US4127789A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Light-pervious, heat-reflecting filter and electric lamps having such a filter
Assignee: US Philips Corp
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Filing: 1977-10-27
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Granted: 1978-11-28
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Expires: 1997-10-27
Abstract
Abstract The life of light-pervious, thermal radiation-reflecting filters of tin-doped indium oxide is drastically elongated when used in oxidizing or reducing medium by coating the indium oxide layer with pyrolytic or hydrolytic silicon dioxide.
Inventors
- 👤 Heiner Kostlin
- 👤 Rudiger Jost
- 👤 Hans Auding
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 09:49
CPC Classifications
G; G02; G02B; G02B5/00; G02B5/20; G02B5/208; H; H01; H01J; H01J61/00; H01J61/02; H01J61/30; H01J61/34; H01J61/38; H01J61/40
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
44 words
A light-pervious, thermal radiation-reflecting filter having a light-pervious substrate coated with tin-doped indium oxide, characterized in that on its side remote from the substrate the filter is coated with silicon dioxide selected from the group consisting of hydrolytic silicon dioxide and pyrolytic silicon dioxide.
Claim 2
Dependent Claim
44 words
A light-pervious, thermal radiation-reflecting filter having a light-pervious substrate coated with tin-doped indium oxide, characterized in that on its side remote from the substrate the filter is coated with silicon dioxide selected from the group consisting of hydrolytic silicon dioxide and pyrolytic silicon dioxide.
Claim 3
Dependent Claim
72 words
An electric lamp having a light-pervious lamp envelope in which an electric element is arranged, having current supply wires to the electric element which are passed in a vacuum-tight manner through the wall of the lamp envelope, the lamp envelope having a tin-doped indium oxide layer, characterized in that the tin-doped indium oxide layer is coated with silicon dioxide selected from the group consisting of hydrolytic silicon dioxide and pyrolytic silicon dioxide.
Claim 4
Dependent Claim
72 words
An electric lamp having a light-pervious lamp envelope in which an electric element is arranged, having current supply wires to the electric element which are passed in a vacuum-tight manner through the wall of the lamp envelope, the lamp envelope having a tin-doped indium oxide layer, characterized in that the tin-doped indium oxide layer is coated with silicon dioxide selected from the group consisting of hydrolytic silicon dioxide and pyrolytic silicon dioxide.
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) | 1981-11-27 | 1982-05-29 | 1982-11-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-11-27 | 1986-05-29 | 1986-11-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-11-27 | 1990-05-29 | 1990-11-28 | $7700.00 | Window Closed / Lapsed |