Patent ID: 6501728
Filing Date: 2002-12-31
Classification: G11B

Abstract:
An optical recording medium in which a recording section constituted of at least a first dielectric layer, a first recording layer, a second recording layer, and a second dielectric layer is sequentially formed on a transparent substrate, and a reflective layer and a protective layer are formed on the recording section, whereina groove is formed on the transparent substrate along a recording track, both sidewalls of the groove are respectively formed into an independent wobbling shape (to be formed into a zigzag shape; hereafter referred to as wobbling), the relation of 0.470&lE;W/Ã˜&lE;0.610 is effectuated when assuming the width of the groove as W, the relation of 0.120&lE;D/(&lgr;/n)&lE;0.142 is effectuated when assuming the depth of the groove as D, and the angle &thgr; formed between wall faces of the groove is kept at 150Â°Â±10Â°(In the above expressions, Ã˜ denotes the spot diameter of a laser beam to be irradiated, &lgr; denotes the wavelength of a laser beam in a vacuum state, and n denotes the refractive index of a transparent substrate).