OPTICAL ISOLATOR

摘要

The invention is an optical isolator. In one embodiment the optical isolator comprises two linear polarizers, one at the input of the isolator and the other at the output. Positioned between the input and the output linear polarizer is a gyrotropic medium located within a resonant cavity such as a Fabry-Perot cavity. Interposed between the linear polarizer at the input of the isolator and the resonant cavity is a first polarization conversion means for converting received plane polarized optical energy from said linear polarizer to circularly polarized optical energy and interposed between the resonant cavity and the linear polarizer at the output of the isolator is a second polarization conversion means for converting received circular polarized optical energy from said resonant cavity to plane polarized optical energy. In an embodiment, the resonant cavity comprising the gyrotropic medium becomes the filtering medium to block reflected optical radiation.