SYNTHETIC QUARTS GLASS FOR OPTICAL PIECE AND METHOD OF MANUFACTURING SYNTHETIC QUARTS GLASS

摘要

PROBLEM TO BE SOLVED: To provide a synthetic quarts glass having a specified large refractive index and to provide a method of manufacturing it. SOLUTION: This synthetic quarts glass for an optical piece contains carbon atom at a concentration of 50 ppm or more by substituting a part of silicon atoms into carbon atoms in a synthetic quarts glass where network structure of silica is formed. This method of manufacturing synthetic quarts glass comprises hydrolysis of a mixed gas of a silicon containing gas added by a rare earth gas and a carbon containing gas comprising either one or two or more of hydrocarbon gas, carbon dioxide gas and carbon monoxide gas. As shown in Figure, the refractive index can be adjusted by substituted carbon concentration.