| 摘要 |
PURPOSE:To attain the reproduction of a photomagnetic disk or a disk where the information is recorded with recesses/projections or variation of reflection factors, by rotating the polarizing direction of the reflected light separated by a half mirror by 45 deg. to obtain the separated polarization components orthogonal to each other. CONSTITUTION:When a photomagnetic disk is used to an information recording medium 5, an equal amplitude is obtained between the transmitted light and the reflected light of a polarized beam splitter 14. Thus the signal beams containing information phases are opposite to each other. Then said transmitted light and reflected light are converted into electric signals to obtain a difference between them. Thus the in-phase components are offset to each other, and the information components of phases opposite to each other are magnified double to obtain a reproduction signal having a high S/N. In the case of a disk where the information is recorded with recesses/projections or variation of reflection factors, the reflected light undergoes modulation of intensity and the information signal light made incident on the two-split and four-split detectors 15 and 18 have the same phase and an equal amplitude. Thus the highly efficient reproduction is possible by adding the output of an adder 22 of electric signals detected by the detector 15 and that of the electric signals detected by the detector 18 by an adder 24. |
