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Expired Canadian patentCanada

System and method for accessing tracks for optical disc apparatus

CA 1315879 C · Owner: Okawa, Sumihiro · Inventors: Okawa, Sumihiro; Wachi, Shigeaki

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Abstract From the Canadian patent

A system and method for accessing tracks for an optical disc apparatus are disclosed in which when a light spot is jumped toward a target track an, acceleration pulse is applies across a fine tracking actuator to accelerate the fine tracking actuator for a predetermined period of time, a relative speed of the light spot to the tracks of the optical disc is detected though a detection of a period of a traverse signal outputted due to a movement of the fine tracking actuator, and a control signal corresponding to the relative speed is used to control the movement speed of the fine tracking actuator. Therefore, before the end of a track jump, a constant relative speed can be achieved such that …

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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 April 6, 1993. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended April 6, 2010.
  • We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledNovember 18, 1988
GrantedApril 6, 1993
Term endedApril 6, 2010
Patent numberCA 1315879 C
Classification (IPC)G11B7/08 +1 more

Timeline

Timeline From CIPO dates

19891992199519982001200420072010Application filedNov 18, 1988Patent grantedApril 6, 1993Term endedApril 6, 2010

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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.