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AssigneeCanon Kabushiki Kaisha
InventorsJun SUMIOKA, Masakuni Yamamoto, Kaoru Okamoto
Estimating the term…
Provided are an optical information reproducing method capable of determining multi-level information with high precision, and an apparatus for the method. Specifically, a cell having a reduced multi-level is provided in a portion of a data region to perform the level correction or the AGC. For example, a cell recorded with an M-value for each group including a plurality of cells, each of which is recorded with an N-value (N≧3, M<N), is provided. A reproduction signal level of a cell recorded with the N-value, which follows the cell recorded with the M-value, is corrected based on a difference between a cell center value of a reproduction signal sampled when a center of a light spot is moved to a center of the cell recorded with the M-value and a reference value obtained from learning information.
A method of reproducing multi-level information recorded by changing one of a width and area of an information pit in a track direction and a phase of the information pit in virtual cells provided on a track of an optical information medium at predetermined intervals, comprising the steps of:
A method of reproducing multi-level information recorded by changing one of a width and area of an information pit in a track direction and a phase of the information pit in virtual cells provided on a track of an optical information medium at predetermined intervals, comprising the steps of:
A method of reproducing multi-level information recorded by changing one of a width and area of an information pit in a track direction and a phase of the information pit in virtual cells provided on a track of an optical information medium at predetermined intervals, comprising the steps of:
Dependencies are inferred from the claim text.