OPTICAL DISK BY IN-GROOVE RECORDING METHOD

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(11)

EP 1 477 975 A8

(12)	CORRECTED EUROPEAN PATENT APPLICATION
	published in accordance with Art. 158(3) EPC

(48)	Corrigendum issued on:
	11.05.2005 Bulletin 2005/19

(43)	Date of publication:
	17.11.2004 Bulletin 2004/47

(21)	Application number: 02788817.1

(22)	Date of filing: 13.12.2002

(51)	International Patent Classification (IPC)⁷: G11B 7/24

(86)	International application number:
	PCT/JP2002/013060

(87)	International publication number:
	WO 2003/063152 (31.07.2003 Gazette 2003/31)

(84)	Designated Contracting States:
	DE FR GB

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Priority:

21.01.2002 JP 2002010986

(71)	Applicant: Pioneer Corporation
	Tokyo 153-8654 (JP)

(72)	Inventor:
	HIGUCHI, Takanobu, c/o Pioneer Corporation Tsurugashima-shi, Saitama 350-2288 (JP)

(74)	Representative: Klingseisen, Franz, Dipl.-Ing. et al
	Patentanwälte, Dr. F. Zumstein, Dipl.-Ing. F. Klingseisen, Postfach 10 15 61 80089 München 80089 München (DE)

(54)	OPTICAL DISK BY IN-GROOVE RECORDING METHOD

(57) An optical disk comprising a substrate, a reflecting layer, an organic pigment layer, a protective layer, and a cover layer. The hardness of the resin substrate side of the optical disk is set to be larger than the hardness of the cover layer side where a later beam transmits. The stress caused by the heat generation and expansion of the organic pigment when recording information is diffused to the cover layer side. The relationship of the hardness of both sides needs to satisfy the aforementioned relationship when recording information. This optical disk suited for the in-groove recording method can prevent deformation of a reflecting film when recording information and record more detailed information.