High-speed path length scanning using a Herriott cell delay line

Summary form only given. Optical coherence tomography (OCT) has been extensively investigated as a diagnostic tool in a variety of medical fields, demonstrating its feasibility as a high speed, non-invasive, high resolution in vivo and in situ imaging modality. Typical OCT systems require a mechanically translating reference arm mirror to achieve axial scanning. Scan velocities for galvonometer based scanning systems are limited by mechanical inertia to approximately 3 cm/s with repetition rates of /spl sim/100 Hz. In order to remove motion artifact for imaging in vivo, image acquisition rates of several frames per second are necessary. We demonstrate a simple, low cost, alternative scanning delay line capable of scanning over several millimeters at 2 kHz repetition frequency. The system uses a multi-pass mirror geometry based on a Herriott type cell, which accumulates differential delays in each pass.