High-bandwidth tilt-tip mirror with octagonal prism flexible mechanism.

Abstract

The adaptive optical system requires a tilt-tip mirror (TTM) with high bandwidth to compensate for optical beam jitter caused by atmospheric turbulence in real time. This paper introduces a novel, to the best of our knowledge, design of a voice coil TTM using an octagonal flexible mechanism and optimizes its parameters through theoretical analysis and finite element simulations. The results show that its resonance frequency in the non-working direction is up to 1005.2Hz, representing a 19.4% improvement in theoretical calculations and a 13.8% improvement in simulations compared to traditional cylindrical flexible mechanisms. Additionally, the non-working direction stiffness of the flexible support structure has been optimized, enhancing the third-order and higher resonance frequencies of the system to meet the high bandwidth requirements. A prototype of the TTM was developed based on this design, and its deflection angles and responses were measured in the laboratory, confirming the design's reliability. This low-cost, high-bandwidth TTM design facilitates miniaturization of adaptive optical systems, making it beneficial for applications in astronomical observations, laser communication, laser weapons, laser processing, and more.