| 摘要 |
PURPOSE:To rewrite information with a high reliability by equalizing the shapes and areas of irradiated areas on a recording medium of two energy beams and allotting the portions of functions to two energy beams to rewrite recorded information. CONSTITUTION:Two energy beams are used, and the shapes and areas of irradiated areas on the recording medium of two energy beams are approximately equalized, and the portions of functions to rewrite recorded information are allotted to two energy beams. Two energy beams may be generated by two energy sources independent of each other like two semiconductor lasers or by a unified laser array. One beam from one energy source may be bisected. It is preferable that tracking and track addresses of these two beams are confirmed independently of each other. Thus, information rewrite (overwrite) is surely performed in an information storage device like an optical disk. |
