Patent ID: 8261578
Filing Date: 2012-09-11
Classification: C03B,C03C,Y10T

Abstract:
1. A fused silica article, the fused silica article having a hydrogen concentration in a range from about 0.1×10 17 molecules/cm 3 up to about 1×10 19 molecules/cm 3 and an index homogeneity of less than about 5 ppm over an area of at least about 25 cm 2 , wherein hydrogen has been loaded into a near net shape of the fused silica article, wherein the fused silica article is one of a concave optical element, a convex optical element, and a meniscus optical element having a concave surface and a convex surface, and wherein isohydrogen contours in the fused silica article are symmetric along a use direction and the hydrogen concentration decreases from a first external surface and a second external surface opposite the first external surface along the use direction toward an interior point in the fused silica article.