Automatic control of moving mirror based on phase detection in FTIR spectrometer

This paper did a research on the uniform motion of the moving mirror in the spectrometer and the alignment with the fixed mirror. Firstly, a brief analysis is made on the factors that affect the uniform motion and the reasons of the misalignment. And then, a strategy is described to control the movement of the moving mirror that based on phase detection. Meanwhile, a detailed introduction to the strategy is presented from the aspects of the hardware design and algorithm realization. The experimental data and result shows the control system for the moving mirror has sufficient precision and timing to ensure the alignment needed by the interferometer in the FTIR spectrometer and the requirement by the moving mirror of its uniform motion as well. As one of the key techniques in the project of "Research and Development on the Fourier Transform Infrared and Laser Raman Spectrometer", one topic of the National 10th Five-year Program of Science and Technology, it will make a significant meaning in the area of precise driving and positioning, fast tracing and adjustment as well as feedback control, whether in theory or practicality.