Regenerative mode locked laser swept source for OCT medical imaging

摘要

An optical coherence analysis system uses a laser swept source that is constrained to operate in a mode locked condition using regenerative mode-locking. This is accomplished by synchronously changing the laser cavity's net gain and/or phase based on time varying intensity of the swept optical signal generated by the laser. This produces a stable pulsation behavior, which is associated with smooth tuning (low optical frequency reference clock jitter) and low relative intensity noise (RIN).

主权项

1. An optical coherence imaging method, comprising:
providing a laser swept source to generate a swept optical signal in a laser cavity that is less than a meter long; detecting time-varying intensity of the swept optical signal; using the detected time-varying intensity of the swept optical signal as feedback to control a mode-locked operation of the laser swept source by modulating an intracavity element in the laser cavity based on the roundtrip travel time of light in the laser cavity; transmitting the swept optical signal to an interferometer having a reference arm and a sample arm, in which a sample is located; combining the swept optical signal returning from the sample arm and the reference arm to generate an interference signal; detecting the interference signal; and generating image information of the sample from the detected interference signal.