| 摘要 |
PURPOSE:To enable accurate reproduction of tracking signal without being affected with dust, by providing the stylus proove for control signal in parallel with the recording track of video signal. CONSTITUTION:On the surface of the video disc 1, a number of video tracks 4 are formed in spiral or concentrically. Near this track 4, the same stylus groove 5 as conventional mechanical groove of LP record disc is provided. The contact stylus 7 traces the groove 5 for control and the output is processed with the pickup and amplifier for control signal. Since the stylus groove 5 is used only for the rotary control of discs, the contact stylus 5 is almost not affected with the dirt of disc surface and attachment of dust, accurate tracking of laser light system is made and low cost video disc can be obtained without using expensive automatic control unit. |
