| 摘要 |
PURPOSE:To achieve the stabilization of tracking controlling by vibrating the projection beam to a recording medium and detecting the reflected components thereof. CONSTITUTION:A beam 4 is projected 3 to a medium 1 which has been recorded with information such as composite PCM signals including synchronizing signal, etc. through arraying of optically detectable unit recording regions. For the purpose of scanning, the medium 1 and apparatus 3 are moved and driven 5, 2 and the information is detected 13 by the reflected beam from the medium 1. Within the information detection range, the beam 4 is vibrated 10 and from the detection outputs, the vibtating frequency components of the beam 4 are detected 28 and the phase thereof and the phase of a reference signal 29 are compared to form 31 a tracking control signal, based on which controlling 23 is so performed as to project the beam 4 in the position optimum for information tracks. |
