A high retardation-amplitude photoelastic modulator study for an ultra-high speed infrared spectroscopy remote sensing measurement system

Abstract

The currently allowable photoelastic modulator based Fourier transform spectrometer (PEM-FTS) retardation-amplitude is low, and spectral resolution is relatively poor. This paper presents a method for high retardation-amplitude whose PEM is based on microtrapezoidal photoelastic crystals and Herriott-PEM. The retardation-amplitude of the improved PEM is about 19 times larger than an ordinary PEM. The ultra-high speed infrared spectroscopy remote measurement prototype is designed based on high retardation-amplitude PEM. The best spectral resolution of the prototype is 4 cm −1 , and the zero-crossing single sided interferogram scanning time is less than 5 µs.