Measurement and Analysis of an Ultra-Compact Electrostatic MEMS Mirror for Lissajous Scanning Two-Photon Microscopy

The imaging performance of a Lissajous scanning two-photon microscopy system employing an ultra-compact electrostatic MEMS mirror depends critically on the stability of the scanning trajectory. However, asymmetry in driving circuit parameters and the response of the MEMS mirror introduce amplitude error and phase delay, resulting in trajectory distortion and degraded imaging performance. We establish an experimental characterization platform to evaluate the amplitude and phase responses of the driving circuit and the MEMS mirror. The frequency response of the MEMS mirror under sinusoidal excitation further reveals the phase delay between the driving signal and the mechanical motion. A two-photon microscopy imaging system is constructed to experimentally validate and correct image distortions induced by the driving circuit and response of the MEMS mirror. The research establishes a systematic framework for the realization of low-distortion Lissajous scanning in two-photon microscopy and miniaturized endoscopic imaging systems.