REFRACTIVE-INDEX PATTERNING OF TELLURITE GLASS SURFACES BY LASER SPOTHEATING

A dot pattern of a refractive-index change was formed by spot heating with laser-beam irradiation on sodium tellurite glasses. The 15Na(2)O . 85TeO(2) (mol.%) glass doped with 2 mol. % of CoO was irradiated by a green light-beam spot (532 nm) similar to 800 mu m in diameter from the second-harmonic generator of a Q-switched pulsed YAG laser, The ma p of the refractive index of the glass was determined with an He-Ne la ser beam by a scanning ellipsometric technique at a resolution of 100 mu m X 50 mu m, indicating that the spots possessing a refractive inde x lower by similar to 0.05 were formed at the region irradiated by the laser beam. (C) 1998 Optical Society of America.