IP Library › Granted Patent US 7,570,574
Granted Patent B2
US 7,570,574 · App. 11/876,049 · Granted Aug 4, 2009

Information recording medium

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Quick Facts
Patent No.
US 7,570,574
App. No.
11/876,049
Granted
Aug 4, 2009
Kind
B2
Abstract

In an information recording medium comprising at least a substrate, a recording layer, and a resin layer, the substrate is formed with at least a pit corresponding to a read only area 31 and a groove corresponding to a recording/reproducing area 32 without overlapping with each other. A reflectivity of the recording layer is specified to be more than 10%. The recording layer and the resin layer are continuously adhered over both the read only and recording/reproducing areas 31 and 32 . The information recording medium is characterized in that both push-pull signal outputs T 1 and T 2 , which are reproduced from the read only area 31 and the recording/reproducing area 32 respectively, are more than 0.1 and satisfy an inequality 1.5≧T 1 /T 2 ≧0.5.

Claims (16)

1. An information recording medium comprising at least a substrate, and a recording layer,

wherein said substrate is formed with a read only area and a recording/reproducing area, and wherein said read only area and said recording/reproducing area do not overlap with each other, and

wherein said recording/reproducing area is composed of a groove and a land, and

wherein a reflectivity of said recording layer is more than 10%, and

wherein said recording layer is formed continuously over at least two areas of said read only area and said recording/reproducing area, and

wherein a push-pull signal output T 1 reproduced from said read only area is more than 0.1 and another push-pull signal output T 2 reproduced from said recording/reproducing area is more than 0.1, and wherein 1.5≧T 1 /T 2 ≧0.5, and

wherein an address pit is allocated to said land.

2. A reproducing method for reproducing an information recording medium comprising at least a substrate, and a recording layer,

wherein said substrate is formed with a read only area and a recording/reproducing area, and wherein said read only area and said recording/reproducing area do not overlap with each other, and

wherein said recording/reproducing area is composed of a groove and a land, and

wherein a reflectivity of said recording layer is more than 10%, and

wherein said recording layer is formed continuously over at least two areas of said read only area and said recording/reproducing area, and

wherein a push-pull signal output T 1 reproduced from said read only area is more than 0.1 and another push-pull signal output T 2 reproduced from said recording/reproducing area is more than 0.1, and wherein 1.5≧T 1 /T 2 ≧0.5, and

wherein an address pit is allocated to said land,

said reproducing method characterized in that

reproducing is conducted by irradiating a laser beam on said recording layer.