Patent ID: 8400896

Claim:
An information recording and reproducing apparatus that records and reproduces information in/from an information storage medium having a plurality of information storage layers of two or more different types, the information recording and reproducing apparatus comprising: accessed layer determining means for determining an accessed information storage layer, which is an information storage layer that is accessed among the plurality of information storage layers; accessed layer type identifying means for identifying a type of the accessed information storage layer thus determined by the accessed layer determining means; layer number obtaining means for obtaining layer number information that is recorded in the accessed information storage layer and discriminates the accessed information storage layer from the rest of the plurality of information storage layers; and layer type information obtaining means for obtaining layer type information indicating the type of the accessed information storage layer, wherein the accessed layer determining means determines the accessed information storage layer, based on the layer number information obtained by the layer number obtaining means, the accessed layer type identifying means identifies the type of the accessed information storage layer, based on the layer type information obtained by the layer type information obtaining means; the number information is included in address information recorded in each information storage layer; and wherein: the address information is recorded in an address information storage region of each information storage layer; each type of information storage layer stores the layer number information at a different storage location in the address information storage region thereof; and the layer number obtaining means obtains the layer number information at the storage location corresponding to the type of the accessed information storage layer.