LYOT DEPOLARIZER IN QUASI-MONOCHROMATIC LIGHT

An analysis is made of the depolarizing properties of the Lyot depolarizer on light of arbitrary polarization and spectral properties. It is shown that the percentage modulation of the intensity transmitted by a rotating polarizer placed behind the depolarizer is a simple function of the Fourier transform of the frequency power spectrum of the incident light. Some consequences of this behavior are examined for commonly encountered spectra, notable among which is a periodic dependence of the modulation factor on the thickness of the depolarizer when the incident beam is generated by a semiconductor laser.