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:
Dec. 10, 1991
Filed:
Mar. 01, 1989
Kazuo Fujiura, Mito, JP;
Yasutake Ohishi, Mito, JP;
Michiya Fujiki, Mito, JP;
Terutoshi Kanamori, Mito, JP;
Shiro Takahashi, Mito, JP;
Nippon Telegraph and Telephone Corporation, Tokyo, JP;
Abstract
Provided is a process for preparing a homogeneous fluoride glass containing high purity BaF.sub.2 through the CVD process characterized in that the used gaseous mixture comprising: a barium .beta.-diketonate complex serving as a first starting material and represented by the following general formula (1) of: ##STR1## wherein R is an alkyl group having 1 to 7 carbon atoms, R' is a substituted alkyl group having fluorine atoms substituting hydrogen atoms and represented by C.sub.n F.sub.2n+1 where n is an integer of from 1 to 3; a gaseous or vaporizable compound of the metallic element constituting said fluoride glass, the gaseous or vaporizable compound serving as a second starting material; and a fluorine-containing gas serving as fluorinating agent. Further provided is a process for preparing a preform for a fluoride optical fiber which is low in transmission loss, by depositing the fluoride glass over the interior wall of a cylindrical tube or the wall of rod-like glass substrate through the CVD process followed by collapsing.