Recording clock generating apparatus for a data recording system

Abstract

A recording clock generating apparatus for a data recording system includes a wobble signal sampler which samples a wobble signal, from wobble grooves of an optical disk. A first phase comparator provides a first phase-difference signal based on a difference in phase between the wobble signal and a first recording clock signal. A prepit detector detects a prepit signal from prepits of the optical disk. A second phase comparator provides a second phase-difference signal based on a difference in phase between the prepit signal and the first recording clock signal. A phase control signal generator provides a phase control signal based on a sum of the first phase-difference signal and the second phase-difference signal. A clock generator provides a second recording clock signal having a phase corrected in response to the phase control signal provided by the phase control signal generator.

1 - 10 . (canceled)  
   
   
       11 . A data recording apparatus which records data on an optical disk, the optical disk having tracks of wobble grooves formed according to a wobble signal indicative of a predetermined frequency, and prepits formed with a given phase relation to the wobble signal, the data recording apparatus comprising: 
 a wobble signal sampler sampling the wobble signal from a signal obtained from the optical disk;    a prepit signal detector detecting the prepits from the signal obtained from the optical disk and outputting a prepit signal indicative of preformat information of the disk;    a clock generating circuit outputting a clock signal in accordance with a first signal based on the prepit signal and a second signal based on the wobble signal; and    a data generating part providing a recording data signal to be recorded on the optical disk, based on the clock signal.    
   
   
       12 . The data recording apparatus according to  claim 11 , wherein the first signal is a phase-difference signal based on a phase difference between the prepit signal and a feedback clock signal derived from the clock signal outputted by the clock generating circuit.  
   
   
       13 . The data recording apparatus according to  claim 11 , wherein the second signal is a phase-difference signal based on a phase difference between the wobble signal and a feedback clock signal derived from the clock signal outputted by the clock generating circuit.  
   
   
       14 . The data recording apparatus according to  claim 11 , further comprising an encoder providing a modulation signal based on the clock signal outputted by the clock generating circuit.  
   
   
       15 . The data recording apparatus according to  claim 14 , further comprising a control circuit performing a waveform correction for the modulation signal provided by the encoder, based on the clock signal outputted by the clock generating circuit.  
   
   
       16 . The data recording apparatus according to  claim 11 , wherein the clock signal is outputted in accordance with a signal indicating a sum of the first signal based on the prepit signal and the second signal based on the wobble signal.  
   
   
       17 . The data recording apparatus according to  claim 11 , wherein the clock signal is supplied by a voltage-controlled oscillator (VCO).  
   
   
       18 . The data recording apparatus according to  claim 11 , wherein the clock signal is outputted in synchronization with a rotation of the optical disk.