Objective lens driving device and optical disc apparatus using the same
CA 2213308 C · Owner: Hitachi Media Electronics Co. Ltd. · Inventors: Miura, Michio; Izumi, Katsuhiko; Kuroda, Naomitsu
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
It is an object to perform a thin and compact design of the objective lens driving device. In order to achieve the above object optical beam is passed through a space surrounded by a tracking coil and a focusing coil which are adjacent to each other and fixed in a holder. Further, it is another object to position the objective lens with high precision in an objective lens driving device for switching a plurality of objective lenses in accordance with the type of an optical disc. In order to achieve this object, magnetic substances which are radially extended with the sliding shaft at the center are provided in the lens holder, and the magnetic substances are located within a plane …
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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 August 18, 1997 and granted October 2, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 18, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 18, 2019.
- 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
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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.