초록 ▼

The present invention relates to a quartz glass blank for an optical component for transmitting radiation of a wavelength of 15 nm and shorter, the blank consisting of highly pure quartz glass, doped with titanium and/or fluorine, which is distinguished by an extremely high homogeneity. The homogene

The present invention relates to a quartz glass blank for an optical component for transmitting radiation of a wavelength of 15 nm and shorter, the blank consisting of highly pure quartz glass, doped with titanium and/or fluorine, which is distinguished by an extremely high homogeneity. The homogeneity relates to the following features:a) micro-inhomogeneities caused by a local variance of the TiO2 distribution (<0.05% TiO2, averaged over a volume element of (5 μm)3 in relation to the mean value of the TiO2 content),b) an absolute maximum inhomogeneity in the thermal expansion coefficient Δα in the main functional direction (<5 ppb/K),c) a radial variance of the thermal expansion coefficient over the usable surface of the quartz glass blank of not more than 0.4 ppb/(K.cm);d) a maximum stress birefringence (SDB) at 633 nm in the main functional direction of 2 nm/cm with a specific progression; ande) a specific progression of the Δα, averaged according to (b) on the optical surface.Said quartz glass blank can only be obtained in that a doped quartz glass obtained by flame hydrolysis of a compound containing silicon, titanium and/or fluorine is formed as a large volume rod-shaped starting body into a homogeneous quartz glass blank using several forming steps and is homogenized.

대표청구항 ▼

The invention claimed is: 1. A quartz glass blank for an optical component for transmitting radiation of a wavelength of 15 nm and shorter, said blank being cylindrical and having a cylinder axis with a height, and comprising highly pure quartz glass, doped with titanium and/or fluorine, wherein sai

The invention claimed is: 1. A quartz glass blank for an optical component for transmitting radiation of a wavelength of 15 nm and shorter, said blank being cylindrical and having a cylinder axis with a height, and comprising highly pure quartz glass, doped with titanium and/or fluorine, wherein said quartz glass has:a) micro-inhomogeneities caused by a local variance of a distribution of TiO2 therein of less than 0.05% TiO2 averaged over a volume element of (5 μm)3 in relation to a mean value of a TiO2 content in the quartz glass blank;b) a thermal expansion coefficient, averaged over the height of the cylinder axis, varying over an optically used surface of the quartz glass blank with a maximum inhomogeneity of less than 5 ppb/K;c) the thermal expansion coefficient varying along the optically used surface substantially according to Δα from the formula (1):