Backlit digitizer tablet
CA 2050308 A1 · Owner: Siefer, David A. · Inventors: Purcell, Alexander M.; Siefer, David A.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A backlit digitizer table (10) providing uniform illumination of the working surface (24), comprising biaxial fluorescent lamps (20) supplying wide-area light emission under a sandwich top construction including an apertured shield electrode (35), a first clear spacer (40) an electrode array, (45), a second clear spacer (50) and a translucent top (55), with optically transparent supports (60) for the top.
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 June 22, 1990. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended June 22, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 22, 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.