| 摘要 |
PURPOSE:To reduce the background noise during reproduction, by erasing the recording information obtained by the polarization of a recording medium containing a ferrodielectric layer through the polarization carried out uniformly in a single direction by a DC erasion method. CONSTITUTION:A recording medium 1 is obtained by coating a ferrodielectric layer 3 of e.g. PbTiO3, etc. on the surface of a semiconductor layer 2 of a P type silicon substrate 4, etc. A recording head 5 is shifted relatively in the direction of an arrow mark, and at the same time a digital information signal voltage 6, for example, is applied to perform recording with the polarization. On the other hand, the change of the electrostatic capacity is detected for the medium 1 through a reproducing circuit 9 while giving a relative shift to a conductive reproduction head 8 along a recording track to perform a reproduction. In the erasion mode, a conductive erasion head 21 is made to touch the surface of the layer 3 and then shifted relatively along with application of a certain level of DC voltage 22. Thus a uniform polarization is given to the layer 3 to perform erasion. In such way, the background noise can be reduced during a reproduction. |
