Optical systems with long effective focal length and large-aperture will play more important roles in space remote sensor in the future. Coaxis optical systems have been widely adopted due to its advantages including good symmetrical characteristics, compact structure, satisfying volume and rotary inertia. But the distortion of the coaxis three-mirror-anastigmat system is often larger than one percent of the image height and past correction is hard, which is unfavourable especially for surveying and mapping camera. Based on the design ideas and aberration theoretical analysis of Coaxis reflective optics, four-mirror systems with long focal length is presented in this paper, which can achieve high image quality and ultra-low distortion .The forth reflective mirror is set near the exit pupil to correct the aberration related to the pupil, and the processing difficulty of the primary mirror is also lowered. Example of the optical design and image quality forecasting is also given at the end of the paper.
Spacing movable mechanic components are needed not only to move in wide range but also to complete series of actions with high degree of accuracy and stability when processing on orbit. So, visual monitor system including the surveillance and measuring cameras must be equipped to achieve precise spacing location and posture information, and monitor and administer of movable mechanic components can be realized combined with the algorithm. Based on the requirements of the camera and the after algorithm for the center of mass and the distribution of spot on image plane at different object distance, the design peculiarity and difficulties are analyzed, optical design examples are also given at last. The optical system adopted telecentric structure, the relative aperture is 1/3.5, field of view reaches seventy-six degrees, wavelength ranges from 500nm to 800nm, the center of mass of the spot on image plane varies non-obviously, high modulation transfer function, low distortion and high relative illumination are achieved, all of these can wholly satisfied the using demands of the surveillance and measuring camera. spacing movable mechanic components; space station; surveillance and measuring camera; telecentric; large-field; spot; distortion; illumination
OFFNER hyperspectral imager using convex grating as spectral splitting component has many merits including large relative aperture, no smile, small key stone, compact construction and easier assembly and etc, has widely used in many occasions of various fields. Design of double-band hyperspectral imager using OFFNER structure is presented in this paper. SHAFER fore telescope system and convex grating imaging are adopted, groove etching density is different in different region on the same substrate for different spectral band, and different diffractive order is used respectively to split the two spectral bands. The optical system achieves good image quality in wide spectral range, compact construction and small volume. And all the reflective curved face are sphere, moderate tolerances are good for the processing and alignment.
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