Shinichi Kurita

2-GByte/130-mm capacity direct overwrite magneto-optical disk and drive

We have modified drives of 2Gbyte/130 mm non-DOW MO disk to be drives of 2GByte/130 mm DOW-MO disk. We have demonstrated that we have already reached the practical stage showing that it is possible to produce 2 GByte/130 mm DOW-MO disk and drive.

Optimum Recording Conditions of Direct Overwrite Magneto-Optical Disk Drive for the Widest Power Margin

The write laser power margin of magneto-optical (MO) disks is determined by, for example, the disk sensitivity and various conditions of MO drive. Especially when the multipulse writing method is used for mark edge recording, the drive conditions influence the writing power margin. The drive conditions include both the write channel conditions, such as the writing waveform and the writing power, and the read channel conditions, such as the readout equalizer. When these conditions are optimal, the drive has the widest power margin possible for the object disk. We used the multipulse writing method on direct overwrite (DOW) MO disks and examined the optimum write power condition and the optimum readout equalizer condition. As a result, the correlation between those parameters has been clarified.