Virtual Biopsies with Handheld Dual-Axis Confocal Microscope
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 ±1.5° on the outer axis, and the corresponding resonance frequencies are 3.4 and 1.2 kHz. The maximum imaging rate is 5 frames/s. The miniature DAC microscope operating at 785-nm-wavelength achieves full-width-half-maximum (FWHM) transverse and axial resolutions of 4.5 μm and 5 μm, respectively.
KeywordsConfocal microscope 2-D MEMS scanner Imaging High resolution image 3-D image
This work is partially supported from the Fraunhofer-Bessel Research Award, Alexander von Humboldt Foundation, Germany; the Newton Fund, British Council, United Kingdom; the internal research fund, the King Mongkut’s Institute of Technology Ladkrabang, Thailand; the RRI fund, Thailand Research Fund, Thailand; and the starting-up fund, National Research Council, Thailand.
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