Deeply-Etched Optical MEMS Tunable Filter for Swept Laser Source Applications

In this letter, we report a wide tuning range MEMS-based swept laser source using deep reactive ion etching on an SoI substrate. A MEMS Fabry-Pérot filter with a free-spectral range and a tuning range wider than 94 nm is presented. The measured transmission loss of the filter is between -10.2 and -13.6 dB. This filter is used to construct a swept laser source with 85 nm tuning range. These results represent the widest tuning range reported in literature for an in-plane SoI-MEMS based swept laser source using deeply-etched free-standing distributed-Bragg-reflection mirrors. The recorded tuning range enables the use of the in-plane MEMS filter in optical coherence tomography applications.