Optical information recording material and method of recording and reproducing information using same material
AssigneeMatsushita Electric Industrial Co., Ltd.
InventorsTakeo Ohta, Nobuo Akahira, Tatsushi Nakamura, Tadaoki Yamashita
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Abstract
An optical information recording material comprising a thin film of a suboxide of a metal or semimetal of Group IIIB, IVB, VB or VIB, e.g. TeO.sub.x where x<2.0 or BiO.sub.x where x<1.5, added with up to 50 mole % of S and/or Se. When irradiated with light of relatively low energy density, the thin film exhibits such changes in optical density that information can be optically recorded on this material with high contrast ratio. Recorded information can be reproduced by either transmitted light or reflected light and, when desired, can be erased by light irradiation of adequate energy density.
Claims13
An optical information recording material comprising, as a photosensitive material which exhibits a change in optical density when optical energy is applied thereto, at least one suboxide of a metal or semimetal selected from the elements of Groups IIIB, IVB, VB and VIB added with at least one Group VIB element selected from the group consisting of S and Se.
In a method of optically recording and reproducing information, wherein information is recorded on a thin film of a photosensitive material by applying optical energy to the thin film to cause a selective change in optical density of the thin film and subsequently reproduced by applying optical energy to the thin film to detect variations of optical density of the thin film resulting from the recording of information,
- the improvement comprising said photosensitive material being at least one suboxide of a metal or semimetal selected from the elements of Groups IIIB, IVB, VB and VIB and added with at least one Group VIB element selected from the group consisting of S aand Se.
Dependencies are inferred from the claim text.