US4731780A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical recording element
Assignee: US Philips Corp
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Filing: 1987-01-21
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Granted: 1988-03-15
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Expires: 2007-01-21
Abstract
Abstract An optical recording element comprising an assembly of two parallel substrate plates made from a transparent synthetic resin and each comprising on their facing sides a recording layer which comprises a guide track in the form of a spiral-like groove, and a foil of sythetic resin which with both major surfaces engages or substantially engages the ridges of the recording layers present between the groove turns.
Inventors
- 👤 Petrus J. Kivits
- 👤 Martinus M. Sens
- 👤 Rene Dufour
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 14:34
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/24; G11B7/24015
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
170 words
An optical recording element comprising an assembly of two parallel substrate plates, each of said plates being made of a transparent synthetic resin and each of said plates comprising on their mutually opposing surfaces a guide track provided with a spiral-like groove and ridges between the turns of said groove, and a recording layer, situated upon and following the contours of said guide track and a slot-shaped gap present between said recording layers, characterized in that a foil of a synthetic resin is present in said gap, is sandwiched between said recording layers and engages essentially only the portions of the recording layers present on said ridges, said foil, when adhering to said recording layers, adheres only at the areas of said recording layers not in contact with said guide tracks and that said recording element is capable of recording information by radiation of said recording layers with modulated laser light through said substrate plates thereby to form in the resultant exposed areas of said recording layers light detectable changes.
Claim 2
Dependent Claim
170 words
An optical recording element comprising an assembly of two parallel substrate plates, each of said plates being made of a transparent synthetic resin and each of said plates comprising on their mutually opposing surfaces a guide track provided with a spiral-like groove and ridges between the turns of said groove, and a recording layer, situated upon and following the contours of said guide track and a slot-shaped gap present between said recording layers, characterized in that a foil of a synthetic resin is present in said gap, is sandwiched between said recording layers and engages essentially only the portions of the recording layers present on said ridges, said foil, when adhering to said recording layers, adheres only at the areas of said recording layers not in contact with said guide tracks and that said recording element is capable of recording information by radiation of said recording layers with modulated laser light through said substrate plates thereby to form in the resultant exposed areas of said recording layers light detectable changes.
Claim 3
Dependent Claim
22 words
An optical recording element as claimed in claim 1, characterized in that a foil is used which is metallized on both surfaces.
Claim 4
Dependent Claim
43 words
An optical recording element as claimed in claim 1, characterized in that the foil is connected to the substrate plates present on each side on the outer edge and/or in the central part by means of a glued joint or a welded joint.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-03-15 | 1991-09-14 | 1992-03-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-03-15 | 1995-09-14 | 1996-03-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-03-15 | 1999-09-14 | 2000-03-15 | $7700.00 | Window Closed / Lapsed |