Tianyuan Gao

Reach on the measurement of the terminal performance of space laser communication system

Space laser communication system uses laser light as the information carrier to achieve intersatellite communication. And the terminal of laser communication is the key part. It is necessary to accomplish the test of performance and function, validation and judgment. The test of dynamic and static performance for terminal is the basic content and necessary steps on the reliability of space laser communication terminal. So the reach on ground test technology of space laser communication is more important. This paper mainly describes the test system of integrated performance for space laser communication terminal. The test range of system includes two essential parts, i.e, static test and dynamic test. Static test includes the angle of divergence, the coaxially of axis, communication performance and so on. Dynamic test includes the test of capture ability at dynamic and disturbance environment, and the test of dynamic track precision. The test system has achieved accurate test of dynamic track precision and multi-performances test of terminal based on simulatin at real working environment. The test result could present the anti-disturbance performance, anti-noise performance, and dynamic communication performance of the terminal.

Study on the testing device of axis parallelism

Refer to the dynamic optics theory, there is no image deflection in the rotation process of right-angle-roof prism and rhombic prism around any axis in space. That is to say, after reflection, the output optical axis from the prism is parallel to the direction of the initial optical axis. The optical character of right-angle-roof prism and rhombic prism is applied in this paper. A new testing method of multi-axis parallelism with chain of combined multi-right-angle-roof prisms or multi-rhombic prisms is proposed. And the testing error is analyzed in detail.

Study on test metrology of large aperture optical system wavefront

Large aperture optical system test has been a key problem for a long time. It could be solved by sub-aperture stitching method after the sub-apertures are tested. Sub-aperture stitching technology is a feasible method for testing large diameter optical system with small diameter interferometer sub-aperture stitching. Auto-collimating component will be needed with interferometer stitching method. Auto-collimating component is defined that the image could be kept stable when the optical component rotates about any axis in space. And the beam could be back along original optical path. By this means, auto collimation could be realized. The auto-collimating component is smaller than the test system. The whole wavefront of large aperture system could be tested through the method that the auto-collimating component moves along the guide rail and rotates about optical axis. A right angle roof prism is chosen as the auto-collimating component due to its character of easier manufacture. The active matrix, characteristic orientation and extreme axial is deduced with dynamic optics. The sub-aperture stitching testing process is simulated by ZEMAX in detail. The test result by stitching method is compared with that by directive test method for large aperture optical system. It is shown that the relative test error is less than 4.3λ 0/00. The sub -aperture stitching test method is verified.