Abstract:
The light intensity ratio adjustment filter is placed between the reference surface and the sample surface of the interferometer. This light intensity ratio adjustment filter has a light intensity ratio adjustment film including an optical reflection-absorption layer and a dielectric anti-reflection layer on the surface of a transparent substrate made of glass on the sample side, and an optical anti-reflection film on the reference surface side, and acts so as to reflect part of the incident light from the surface opposite the reference surface, and after absorbing part of the remaining light, transmit the remainder towards the sample, and furthermore, absorb part of the light returned from the sample while controlling reflection, and transmit the remainder in the direction of the reference surface as the sample light.
Abstract:
A Fourier Transform Spectrometer (“FTS”) system includes a Fizeau FTS having a plurality of sub-collecting elements, adjacent ones of which are separated by a gap distance, and at least one of which has an adjustable optical path. The FTS system further includes a Michelson FTS having an adjustable optical path. The FTS system further includes one or more processors configured to select spectral data collected by the Fizeau FTS corresponding to spatial frequencies for which the Fizeau FTS has a modulation transfer function (“MTF”) value above a first threshold level, to select spectral data collected by the Michelson FTS corresponding to spatial frequencies for which the Michelson FTS has a MTF value above a second threshold level, and to combine the selected spectral data from the Fizeau FTS with the selected spectral data from the Michelson FTS.
Abstract:
Heterodyne spectrally controlled interferometry is performed by combining a delay line in Twyman-Green configuration with a Fizeau interferometer. By splitting a white-light beam in the delay line and introducing a time delay in one of the resulting beams, the delay line produces a recombined output beam with a sinusoidally modulated spectrum. By introducing a frequency shift in one of the beams in the delay line, the output beam is also continuously phase shifted in the spectral domain in a time-varying fashion, as required for heterodyne SCI.