Patent ID: 7964337
Filing Date: 2011-06-21
Classification: G11B

Abstract:
1. A method of producing an optical recording medium, wherein an optical recording layer formed on a medium substrate and a light transmitting-protective layer thereon are provided, and said optical recording layer is irradiated with a light through the protective layer, including the steps of: forming an optical recording medium producing master disk having a main surface with a signal portion and a character portion, the signal portion having concave and convex shapes, and the character portion having concave and convex shapes; forming a master stamper by transferring said signal portion concave and convex shapes and said character portion concave and convex shapes from said optical recording medium producing master disk; forming a mother stamper by transferring said signal portion concave and convex shapes and said character portion concave and convex shapes from said master stamper; forming a medium substrate by transferring said signal portion concave and convex shapes and said character portion concave and convex shapes from said mother stamper; forming an optical recording layer on a formation surface of said signal portion concave and convex shapes and said character portion concave and convex shapes on said medium substrate; and forming a light transmitting protective layer on said optical recording layer; wherein characters are recorded to be able to be read as normal characters on said optical recording medium producing master disk by outlines of regions formed with said character portion concave and convex shapes on said character portion in said step of forming said optical recording medium producing master disk, wherein said signal portion concave and convex shapes and said character portion concave and convex shapes are formed to have a depth of 25 nm or less in the step of forming said optical recording medium producing master disk.