Measurement of Thickness and Refractive Index of Optical Samples in FD-OCT with Two Orthogonal Polarized Lights

This chapter proposed an improved structure of frequency-domain optical coherence tomography (FD-OCT) which can measure the thickness and the refractive index of unknown sample simultaneously. In the conventional FD-OCT system, the mirror signal and autocorrelation terms will be generated after the inverse Fourier Transform and result in measurement range is restricted. Therefore, this study presents an improved method using the theory of phase-shifting algorithm with two orthogonal polarized lights to increase measurement range and eliminate unnecessary noise. By phase-shifting algorithms, eliminating unnecessary noise becomes possible and the measurement range is doubled. In other words, the structure of FD-OCT achieves simultaneous measurement of thickness and refractive index of optical samples based on full-range measurement.