Frequency selective reflector
CA 2316751 C · Owner: Chandler, Charles W. · Inventors: Chandler, Charles W.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A frequency selective reflector is provided for use in an electromagnetic antenna system, wherein the frequency selective reflector reflects electromagnetic waves having two or more frequencies. The reflector includes an inner portion which has a reflective surface which will reflect at least first and second frequencies. The reflector also includes an outer portion which will reflect electromagnetic waves having the first frequency in substantially the same direction as electromagnetic waves of the first frequency reflected from the inner portion. On the other hand, the outer portion is constructed to prevent the constructive reflection of electromagnetic waves of the second frequency in …
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 August 24, 2000 and granted December 23, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 24, 2020.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 24, 2022.
- 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.