Loading patent…
AssigneeNippon Telegraph and Telephone Corporation
InventorsToru Matsuura, Shiro Nishi, Shigekuni Sasaki, Toshihiro Ichino, Fumio Yamamoto, Shinji Ando, Fusao Shimokawa, Shinji Koike
Estimating the term…
An optical waveguide which has properties including low optical losses, facile fabrication, controllable core-cladding refractive index ratio, and a high heat resistance is provided. The optical waveguide for light transmission therethrough has a core made of a polyimide obtained from at least one tetracarboxylic acid dianhydride and at least one diamine. The polyimide is (a) a polyimide homopolymer derived from a diamine represented by formula [I] as follows: ##STR1## (b) a polyimide copolymer derived from at least one diamine including the diamine represented by the formula [I]; or (c) a mixture of the polyimide homopolymers.
An optical waveguide for light transmission therethrough having a core, wherein the core is made of a polyimide obtained from at least one tetracarboxylic acid dianhydride and at least one diamine, the polyimide being selected from the group consisting of
An optical waveguide having a core for light transmission therethrough, wherein the core is made of a polyimide copolymer including at least two units represented by the formulae [II]and [III] as follows:
A method for making an optical waveguide for light transmission, the optical waveguide having a substrate and at least two stacked layers, first and second layers, formed to cover the substrate, the method comprising the steps of:
A method for making an optical waveguide for light transmission, the optical waveguide having a substrate and at least two stacked layers, first and second layers, formed to cover the substrate, the method comprising the steps of:
Dependencies are inferred from the claim text.