The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 22, 2003
Filed:
Nov. 10, 2000
Bruno Uebbing, Alzenhau, DE;
Jan Vydra, Hanau, DE;
Heraeus Quarzglas GmbH & Co. KG, Hanau, DE;
Abstract
The invention concerns a quartz glass body for an optical component for the transmission of UV radiation with a wavelength of 250 nm and less, especially for a wavelength of 157 nm, as well as a process for the manufacture of the quartz glass body where fine quartz glass particles are formed by flame hydrolysis of a silicon compound, deposited and vitrified. Suitability of a quartz glass as represented by high base transmission and radiation resistance depends on structural properties caused by local stoichiometric deviations, and on the chemical composition. The quartz glass body according to the inventions is distinguished by a uniform base transmission (relative change of base transmission ≦1%) in the wavelength range from 155 nm to 250 nm (radiation penetration depth of 10 mm) of at least 80%, a low OH content (less than 10 ppm by weight) and a glass structure substantially free from oxygen defect centers. A quartz glass body of this kind is manufactured by a process which allows bulk embedding of hydrogen or oxygen into the glass network in that at least a two stage heat treatment takes place at temperatures ranging from 850° C. to 1600° C. before the vitrification, the last stage comprising sintering at a temperature between 1300° C. and 1600° C. in an atmosphere containing hydrogen or oxygen, or a nonflammable mixture of these substances.