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:
Sep. 26, 2000
Filed:
Oct. 19, 1998
NHK Spring Co., Ltd., Yokohama, JP;
Abstract
An optical waveguide device is provided with a core formed on a substrate and a clad layer. A low-temperature film-forming method, such as the CVD or PVD method, is used in a core forming process for forming the core and a clad forming process for forming the clad layer. The surface of the clad layer is coated with a protective film of chrome or the like in a protective film forming process that is carried out after the clad forming process. In a heating/pressurizing process that is carried out after the protective film forming process, the clad layer is heated and pressurized from its outside by the HIP (hot isostatic pressing) method. This heating/pressurizing process substantially eliminates voids in the clad layer and the like, and enhances or improves the density of a buffer layer, core, and upper clad layer and the transparency of the core layer. The protective film is removed by etching or the like in a removing process.