Wide field of view, ultracompact static Fourier-transform spectrometer

Abstract

The development of a novel static Fourier-transform spectrometer based on two Wollaston prisms, two polarizers, and a compact two-dimensional detector array is described. The wavelength calibration is fixed by the geometry of the prisms and the detector array and is therefore inherently stable. The Wollaston prisms are fabricated from materials with opposite sign of birefringence which gives a significantly increased field of view compared with existing Wollaston prism based Fourier-transform spectrometers. The spectrometer operates in the visible region of the spectrum, has a resolution of 350 cm−1, an aperture of 6×4.6 mm, and a field of view of ±10°. The optical assembly is interfaced to a laptop computer resulting in a rugged, portable instrument with no moving parts.

Compact Liquid Crystal Based Fourier Transform Spectrometer System

“…However, due to the modal dispersion and high order mode interferences, the liquid crystal waveguide structure is only capable of operating over a wavelength of a few hundred nanometers. A static Fourier transform spectrometer utilizing two Wollaston prisms was developed by Steers et al (1997). However, the nonlinear relation between the optical path difference (OPD) and the wedge thickness make the design complicated, with limited field of view.…”