Liquid Crystal Fourier Transform Spectrometer

A new high throughput imaging spectrometer is described that utilizes a digitally switched polarizing interferometer to sample the complex autocorrelation of the input spectrum. Using a single filter stage and high speed digital liquid crystal switches, the spectrometer can provide rapid measurements of power spectra using a simple, easily driven, light efficient structure. The spectrometer is well suited to visible/near infrared operation, due to it's use of path-length differences in crystals, rather than free space path length differences. The spectrometer provides accurate and stable steps in path length difference from zero to hundreds of waves.