Optical information medium and evaluation method
AssigneeTDK Corporation
InventorsNaoki Hayashida, Hideki Hirata, Toshifumi Tanaka
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Abstract
An optical information medium has a light-transparent substrate and an information recording layer, wherein optical recording and/or reading is performed with a laser beam that enters the information recording layer from the light-transparent substrate side. A cured polysilazane film is disposed on the laser beam incident side of the light-transparent substrate, and the light-transparent substrate or the light-transparent substrate having the cured polysilazane film integrated thereon has a tensile modulus of at least 200 MPa. The medium on its laser beam incident side surface is improved in mar resistance.
Claims11
An optical information medium comprising a light-transparent substrate and an information recording layer, wherein optical recording and/or reading is performed with a laser beam that enters said information recording layer from the light-transparent substrate side, wherein
- said medium includes a cured polysilazane film disposed on the laser beam incident side of said light-transparent substrate, and
- said light-transparent substrate or said light-transparent substrate having the cured polysilazane film integrated thereon has a tensile modulus of at least 200 MPa.
In connection with an optical information medium comprising a light-transparent substrate and an information recording layer, wherein optical recording and/or reading is performed with a laser beam that enters said information recording layer from the light-transparent substrate side,
- a method for evaluating the optical information medium for mar resistance on its laser beam incident side surface, comprising the steps of
- intentionally abrading the laser beam incident side surface of the optical information medium,
- then measuring a recording/reading characteristic, and
- evaluating the mar resistance of the laser beam incident side surface on a basis of the measured value.
Dependencies are inferred from the claim text.