| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a fused silica glass having a refractive index homogeneity of less or equal to about 5 ppm over an aperture area of at least about 50 cm<SP>2</SP>, containing substantially no halogen and having an absorption edge of less than 160 nm. <P>SOLUTION: The glass is dried by exposing a silica soot blank to carbon monoxide before consolidation reducing the combined concentration of hydroxyl group (i.e., OH), where H is protium (<SP>1</SP><SB>1</SB>H), and deuterioxyl (OD), where D is deuterium (<SP>2</SP><SB>1</SB>H), to about less than 20 ppm by weight in one embodiment, less than 5 ppm by weight in another embodiment, and about less than 1 ppm by weight in a third embodiment. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
