Optical recording medium and method of producing same
AssigneeSony Corporation and Sony Disc Technology Inc.
InventorsToshiyuki Kashiwagi, Motohiro Furuki, Shoji Fukuchi, Yoshitake Yanagisawa
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Abstract
An optical recording medium capable of recording and/or reproducing an information by using a laser beam, comprising: a support layer having an information signal-recording portion on one side surface thereof on which said laser beam is incident, and a transparent layer disposed over the support layer and having a thickness smaller than that of the support layer. In accordance with the present invention, there are further provided production method for optical or magneto-optical discs whereby a high density reproduction can be achieved.
Claims21
An optical recording medium capable of recording and/or reproducing an information by using a laser beam, comprising:
- a support layer having an information signal-recording portion on one side surface thereof on which said laser beam is incident;
- and
- a transparent layer disposed over said support layer and having a thickness not more than 0.5 mm;
- and
- a reflective layer interposed between said support layer and said transparent layer.
An optical recording medium capable of recording and/or reproducing information by using a laser beam, comprising:
- a support layer having an information signal-recording portion on one side surface thereof on which said laser beam is incident;
- a transparent layer disposed over said support layer and having a thickness not more than 100 micrometers;
- and
- a reflecting layer interposed between said support layer and transparent layer.
A method of producing an optical recording medium, comprising the steps of:
- pouring a material for a substrate into a press while heating and subjecting the material to a compression molding to form the substrate having transferred information pits thereon;
- forming a reflecting layer over said substrate;
- and
- forming a transparent layer capable of permeating a laser beam and having a thickness not more than 0.5 mm over said reflecting layer.
A method of producing an optical recording medium, comprising the steps of:
- pouring a transparent resin into a press while heating, and subjecting the resin to a compression molding process to form a transparent layer having transferred information pits thereon;
- forming a reflecting layer having a thickness not more than 0.5 mm over said information pits formed on said transparent layer;
- and
- adhering said transparent layer onto a substrate having a thickness larger than that of said light-permeating layer through the reflecting layer.
A method of producing an optical recording medium capable of writing an information thereon and reading the information therefrom by using a laser beam, comprising the steps of:
- forming a magnetic recording film on one side surface of a substrate on which said laser beam is incident;
- and
- forming a transparent layer having a thickness not more than 0.5 mm over said magnetic recording film.
Dependencies are inferred from the claim text.