Patent ID: 8675460

Claim:
An optical disc device for reading information recorded on an optical disc medium, comprising: an objective lens for focusing light onto the optical disc medium; a plurality of light-receiving elements arranged in an array, each for receiving reflected light from the optical disc medium and outputting an output signal corresponding to a light amount of the reflected light; a plurality of amplifiers each for amplifying the output signal output from a corresponding one of the plurality of light-receiving elements; a signal output circuit for outputting, based on amplified signals respectively output from the plurality of amplifiers, a focus error signal indicating a deviation of a focal position of the objective lens with respect to a signal surface of the optical disc medium; a focus servo control unit for controlling, based on the focus error signal, a position of the objective lens so as to keep constant a distance between the objective lens and the signal surface; a position adjusting unit for moving the objective lens to a first temporary in-focus position, and then moving said objective lens to a second in-focus position at which accuracy of reading the information from the optical disc medium becomes higher than at the first temporary in-focus position; and a gain adjusting unit for adjusting a gain of each of the plurality of amplifiers after said objective lens has been moved to said second in-focus position, so that levels of the amplified signals respectively output from the plurality of amplifiers become close to each other, wherein the first temporary in-focus position is a position of the objective lens where the focus error signal is adjusted, wherein the second in-focus position is a position of the objective lens where the focus servo control unit moves the objective lens to the second in-focus position based on a focus bias value and the plurality of amplifiers are adjusted after adjusting for the focus error signal, and wherein the focus bias value is adjusted based on reading an evaluation value.