Optical recording track access driving apparatus

An optical recording medium driving apparatus using an optical recording medium having alternate lands and grooves in a radial direction of the optical recording medium, the apparatus having an optical head for projecting a light beam onto the optical recording medium and for receiving a reflected light beam from the optical recording medium, the reflected light beam bearing a reproduction signal, comprising:

• first low frequency component removing means for removing a low frequency component from the reproduction signal;
• reference voltage generation means for outputting first reference voltage during performing a tracking operation and for outputting second reference voltage during performing a track access operation;
• second low frequency component removing means, having a time constant substantially identical with a time constant of said first low frequency component removing means, for changing an output of said reference voltage generation means according to said time constant;
• and
• comparator means for comparing an output of said first low frequency component removing means to the output of said second low frequency component removing means.

A method for driving an optical recording medium having alternate lands and grooves in a radial direction thereof by projecting a light beam onto the optical recording medium and receiving a reflected light beam from the optical recording medium, the reflected light beam bearing a reproduction signal, comprising the steps of:

• (a) removing a low frequency component from the reproduction signal contained within the reflected light beam;
• (b) generating a slice level which varies depending on the reproduction signal from which the low frequency component is removed
• (c) performing step (b) at a time shifting from tracking operation to track access is performed;
• and
• (d) comparing the slice level generated in step (b) to the reproduction signal from which the low frequency component was removed in step (a).