Lcd touch screen
CA 2038598 C · Owner: May, Gregory J. · Inventors: May, Gregory J.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A touch screen includes a liquid crystal display (LCD) having a viewing surface through which light passes into and out of the display and a back surface comprising a transflector such as transflective film. The transflector reflects some of the light beak through the display and viewing surface and transmits some of the light. An array of light dependent resistors (LDRs) or equivalent light detecting devices underlie the transflector and detect a change in the transmitted light caused by a touching of the viewing surface. The light detecting array may be integrated into a keyboard interface. Keys are then displayed on the viewing surface opposite LDRs in the array to indicate where the …
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 March 19, 1991 and granted January 8, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 19, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 19, 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.