Apparatus for writing and/or reading information on a rotary information disc with the aid of a radiation beam
CA 1183257 A · Owner: N.V. Philips Gloeilampenfabrieken · Inventors: Camerik, Eduard
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
14, ABSTRACT:, By means of a radiation beam an apparatus writes or reads information on an information surface of a rotary optical information disc, which apparatus comprises an objective frame on which an objective for concentrating the radiation beam to form a radiation spot is mounted by means of a parallel guide in such a way that it can move along its optical axis. The objective is protected against dust, contaminants and mechanical damage by means of stationary plane-parallel, radiation-beam-transmissive shielding means which are interposed between the objective and the rotary information disc, the lens system of the objective being corrected for the optical properties of the …
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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
- Granted February 26, 1985. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended February 26, 2002.
- 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.