Infrared optics: Holographic and surface relief devices

The use of kinoforms in IR holographic and surface relief devices is discussed. Alpha cyanoacrylates are promising for recording volume holograms, particularly if a powerful source of short wavelength, coherent light can be found. The absorption mask method may work better than with photoresists. Polyethylene and polytetrafluoroethylene have a useful degree of transparency in the IR. Although binary level surface relief devices can be made by the photoresist master process, they are not very efficient and can be complicated to encode. Graded level surface relief devices do not involve the theoretical complexities of volume holograms nor the computational problems of binary level phase holograms. A transmissive material which can be molded so that mass replication can be carried out by the same methods as for ordinary Fresnel and other plastic lenses in the visible region is required.