US3784861A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Lamp with opaque screen
Assignee: US Philips Corp
•
Filing: 1971-02-25
•
Granted: 1974-01-08
•
Expires: 1991-02-25
Abstract
Abstract A halogen incandescent lamp having on a portion of the bulb a black opaque coating of silicon and silicon dioxide.
Inventors
- 👤 V Notelteirs
- 👤 J Goorissen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 09:51
CPC Classifications
H; H01; H01K; H01K1/00; H01K1/26; H01K1/28; H01K1/32
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
11 words
A lamp according to claim 4 wherein the coating includes kaolin.
Claim 2
Dependent Claim
22 words
A lamp according to claim 1 wherein the envelope has interior and exterior surfaces, and the coating is on the exterior surface.
Claim 3
Dependent Claim
30 words
A lamp according to claim 1 wherein the envelope is a closed tubular member with an upper end part adjacent the filament, and said coating surrounds said upper end part.
Claim 4
Dependent Claim
37 words
A lamp according to claim 4 wherein the lamp has a second filament within the envelope axially spaced from the first, and a second coating axially spaced from the first and forming a band around the envelope.
References Cited (Backward Citations)
US1830165A
Cited
US1935723A
Cited
US2165987A
Cited
US2486811A
Cited
US2781654A
Cited
US2795722A
Cited
US2918595A
Cited
US3320460A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-01-07 | 1977-07-09 | 1978-01-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-07 | 1981-07-09 | 1982-01-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-07 | 1985-07-09 | 1986-01-08 | $7700.00 | Window Closed / Lapsed |