S Konishi, K Shingyouchi, A Makishima - Journal of non-crystalline solids, 1988 - Elsevier
Preparation of radial gradient refractive index (r-GRIN) glass rods has been undertaken by a
sol-gel process using metal alkoxides. Two binary systems, Si (OCH 3) 4 Ge (OC 2 H 5) 4 …