High-integrity seal for optical elements, dichromated gelatin holographic optical elements in particular

摘要

A method and apparatus for encapsulating optical elements, particularly dichromated gelatin (DGC) holographic optical elements (HOEs), exhibits a very high degree of environmental integrity. In broad terms, the optical element is disposed between opposing plates, and a metal seal soldered to the edge(s) of the plates to seal the optical element therewithin. In the preferred embodiment, the metalization includes chrome and nickel, or alloys thereof, followed by gold or platinum. The metallization is preferably applied using a low-temperature process such as vacuum deposition or sputtering. The metal seal may be in the form of a foil or wire. One or both of the plates are compatible with wavelengths of interest, and the technique may be used in transmissive and reflective configurations.