Disclosed is a system for recording and playing back information utilizing a magneto-optical disc memory having a vertical magnetization film on and from which the information is recorded and read out by an optical means. In order to simplify the construction of the system, an optical system including...http://www.google.de/patents/US4549287?utm_source=gb-gplus-sharePatent US4549287 - System for recording and playing back information with magneto-optical disk memory using record and readout light beams of different wavelengths
