An improved ternary lanthanum-zinc-borate glass composition having improved ultraviolet light transmission in near ultraviolet spectral range,... Show moreAn improved ternary lanthanum-zinc-borate glass composition having improved ultraviolet light transmission in near ultraviolet spectral range, and a process for preparing such a glass composition wherein the near ultraviolet light transmission is improved by small amounts of compounds such as lanthanum and zinc fluorides and chlorides, and tin, arsenic and antimony oxides. Sponsorship: IIT Research Institute United States Patent Show less