OPTISCHE ABTASTVORRICHTUNG

摘要

On an optical data substrate which represents a combination of an optical and a magneto-optical data substrate, data are recorded on top of each other both by means of both pits and in a magnetic layer. A suitable optical scanning device makes it possible to read simultaneously the data stored both by means of the pits and in the magnetic layer using a ligh beam. In order to suppress the crosstalk between the data signal (PS) obtained from the pits and the data signal (MS) obtained from the magnetic layer, an electro-optical modulator (EOM) periodically tips, parallel and vertical to the track direction, the electric vector (EV) of the light focussed on the data substrate (CD) at a substantially higher frequency than that of the data signal. At the output of a differential amplifier (DV) which generates the magneto-optical signal (MS) there is a low-pass (TP) for filtering out the rotation frequency of the electric vector (EV) from the magneto-optical data signal (MS). Application in magneto-optical recording and reproduction devices.