Spatially encoded optical coherence tomography based on a tandem interferometer

Abstract

The proposed system provides depth-resolved identification of the optical birefringence of a sample. The system is comprised of a tandem of readout and sensing interferometers with reference and sample arms without any mechanical scanning in depth. For either of the components, the readout interferometer compensates for the optical path length differences in the sensing interferometer within a given interval of depth in the sample. The spatially interfered fringe patterns are read out by using a detector array without any mechanical scanning in depth. The fringes are devoid of cross-correlation artifacts when recombining the scattered beam from the sample and the reflection beam from the reference arm with orthogonal polarizations. The system provides fast electro-optic switching over orthogonal polarization components of a light beam at the same output from the sensing interferometer. The proposed polarization sensitive optical coherence tomography system was constructed by using a single-line-scan charge-coupled devices. The axial resolution of the proposed system was measured about 8 mu m.