Motion detector with improved signal discrimination
CA 2135929 C · Owner: Evans, Scott T. · Inventors: Lee, Wade P.; Evans, Scott T.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An infrared motion detection device for detecting the presence of a target object including special circuitry for reducing false alarms. In particular, coupling circuitry (36 41) is interposed between signal processing circuitry (13',39,13",39") and comparator circuitry (16,16'), which serves to match the baseline level of the signal from the signal processing circuitry with the baseline level of a threshold or thresholds defined by the comparator circuitry. The coupling circuitry may be implemented in a particularly simple manner, which reduces the manufacturing cost of the circuitry and the device.
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 May 19, 1993 and granted March 4, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 19, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 19, 2015.
- 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.