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:
Jun. 10, 1980
Filed:
Feb. 02, 1978
Tsuneo Suganuma, Tokorozawa, JP;
Gyozo Toda, Hino, JP;
Koji Ishida, Tokyo, JP;
Shin Satoh, Iruma, JP;
Toshio Katsuyama, Kokubunji, JP;
Mamoru Sugie, Hachioji, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A method for producing an optical fiber comprises (i) the step of depositing a barrier layer on the inner wall surface of a glass tube by the CVD (chemical vapor deposition) process, said barrier layer being capable of preventing the diffusion of impurities and being made of high-silica glass which has a refractive index that is substantially equal to that of the glass tube and which contains at least one substance for lowering the refractive index of silica and at least one substance for raising the refractive index of silica, (ii) the step of depositing a glass film of desired refractive index on the barrier layer by the CVD process, (iii) the step of heating and collapsing the resultant glass tube into a composite rod or the so-called optical fiber preform, and (iv) the step of heating and drawing said optical fiber preform into the optical fiber, whereby the optical fiber which has the impurity diffusion-preventing layer between the core and the outside glass layer can be easily produced.