Electrothermally actuated MEMS scanning micromirrors and their applications in endoscopic optical coherence tomography imaging

This chapter is focused on introducing a unique class of electrothermal bimorph MEMS mirrors and their applications in endoscopic OCT imaging. The novel bimorph actuator designs provide the electrothermal MEMS mirrors with unrivaled combination of large linear scan range, small drive voltage, and high fill factor, making them especially suitable for endoscopic in vivo imaging of internal organs. Using the electrothermal MEMS mirror-based OCT probes, clinical imaging experiments have been performed to detect and stage early bladder cancer and oral cancer. Those MEMS OCT probes have also been successfully applied to brain tissue imaging, tooth imaging, and meniscus imaging. All these imaging experiments have demonstrated the potential and feasibility of the electrothermal MEMS-based OCT endoscopic imaging. With further improvement of the robustness of the MEMS mirrors, the clinical use of this technology is coming in the foreseeable future.