Low power PECVD SIC delay lines for optical coherence tomography in the visible

The scanning delay line is a key component of time-domain optical coherence tomography systems. It has evolved since its inception towards higher scan rates and simpler implementation. However, existing approaches still suffer from drawbacks in terms of size, cost and complexity, and are therefore not suitable for implementation using integrated optics. In this paper we report a rapid scanning delay line based on the thermo-optic effect of amorphous silicon carbide for application in the visible. The reported device attained line scan rates of 50 Hz and demonstrated a scan range of 0.4 mm. The devices use 40 times less power than similar architectures based on silicon.