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. 31, 1991
Filed:
Nov. 06, 1990
Hiroyuki Hayami, Itami, JP;
Atsushi Utsumi, Kawanishi, JP;
Dainichi-Nippon Cables, Ltd., Amagasaki, JP;
Abstract
A method for producing an optical multiple fiber unit wherein a multiplicity of optical fibers are fused together with each other and each optical fiber has a core made of pure silica glass and a cladding layer made of silica glass containing a dopant and disposed on the core, by bundling a multiplicity of preforms corresponding to the optical fibers and drawing the bundle at a high temperture using the optical fiber preforms, preforms having a three-layer construction wherein a support layer made of a silica glass having a drawable temperture of at least 1,800.degree. C. is further disposed on the cladding layer, and drawing the bundle of the preforms to give a multiple fiber wherein the support layer of each optical fiber has a thickness of 0.01 to 1 .mu.m, in order to produce a multiple fiber in which the cladding layer of each optical fiber has a sufficient thickness to fulfill the function as a cladding layer and which has an excellent image-transmitting capacity.