Device for recording an audio and a video signal
CA 2005334 A1 · Owner: N.V. Philips' Gloeilampenfabrieken · Inventors: Jansen, Theodorus Henricus Petrus Gerardus
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Device for recording an audio and a video signal. In tracks (S1 S2, ... ) which are inclined relative, to the longitudinal direction of a magnetic record carrier (1) a first signal, for example a frequency-modulated audio signal is recorded in, a first layer (L1) deep in the record carrier a second signal, for, example a PCM-modulated audio signal is recorded in a second layer, (L3) which is situated less deep in the record carrier and a video, signal is recorded in a layer (L2) which is situated even less deep in the record carrier (Fig. 1). Since the PCM audio signal is subjected to an additional modulation step before it is recorded to convert it into a, QPSK (quadrature-phase-shift …
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 December 13, 1989. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended December 13, 2009.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 13, 2011.
- 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.