| 摘要 |
PURPOSE:To allow the recording of a larger quantity of data even with the same size by forming ruggedness having a saw tooth shape in sectional shape, concentrically or spirally, on the surface. CONSTITUTION:The ruggedness having the saw tooth shape in sectional shape is formed concentrically or spirally on the base body. The broader parts of the saw tooth-shaped ruggedness are used as recording regions and the steps on both sides thereof are used for obtaining a tracking error signal. Since the reflecting surfaces to constitute the recording regions are inclined, good reflection signals are obtd. by the oblique incidence of a laser beam. The high-density recording is possible in this way without impairing the signal quality. |
