US4129802A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low-pressure mercury vapor discharge lamp
Assignee: US Philips Corp
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Filing: 1977-09-06
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Granted: 1978-12-12
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Expires: 1997-09-06
Abstract
Abstract A low-pressure mercury vapor discharge lamp having an internal transmissive starting strip with two separate parts. The separation between the parts is bridged by a narrow straight or helix-shaped conductive connecting strip to bring the total resistance of the starting strip to a value between 50,000 and 150,000 ohms.
Inventors
- 👤 Louis E. Vrenken
- 👤 Franciscus M. P. Oostvogels
- 👤 Rein W. VAN DER Wolf
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 04:56
CPC Classifications
H; H01; H01J; H01J61/00; H01J61/02; H01J61/54; H01J61/545
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
121 words
A tubular low-pressure mercury vapor discharge lamp which comprises a discharge tube, first and second electrodes disposed within said discharge tube in spaced relationship, a light-transmissive conductive coating disposed on the interior of said discharge tube and not connected to either electrode, and a luminescent layer disposed on at least a portion of the inner surface of said discharge tube, said conductive coating consisting of at least two parts which are axially spaced and which each have a resistance per square between 400 and 4000 ohm, said parts being connected to each axially adjacent part by at least one electrical conductor having such a resistance that the total series resistance of the entire conductive coating is between 5000 and 500,000 ohms.
Claim 2
Dependent Claim
121 words
A tubular low-pressure mercury vapor discharge lamp which comprises a discharge tube, first and second electrodes disposed within said discharge tube in spaced relationship, a light-transmissive conductive coating disposed on the interior of said discharge tube and not connected to either electrode, and a luminescent layer disposed on at least a portion of the inner surface of said discharge tube, said conductive coating consisting of at least two parts which are axially spaced and which each have a resistance per square between 400 and 4000 ohm, said parts being connected to each axially adjacent part by at least one electrical conductor having such a resistance that the total series resistance of the entire conductive coating is between 5000 and 500,000 ohms.
Claim 3
Dependent Claim
37 words
A low-pressure vapor discharge lamp as claimed in claim 1 wherein said electrical conductor consists of the same material as said parts of the light-transmissive conductive coating but has a higher resistance per square than said parts.
Claim 4
Dependent Claim
49 words
A low-pressure mercury vapor discharge lamp as claimed in claim 1 wherein said connecting conductor consists of the same material and has a similar resistance per square as the parts of the conductive coating and is suitably dimensioned to produce the total resistance of between 5000 and 500,000 ohms.
Claim 5
Dependent Claim
32 words
A low-pressure mercury vapor discharge lamp as claimed in claim 1 wherein said connecting conductor consists of at least one connecting strip, extending approximately parallel to the longitudinal axis of the lamp.
Claim 6
Dependent Claim
17 words
A low-pressure mercury vapor discharge lamp as claimed in claim 1 wherein said connecting conductor is helical.
References Cited (Backward Citations)
US1984428A
Cited
US2491854A
Cited
US2733371A
Cited
US3411947A
Cited
US3772631A
Cited
US3947801A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-12-11 | 1982-06-12 | 1982-12-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-12-11 | 1986-06-12 | 1986-12-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-12-11 | 1990-06-12 | 1990-12-12 | $7700.00 | Window Closed / Lapsed |