Laser-photodetector assemblage
CA 2014937 C · Owner: American Telephone And Telegraph Company · Inventors: Dutta, Niloy K.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Briefly, in the invention a photodetector and an injection laser are monolithically integrated on the same semiconductor chip. The laser and photodetector are positioned side-by-side and the laser mirrors can be formed bycleaving. In operation a portion of the electromagnetic energy carried in the evanescent tail of the optical mode is detected by the photodetector for monitoring the average output power of the laser. Current confinement and lateral index guiding can be provided by Fe or Ti doped semi-insulating layers of InP. The side-by-side arrangement enables the photodetector to monitor the output power of the laser without degrading the output power. - 7 -
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 April 19, 1990 and granted November 29, 1994. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 19, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 19, 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.