US05844882Recording medium, address recording method and apparatus, and recording/reproducing method and apparatus for reducing crosstalk of addressing signals
AssigneeSony Corporation
Assign./FiledDec. 1, 1998/ March 17, 1997
InventorsYoshida; Tadao, Nonaka; Chiaki
SummaryImprovement to allow accurate, low cross-talk ADIP tracking even with small track pitch. (Beneficial for 80 minute blanks with 1.5um pitch?). Includes very careful description of how ADIP tracking is accomplished.
AbstractEdges on both sides of each groove on a disk 11 are wobbled to indicate the addresses of recording locations. A laser beam for detection of data is radiated to a land for recording data, forming a spot 51-1. Two laser beams for detection of a tracking error are radiated to edges on both sides of a groove in such a way that the middle between the two laser beams coincides with the center of the groove, forming spots 51-2 and 51-3. By using such a tracking-error detecting laser beam to read out address information, the laser beam can be radiated to only the edge on a predetermined side of a groove. As a result, an address can be read out with a reduced amount of crosstalk from another groove even if the track pitch is small. Address information is thus read out with a highly accurate degree even in the case of a small track pitch.