Path-invariant fiber-based interferometric scanners for OCT

A path-invariant optical scanner linked with fiber-based Michelson interferometer was demonstrated for optical coherence tomography applications. The measured signal-to-noise ratio was determined to be 29.1. An orthogonal scanner implemented in the scanning interferometer was measured to have resonant frequency of 396 Hz and 36 /spl mu/m displacement under applied bias of 32 V at frequencies below resonant frequency. The system functionality was also verified based on strong correlation in bias frequency and in comb displacement between signals inputted to comb-drive and interference signals, respectively.