In an optical information recording medium having at least two information layer, guide grooves for tracking or sample pits or information pits corresponding to information signals are formed on a surface of a first substrate. A first information layer formed by a thin film for reflecting a portion of a light beam made incident on the first substrate and permitting penetration of a portion of the light beam is formed on a surface of the first substrate. Guide grooves for tracking or information pits corresponding to information signals are formed on a surface of a second substrate. A second information layer having a reflectance higher than that of the first information layer is formed on a surface of the second substrate. Between the first information layer and the second information layer, there is formed a transparent separation layer for positioning the first information layer and the second information layer to be spaced a predetermined distance apart from each other.

Claims

5 · 4 independent · depth 2

5 granted claims

›1.independentAn optical information recording medium, comprising:na first substrate having, on one side thereof, pits or guide grooves;a first information layer fo…

›2.independentAn optical information recording medium, comprising:na first substrate having, on one side thereof, pits or guide grooves;a first information layer fo…+1

›4.independentAn optical information recording medium, comprising:na first substrate having, on one side thereof, pits or guide grooves;a first information layer fo…

›5.independentAn optical information recording medium, comprising:na first substrate having, on one side thereof, pits or guide grooves;a first information layer fo…

Classifications

3 codes

IPC · International Patent Classification

Section G — Physics

G11B7/24

USPC · US Patent Classification

369/275.4369/283

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File wrapper

Pendency

1.9 y

679 days filing → grant

Office actions

non-final + final

Responses

1 RCE

Examiner

Paul W. Huber

art unit 2653 · TC 2600

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Citations: 54 back · 0 forward

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Priority chain

1 priority documents

›Priority documents — 1

Type	Document	Date
related publication	US 20040223445 A1	11 Nov 2004

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