RECORDING AND REPRODUCING APPARATUS FOR RECORDING AND REPRODUCING INFORMATION TO AND FROM A MAGNETO-OPTICAL STORAGE MEDIUM

摘要

AN INFORMATION RECORDING/REPRODUCING APPARATUS FOR RECORDING AND REPRODUCING INFORMATION TO AND FROM AMAGNETO-OPTICAL STORAGE MEDIUM THAT INCLUDES A FIRST MAGNETIC LAYER FOR RECORDING AT LEAST INFORMATION, A SECOND MAGNETIC LAYER FOR REGULATING A SWITCHED CONNECTIVE FORCE, AND A THIRD MAGNETIC LAYER FOR SHIFTING A MAGNETIC WALL OF RECORDED MARKINGS FOR INFORMATION REPRODUCTION. THE THREE LAYERS BEING STACKED ON A TRANSPARENT SUBSTRATE TO MAKE UP THE STORAGE MEDIUM. THE INFORMATION RECORDING/REPRODUCING APPARATUS INCLUDES AN OPTICAL HEAD (19) AND A MAGNETIC HEAD (18). THE OPTICAL HEAD (19) HAS A LIGHT SOURCE AND AN OBJECTIVE LENS, THE LIGHT SOURCE IS CONFIGURED TO EMIT AT LEAST A LASER BEAM WITH A WAVELENGTH OF ABOUT 780 NM, THE OBJECTIVE LENS HAVING A NUMERICAL APERTURE OF ABOUT 0.45 AND IS CONFIGURED TO FOCUS THE LASER BEAM FROM THE LIGHT SOURCE INTO A BEAM SPOT FOR EMISSION ONTO THE MAGNETO-OPTICAL STORAGE MEDIUM. THE MAGNETIC HEAD (18) IS FOR APPLYING A RECORDING MAGNETIC FIELD TO THE MAGNETO-OPTICAL STORAGE MEDIUM.