| 摘要 |
PURPOSE:To obtain the optical recording medium of high density information and its recording and reproducing device by modulating the shape and length of a pit in the track direction of the optical recording medium and also in the track widthwise direction as orthogonal to this track direction respectively, the distance between the pits and the distance between a guide track and the pit. CONSTITUTION:Reflected light intensity at a sampling point is observed in two dimensions, i.e. in the track direction and in the track widthwise direction as orthogonal to this track direction at a sampling pitch to satisfy the sampling theorem. By filtering this reflected light intensity with a low pass filter 25 in the two dimensional directions, a distance is modulated in the two-dimensional directions, and two-dimensional position information for a multivalued and recorded pit is obtained. Since this position information is obtained in the way of satisfying the sampling theorem, information of high recording density is obtained from the optical recording medium 16 without depending upon the number of detectors and resolving force of them. |
