Verfahren zum Erhalt von Oberflaechen-Brechungsindexaenderungen bei einem Glaslichtleit-Bauelement

摘要

The surface index of refraction of a light-guiding glass is controllably increased or decreased by changing the alkali metal ion concentration at the surface. In one approach, these ions are replaced with similar ions of differing ionic radius. A gaseous source of replacement ions and capable of extracting the surface ions is passed over the glass surface at temperatures sufficient to permit an ion diffusion inward. Control of the process parameters permits regulating the exchanged ion layer depth and approximating a definite refractive index gradient, which is not possible with conventional cladding. Optical light guides achievable with the process are disclosed.