Large angular range carousel interferometer for spectroscopic applications

Abstract

A six-mirrored carousel interferometer has been designed. The technique utilizes Michelson interferometer configuration which consists of six mirrors and a pair of compensating glass plates. Optical path difference generated due to rotation is used to measure angle and axis of rotation. The resultant at the output port of the interferometer is optimized to reduce nonlinearity for different ranges of rotations ±5°, ±10°, ±15°, and ±20°. When glass plates are introduced maximum nonlinearity for these ranges are 5.40 × 10 -7 , 8.53 × 10 -6 , 4.18 × 10 -5 , and 1.26 × 10 -4 respectively. The reported interferometer has applications in high resolution Fourier transform spectroscopy and commercially available gas analysis systems apart from other metrological applications.