Abstract text

An optical disc apparatus can highly accurately record a hologram representing information on or reproduce such a hologram from an optical disc. When recording information on an optical disc 100, the optical disc apparatus controls the position of an objective lens OL1 according to the outcome of detection of a red reflected light beam Lr2 so as to make the focus Fr thereof follow a target track and it also makes the focus Fb1 of a blue light beam Lb1 agree with a target mark position by the objective lens OL1 and also the focus Fb2 agree with the target mark position by controlling the position of another objective lens OL2 according to the outcome of detection of the blue light beam Lb1 by way of the objective lenses OL1 and OL2 so as to make the focus Fb1 of the blue light beam Lb1 and the focus Fb2 of the blue light beam Lb2 agree with the target mark position and the blue light beam Lb1 and the blue light beam Lb2 interfere with each other. Thus, as a result, the optical disc apparatus can record a recording mark RM at the target mark position.