OPTICAL DISK OF INTERGROOVE RECORDING SYSTEM

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(11)

EP 1 477 976 A8

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

(48)	Corrigendum issued on:
	19.01.2005 Bulletin 2005/03

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

(21)	Application number: 02788818.9

(22)	Date of filing: 13.12.2002

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

(86)	International application number:
	PCT/JP2002/013061

(87)	International publication number:
	WO 2003/063153 (31.07.2003 Gazette 2003/31)

(84)	Designated Contracting States:
	AT BE BG CH CY CZ DE DK EE ES FI FR GB GR IE IT LI LU MC NL PT SE SI SK TR
	Designated Extension States:
	AL LT LV MK RO

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Priority:

21.01.2002 JP 2002010987

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

(72)	Inventor:
	HIGUCHI, T., 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 OF INTERGROOVE RECORDING SYSTEM

(57) Hardness of a resin substrate of a disc is made greater than hardness of a cover layer of the disc so that a stress produced due to heat and expansion of an organic dye during information recordation is dispersed toward the cover layer. A laser beam passes through the cover layer. The hardness relationship between the cover layer and substrate should be established only when the information is recorded. This prevents deformation of the reflection layer during the information recording and crosswrite. Therefore, the disc can record finer information. Alternatively, the disc may be configured such that heat transfer toward the protection layer from the organic dye layer is greater than heat transfer toward the reflection layer from the organic dye layer. The organic dye layer is sandwiched between the protection layer and reflection layer.