Optical information recording and reproducing apparatus
April 20, 2015. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesRecord carrier having an optically readable information structure Optical recording medium and reproducing apparatus Arrangement for reading an optically readable light reflective carrier System for reproducing pulse time modulated wave forms stored along a diffractive track Optical information storage medium having grooves and pits with specific depths, respectively Optical recording medium and tracking servo circuit adapted therefor using wobbled pits Optical recording/reproducing medium and apparatus using land and groove encoded information signals and identification signals including position information Patent #: 5452284 InventorsAssigneeApplicationNo. 425902 filed on 04/20/1995US Classes:369/44.26, Servo system operation related to disc structure information format369/124.11, Of retrieved signal369/275.3Track data format/layoutExaminersPrimary: Ben, LohaAttorney, Agent or FirmForeign Patent References
International ClassG11B 007/00Foreign Application Priority Data1994-04-20 JPAbstractAn optical information recording and reproducing apparatus for recording and reproducing an information signal on/from both concave portions and convex portions of guide grooves formed on a recording medium is disclosed. The optical information recording and reproducing apparatus includes: an optical portion for focusing a light beam emitted from a light source on the recording medium; a focusing control portion for controlling a focal point of the light beam; a tracking control portion for controlling the position of the light beam; a selection portion for selecting which of the concave portions and the convex portions of the guide grooves are used for recording or reproducing; a polarity inverting portion for inverting the polarity of an output signal from the tracking control portion depending on a result selected by the selection portion; a waveform setting portion for setting a modulation pattern for the light; and a signal reproduction portion for demodulating the information signal from a light reflected or transmitted by recorded marks recorded on the recording medium; wherein at least one of the focusing control portion, the tracking control portion, the waveform setting portion and the signal reproduction portion has at least two kinds of operation conditions for recording and reproducing the information signal on/from the concave portions and the convex portions of the guide grooves, and wherein the operation conditions are selected depending on the result selected by the selection portion.Other References
Field of SearchSYSTEMS HAVING PLURAL PHYSICALLY DISTINCT INDEPENDENT TRACKS ON A SINGLE STORAGE MEDIUM SURFACERadiation beam modification of or by storage medium Light intensity adjustment or maintenance Servo signal compared to a reference signal Servo system operation related to disc structure information format Track data format/layout Pit/bubble/groove structure specifies | |
