Wideband visible wavelength range MEMS Fabry-Perot Tunable Filter with calibration system

We report the novel MEMS (Micro Electro Mechanical Systems) FPTF (Fabry-Perot Tunable Filter) and its calibration system that controls the wavelength of the transmission peak accurately in the wide wavelength range of visible light. The MEMS FPTF consists of the Fabry-Perot filter with Ag alloy mirrors, the electrostatic actuator and the capacitive gap sensor. The calibration system consists of the capacitive gap sensor, the capacitance measurement circuit and the voltage controller. By introducing the calibration system to MEMS FPTF, we had accomplished the wavelength accuracy less than ±1nm, which is required to the highly accurate spectrum measurement in the range from 400nm to 700nm.