Method for Reading Magneto-Optical Storage Media
Original Publication Date: 1986-Sep-01
Included in the Prior Art Database: 2005-Mar-09
When their magnetization is reversed, known magneto-optical materials yield only rather small light polarization changes, thus making it difficult to obtain acceptable signal-to-noise ratios in the read signal. Fig. 1 shows an improved reading scheme, according to which a magneto-optical information bearing surface 1 (the magnetization direction being perpendicular to the surface) on an optical disk 2 is illuminated by a light beam 40 from a laser 10 through lens L1, beam splitter 41 and lens L2. Beam splitter 41 is a non-perfect polarizing beam splitter operating such that only a fraction of the beam with the intensity I1, which has been reflected at surface 1, is transmitted.