OPTICAL DATA RECORDING MEDIUM AND RECORDING AND PLAYBACK METHOD

摘要

A disc-shaped optical data recording medium (110) has a signal recording layer (103) for reading and/or writing data using light, and a 10 µm to 200 µm thick transparent protective layer (102) disposed over the signal recording layer (103). The optical data recording medium (110) includes a protrusion (100) projecting from the surface of the transparent protective layer (102) on the light-incidence surface side to which light is emitted to the signal recording layer (103). The protrusion (100) is disposed in an area between a center hole (101) and a clamping area (CA) where the optical data recording medium (110) is held when reading and/or writing data in the signal recording layer (103).