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:
Mar. 04, 2008
Filed:
May. 24, 2006
Tadayuki Imai, Kanagawa, JP;
Kazuo Fujiura, Kanagawa, JP;
Makoto Shimokozono, Kanagawa, JP;
Seiji Toyoda, Kanagawa, JP;
Masahiro Sasaura, Kanagawa, JP;
Tohru Matsuura, Kanagawa, JP;
Tadayuki Imai, Kanagawa, JP;
Kazuo Fujiura, Kanagawa, JP;
Makoto Shimokozono, Kanagawa, JP;
Seiji Toyoda, Kanagawa, JP;
Masahiro Sasaura, Kanagawa, JP;
Tohru Matsuura, Kanagawa, JP;
Nippon Telegraph and Telephone Corporation, Tokyo, JP;
Abstract
The invention provides an optical waveguide material whose refractive index can be tailored without changing the ratio of Ta and Nb. An optical waveguide of this invention comprising an under-clad layerand a corethat is formed on the under-clad layerand has a higher refractive index than that of the under-clad layeris shown. For example, KTN (KTaNbO) is used as the core, and a material that is obtained by substituting at least one element selected from the group consisting of Zr, Hf, and Sn for a portion of one element of the constituent elements of KTN and has the same perovskite type crystal structure as KTN is used as the clad. The refractive index of KTN can be reduced considerably, and this controllability widens the degree of freedom in the design of optical waveguide devices.