Dual IR/RF windows for laser communications

摘要

Future advanced communications systems will utilize lasers which operate at 1.55μm backed up by an RF links. To the extent that such systems utilize a common aperture, dual IR/RF windows and domes will be required. The durability of such windows, with respect to rain and sand erosion damage, is an important consideration as damaged surfaces will lead to significant optical degradation for operation at 1.55μm. This requirement drives the materials choices toward more durable materials such as ALON optical ceramic, spinel and sapphire. Single layer windows, with appropriately selected thicknesses of these materials can be used for narrow RF wavebands, but are not adequate for applications requiring broadband RF transparency. To this end, multilayer windows, with durable outer layers of ALON have been developed, and built. Recent results will be presented