Clock generator

摘要

A clock generator for establishing working clock pulses occurring for constant increments in a scan path of a laser scanner which cyclically sweeps over a record medium at a non-constant velocity includes: a generator of a fiducial pulse at least once per cycle of sweep; a frequency synthesizer responsive to the fiducial pulses for generating radio-frequency clock pulses having a frequency greater than the fiducial pulses, and in synchronization therewith; a storage for storing a plurality of count values, each of the count values being associated with a given increment along the scan path; a working clock pulse generator, including a counter which counts the radio-frequency clock pulses, for emitting a working clock pulse each time the counter counts a count value received by the working clock pulse generator. For each working clock pulse a new count value stored in the storage is transmitted to the working clock pulse generator.