| 摘要 |
PURPOSE:To prevent a bad influence exerted on a tracking control signal due to a variation of a recording laser beam, by recording the tracking control signal on both sides of an information signal, at the same time. CONSTITUTION:As for a laser light beam emitted from a laser light source 40, its intensity is modulated by an information signal in an optical modulator 10, and an image is formed as shown by 21 on an optical disk D. Also, as for the laser beam reflected by a half-mirror 9, its intensity is modulated by a tracking control signal in optical modulators 22, 28, and images 34, 35 are formed on the optical disk D. According to such constitution, even if a short-time output drop or output stop occurs in the laser light source, the tracking control signal is a nonrecording state at the same time on both sides of an information signal, therefore, when reproducing, the tracking control operation does not go out of order. |
