METHODS AND DEVICES FOR ADDING POLARIZATION SENSING FUNCTION TO STANDARD LOW COHERENCE INTERFEROMETRY

摘要

The present invention describes a scheme of reconfiguring an ordinary OCT system to a PS-OCT variant. In this scheme, a polarization mode-dependent optical delay (PMOD) unit is inserted at the sample arm of the OCT interferometer. As a consequence of its large retardation, the resulted OCT image contains a plurality of image replicas separated by the group delay difference of the polarization modes. The polarization-sensitive interference can be analyzed by the amplitude ratios between the replicated images. Because of the simplicity of this method, an ordinary OCT system can be easily and cost-effectively reconfigured to add a useful PS-OCT imaging function. This method can be applied to any low coherence interferometric technique such as spectral-domain OCT, time-domain OCT, and spectral-encoded microscopy.