| 摘要 |
PURPOSE:To attain high-speed synchronous drawing by increasing a sampling frequency by additionally inserting a sampled value of zero into sampling outputs of timing signal components. CONSTITUTION:Reference frequency (fo) is sent to divider 3 by way of divider circuit 1 and pulse control circuit 2 to form sampling pulse (fs). A timing signal component of frequency (ft), on the other hand, is sampled 4 and then applied to sample interpolation circuit 5, which inserts the (k-)-number sampled values into sampled values in each period of 1/fs. Then, timing component extraction circuit 6 with a narrow-band filter removes noises, etc., so that the output of circuit will be a timint signal of sampling frequency kfs. In this way, a zero cross point is detected 7 at a high speed, the needed number of shift pulses is set 8 and circuit 2 samples output pulses of divider circuit 1. In this way, synchronous drawing can be performed at a high speed. |
