In order to realize the observation ability of a space camera with the field of view angle greater than 120 degrees and the imaging spectrum covering 350nm~ 12500nm, the design and verification of a scanning system with large field of view and multichannel were carried out. Firstly, according to the performance indicators of the camera, the structure form of the overall scanning and imaging system was determined. Two motors were used to drive the telescope system and the half-angle mirror to rotate in the same phase respectively, and by imaging with four refractive relay optical systems in different spectral bands, the camera could achieve a wide field of view imaging covering the ultraviolet to long wavelength infrared spectral range. Secondly, based on the scanning form, the optical parameters and the system structure were designed in detail. Finally, the system was alignment, and the performance of the system were measured in experiment. The wavefront aberration of each field of view in the telescope system was better than 0.047λ (λ= 632.8nm). The scan following accuracy of the half-angle mirror was better than 10″, with a deviation of 0.01mm from the scanning axis position of the telescope system. All field of view MTFavg of the four channels were better than 0.42, meeting the indicator requirements. The results show that the design of this scanning system with large field of view and multichannel is reasonable and feasible, and has important reference value for the development of related systems.
In the process of lens with aspherical surfaces,the aspherical surfaces and spherical surfaces are usually optically processed based on the structure of the lens.There is a machining eccentricity error between the symmetry axis of the aspheric surface and the opcical axis of the lens.The inconsistency between the asymmetrical axis and the optical axis of the optical system which contains multiple aspherical lenses and has strict eccentricity requirements ,such as the adjustment tolerance is 5″, leeds to a large wave aberration,if the adjustment of optical system is relied on the traditional decentering technology. The result reduces the final imaging quality of the lens.For the high-precision installation of aspherical refraction lens which contains strict installation tolerance,based on the traditional technology that adjusts the optical axis of the lens by devices such as center deviation measuring instruments,computer simulation calculation、 optimization of structural form and reasonable setting of compensator are applied in the actual engineering.According to the system aberration and compensator sensitivity, adjust the centered lens to reduce or eliminate the system aberration.The result shows that this method can effectively correct the misalignment of the system and at the same time improve the image quality of the optical lens
To realize the fast, high-quality alignment of off-axis reflective system, a computer-aided alignment method based on high-precision extraction of optical axis and high- precision restoration of surface shape of off-axis mirror was proposed. The optical axes of the mirrors are derived by means of a zero-position compensation detection path of the off-axis mirrors, and accuracy is better than 6", realize more rapid and accurate system initial alignment. There propose a surface shape data conversion algorithm, combined with Code V, it can realize the high-precision restoration of measured surface shape data of off-axis mirror in simulation, accurately calculate and separate the influence of shape error and position misalignment on system quality, and realize the fast and high precision alignment of off-axis reflective system. This method is applied to the practical alignment of one off-axis TMA system, wave aberration RMS≤0.084λ(λ=632.8nm) after initial alignment of the system. After only once calculation and alignment, full field RMS≤0.055λ. The experiment results demonstrate that this method is feasible.
In the field of aerospace remote sensing, the errors of optical element surface shape and position misalignment are often mixed together in the off-axis reflection system, which directly affects the accuracy of simulation analysis of computer aided alignment , and reduces the quality and efficiency of the optical system alignment. In order to solve this problem, there propose a surface shape data conversion algorithm, which can convert and process the surface shape data of optical elements. Combined with Code V, we can calculate and remove the influence of the surface shape error on the image quality of the system, and achieve optical alignment of off-axis reflection system fast with high precision. Verified analysis, the accuracy of this algorithm is higher than the traditional inversion Zernike polynomial fitting method, and reduction accuracy is better than 90%. In addition, the surface shape data conversion algorithm can also achieve restore of non-circular optical elements (such as ellipse, rectangle, shading and other arbitrary shapes) in the optical simulation software with high precision, which can provide more accurate results for optical system with high precision and rapid.
For the high precision requirement of spaceborne low light remote sensing camera optical registration, optical registration of dual channel for CCD and EMCCD is achieved by the high magnification optical registration system. System integration、optical registration and accuracy of optical registration scheme for spaceborne low light remote sensing camera with short focal depth and wide field of view is proposed in this paper. It also includes analysis of parallel misalignment of CCD and accuracy of optical registration. Actual registration results show that imaging clearly, MTF and accuracy of optical registration meet requirements, it provide important guarantee to get high quality image data in orbit.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.