Light induced refractive index changes in PMMA films doped with styrene

Holographic recording of Bragg gratings for wavelength division multiplexing in doped and partially polymerized poly(methyl methacrylate)

Bragg gratings are recorded in doped and partially polymerized poly(methyl methacrylate) with green light (wavelength, 532 nm) in transmission geometry, and the gratings are read in reflection geometry with infrared light (wavelength, approximately 1550 nm). Diffraction efficiencies of more than 99% with a wavelength bandwidth of approximately 1 nm are obtained for single gratings with a typical length of 15 mm. Superposition of four gratings in a volume sample has been demonstrated as well. The material is promising for use in the fabrication of add-drop filters, attenuators, switches, and multiplexers-demultiplexers for optical networks that use wavelength division multiplexing.

Dry polymer for holographic recording

A dry polymeric mixture rendered red sensitive with a dye has been used to record interference gratings and holograms. Diffraction efficiencies of ~10% can be attained with exposures of ~94 mJ/cm(2). If necessary the reading step can be done just after the exposure or after a fixing step performed with light from a mercury lamp.