Hiroyuki Tsuchinaga

High-speed recording technologies for a magneto-optical disk system

High-speed and high-density recording on magneto-optical disks has been achieved with accurate edge control. The Highest transfer rate of 64 Mb/s is obtained.

High-speed/high-density magneto-optic recording

The highest transfer rate, 64 Mb/s, and a recording density of 0.78 micrometers 2/bit in a magneto-optic disk system have been achieved.

Consideration of Jitter on Mark-Edge Recording

Almost all optical disks have adopted a mark edge recording standard to increase the data capacity. The interchangeability of drives and media is important because an optical disk is exchangeable media. This paper focuses on a jitter characteristic that is important for estimating this interchangeability. The deviation factors of jitter are analyzed and an analysis equation of jitter regarding the probability of generating a mark and space is deduced. In addition, a method to measure the remaining-edge shift in these factors is reported.

Focusing Servo Method Using the Autofocusing Effect due to Wavelength Change of Diode Lasers

An autofocusing effect due to wavelength change of diode lasers has been investigated. The following range of an optical spot towards an optical disk widens to maximum of 35 µmp-p as the chromatic aberration of a lens increases to 2.7 µm/nm. This effect occurs at high laser power, and can be used in a focusing servo in an optical pickup to write and/or read data pits.