Physical Characteristics and Format of a Two-Inch-Diameter Magneto-Optical Disk System with 3 GB Capacity

Autor: Takaaki Ashinuma, Eiji Ueda, Toshio Matsumoto, Eiichi Fujii, Yasushi Hozumi, Koichiro Nishikawa, Osamu Koyama, Masahiro Birukawa, Yasumori Hino, Kenzo Ishibashi
Rok vydání: 2003
Předmět:
Zdroj: Japanese Journal of Applied Physics. 42:784-791
ISSN: 1347-4065
0021-4922
DOI: 10.1143/jjap.42.784
Popis: Recording at a high density four times that of a current digital versatile disk random access memory (DVD-RAM) has been achieved by applying the domain wall displacement detection (DWDD) technology using a conventional optical head with the same wavelength of 660 nm and numerical aperture (NA) of 0.60 as those the DVD head. It has been confirmed by using an alternating sampled servo, laser annealing of the inter track area and partial response maximum likelihood (PRML) that a recording density of 15 Gbit/inch2 with a track pitch of 540 nm and bit length of 80 nm has sufficient system margins. A newly developed 1-bit-distributed address format has achieved a redundancy of 23%. Furthermore, the edge shift compensation technique has reduced the recording magnetic field. These indicate that a capacity of 3 GB on a two-inch-diameter disk is now available for mobile use. If applied to a digital video camera, one hour or more of moving-picture-experts-group-2 (MPEG2) video contents can be recorded at a bit rate of 6 Mbps.
Databáze: OpenAIRE