Patent attributes
An optical disc apparatus reproducing information on the basis of a standing wave recorded on a disc-like volume type recording medium includes: a first focus position adjusting unit configured to adjust 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 unit configured to adjust 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 controller configured to control the first focus position adjusting unit and the second focus position adjusting unit; and first and second detectors configured to detect the first and second reproduction light beams.