Optical recording/reproducing medium-use substrate, production method for optical recording/reproducing medium reproducing stamper and optical recording/reproducing medium producing stamper

摘要

An optical recording/reproducing medium having grooves (2) formed along recording tracks and used for recording/reproducing when irradiated with light L with a specified wavelength λ, wherein the track pitch p of a groove (2) is at least 200 nm and up to 350 nm, and a ratio w_g/p between the width w_g of a groove (2) and a track pitch p is at least 0.24 and up to 0.67.