Design of Self-Compensating Interferometer Based on Pendulum Movable Mirror

The Fourier transform infrared spectrometer (FTIR) is difficult to achieve good results in industrial field applications due to the limitations of its own volume, weight, and shock resistance. On the basis of fully utilizing the respective optical characteristics of the cube-corner mirror and the planar mirror, a self-compensating double-pendulum interferometer was designed to solve the problem of the stability of the interferometer. Through the electrical analysis and modeling of the scanning mechanism, the relationship between the controller and the scanning speed was established, and the corresponding control algorithm was realized by using high-speed digital signal processing (DSP) technology, which can control the speed error in the range of ±0.2%. The test of the instrument performance and the test of the standard sample showed that the instrument has a high signal-to-noise ratio and stability, which can meet the needs of industrial applications.