| 摘要 |
PURPOSE:To improve remarkably reproducing signal intensity (S) without increasing the temp. of pits by dividing a laser beam to plural beams having small intensity, providing a time difference thereto and irradiating one pit or the pits for one pit. CONSTITUTION:Information is recorded by two kinds of pits having upward and downward magnetization directions on a magnetic optical recording medium M consisting principally of a vertically magnetized film of GdTbFe or the like. Two laser light sources L1, L2 are used. The S-polarized beam B2 emitted from one light source L2 is bent by about 90 deg. in the advancing direction by a half prism HP and the two beams B1, B2 are made incident to a beam splitter PBS, where the two beams are bent 90 deg. and are irradiated to the pits of the medium M. The distance between the two beams B1 and B2 on the irradiated surface is made, for example, 4mum. Then a time difference of 0.22musec is eventually generated at the time when the two beams B1, B2 are irradiated to the same one pit. |
