Polarization sensitive OCT system using single mode fiber

Polarization sensitive optical coherence tomography (PS-OCT) takes into account the vector nature of light waves (state of polarization). The most complete information about the polarization properties of a biological target is given by depth resolved Mueller matrix elements. However, the construction of a Mueller matrix PS-OCT easy to use for in-vivo imaging is a difficult task. We designed and assembled a simpler and more versatile system that provides only essential depth-resolved information about the tissue polarization properties (linear birefringence retardation). The interferometer is a hybrid configuration of bulk optic and single mode (SM) optical fiber components. No polarization maintaining (PM) fiber is used. The reference and sample beams interfere in two single mode fiber couplers. The system can display either a pair of OCT images corresponding to linear orthogonal polarization components or a pair of images consisting of a polarization insensitive (pure reflectivity) image and a linear birefringence retardation map. All images are 8 bit grayscale and are acquired by fast en face scanning (T-scan) at 2 frames/s. We demonstrate in vivo en face images of the optic nerve region and the peripheral cornea.