Patent ID: 7502308

Claim:
An optical recording medium having spirally or concentrically formed tracks defined by lands and grooves and capable of an optical recording, the optical recording medium comprising a data recording and reproducing area divided into a plurality of zones in the radial direction, one zone being divided into a plurality of sectors respectively having an address area including pits having address information and a data area in which data is only present in the grooves and configured for recording and reproducing of data, and the number of sectors forming each zone being different, wherein, the address area includes an extra groove within a land in which the address data is present; and an average quantity of reflecting light Iemboss of the address area and an average quantity of reflecting light Idata of the data area satisfy a relation expressed by 0.7≦(Iemboss/Idata)≦1.3 due to the presence and configuation of the extra groove in the address area and the presence of the address data within the extra groove.