Time-domain Optical Coherence Tomography system with integrated delay line for surgical guidance applications

Optical Coherence Tomography is a high resolution imaging technique able to provide in-depth information about living tissue. Among all its applications, it can be argued that surgical guidance is one of the most demanding in terms of system reliability, footprint and cost. In order to enable faster adoption of this technology in that field, we had already developed and demonstrated a new type of scanning delay line based on the thermo-optic effect of silicon. By changing the temperature of an integrated waveguide, we are able to produce a variation in optical delay. In this paper, we demonstrate the inclusion of such a device in a complete system and the performance levels that can be achieved with this technique. In particular, we show a line scan rate of 2kHz with good linearity and a scan range of 0.95mm in air. These values meet the needs of most surgical guidance applications.