Abstract:The optical system of the H-band catadioptric star tracker is designed for application on airborne, missile, and ship-borne platforms. The total length of the catadioptric lens is 232mm, the focal length is 704.3mm, the whole field of view is 2°, the F-number is 3.9, and the detection limit magnitude is 6. The results show that the value of the modulation transfer function is close to the diffraction limit and is more significant than 0.5 at Nyquist frequency. The radial energy of each field of view is consistent, and the dispersing speckle can cover 2~3 pixels. The relative distortion is less than 0.1%, which meets the index. This paper can provide a theoretical basis and technical support for the engineering application of short wavelength infrared star trackers in near-earth space.