Polarized low-coherence interferometer based on a matrix CCD and birefringence crystal with a two-dimensional angle

In this paper, an electronically scanned polarized low-coherence interferometer (PLCI) based on a matrix charge-coupled-device and birefringence crystal with a two-dimensional angle is proposed and demonstrated. By using a sensing interferometer composed of the fiber end face and the glass surface, the proposed system is applied to displacement measurement. The two-dimensional interference fringes are captured and comprehensive demodulated by different algorithms. The experimental results showed that, compared with a traditional PLCI system, the proposed system significantly expanded the measurement range (reach ~301 μm), and meanwhile ensured low measurement deviation (kept within ± 7 nm) and high resolution (2.52 nm).