Design of Ultra-lightweight SIC Scanning Mirror Assembly

Back structure of the ultra-lightweight scanning Mirror

The mirror body was made of silicon carbide and the supporting structure was made of indium steel. The support stiffness and surface accuracy of the scanning mirror assembly are simulated and analyzed by finite element analysis and verified by actual testing.

Finite element model of the scanning mirror assembly

The results show that the maximum root mean square (RMS) value of the scanning mirror shape error is 9.705nm, the actual test result 10.125nm, the error is 4% and meets the requirement that the RMS value should be less than 12.6nm in the case of gravity in all directions and the torque of the shaft-driven.

Surface accuracy test result

The first-order natural frequency of the component was 302.25Hz, which met the stiffness requirements. The results show that the proposed method is reasonable and effective, which solves the problem that the ultra-lightweight structure and the structural stiffness and optical surface accuracy are difficult to guarantee at one time.

Scan mirror assembly

Based on the principle of cone-sleeve and flexible hinge, a scanning mirror assembly with integrated back support is proposed. The main parameters of the flexible link are determined through numerical simulation and iterative calculation, which provides technical reference for parameter optimization of the flexible support structure.