Optical-hybrid etalons for simultaneous phase- and polarization-diversity operations

A quarter-waveplate etalon optically irradiated on both surfaces at prescribed beam angles can function as a 90°-hybrid with balanced outputs having simultaneous phase- and polarization-diversity properties. In a similar manner for a 180°-hybrid, a conventional etalon can combine the signal polarization angle as a component to the overall phase angle in the balanced output response from the hybrid. The theoretical aspects of the hybrid etalons are developed in this paper. Experiments have also been performed to verify the theoretical models for the optical 90°- and 180°-hybrids.