Optical disk apparatus

An optical disk apparatus for use with a recordable optical disk, comprising:

• clock signal generator means configured to generate standard clock signals for timing data recording such that a location of a data recording restart following an interruption of recording on said optical disk coincides precisely with that of an end of a previous recording,
• wherein:
• said clock signal generator means comprises
• voltage control oscillator means for generating and then outputting a clock signal having a frequency corresponding to an input control voltage,
• variable divider means for frequency dividing said clock signal output from said voltage control oscillator means with a dividing ratio that is variable depending on an input control voltage,
• fixed divider means for frequency dividing a standard clock signal having a predetermined frequency with a predetermined dividing ratio,
• frequency and phase detector means for comparing both frequency and phase of a first signal generated by being frequency divided by said fixed divider means and a second signal generated by being frequency divided by said variable divider means, and then outputting a control voltage corresponding to comparison results;
• and
• dividing ratio controller means for comparing both frequency and phase of a frame synch signal, provided for each frame of data on said optical disk and acquired during playback period of recorded data, and a clock signal output from said voltage control oscillator means, and subsequently controlling said variable divider means to have a dividing ratio that is variable and depends on comparison results.

A method of generating clock signals for timing events in recording new data on an optical disk following an interruption in recording of previous data, such that the recording of new data following said interruption would start substantially where the recording of the previous data ended on the disk, comprising:

• comparing both frequency and phase of a) a frame synch signal acquired in the course of playback of data recorded on said disk, and b) a clock signal from an oscillator, to thereby produce a first comparison signal,
• controlling a dividing ratio of a variable frequency divider as a function of said comparison signal, to thereby provide an output of said variable frequency divider;
• comparing said output of said variable frequency divider with a fixed frequency signal to thereby provide a second comparison signal;
• using said second comparison signal to control the clock signal from said oscillator;
• and
• recording new data on said disk following an interruption in recording of previous data thereon, using the clock signal from said oscillator to cause the recording of new data to start substantially where the recording of previous data ended on the disk.