A method of forming optical quality surfaces in optical material is described. In particular, high optical quality end face surfaces are provided in diffused channel waveguides formed on LiNbO.sub.3 crystal material, or the like. A T-shaped trench is first formed by laser ablation. The top of the "T"...http://www.google.de/patents/US5059763?utm_source=gb-gplus-sharePatent US5059763 - Formation of optical quality surfaces in optical material
