Patent ID: 7869330

Claim:
An optical disc apparatus reproducing information on the basis of a standing wave recorded on a disc-like volume type recording medium, comprising: a first focus position adjusting means for adjusting the position of a focus on which a first light beam focuses inside a recording layer inside the volume type recording medium in the optical axis direction of the first light beam; a second focus position adjusting means for adjusting the position of a focus on which a second light beam focuses inside the recording layer in the optical axis direction of the second light beam; a controlling means for controlling the first focus position adjusting means and the second focus position adjusting means so that, when the standing wave is recorded on the volume type recording medium, the first light beam focuses inside the recording layer and the second light beam transmitted through the recording layer and then reflected by a predetermined reflection face focuses on the same position as the first light beam focuses and, when information is reproduced on the basis of the standing wave on the volume type recording medium, the position of the focus on which the first light beam focuses inside the recording layer and the position of the focus on which the second light beam focuses inside the recording layer are different from each other, thereby generating first and second reproduction light beams from standing waves different from each other; and first and second detecting means for detecting the first and second reproduction light beams.