OPTICAL RECORDING AND REPRODUCING MEDIUM SUBSTRATE, MANUFACTURING METHOD OF OPTICAL RECORDING AND REPRODUCING MEDIUM MANUFACTURING STAMPER AND OPTICAL RECORDING AND REPRODUCING MEDIUM MANUFACTURING STAMPER

摘要

In an optical recording and reproducing medium having a groove 2 formed along a recording track and which is recorded and/or reproduced with irradiation of light L having a predetermined wavelength lambda, a track pitch p of the groove 2 is selected in a range of from 200 nm to 350 nm and a ratio wg'/p between a width wg of the groove 2 and the track pitch p is selected in a range of from 0.24 to 0.67.