Patent ID: 7577070

Claim:
An optical recording medium tilt compensation device comprising: an object lens that condenses light from a light source on a recording surface of an optical recording medium; an object lens tilt actuator that controls a tilt of the object lens; an object lens tilt sensor that detects the tilt of the object lens; an optical recording medium tilt sensor that detects a tilt of the optical recording medium; a control unit that controls the tilt of the object lens in accordance with a tilt value from the optical recording medium tilt sensor so that an aberration of the spot condensed on the recording surface is made minimum by driving the object lens tilt actuator; and a gain variable unit that changes a magnitude of an output signal from the object lens tilt sensor or the optical recording medium tilt sensor, wherein the gain variable unit changes the variable gain stepwise, and wherein one of the settings of the stepwise variable gain is zero.