Protecting An Optical Surface

摘要

According to one embodiment, a method includes receiving a light beam at an anti-reflective layer of optically transmissive material. The anti-reflective layer has an outer surface disposed within a recess of a protective layer of optically transmissive material, such that the outer surface is protected by the recess and the protective layer from being contacted. The outer surface is further disposed along an optical path of an optical device disposed inwardly from the outer surface. The anti-reflective layer has an average cross-sectional thickness that is less than an average cross-sectional thickness of the protective layer. The method further includes modulating the light beam using the anti-reflective layer.