Mass-Producible Optical System Design and Rapid Alignment Method for Inter-Satellite Laser Communication

With the rapid development of space laser communication technology, the demand for high-speed inter-satellite networking has been growing significantly. However, existing research on inter-satellite laser communication payload is still primarily experimental, featuring complex optical system designs that require lengthy and costly processes for manufacturing, alignment, and testing—posing challenges for low-cost and rapid mass production. To address this issue, a transmissive optical antenna with single-band achromatic design is proposed in this paper, along with a rapid alignment method for measuring the magnification of the optical antenna based on a collimator. By narrowing the chromatic aberration correction range, the length of the optical antenna was reduced by 15.83%, the number of lenses was decreased from six to four, and the manufacturing cost of a single optical antenna was reduced by 33.33%. Simulation results indicate that the alignment tolerance range for magnification is 4.37 to 5.08. After actual alignment, the measured magnification is 4.82, with a beam divergence of 67.53 μrad on the transmission path and a coupling efficiency of 51.42% on the receiving path. The self-calibration spot size is within 12×12 pixels. A comparative experiment is also conducted, and the alignment time of the proposed method is within 10% of that required by the interferometer method. The alignment and test results demonstrate that the proposed method not only enables a lightweight and compact design of the optical antenna, but also significantly reduces the alignment time. Simultaneous focal alignment of signal transmission, acquisition-pointing-tracking, and self-calibration optical paths is also achieved.