An electrostatic MEMS scanner with in-plane and out-of-plane two-dimensional scanning capability for confocal endoscopic in vivo imaging

We present an electrostatic MEMS scanner for a dual-axes confocal fluorescence endomicroscope to collect fluorescent images in three orthogonal planes of tissue with large field of view (FOV) at high frame rate. The scanner employs a novel lever-based dual-gimbal structure to perform coupling-free switchable XY/XZ/YZ two-dimensional (2D) beam scanning, and uses the parametric resonance excitation mechanism to produce large-amplitude motions. Test results show that the scanner can achieve large optical deflection angles, up to ±14.5° in the X-axis and up to ±10° in the Y-axes, and displacements up to 370μm in the Z-axis at atmospheric pressure, and its resonant frequencies of Z-, Y-, X-axes are near at 0.54kHz, 3.47kHz and 8.55kHz, respectively.