of lightwave. As usual, two photoelectric theodolites are used to supply data for refractive error calculation. In the case of one photoelectric theodolite in the same time or the same area, the calculation method above is not suitable. This article proposes the calculation method of atmospheric refractive error based on single photoelectric theodolite which needs radar ranging to the flight target. First, station coordinate system is built and the station of photoelectric theodolite should be transformed to the system as well as the station of radar. Second, the original geocentric distance should be cut to L levels by lightwave refraction index from the station of photoelectric theodolite and the apparent distance between photoelectric theodolite and flight target is calculates. Third, the calculated geocentric distance should be cut to L levels by lightwave refraction index and the geocentric angle between photoelectric theodolite and flight target is calculated. At last, both the real elevation angle of photoelectric theodolite to the flight target and lightwave’s atmospheric refractive error are calculated by formula of elevation angle. The calculation method of atmospheric refractive error in this article only uses data of single photoelectric theodolite, as well as definite integral formulas of both apparent distance and geocentric angle are optimized, by which more accuracy error calculation of lightwave’s atmospheric refraction can be achieved.

In this paper, we mainly studied how to calculate the energy values of stars received by ground optical systems. Then according to the characteristics of the radiation spectrum of stars and the radiation spectrum of sky background light, we analyzed and selected the observation spectrum of the image-forming system. We also studied the influence of optical system design parameters, such as field of view, focal length and aperture, on detection capability. At the same time, we analyzed and calculate the limitation of the detector's dark current, readout noise and other noise factors on the ability of receiving stars. The significance of these studies is that we provide an effective theoretical basis for designing and improving ground-based photoelectric detection system for star observation during the daytime. In addition, we used digital image processing technology to process the existing observation images and improve the quality of the image. We provide several algorithms for extracting small targets in strong background. We use threshold segmentation, morphological filtering and other methods to improve the signal-to-noise ratio of the image and then improve the detection ability of the system again. According to the simulation, the target extraction accuracy can reach 1/10 pixels when the target imaging size is 4 pixels and the signal-to-noise ratio is less than 5. Improving the detection ability of photoelectric detection system, detecting more available stars and obtaining their relative position information are the important basis for star map matching and the estimation of targets’ position and gesture.

With the development of technology, research on solar flares has been gradually developed, and the corresponding detection band also involves hard X-ray. Due to the particularity of hard X-ray, the collimator is generally used to observe it. When observing the sun, the load is required to point at the sun accurately. This paper mainly introduces an optical system for precise pointing to the sun of the solar hard X-ray imager. By optimizing the design, the measurement requirements are satisfied. In addition, the design results, system ghost images and measurement accuracy are analyzed and evaluated.

Due to the large size of large-aperture aspheric mirrors and the long optical path each of them needs to inspect, the deviation of the optical axis from the structural reference cannot be accurately measured by conventional inspection means. However, as the aperture of the optical lens increases, alignment puts higher requirements on the concentricity of the optical axis of the mirror with the axis of the structure. Excessive eccentricity leads to severe consequences, including interference of the lens’ optomechanical structure, and non-adjustable misalignment. In this study, the accurate measurements of all the optical parameters of the mirror were realized by building an inspection optical path with mirror, measuring the spatial position of the apex of each optical component structure using a laser tracker, and testing the mirror through rotations. The conventional inspection methods and the inspection method of this study were simultaneously applied to the aspherical mirror with a diameter of 448 mm. Through the test results, it has been proven that the method proposed in this study is feasible.

In order to achieve more imaging modes and higher imaging efficiency, the super agile remote sensing satellite is proposed and researched. Super agile remote sensing satellite can realize maneuvering imaging with large angular velocity and large angular acceleration. It has some new characteristics, such as curved imaging trail, variable imaging parameters. In this paper, the feature and theory of maneuvering imaging are studied. The analysis model of maneuvering imaging is established to precisely analyze the complicated and time-varying imaging parameters. Based the model, the change of defocus with roll angle, the change of ground sample distance with roll angle and field of view angle , the change of resultant velocity with different angular velocity, the change of line rate with angular velocity are analyzed. Then the requirements of number of TDI, the MTF of attitude stability, the MTF of synchronization error, the MTF of drift error, are precisely analyzed. The results show that the imaging parameters will change quickly with time and space. The ground sample distance changes from 0.25m to 1.62m. The resultant velocity changes from 7.05km/s to 59.41km/s. The line rate changes from 28.24 kHz to 237.68 kHz. Consequently, super agile remote sensing satellite needs higher line rate, bigger integral number, higher drift correction accuracy and higher synchronization accuracy to improve image quality of maneuvering imaging.

In this paper, a stellar coronagraph system with wavefront correct instrument is proposed, the optical design and image quality evaluation of the system are carried out, including the optical design of the front telescope system, the collimator instrument, wavefront correcting system in coronagraph and the optical design of the imaging lens. The front system used a structure of off-axis double-mirror telescope, with a diameter of 2.4m, 16 for F, and a FoV of 10 "×10", The design requirements of the coronagraph instrument is: wavelength band is 450nm to 950nm, the detector is a EMCCD with the resolution of 1k×1k, pixel size of 13μm, the diameter of deformable mirror is 10mm. The design requirements of the imaging lens is: the optical aperture D is 5mm, F# is 15, the magnification of beam expander is 12.6 X. In this article, the coronagraph instrument system adopts the phase plate and the Lyot aperture and add the combination of the design and a deformable mirror is used to correct wavefront while a Lyot aperture is used for blocking the remnants of the star light, the introduction of the deformable mirror system can better eliminate both speckle noise and fixed optical surface error influences on imaging quality, also can correct the dynamic error.The design results show that: on the image plane, at the wavelength of requirement, the wavefront RMS value was less than 0.02λ, the result show that the wavefront error of the system reached the diffraction limit, it also means that the optical design of the whole system meet the design standard of coronagraph.

A new system has been developed for efficient calibration of modern space soft x-ray astronomical telescopes, in particular the x-ray detectors with energy and time resolution. The system provides a large-area (about 1000 cm² ), highly parallel (±1mrad/24mm), timely and spatially uniform (±5%) beam of x-ray beam. Other special features include a multianode (15 anodes and 17 filters) x-ray source and a narrower pulse (width ≤10 ns) x-ray source. There is a six-axes vacuum turntable that can be used in a wide range with high precision (0.1mm and 0.01°). In this paper, the composition, function and performance of this calibration system will be described in detail.

This article is devoted to design hyperspectral imaging optical system, which is actively used to solve practical problems in agriculture, such as detection of damage to crops by adverse meteorological phenomena, detection of damage to crops by pests and diseases, monitoring of germination of grain, detection of the situation to which weeds are distributed, etc. These devices of optical system are installed on unmanned aerial vehicles (UAV). A feature of such system is that the camera can take photographs of one area in different spectral ranges, which recognizes spectral signatures from objects and allows more detailed information in a shorter time. This article describes the searching result and the designing process of an optical system which do above characteristics possibility.

The unmanned aerial vehicle resources include subsystem resources such as sensors, weapons and communication links, in order to meet the resource scheduling and management requirements of unmanned aerial vehicle, this paper studies the resource scheduling and management mechanism of unmanned aerial vehicles from the aspects of demand analysis, functional framework and operation process. It mainly analyzes the functions and operation flow of unmanned aerial vehicle, including resource adaptation conversion, access control, access control, resource state maintenance, etc., so as to provide references for the packaging and adaptation of unmanned aerial vehicles resources and the design of resource management software.

Observation target characters can be truly reflected by multi-type sensor detect with multi-source information fusion, processing and comparison. Based on the design and application requirement of multi-type sensor for low inclination orbit satellite(hereinafter called LIO), the study on optical remote sensor’s imaging performance is carried out in this paper for LIO satellite. Due to the complex precession of the orbit, the imaging characteristics are analyzed and compared with the sun synchronous orbit including solar elevation angle, radiance at the entrance pupil, SNR, revisit period, satellite illumination azimuth angle and the angle between sun vector and bore sight vector. According to the analysis results, conclusions on optical remote sensors imaging performance of LIO can be drawn in the imaging dynamic, radiance performance, revisit efficiency, sunlight avoiding and thermal control design. The study provides a reference for the low inclination orbit satellite general design and optic remote sensor development.

In this paper, a multi-optical platform target recognition theory based on geocentric observation is proposed by studying the space debris observation model based on multiple optical platforms, and the recognition rate is over 85%. The Gaussian minimum mean square error differential correction algorithm is used to realize the target location by multiple optical observations, and the positioning accuracy reaches 14m, and the positioning accuracy tends to the accuracy of the satellite itself. It can get rid of the disadvantage that the space debris cannot be located by single optical platform, and retain its important advantages such as high accuracy and low power consumption. which lays a solid foundation for the later debris orbit determination.

With the rapid development of vacuum ultraviolet detection technology, vacuum ultraviolet spectrum radiometers are increasingly used in space detection. Vacuum ultraviolet spectrum radiometers can acquire ionospheric disturbance information, solar activity information, celestial activity information, etc. Meteorological forecasting, defense and military security play an important role in supporting data. Typical examples of vacuum ultraviolet spectroradiometers are ionospheric photometers and wide-angle aurora imagers. Many of the satellites launched in the early stage are equipped with such vacuum ultraviolet spectroradiometers. Before the launch, the vacuum ultraviolet spectrometer needs to perform calibration test on the ground to establish a corresponding mathematical relationship between the output data and the input energy. However, the current domestic calibration device for the vacuum ultraviolet spectrometer has not been established, and vacuum ultraviolet light cannot be guaranteed. The accuracy of the calibration of the spectroradiometer, which in turn affects the accuracy of the inversion data, has a serious impact on national meteorological predictions, military safety, and so on. This paper provides a vacuum ultraviolet spectrum radiometer calibration scheme, including spectral radiance brightness responsivity calibration device, wavelength accuracy calibration device, vacuum ultraviolet BRDF measurement device, etc., which can achieve spectral radiance responsiveness and wavelength to vacuum ultraviolet spectroradiometer Calibration of parameters such as accuracy, and measurement of BRDF for vacuum ultraviolet diffuse reflectors. The spectral radiance responsiveness calibration device includes a vacuum chamber system, a vacuum ultraviolet light source, a vacuum ultraviolet integrating sphere, a vacuum ultraviolet diffuse reflector, a standard radiometer, and the like. The wavelength accuracy calibration device includes a vacuum chamber system, a vacuum ultraviolet light source, a vacuum ultraviolet monochromatic spectroscopic system, a standard filter, and a vacuum ultraviolet collimating optical system. The vacuum ultraviolet BRDF measuring device includes a vacuum chamber system, a vacuum ultraviolet light source, a vacuum ultraviolet monochromatic beam splitting system, a vacuum ultraviolet collimating optical system, a high-precision two-dimensional turntable, and a vacuum ultraviolet standard detector. Through technical breakthroughs, this paper breaks through the vacuum ultraviolet standard radiometer design technology, vacuum ultraviolet diffuse reflector BRDF measurement technology, large area high uniformity vacuum ultraviolet Lambertian radiation surface design technology, and synchronous radiation based traceability technology. The content of this paper mainly includes the overall scheme of calibration equipment, subsystem scheme, test data and uncertainty synthesis. Through the analysis and calculation of the test data, it can be known from the calculation results that the uncertainty of the spectral radiance responsivity measurement of the calibration device is better than 13% (K=2), and the uncertainty of the wavelength accuracy measurement is better than 0.1 nm (K= 2), BRDF measurement angle range is better than ± 60°. Compared with the measurement technology capabilities of other domestic research units, the calibration device covers the vacuum ultraviolet band, and the measurement uncertainty can meet the calibration requirements of the domestic vacuum ultraviolet space load development unit, effectively solving the calibration problem of vacuum ultraviolet space load. Through the development of the vacuum ultraviolet spectrum radiometer calibration device, the calibration problem of the domestic vacuum ultraviolet spectrum radiometer is solved, the vacuum ultraviolet measurement technology capability of China is improved, and the development of the vacuum ultraviolet spectrum radiometer is effectively guaranteed.

JSC LZOS successfully applies Computer Generated Holograms (CGH) for testing of on- and off-axis surfaces of largedimensioned optical components, for their alignment with respect to interferometer, for defining of aspherical surface optical vertex position with respect to the geometrical center, for optical systems alignment. All this allows producing of large-dimensioned aspherical on- and off-axis astronomical and space mirrors with high accuracy.

Some experiments show that the laser propagation in the actual atmosphere will deviate from the ideal Kolmogorov model. Based on the generalized Huygens-Fresnel principle and non-Kolmogorov turbulence model, the analytical propagation expressions of partially coherent four-petal elliptical Gaussian vortex (PCEPEGV) beams in non-Kolmogorov atmospheric turbulence are derived, and the correctness of the analytical results is verified by simulation. The results show that topological charge number and coherence width play a key role in beam propagation. Large topological charge number, small beam order and large elliptical factor can alleviate the influence of atmospheric turbulence effectively and suppress mode crosstalk in orbital angular momentum mode propagation.

With the increasing of human space activities, space debris increases sharply, and this will seriously threaten the safety of spacecraft in orbit. In order to meet the requirements of spacecraft on-orbit service, space detectors can be used to identify and detect non-cooperative objects such as space debris around orbit, which will reduce the impact probability of spacecraft on-orbit and ensure the sustainable use of orbital resources. In order to improve the probability of on-orbit detection, it is necessary to conduct sufficient simulation and verification tests on the ground to ensure the effectiveness of on-orbit detection. On the basis of large cryogenic radiometric calibration optical system, a set of optical hardware-in-the-loop simulation and verification system is proposed in this paper, including large space environment simulator, large cryogenic projection system, optical target simulation system, target attitude simulator, central control system, etc. At present, the technology has been applied to the ground performance test of a space camera, which verifies the influence of target jitter on the image detection effect, and obtains a large number of experimental data, and achieves satisfactory results. In the future, this technology will be studied in depth, mainly to improve the accuracy of target simulation, expand the types of simulation targets and increase the joint validation function of the system. It will continue to be applied in the system-level performance verification of space detectors, and it will have broad application prospects and important practical significance in space on-orbit service tasks.

With the increasing demand for high resolution earth observation and the development of deep space exploration and scientific research activities, the focal length of space camera is getting longer and longer, and the aperture of space camera keeps increasing. When a large-aperture space camera is mounted on the ground, the figure and position of the mirror will change due to the gravity effect on the mirror and its supporting structure. The three-mirror coaxial (TMC) space camera has certain structural symmetry. In order to improve the reliability and efficiency, the optical axis vertical alignment technology is widely used in the world. The main content of this paper is to elaborate the design process of optical axis vertical alignment scheme for Φ1.3m TMC space camera, as well as the test verification process and results. The on-orbit wavefront of the central field of view is 0.050 λ, and the on-orbit wavefront of the edge field of view is 0.064 λ and 0.059 λ. The camera wavefront meets the design requirements, and the setting factor is better than 0.94. The optical axis vertical alignment scheme of optical axis of Φ1.3m TMC space camera is verified.

In this paper, a joint posture determination algorithm of rocket contour line and cooperative measurement ring photographed by high-speed TV in the shooting range is proposed targeting at the complex test range environment with lot of smoke and backlight. This algorithm makes up for the shortcomings of traditional algorithms in some extreme cases. The method makes use of the relative relation between the target contour edge and the measuring ring edge and the cylindrical rocket body. Even if under the poor imaging, the method can still calculate out the information about the posture of the rocket. If the method is validated with the measured data, the difference values of the calculation results are as accurate as the calculation results of the traditional methods. However, this method is better in anti-interference and has a more extensive application scope, achieving the expected purpose.

The spatial information of high-resolution remote sensing images is more abundant, and the expression of ground object information in detail is clearer. Vegetation is a component of the environment and the most important component of terrestrial ecosystems. Therefore, vegetation information extraction from remote sensing images is particularly significant. This paper takes Shanghai Pudong New Area as the research area, adopts threshold classification method and membership function classification method to extract vegetation information, and introduces normalized vegetation index as feature to extract vegetation information from WorldView-3 satellite remote sensing image. The results show that the accuracy of vegetation information extraction based on membership function classification method is higher. The classification accuracy of typical vegetation area is higher than 90%, and the Kappa coefficient is higher than 0.86, which can significantly reduce the fragmentation caused by classification. At the same time, high-resolution remote sensing images show great potential for the extraction of vegetation information in urban areas.

Complex surface optical components have been widely used in the forefront of aerospace, space exploration, military reconnaissance and modern information technology due to their advantages in improving aberrations, improving imaging quality, reducing system unit quantity and weight, reducing power loss, improving accuracy and stability. As one of the main methods to process high precision optical component, Computer controlled optical surfacing (CCOS) has also been applied in the processing of complex surfaces. However, due to the incompletely contact between the polishing pad and the surface of the workpiece especially the high-steepness and large curvature area during processing, the phenomenon of unstable removal function is generated, which leads to deterioration of surface accuracy and even flaws..In this paper, the elastic fiber modeling theory derivation, ABAQUS finite element simulation and experimental verification method are used to study the contact problem between the polishing disc and the workpiece surface and the stress distribution when processing complex curved surfaces, and the deformation layer of the polishing pad is optimized. An improved semiflexible polishing disc was used to machine a complex curved aluminum alloy mirror, which improved the surface quality while controlling the change in surface accuracy (PV value) within 10%, verifying the improved polishing disc processing. The effectiveness of complex surfaces.

A Lap-MRF process is proposed for large aperture mirrors. In Lap-MRF, a lap is used to expand the polishing area, which improves the material removal rate. Moreover, the MR fluid can be renewed continuously to ensure the stability of the material removal rate, which improves the convergence efficiency of the surface profile error. In this paper, the figuring ability of the Lap-MRF removal function is analyzed. The Lap-MRF process, which is based on surface profile filtering, is presented. Finally, a series of figuring experiments on a Φ350 mm K9 mirror are carried out. For the Lap-MRF removal function, the volume removal rate is up to 0.48 mm³ /min and the cut-off frequency is about 0.03 mm^-1 . After four times figuring using Lap-MRF, the surface profile error throughout the whole surface is improved to 4.84 λ (λ= 632.8 nm) PV (Peak-to-Valley), 0.69 λ RMS (Root Mean Square) from 25.24 λ PV, 4.31 λ RMS and its total convergence ratio of the RMS error is up to 6.32. These results verify the validity of the proposed method for large aperture mirrors.

Target Characteristic (TC) detection capability evaluation is a hotly studied topic due to its importance in the development of Optical Imaging Satellite (OIS). In this paper, we propose a method to evaluate the OIS-TC detection capability. We use Analytic Hierarchy Process (AHP) to build an Optical Imaging Satellite Target Characteristics Detection Capability Evaluation Index System (OIS-TC-DCEIS). Based on this system and the evaluation of expert, we obtain Weight Coefficient (WC) of Satellite Performance Parameter (SPP). And then, we nondimensionalize physical values of SPPs to get the Evaluation Index Values (EIV). During the process of obtaining the WC and EIV, we use experts’ experience as a reference. After that, we construct an evaluation equation to calculate the OIS-TC detection capability by using WC and EIV. As an example, we use this method to evaluate the TC detection capability of SJ-9 satellite and GF-2 satellite.

In terms of spherical vector wave functions (SVWFs) utilizing integral localized approximation method, the incident field and scattering field expansion coefficients can be derived. Using Generalized Lorenz Mie Theory (GLMT), the radiation force (RF) exerted on a single spherical particle by a LG beam is calculated. The effects of OAM states, beam waist, particle size, dielectric constants of particle and surrounding medium of axial RF have been numerically analyzed in detail.

It has been challenging for medium wave infrared (MWIR) optical imaging system to work in a large temperature range and stationary effective focal length, on account of the thermal effect of optical elements and machinery. Performances of a MWIR space remote sensor in an advanced passive thermal-free design are presented with a fronting R-C system and a rear spherical lens group. A general analytical expression for eliminating thermal defocus and chromatic aberration is obtained, and it is demonstrated that these defocus and aberrations are minimized when this MWIR space remote sensor is operated at a broadband (3um to 5um) and large temperature range (-40°C to 40°C). The ZEMAX software is used to obtain the final parameters of space remote sensor by global optimization, which realize 100% cold shield efficiency. The MWIR space remote sensor has a focal length of 2150mm, F number of 3.58, full field of view of angle of 0.4°×0.4°and pixel size of 15μm. This optical system provides a high ground sample distance (GSD) of 251m and wide single landscape width (SLW) of 251km×251km in geosynchronous orbit. The imaging quality of the space optical remote sensor is almost diffraction limited which can be inferred from metrics such as root-mean-square spot diagram, MTF, wavefront function etc.

Performances of a novel solar extreme ultraviolet (EUV) slitless imaging spectrometer in a stigmatic design are presented with an aberration-correcting flat-field holographic concave grating (HCG). The instrument is based on a conventional off-axis Maksutov telescope with aberration-corrected holographic rulings on the secondary optic. These rulings with varied line-space enable stigmatic imaging in diffracted light with a minimum number of optical elements, thereby maintaining a high system efficiency. The novel design has improved temporal resolution prominently by throwing away the slit and no scanning, either spatially or spectrally, permitting EUV spectroscopy with a high time cadence in observation of the full solar disk. In this approach all data are taken simultaneously over the whole field of view, and hence no confusion of temporal evolution with spatial or spectral variation. ZEMAX software is used to obtain the final parameters of spectrometer through global optimization and multiple configuration. The slitless imaging spectrometer possesses imaging detectors at three orders of flat-field HCG, which provides cotemporal imaging and spectroscopy with high spatial resolving element (1.8arcsec/pixel) and spectral resolving element (60mÅ/pixel) for a narrowband at 304 Å and a wide field of view (36arcmin). The performance of the resulting optical design are evaluated, and the imaging quality obtained here is excellent which can be inferred from the root-mean-square spot diagram.

The advantages of the freeform surface is obviously in optical system application: higher image quality, larger view field, simplified system and more design degrees of freedom. But, the large application of the freeform surface is limited by the difficulty of its manufacture. Measurement is the base of optical fabrication. In order to achieve the high precision freeform surface, the surface should be measured accurately. High precision freeform surface measurement technology is one of the most important problem in the field of optical fabrication. A new measurement method has been proposed which is different from the existing free-form surface measurement instruments, and it is proved in theory that can achieve high precision measurement for free-form surfaces. In this paper, a complete mathematical model is established for the probe part through ray tracing, so as to obtain the object-image relationship data of light passing through each optical element. Using the point set, the wave image of each surface is obtained, the optical path difference of the light is calculated, and the corresponding interference diagram is drawn. This process is principle verification. Contrary to the simulation process, in the process of measuring, the interferogram is obtained first, and then the deviation value is calculated.

We present program objectives and specifications for the first generation Ultra-Fast Astronomy (UFA) observatory which will explore a new astrophysical phase space by characterizing the variability of the optical (320 nm - 650 nm) sky in the millisecond to nanosecond timescales. One of the first objectives of the UFA observatory will be to search for optical counterparts to fast radio bursts (FRB) that can be used to identify the origins of FRB and probe the epoch of reionization and baryonic matter in the interstellar and intergalactic mediums. The UFA camera will consist of two single-photon resolution fast-response detector 16x16 arrays operated in coincidence mounted on the 0.7 meter Nazarbayev University Transient Telescope at the Assy-Turgen Astrophysical Observatory (NUTTelA-TAO) located near Almaty, Kazakhstan. We are currently developing two readout systems that can measure down to the microsecond and nanosecond timescales and characterizing two silicon photomultipliers (SiPM) and one photomultiplier tube (PMT) to compare the detectors for the UFA observatory and astrophysical observations in general.

Aiming at the characteristics of the large format aerial measuring camera with larger field, lower distortion and telecentric beam path, a new optical system with field of 75° and lower distortion was designed in this paper. The optical system selects inverted telephoto as the initial structure instead of symmetric structure. The optical system is all sphere and has the advantages of compactness ,long back working distance and easy to fabrication and alignment. The result shows that the focal length is 135mm,with the relative aperture of 5.2 and the field of 75°,meanwhile , the modulation transfer function(MTF)is higher than 0.3 at the 100lp/mm,the distortion is lower than 0.01%,the biggest angle of incidence on image surface is smaller than 20°. This optical system can be used for the large format aerial measuring camera.