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:
Oct. 01, 1991
Filed:
Mar. 30, 1990
Hiroshi Aoki, Kanagawa, JP;
Osamu Maruyama, Tokyo, JP;
Hoya Corporation, Tokyo, JP;
Abstract
In a method of manufacturing an optical waveguide which comprises a substrate having a first refractive index and a light-transmitting passage which is buried into the substrate and which is formed by an ionizable substance having a second refractive index greater than the first refractive index, the ionizable substance is diffused into the substrate from an overlying layer through a diffusion-suppressing layer by impressing a positive polarity of a d.c. voltage and forms a diffused region. Thereafter, the ionizable substance is partially released from the diffused region towards the overlying layer by impressing a negative polarity of the d.c. voltage. A configuration of the diffused region is thus controlled during impression of the negative polarity of the d.c. voltage and formed into the light-transmitting passage.