Simplified method for polarization-sensitive optical coherence tomography

We report a method for extracting the birefringence properties of biologica l samples with micrometer-scale resolution in three dimensions, using a new form of polarization-sensitive optical coherence tomography. The method me asures net retardance, net fast axis, and total reflectivity as a function of depth into the sample. Polarization sensing is accomplished by illuminat ion of the sample with at least three separate polarization states during c onsecutive acquisitions of the same pixel, A scan, or B scan. The method ca n be implemented by use of non-polarization-maintaining fiber and a single detector. In a calibration test of the system, net retardance was measured with an average error of 7.5 degrees (standard deviation 2.2 degrees) over the retardance range 0 degrees to 180 degrees, and a fast axis with average error of 4.8 degrees over the range 0 degrees to 180 degrees. (C) 2001 Opt ical Society of America.