Fiber-based polarization-sensitive Mueller-matrix optical coherence tomography with continuous source polarization modulation

A novel fiber-based Mueller-matrix optical coherence tomography system is demonstrated for acquiring polarization images of biological tissues in vivo. The system features a single broadband source, a rapid scanning optical delay line, and an electro-optical polarization modulator that modulates the polarization states of the source light continuously. A frame of a 200 x 1515 -pixel 2D image can be acquired in half a second. The Jones matrix of a sample is calculated from two frequency components--the A-scan carrier frequency component and the beat frequency component between the modulation frequency and the carrier frequency. For samples having negligible diattenuation, the Jones matrix can be calculated from a single measurement of either the horizontal or the vertical interference signal. The system was first validated by imaging standard polarization elements and then applied to imaging biological samples.