A METHOD FOR THE PREPARATION OF SYNTHETIC QUARTZ GLASS SUITABLE AS A MATERIAL OF OPTICAL FIBERS

摘要

Synthetic quartz body is prepd. by gas phase oxidative deposition of organosilane in presence of F-contg. hydrocarbon with formula CaHbFcXd; X is halogen other than F and subscripts are integers with values a = 1-3, b = 0-7, c = 1-8 and d = 0-7 such that 2a + 2 = b+c+d. SiO2 is deposited on a refractory substrate as a porous sintered body and then melted to form a transparent glass. Doped precursor rod for fibre mfr. is prepd. with addn. of at least one of GeY4, BY3 (Y= halogen or alkoxy group), PH3 or P oxychloride. Precursor for mfr. of fibre with graded index or stepped index is obtd. by deposition within quartz tube; tube is pref. heated externally to deposit SiO2 as transparent layer. Coated tube is collapsed.