The objective of the present invention is to facilitate to identify whether or not the optical disc is a optical disc of which recording capacity is enlarged. A synchronization pattern of ATIP information embedded into guide grooves irradiated with a light spot is made to be different between a high density optical disc and a standard density optical disc of which recording capacity is not enlarged. Specifically, while the synchronization pattern of the standard density optical disc is made into “3T+1T+1T+3T” (where “T” represents a minimum channel bit of a signal obtained by reading a positional information), the synchronization pattern of the high density optical disc is made into “3T+3T+1T+1T” for example. By reading the ATIP information and recognizing the synchronization pattern thereof, it can be easily and quickly identified whether the optical disc has a standard density or a high density.