Apparatus and method for data reproduction

Application Number: 00106951
Application Date: 2000.04.20
Publication Number: 1271162
Publication Date: 2000.10.25
Priority Information: 1999/4/20 JP 112840/99
International: G11B11/10
Applicant(s) Name: Sony Corp.
Inventor(s) Name: Yoshimura Toshiji;Fukumoto Atsushi;Kai Shinichi
Patent Agency Code: 31100
Patent Agent: hong ling
Abstract A DWDD type data reproducing apparatus which handles a magneto-optical recording medium having a magnetic three-layer film consisting at least of a displacement layer, a switching layer and a memory layer. A reproduced signal is first equalized with regard to its waveform and then a detection signal representing generation of a magnetic wall displacement is produced by using a differential signal or a secondary differential signal of the reproduced signal without being harmfully affected by any sudden DC level variation caused in the reproduced signal. Subsequently a data detection circuit detects the data by the use of such detection signal and then outputs the reproduced data. In this apparatus, the data can be reproduced at a sufficiently low bit error rate despite occurrence of any sudden DC level variation caused in the reproduced signal.