| 摘要 |
PURPOSE:To simplify a control circuit for driving a head by forming a titled medium in such a manner that a pair of spiral recording tracks formed respectively on information forming layers facing each other overlap on each other when viewed through from above. CONSTITUTION:The recording tracks 5h are spirally formed on the information forming layers 5c facing each other on an optical disk 5. The tracks 5e are so formed as to bulge outward in the radial direction according to the extension along the clockwise direction when viewed from below on the upper information forming layer 5c. On the other hand, the recording tracks 5h are so formed as to bulge outward in the radial direction according to the extension along the counterclockwise direction when viewed from above on the lower information recording layer 5c. More specifically, the recording tracks 5h formed on the upper and lower layers 5c appear to overlap on each other when the disk 5 is viewed through from above. The formation of the control circuits for driving the head 48 for processing the upper and lower recording tracks 5h into the same constitution is thus made possible and the cost is reduced. |
