A gain coupled distributed feedback semiconductor laser
CA 2310604 A1 · Owner: Northern Telecom Limited · Inventors: Makino, Toshihiko; Hong, Jin
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A gain coupled DFB semiconductor laser with a high order grating structure is provided. By varying the order and duty cycle of the grating and shape of grooves, a predetermined ratio of gain to index coupling coefficients is obtained. Beneficially the laser includes a multiple quantum well structure with the grating etched directly through the quantum wells of the active region. Deep etching ensures strong gain coupling in the laser while usage of a high order grating reduces index coupling associated with the etching. As a result, a stable, high yield, high power and single mode operation of the DFB laser is achieved. For gratings of a particular order of diffraction duty , cycle, …
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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 November 10, 1999. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended November 10, 2019.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 10, 2021.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.