Abstract
A detailed theoretical study of the transmission function of birefringent filters using exact 4 × 4 matrix formalisms is presented. The Brewster-angle effect for the filters acting as intracavity wavelength selectors is also analyzed. Finally, the change in phase of the transmitted wave is calculated and the resonance condition of a cavity with a birefringent-type selector is obtained. The results are compared with those obtained from the usual Jones method.