A METHOD OF PRODUCING A PHOTOREFRACTIVE EFFECT IN OPTICAL DEVICES AND OPTICAL DEVICES FORMED BY THAT METHOD

摘要

A method for producing a refractive effect in an optical device and an optical device formed by the method are disclosed in which a material from which the device is to be formed is illuminated to induce solarisation involving a photoinitiated REDOX reaction in the material so that the material exhibits a permanent or quasi-permanent photorefractive effect. The mechanism of forming the photorefractive effect in the material relates to the photon induced oxidation of a species present in the material, either as a dopant, co-dopant or as a main component. The photo-oxidation of the species liberates an electron which, after a brief lifetime, usually finds a suitable repository by combining with some reducible species in the material. The method enables photorefractive effects to be produced in materials and, in particular, glass materials other than standard germanium-doped and silicon-based materials.