Three-Dimensional in VIVO Real Time Imaging by a Miniature Dual-Axes Confocal Microscope Based on a Two-Dimensional MEMS Scanner

We demonstrate a novel microelectromechanical system (MEMS) based Dual-Axes confocal (DAC) microscope in a 10-mm diameter handheld package. Miniaturization is achieved by using a barbell-shaped, gimbaled, two-dimensional (2-D) MEMS scanner that is actuated by self-aligned vertical comb actuators. The maximum DC optical scan angles are ±4.25° on the inner axis and ଑.5°g on the outer axis, and the corresponding resonance frequencies are 3.4 kHz and 1.2 kHz. The maximum imaging rate is 5 frames/second. The miniature DAC microscope operating at 785-nm-wavelength achieves full-width-half-maximum (FWHM) transverse and axial resolutions of 4.2 μm and 7 μm, respectively.