Optical designs for space ultraviolet telescope

Ultraviolet astronomical observations are significant for studying the early-type stars including O, B, A-type stars, white dwarfs, and central stars of planetary nebulae, which could have the strongest radiation in the ultraviolet region. Since ultraviolet astronomical observations are mainly carried out in space, this paper proposed several compact, light-weight and large-field ultraviolet astronomical optical systems for space observations, including refractive optical systems, catadioptric optical systems, off-axis three-mirror systems, and coaxial four-mirror systems. Combined with the optical designs, we discussed the characteristics of the designed systems, and the possibility for infrared observation by all reflective optics. In the paper, we introduced four compact optical designs: the 100mm aperture F/2.5 refractive system with 12 degrees field of views, the 100mm aperture F/2.5 catadioptric system with 10 degrees field of view, the 100mm aperture F/3 off-axis three-mirror system with 10 degrees field of view, the 100mm aperture F/2 coaxial four-mirror system with 6 degrees field of view. Optical performances and space adaptability of these designed telescopes are analyzed and compared in this paper.