Semiconductor lasers
CA 2008379 C · Owner: Mushiage, Masato · Inventors: Mushiage, Masato; Sakiyama, Hajime; Tanaka, Haruo
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A semiconductor laser is characterized in that the first upper portion cladding layer is of double layer construction, the upper layer portion being higher in carrier concentration than the lower layer portion. As a result the series resistance component is restrained and the sequential direction voltage can be lowered without damaging the other characteristics such as the, oscillation start current.
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
- Filed January 23, 1990 and granted August 31, 1993. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended January 23, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 23, 2012.
- 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.