Self-aligned v-grooves and waveguides
CA 2093628 C · Owner: British Telecommunications Public Limited Company · Inventors: Welbourn, Anthony David
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method of forming a pair of V-grooves in alignment with an array of planar waveguides comprises the steps of simultaneously forming cores (5) for the waveguides and windows (6) for the Vgrooves (8), covering the cores with a protective layer (7) and form-, ing the V-grooves through the windows. The method is such that the V-grooves (8) are formed on each side of the array of waveguides.
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 October 2, 1991 and granted February 25, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 2, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 2, 2013.
- 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.