Optical disk high-speed search control device

Claim 1

An optical disk high-speed search control device which directly counts the number of tracks of an optical disk and searches for a target track at high speed, said device comprising: a speed detector for counting pulses of a track traverse signal detected by an optical pickup and generating a speed detecting signal indicative of optical pickup movement speed, said speed detector including: (i) a first waveform shaper for shaping the signal detected by said optical pickup; (ii) a doubler for doubling the frequency of the signal shaped by said first waveform shaper; (iii) a first impulse converter for converting the signal output from said doubler into an impulse signal; (iv) an impulse delayer for delaying the impulse signal output from said first impulse converter by one cycle of the impulse signal; (v) first OR means for performing a logical sum operation on the delayed impulse signal and an error correction signal; (vi) a synchronized counter for counting a clock signal during a half cycle of the impulse signal; (vii) a latch for latching the value calculated by counting the clock signal during a half cycle of the impulse signal; (viii) a memory for storing speed reduction/acceleration data corresponding to a jump speed for moving the optical pickup; and (ix) a digital-to-analog converter receiving the speed reduction data from said memory for converting the acceleration data into an analog speed signal; a track number counter for counting the pulses of the detected track traverse signal in accordance with an intended transfer direction; a speed controller for converting the pulses counted by said track number counter into a reference speed signal in accordance with a track jump command; and a drive speed generator responding to the reference speed signal and speed detecting signal to generate a drive speed signal for the optical pickup.