| 摘要 |
PURPOSE:To accurately read out data by maintaining characteristics of a large capacity, a high speed transfer rate and a high speed seek in a magneto-optical disk device, preventing deterioration of an S/N of a read signal even at the time of tracing an inner circumference and reducing an error rate of the data. CONSTITUTION:The optical information reproducing device possesses high frequency superposing circuit 7 and a split optical system capable of moving an objective 2 and a swing-up mirror 3 to other optical element containing a laser diode 5. Information is recorded and reproduced on a magneto-optical disk 1 in a zone bit recording system and also in a system for changing the revolving speed at the time of tracing a track in each block made by dividing a zone into some blocks. Then, an oscillation frequency (f) of the high frequency superposing circuit 7 is set to satisfy approximately f=c/(4Linner), where an effective optical path length from a light emitting surface of a laser diode 5 to the magneto-optical disk l at the time of tracing the innermost track of the magneto-optical disk 1 is denoted as Linner and the velocity of light as (c). |
