Correcting Optical-Axis Calculation in Polarization-Sensitive Optical Coherence Tomography

Polarization-sensitive optical coherence tomography (PSOCT) has found many applications in imaging birefringence tissue samples. Polarization-sensitive detection is often implemented by utilizing a circularly polarized incident light and detecting the two orthogonal horizontal- and vertical-polarized interference components. However, the obtained optical axes images were inappropriately represented as depth-dependent periodic maps in all reported studies. A detailed analysis confirmed that this misrepresentation was caused by the accumulation of optical retardation with depth. A simple method was proposed to numerically correct this optical-axis calculation. Experimental studies in tendon tissue demonstrated that this method can be applied to map the 2-D optical-axis distributions in enface PSOCT images.