Tilt servo apparatus for use in optical disc reproducing apparatus

A tilt servo apparatus for use in an optical disc reproducing apparatus having an optical pickup which comprises at least a laser light source, an objective lens, a liquid crystal panel for an aberration correction on which formed is a transparent electrode divided into segments of predetermined shapes, and a photodetector element, and which irradiates a laser beam emitted from said laser light source onto an information recording surface of an optical disc via said liquid crystal panel for the aberration correction and said objective lens, thereby forming a light spot, and receives, at said photo detector element, reflection light being obtained, thereby reading a signal corresponding to information to be recorded on the optical disc, said tilt servo apparatus comprising:

• tilt detecting means for detecting a signal representing a tilting angle in a radial direction between the information recording surface of said optical disc and an optical axis of said objective lens;
• and
• a driving circuit for variably driving voltages applied to said divided portions of said liquid crystal panel, respectively, said driving circuit performing a driving operation in which predetermined voltages are applied to the respective divided segments of said liquid crystal panel in accordance with a detection output of said tilt detecting means and a phase difference between respective laser beams passing through the divided segments is adjusted, thereby correcting an aberration of said objective lens tilted at the tilting angle with respect to the information recording surface of said optical disc.