MEMS-based 3D confocal scanning microendoscope using MEMS scanners for both lateral and axial scan

• A new MEMS-based 3D confocal scanning microendoscope has been designed, constructed and experimentally verified.
• The compact fiber-optic endoscopic probe integrates the MEMS scanners, fiber and high-quality micro-optics.
• Both lateral scan and axial scan are performed by MEMS devices with large scan ranges and low drive voltages.
• Polarization sensitive components have been employed to suppress unwanted reflections.
• 2D and 3D confocal reflectance images of various samples have been obtained with high resolutions.

A fiber-optic 3D confocal scanning microendoscope employing MEMS scanners for both lateral and axial scan was designed and constructed. The MEMS 3D scan engine achieved a lateral scan range of over ±26° with a 2D MEMS scanning micromirror and a depth scan of over 400 μm with a 1D MEMS tunable microlens. The lateral resolution and axial resolution of this system were experimentally measured as 1.0 μm and 7.0 μm, respectively. 2D and 3D confocal reflectance images of micro-patterns, micro-particles, onion skins and acute rat brain tissue were obtained by this MEMS-based 3D confocal scanning microendoscope.