Liquid crystal driving signal generating apparatus and optical disk reproducing apparatus with liquid crystal driving signal generating apparatus

An optical disk reproducing apparatus with a liquid crystal driving signal generating apparatus, comprising:

• a liquid crystal panel disposed between a light source and an objective lens;
• a PWM signal generator;
• a low pass filter for limiting a frequency band of a PWM signal outputted from said PWM signal generator to generate a liquid crystal drive signal;
• means for detecting a tilt angle of a disk;
• and
• a control means for determining a refractive index to be set in said liquid crystal panel for correcting wave surface aberration caused by the tilt angle, and for controlling said PWM signal generator such that said PWM signal generator generates a PWM signal according to a duty ratio corresponding to the refractive index determined.