Yasuaki Maeda

11 Gbit/in/sup 2/-magneto-optical recording using a CAD-MSR disk and a blue laser diode

We demonstrated that our new structured centre aperture detection magnetically induced super-resolution (CAD-MSR) optical disk is suitable for blue laser diode (BLD) compatability. We confirmed 11 Gbit/in/sup 2/ is practicable through the margin evaluations. This recording density is equivalent to 15 GB/120mm-diameter disks. Further improvement of our CAD-MSR disk is possible, so higher recording density can be expected.

10 Gb/in. 2 MO disk using blue laser

We studied a high areal density recording using a conventional disk on a blue MO system. To increase the areal density, we used mainly three techniques. First, we reduced a disk noise by UV irradiation. Second, we made CNR higher by adjusting the thickness of a metal layer to control the thermal conductivity. Third, we adopted an optical phase shift method for land and groove recording to increase the track density. Using these techniques on an optical pick-up with a 407 nm-Kr laser and a 0.6-NA objective lens, practical system margins were obtained at a 10 Gbit/inch2 areal density.