| 摘要 |
PURPOSE:To facilitate control for the output of the writing beam in the information recording time, by expressing the information with the presence or absence of an information hole and a pair of information holes to the track of the inner circumference and the outer circumference respectively of an optical disk. CONSTITUTION:A pair of information holes a1, a2, a3... are provided only at the tip part and the rear edge part of the recording region R equivalent to a bit for the information on a track T1' of the track group G0 at the outer circumference part of an optical disk D. While information holes a'1, a'2, a'3... are provided in the region R for the information of a track T2' of the track group Gi at the inner circumference part. When the track belongs to the inner circumference part Gi, contact bars E1 and E2 are connected to terminals P1 and P2. The signal sent from a writing data generating part S is fed to a laser modulating part M, and the light given from a laser light source L undergoes the luminance modulation M. While the bars E1 and E2 are connected to terminals P3 and P4 when the track belongs to the outer circumference part G0. Thus the laser beam is controlled in response to the output pulse given from a monostable multivibrator F. |
