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. 25, 2001
Filed:
Jul. 29, 1999
Michael Fokine, Bandhagen, SE;
Telefonaktiebolaget LM Ericsson, Stockholm, SE;
Abstract
In order to produce a periodically varying refractive index in an optical material such as optical fiber, the concentration of a refractive index varying material, for example, fluorine, is periodically varied. A mobile substance is first diffused into the optical material. A portion of this mobile substance is periodically activated by application of periodically varying radiation supplied to the optical material having the mobile substance diffused therein. Molecular hydrogen may be used as such a mobile substance. After activation of the mobile substance, inactivated mobile substance is diffused out of the optical material, this diffusion step being accelerated by application of heat. Subsequently, the optical element is heated to a predetermined level to further react the mobile substance whit a component of the optical material which may then be diffused out of the optical material to produce a periodically varying optical property such as refractive index.