Based On The Diffraction Optical Element Wide-field Optical Receiving Antenna Study

The wide field of view optical receiving antenna has many important applications in areas such as space optical communication. Currently, the viewing angle division is generally used in optical receiving antenna of wide viewing angle, using more detectors or complex access system (such as fiber array), but it is mainly used for the orientation detection in optoelectronic countermeasures, not suitable for laser communication. In the applications of space optical communication, the antenna systems usually scan airspace with a beam of light, such as using two-dimensional or three-dimensional universal frame type mechanical APT (acquisition, pointing, tracking) optical antenna system, which is mainly controlled and rotated by the electrical and mechanical equipment. But there are some problems exiting in ATP systems, including the slow response, poor real time and the alignment accuracy affected by the mechanical vibrations.This paper is mainly focus on the indicators for the wide field of view and large-caliber reception area, using a small receiving area of photodetectors of antenna as a constraint premise, thus a wide field of view receiving antenna has been designed, which has fast response, good real time performance, and don’t need to track and point accurately. Regarding these mentioned above, using the idea of diffractive optical elements, a new optical antenna structure has been designed in this paper, by adding a special designed diffractive optical element to the focal plane of an ordinary large-diameter lens in the optical antenna, which enables the focused incident beam to be a parallel beam or concentric beam by diffraction, and then through a short focal length lens focused to the photodetector, resulting in the wide field of large aperture optical receiving antenna. This paper proposes a transmission and reflection type holographic recording program for diffractive optical element as well as the description of principles and modeling analysis. The experiments have recorded and tested the single point type of diffractive elements, and the focused laser beam in diffractive elements input by the parallel beam in different angles has obtained good diffraction effects. Thus it is clear that the diffraction elements have a better angle redundancy. The paper also proposes to use a ground glass or a microlens array as the overall record of diffraction components, and fulfill the overall records of diffractive elements input by the ground glass, thus verify the reproduction effect through experimenting.