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:
Aug. 30, 1977
Filed:
Aug. 24, 1976
Karlheinz Rau, Hanau, DT;
Albert Muhlich, Frankfurt, DT;
Fritz Simmat, Gelnhausen, DT;
Norbert Treber, Kriftel, DT;
Heraeus Quarzschmelze GmbH, Hanau, DT;
Abstract
There is disclosed a process for preparing a foreproduct useful in the production of an optical self-focusing lightconductor in which the index of refraction of the lightconductor diminishes with increasing distance from the conductor axis such that, when plotted against the conductor diameter, the refractive index curve is parabolic and the apex of the parabola lies over the center of the conductor diameter wherein a plurality of layers of doped silica are deposited on a cylindrical support, the layers being formed of a mixture of a vaporous silicon compound and a vaporous doping agent at elevated temperature. The invention involves depositing at least one layer of undoped silica between layers of doped silica and following each deposition of each doped or undoped silica layer by heating step in which the material is heated to a temperature of at least 900.degree. C to vitrify the same. Each layer is deposited in a thickness ranging from 0.1 to 20 .mu.m.