| 摘要 |
<p>The present invention relates to instantaneous monitoring of information recorded on a videodisc. In the prior art, it has not been possible to accurately determine the quality of a recorded videodisc until after completing the recording process. The present invention overcomes this problem by providing an improved apparatus and method for instantaneously checking information recorded on a videodisc. In accordance with the invention, the instantaneous monitoring system includes a comparator for comparing a video output information signal developed from reading a videodisc with a video input signal used to write information on the videodisc. Further included is an F.M. modulator for converting the voltage varying with time signal to a frequency modulated signal. A writer is provided for storing the frequency modulated signal upon a light responsive videodisc in the form of alternate regions of high and low directional reflectivity normal to the surface of the disc. A sensor, responsive to the reflected light, is used for recreating the frequency modulated signal, and a modulator responsive to the output of the sensor produces a voltage varying with time output video information signal. The comparator output is used to verify the quality of the information being stored on the videodisc.</p> |
