Tunable optical bandpass filter with high-quality vertical mirrors microassembled on movable MEMS platforms

In this paper we introduce a tunable MEMS optical bandpass filter with large vertical mirrors (450 mum tall) micro-assembled on MEMS actuators based on MEMS platform technology. The fabrication process requires only one mask, and the platform technology allows a very compact chip size with high optical quality vertical mirrors. In addition, electrostatic combdrive actuators enable precise, continuous, and independent tuning of both the center wavelength and optical passband. The 1-dB bandwidth can be continuously varied from 0.1 nm to 1.3 nm. The center wavelength can be precisely controlled over a large spectral range by either actuating the movable blocking mirrors, or by rotating the grating for coarse tuning.