Head-mounted projection display system featuring beam splitter
CA 2085735 A1 · Owner: Evans & Sutherland Computer Corp. · Inventors: Fisher, Ralph W.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A head-mounted projection display system (20) featuring a beam splitter (30) displays a simulated environment to an observer (26) using a light-weight, low cost, head-mounted projector and a retro-reflective screen (32). The display system optically colocates the projector with the observer's eyes (27) for effective use of either curved or flat retro-reflective screens. High screen gain achieved by the head-mounted projection display system (20) makes inexpensive projector sources such as a cathode ray tube (37) feasible. An alternative head-mounted display system also incorporating beam splitters producing unlimited horizontal field of view but with limited binocular overlap while …
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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 April 20, 1992. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended April 20, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 20, 2014.
- 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.