| 摘要 |
PURPOSE:To attain a recording erasing system strong for a tracking offset and a disturbance by erasing a domain written with a larger laser spot with the laser spot to have a smaller spot diameter. CONSTITUTION:A laser needle to have a different spot diameter on a noncrystal medium for a writing means and an erasing means, and the erasing of recording data is executed by illuminating a magnetic domain surface 8 formed by a recorder to have a larger laser spot diameter with an erasing needle to have the smaller laser spot diameter. That is a width (a) of the domain 8 is larger than an effective diameter (b) of an erasing beam 9. Consequently, the erasing beam is abutted on the domain which is an old data in a width direction with enough room, when the beam is cut before it runs out from the domain, the magnetic domain walls of a concentric circle shape is generated surely and the domain erases. Thus, an erasing method particularly strong for an offtrack can be offered. |
