EP0437223A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Optical data medium cassette
Assignee: Panasonic Holdings Corp
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Filing: 1991-01-04
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Granted: —
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Expires: 2011-01-04
Abstract
Abstract An optical data medium is disclosed from which information recorded to the surface is reproduced by focusing a laser thereon and reading the light reflected from the data surface. The medium includes a first transparent layer having a top data surface for carrying data, and a second transparent layer having a bottom data surface for carrying data. A semi-transparent layer is inserted between the first and second transparent layers. When the laser is focused on the top data surface, the data carried therein is reproduced, and when the laser is focused on the bottom data surface, the data carried therein is reproduced.
Inventors
- 👤 Michiyoshi Nagashima
- 👤 Fumiaki Ueno
- 👤 Hiroyuki Ogawa
- 👤 Toshinori Kishi
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 22:32
CPC Classifications
G; G11; G11B; G11B23/00; G11B23/02; G11B23/03; G11B23/0301; G11B23/0308; G11B7/00; G11B7/12; G11B7/135; G11B7/1365; G11B7/24; G11B7/2403; G11B7/24035; G11B7/24038; G11B7/26
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
100 words
An optical data medium from which information recorded to the surface thereof is reproduced by focusing a laser thereon and reading the light reflected from the data surface, said medium comprising: a first transparent layer having a first and second surfaces, said second surface being a first data surface carrying data; a semi-transparent layer deposited on said second surface; a second transparent layer having a third and fourth surfaces, said third surface being held in contact with said semi-transparent layer and said fourth surface being a second data surface carrying data; and a reflection layer deposited on said fourth surface.
Claim 2
Dependent Claim
17 words
An optical data medium as claimed in Claim 1, wherein said reflection layer is a non-transparent layer.
Claim 3
Dependent Claim
17 words
An optical data medium as claimed in Claim 1, wherein said reflection layer is a semi-transparent layer.
Claim 4
Dependent Claim
18 words
An optical data medium as claimed in Claim 1, further comprising a protection layer on said reflection layer.
Claim 5
Dependent Claim
19 words
An optical data medium as claimed in Claim 1, wherein said first data surface is for a read-only data.
Claim 6
Dependent Claim
19 words
An optical data medium as claimed in Claim 1, wherein said second data surface is for a read-only data.
Claim 7
Dependent Claim
19 words
An optical data medium as claimed in Claim 1, wherein said second data surface is for a read/writable data.
Claim 8
Independent Claim
111 words
A method for manufacture an optical data medium from which information recorded to the surface thereof is reproduced by focusing a laser thereon and reading the light reflected from the data surface, said method comprising the steps of: forming a first transparent layer having a first and second surfaces, said second surface being a first data surface carrying data; forming a semi-transparent layer deposited on said second surface; forming a second transparent layer having a third and fourth surfaces, said third surface being held in contact with said semi-transparent layer and said fourth surface being a second data surface carrying data; and forming a reflection layer deposited on said fourth surface.
Claim 9
Dependent Claim
18 words
A method as claimed in Claim 1, wherein said second transparent layer is formed by UV curing method.
Claim 10
Dependent Claim
38 words
A cassette case for an optical data medium comprising: a casing for accommodating an optical data medium; a shutter movably mounted on said casing and having a first window; and a transparent plate mounted in said first window.
Claim 11
Dependent Claim
18 words
A cassette case as claimed in Claim 10, wherein said shutter is further formed with a second window.
References Cited (Backward Citations)
No citation records indexed.
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