A Playback Experiment with the New Equalizing Method of High Density Optical Disc

Abstract

We have developed a new equalizing method for RLL (Run Length Limited) code. In this method, a frequency characteristics curve of total system H (f) is fit to consine curve that cut off frequency is equal to an optical cut off frequency. This method, combined whith 684nm laser diode and NA=0.55 objective lens, allows playback of discs that tangential density is twice of CD's.