Optical disc apparatus and information recording and reproducing method

An information recording/reproducing method for recording information onto or reproducing information from an optical disc having a first recording layer and a second recording layer, the information recording/reproducing method comprising:

• a first step of setting a plurality of virtual zones corresponding to a plurality of zones arranged in a radialdirection of the optical disc for a plurality of recording layers of the optical disc;
• a second step of recording information onto or reproducing information from a first recording layer of the optical disc and detecting a distortion in a tracking servo signal or in a focus servo signal;
• a third step of changing, when the distortion is detected, a rotation speed of the optical disc to a low speed at a position in a virtual zone of a first recording layer in which the distortion is detected;
• a fourth step of storing as change information the virtual zone of the first recording layer in which the rotation speed is changed, and continuing a recording or reproducing operation;
• a fifth step of proceeding to a second recording layer, and judging whether the rotation speed of the optical disc is changed to a low speed in a virtual zone of the first recording layer that corresponds to the virtual zone of the second recording layer in accordance with the stored change information before a recording or reproducing operation is performed in a virtual zone of the second recording layer;
• a sixth step of setting the rotation speed of the optical disc in all over the virtual zone of the second recording layer in the same rotation speed of the optical disc as the low speed changed in the virtual zone of the first recording layer when the obtained judgment result indicates that the rotation speed is changed to a low speed;
• a seventh step of performing a recording or reproducing operation in the virtual zone at the selected low rotation speed;
• an eighth step of judging, before proceeding to the next adjacent virtual zone from a virtual zone in which a recording or reproducing operation was performed in the seventh step and performing a recording or reproducing operation in the next virtual zone, whether the rotation speed of the optical disc is changed to a low speed in a virtual zone of the first recording layer that corresponds to the next virtual zone;
• a ninth step of changing the rotation speed of the optical disc in all over the next virtual zone to a low speed when the obtained judgment result indicates that the rotation speed for the virtual zone of the first recording layer is changed to a low speed, and changing or maintaining the optical disc for the next virtual zone to a predetermined rotation speed without switching to a low speed when the obtained judgment result indicates that the rotation speed for the virtual zone of the first recording layer is not changed to a low speed;
• a tenth step of performing a recording or reproducing operation in the next virtual zone at the selected low rotation speed;
• and
• an eleventh step of repeating the eighth step, the ninth step, and the tenth step when a recording or reproducing operation is to be performed in the second next virtual zone of the second recording layer.

An information recording/reproducing method in an optical disc apparatus for recording information and/or reproducing information on/from an optical disc having a first recording layer and a second recording layer, the information recording/reproducing method comprising:

• setting a plurality of virtual zones corresponding to a plurality of zones arranged in a radial direction of the optical disc for a plurality of recording layers of the optical disc;
• detecting a distortion in one of a tracking servo signal and a focus servo signal, while a recording or reproducing operation is performed in a certain virtual zone in a first recording layer of the optical disc;
• changing a rotation speed of the optical disc to a lower speed at a position in the virtual zone in the first recording layer of the optical disc, where the distortion in one of the tracking servo signal and the focus servo signal is detected;
• storing change information when the rotation speed of the optical disc is changed to a lower speed at the position in the virtual zone in the first recording layer of the optical disc;
• setting, before a recording or reproducing operation for the second recording layer is performed, the rotation speed of the optical disc in all over a virtual zone which is set in the same radial position of the second recording layer as that of the virtual zone of the first recording layer, in the same rotation speed of the optical disc as the low speed changed in the virtual zone of the first recording layer, in accordance with the change information;
• and
• making the optical disc rotate at the set rotation speed and performing the recording or reproducing operation for the virtual zone of the second recording layer.