Patent ID: 8675463

Claim:
An optical disc driving device comprising: an optical pickup unit for converting read light into an electric signal, the read light being acquired by the optical pickup unit by applying light to a multilayered optical disc from which information can be read from one side thereof and which has a recording surface in each of at least a first layer and a second layer; a control circuit for performing a gain adjustment for each of the first and second layers of the recording surface based on a focus error signal generated from said electric signal, said performing a gain adjustment being accomplished so as to maintain a state in which the optical pickup unit focuses the applied light onto the recording surface in either of the first and second layers, generating a focus loop signal for controlling a focus servo loop, and generating a focus jump signal from a threshold, said threshold being based on an amount of gain adjustment acquired as a result of said performing a gain adjustment; and a focus actuator driving circuit for driving said optical pickup unit based on either the focus jump signal or the focus loop signal so as to either perform a focus jump or maintain the state in which the applied light is focused.