Optical recording medium

Abstract

Abstract PURPOSE:To obtain a recording medium high in sensitivity with high CN ratio without requiring a reflecting layer by forming a coloring matter (component) layer on the whole surface of the grooved side of a substrate having a tracking groove on one side and transparent for both writing and reading light as a recording layer. CONSTITUTION:The tracking grooves 3 having depth (d) are formed on one side of the base body 2 transparent for the recording and writing light and the whole area including the grooves 3 is coated with an optical recording layer 4 containing cyanic coloring matter or the coloring matter and resin, or quencher for improving the light resistance of the coloring matter with the thickness (t) by a coating method. If it is defined that any one of recording layer 4 out of the recessed part and the projected part of the grooves 3 is set up as a recording track part and the recording layer thickness providing the maximum reflection factor to the reading light is t0, 0.7t0<=t<=1.3t0 is formed, the reflection factor of the reading light (shown by the arrow) through the substrate is >=20% and the light is irradiated through the substrate to form a recording pit. When the wavelenght of the writing and reading light is 750-840nm, (t) is 0.04-0.10mu (d) is set up so that the relation between the (d) and wavelength lambda satisfies the shown formula. Thus, a highly sensitive recording medium is obtained.

Inventors

• 👤 Toshiki Aoi
• 👤 利樹 青井
• 👤 Kazuo Takahashi
• 👤 一夫 高橋
• 👤 Shigeru Asami
• 👤 浅見　茂
• 👤 Akihiko Kuroiwa
• 👤 黒岩　顕彦
• 👤 Noriyoshi Nanba
• 👤 憲良 南波

Bibliographic Details