Abstract: An optical member includes a fused silica glass having a concentration of ≡SiH moiety below detection limit as measured by Raman spectroscopy and a concentration of molecular hydrogen of at least 1×1017 molecules/cm3. The fused silica glass exhibits an induced absorption level which quickly attains an initial peak upon exposure to irradiation and rapidly decays to a low value. The induced absorption level after decaying to the low value remains substantially unchanged by further irradiation.

Abstract: A method for preparing high-purity, bulk fused silica includes supplying silane gas, a gaseous fuel, and oxygen gas to a combustion burner. Silica particles are formed by passing the silane gas into a flame formed by the combustion reaction of the gaseous fuel with the oxygen gas while maintaining the ratio of the flow rate of the gaseous fuel to the flow rate of the silane gas no less than twelve and the ratio of the flow rate of the gaseous fuel to the flow rate of the oxygen gas no less than three. The silica particles formed are immediately deposited onto a hot bait to form a boule.

Abstract: In furnaces for producing high purity fused silica glass boules, glass particles have a tendency to build-up adjacent the burner hole rim. It was discovered that unburned furnace gases containing silica particles where re-circulated in the furnace close to the burner hole rim and reacted with the oxygen of infiltrated air adjacent the burner hole, and thus deposited such particles in the form of a glassy build-up about the rim of the burner hole. In order to eliminate the source of oxygen adjacent the burner hole rim, a curtain of an inert gas is caused to flow through the burner hole between the sidewalls of the burner hole and the flame of the burner. Accordingly, the curtain of inert gas inhibits the combustion of the unburned hydrogen and carbon monoxide furnace gases adjacent the exit rim of the burner hole and thereby minimizes glass build-up about the burner hole rim.

Abstract: This invention relates to the production of high purity fused silica glass through oxidation and/or flame hydrolysis of a halide-free, organosilicon-R compound in vapor form having the following properties:(a) producing a gas stream of a halide-free silicon-containing compound in vapor form capable of being converted through thermal decomposition with oxidation or flame hydrolysis to SiO.sub.2 ;(b) passing said gas stream into the flame of a combustion burner to form amorphous particles of fused SiO.sub.2 ;(c) depositing said amorphous particles onto a support; and(d) either essentially simultaneously with said deposition or subsequently thereto consolidating said deposit of amorphous particles into a virtually nonporous body; the improvement comprising utilizing a halide-free, organosilicon-R compound in vapor form having the following properties:(1) a Si--R bond dissociation energy that is no higher than the dissociation energy of the Si--O bond;(2) a boiling point no higher than 350.degree. C.

Abstract: This invention relates to the production of high purity fused silica glass through oxidation or flame hydrolysis of a vaporizable silicon-containing compound. More particularly, this invention is directed to the use of vaporizable, halide-free compounds in said production. In the preferred practice, a polymethylsiloxane comprises said vaporizable, halide-free compound.

Abstract: This invention relates to the production of high purity fused silica glass through oxidation or flame hydrolysis of a vaporizable silicon-containing compound. More particularly, this invention is directed to the use of vaporizable, halide-free compounds in said production. In the preferred practice, a polymethylsiloxane comprises said vaporizable, halide-free compound.