Modes of a laser resonator containing tilted birefringent plates

Optical resonators containing tilted birefringent plates as tuning devices have been studied on the assumption that the resonator modes are eigenfunctions of an assembly of retardation plates interspersed with partial polarizers. The bandwidth is narrower than that of an equivalent filter using perfect polarizers, but the extinction coefficient does not go to zero. Stacks of plates whose thicknesses are in integer ratios have bandwidths much narrower than those of equivalent Lyot filters, but the secondary maxima do not correspond to those of Lyot filters. Application to the organic-dye laser is discussed. A device analogous to the Solc filter is also considered.