ing at the deficiency of the design of irradiance attenuators for solar simulators, we proposed a new design method of attenuators to improve their irradiance uniformity. According to the theory of Etendue, the mesh area of an attenuator was calculated and the radiation flux in the convergent optical path was modulated. Furthermore, the radiation distribution on the attenuator was theoretically analyzed by the zoned method of condenser. Then, the structure of non-uniform mesh distribution was designed to modulate the radiation distribution in the convergent optical path and the specific design parameters were provided. In addition, the effects of attenuators with uniform and non-uniform mesh distributions on radiation modulation and irradiance uniformity were compared and analyzed. The results suggest that the irradiance of 0.1--1.0 solar constant can be output continuously after an attenuator with non-uniform mesh distribution was installed and the power of xenon lamp was adjusted. Besides, after the modulation of radiation distribution, the maximum reduction rate of irradiance non-uniformity in the spots is 48.7%, and the wide adjustment of irradiance at low irradiance non-uniformity can be realized, which has certain reference significance for improving the performance of solar simulators.

ing at the wide-field-of-view and high-resolution imaging requirements of the airborne photoelectric imaging systems, we design a multi-scale wide-field-of-view and high-resolution optical imaging system based on a concentric spherical lens. The optical system includes a large-scale concentric spherical lens and a small-scale secondary camera array, and it has the advantage of compact structure. According to the spherical aberration and chromatic aberration of the concentric spherical lens, in combination with the small-scale cameras, the aberration is further corrected for the segmentation of the field of view, achieving wide-field-of-view and high-resolution imaging. Furthermore, the whole system is subjected to experiments under stress and at high and low temperatures. The experimental results show that the imaging system has good stability. Besides, the value of modulation transfer function in the full field of view is always close to the diffraction limit of the system, and the square root of the speckle radius is smaller than the pixel size of the detector, indicating good imaging effect of the system. In conclusion, the traditional airborne imaging system cannot satisfy both wide-field-of-view and high resolution at the same time, and provides a new idea for optical imaging system design.

ing at the problem of difficult adjustment of prism-grating-prism (PGP) imaging spectrometer, the method of correcting the chromatic aberration of PGP imaging spectrometer is used to ensure that the detector image plane is perpendicular to the optical axis, and a wide-band achromatic PGP system is designed in this paper. Starting from the wide-band apochromatic theory, the minimum theoretical chromatic aberration of the three glass material combinations is calculated, which provides theoretical support for the apochromatic optical design. Using the optical design software to optimize the initial structure, the results show that the secondary spectrum of the PGP system has been well corrected, and the CCD of the detector does not need to be tilted, which is more convenient for later installation and adjustment. The coverage spectrum width is 400--1000 nm, the field of view is 9.2 mm, the spatial resolution is better than 10 μm, the spectral resolution is better than 2.8 nm, and the optical transfer function is greater than 0.7, which is close to the diffraction limit, meeting imaging requirements.