A high precision phase extraction method in heterodyne interferometer based on FPGA

Abstract The high-precision phase extraction method directly determines the final measurement performance of heterodyne laser interferometer. This paper proposes a digital quadrature phase-locked (DQPL) with sub-nanometer precision based on FPGA hardware and compiled LABVIEW platform. DQPL can accurately extract difference two optical signals in validity stability have been verified by simulations experiments. experimentally obtained resolution is 0.074 nm, standard deviation Monte Carlo 0.22 nm.