Abstract: In an optical disc having a multilayer structure in which recording layers are bonded to each other, the number of times additional writing can be performed is increased. A method for controlling an optical disc device according to the present invention comprises steps of calculating a displacement amount generated when the recording layers are bonded to each other; and identifying the size of a recordable area in a non-usable area predetermined on the recording layer based on the displacement amount.

Abstract: Disc inherent information read from a disc, such as management information, etc., are stored in a disc inherent information storage memory. The time of opening/closing a tray close detection switch is determined from the timer value of a tray open/close time measurement timer. If this timer value is smaller than a prescribed time, the management information of the disc which has been loaded before a disc ejection process is read from the disc inherent information storage memory for resuming the play of the recording medium.