Abstract A track-jump device for a disc drive apparatus for jump from one track to a neighboring track on a disc-like recording medium. A tracking error signal S TE , an on-track signal S OT whose phase is deviated by 90° relative to the tracking error signal according to displacement in the direction of track width and which exhibits a peak value when it is on the track, a signal S TE having a phase opposite to the tracking error signal, and signal S OT having a phase opposite to the on-track signal are successively switched by a switch (20) and are sent to a tracking device circuit (27) to effect the track-jump. The servo operation is continued even during the track-jump, and the servo loop is not interrupted. Therefore, track-jump is effected while maintaining advantage in regard to safety, reproducibility, and compatibility of pickups.
A disc drive track-jump system for effecting track-jump from one track to an adjacent track on a disc-shaped recording medium, comprising: a disc-shaped recording medium having a recording format in which servo signal regions and data signal regions are provided alternately along a circumferential direction of the disc, and wherein servo signals are recorded in the servo signal regions and at least data signals are recorded in the data signal regions; servo signal detection means being provided for detecting the servo signals in the servo signal regions; circuit means connected to receive said servo signals of said servo signal detection means for generating a tracking error first signal, an on-track second signal dephased by 90° from said tracking error first signal and reaching a peak value when it is disposed on a track, a reverse-phase third signal of said tracking error first signal and a reverse-phase fourth signal of said on-track second signal; switching means for sequentially switching the four signals and outputting the respective signal after each switching has occurred; and tracking control circuit means connected to receive the four sequentially switched signals for effecting track-jump from one track to an adjacent track.
Claim 2
Dependent Claim
194 words
A disc drive track-jump system for effecting track-jump from one track to an adjacent track on a disc-shaped recording medium, comprising: a disc-shaped recording medium having a recording format in which servo signal regions and data signal regions are provided alternately along a circumferential direction of the disc, and wherein servo signals are recorded in the servo signal regions and at least data signals are recorded in the data signal regions; servo signal detection means being provided for detecting the servo signals in the servo signal regions; circuit means connected to receive said servo signals of said servo signal detection means for generating a tracking error first signal, an on-track second signal dephased by 90° from said tracking error first signal and reaching a peak value when it is disposed on a track, a reverse-phase third signal of said tracking error first signal and a reverse-phase fourth signal of said on-track second signal; switching means for sequentially switching the four signals and outputting the respective signal after each switching has occurred; and tracking control circuit means connected to receive the four sequentially switched signals for effecting track-jump from one track to an adjacent track.
Claim 3
Dependent Claim
66 words
The disc drive track-jump system according to claim 1 wherein each servo signal region has a recording pattern including a pair of tracking servo pits formed on both sides of a track center line, and pits are formed on a center line of the track for reference clock reproduction, and wherein said servo detection means detects said tracking servo pits and said reference clock reproduction pits.
Claim 4
Dependent Claim
58 words
The disc drive track-jump system according to claim 2 including sample and hold means connected to an output of optical detection means for detecting the servo signals on the disc-shaped recording medium and timing pulse generation means also connected to an output of said optical detection means for creating sampling pulses fed to said sample and hold means.