Optical design of miniaturized laser communication receiving telescope with long exit pupil distance

In order to reduce the volume and energy consumption of the laser communication terminal, and to ensure the aperture and magnification, an improved Dall-Kirkham receiving telescope was designed according to the Gaussian optics and Seidel aberration theory of catadioptric telescopes. The lens consisted of two mirrors and five lenses, the wavelengths of the received signal light were 974 nm and 1 550 nm, the aperture diameter was 60 mm, the relative aperture was 1/3.38, the exit pupil distance was 50 mm, the field of view angle was 6 mrad, the total length was 111.04 mm, and the working temperature was 20 ℃±10 ℃. The wave aberration of the optimized lens in the 0.5 mrad field of view was better than (l/40) λ, and that in the 6 mrad field of view was better than (l/20) λ, with the energy was concentrated. In order to realize the athermalization design, the selection and design of structural materials were given, and the wave aberration of optical system under ±10 ℃ was analyzed. The results show that the lens imaging quality is good and meets the application requirements.