Visual signaling apparatus
CA 2028461 C · Owner: Roberts, John K. · Inventors: Roberts, John K.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A visual signaling apparatus including an enclosure having an aperture, and defining a cavity a light source for, emitting light in predetermined wavelengths borne by the enclosure and positioned in the cavity; and a semi-transparent dichroic mirror borne by the enclosure and disposed in substantially occluding relation relative to the aperture the semi-transparent, dichroic mirror adapted to selectively reflect ambient light and transmit the predetermined wavelengths of light emitted by the light source.
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 23, 1990 and granted November 8, 1994. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 23, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 23, 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.