Single mode optical waveguide
CA 1294161 C · Owner: Yasu, Mitsuho · Inventors: Kawachi, Masao; Takato, Norio; Jinguji, Kaname
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
In a single mode optical waveguide having a substrate, a cladding layer formed on the substrate a core, portion embedded in the cladding layer and an elongated, member for applying a stress to the core portion or a stress relief groove for relieving a stress from the core portion in the cladding layer along the core portion. A position, shape and material of the elongated member or the groove are determined in such a way that stress-induced birefringence produced in the core portion in accordance with a difference in thermal expansion coefficient between the substrate and the single mode optical waveguide is a desired value. - 1 -
Read the whole patent
Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Granted January 14, 1992. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended January 14, 2009.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.