US4227113A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Incandescent electric lamp with partial light transmitting coating
Assignee: Duro Test Corp
•
Filing: 1978-10-18
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Granted: 1980-10-07
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Expires: 1998-10-18
Abstract
Abstract An incandescent lamp of a type in which infrared (IR) energy is to be reflected back to the filament. The lamp has one section which is coated with an IR reflecting material which also will transmit visible light and another section coated with material which has a high reflectivity to IR energy and a low transmissivity to visible light. The filament is mounted off-center of the optical image axis of the envelope and substantially all of the energy in the visible light range exits from the envelope in no more than two passes.
Inventors
- 👤 Peter Walsh
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 20:26
CPC Classifications
H; H01; H01K; H01K1/00; H01K1/18; H01K1/28; H01K1/32; H01K1/325
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
204 words
An incandescent electric lamp comprising: an envelope, a filament within said envelope, means for supplying electrical current to said filament to cause it to incandesce and produce energy in both the infrared and visible ranges, the major portion of said envelope being curved and having an optical image axis for said filament, a first coating on a first part of said major portion of said envelope for reflecting the major portion of both the infrared and the visible energy from the filament incident thereon, a second coating on a substantial portion of the remaining part of said major portion of said envelope for reflecting the major portion of the infrared energy from the filament incident thereon and for transmitting therethrough the major portion of the visible energy from the filament incident thereon, said filament being mounted off of said optical image axis, said coatings on said major portion of the envelope both reflecting incident infrared energy back toward said filament, and said first and second coatings being located with respect to said major portion of said envelope so that the infrared energy which is incident thereon and which is reflected is reflected back to impinge upon said filament after two reflections from said coatings.
Claim 2
Dependent Claim
204 words
An incandescent electric lamp comprising: an envelope, a filament within said envelope, means for supplying electrical current to said filament to cause it to incandesce and produce energy in both the infrared and visible ranges, the major portion of said envelope being curved and having an optical image axis for said filament, a first coating on a first part of said major portion of said envelope for reflecting the major portion of both the infrared and the visible energy from the filament incident thereon, a second coating on a substantial portion of the remaining part of said major portion of said envelope for reflecting the major portion of the infrared energy from the filament incident thereon and for transmitting therethrough the major portion of the visible energy from the filament incident thereon, said filament being mounted off of said optical image axis, said coatings on said major portion of the envelope both reflecting incident infrared energy back toward said filament, and said first and second coatings being located with respect to said major portion of said envelope so that the infrared energy which is incident thereon and which is reflected is reflected back to impinge upon said filament after two reflections from said coatings.
Claim 3
Dependent Claim
31 words
An incandescent electric lamp as in claim 1 wherein the first and second coatings each occupy up to about 50% of the surface area of said major portion of said envelope.
Claim 4
Dependent Claim
45 words
An incandescent electric lamp as in claim 2 wherein the lamp further includes a base portion, one of said first and second coatings located on the top portion of the envelope opposite the base and the other located on the bottom portion adjacent the base.
Claim 5
Dependent Claim
29 words
An incandescent electric lamp as in claim 2 wherein the first and second coatings each occupy a respective part of the envelope which extends generally vertically of the base.
Claim 6
Dependent Claim
15 words
An incandescent electric lamp as in claim 1 wherein said first coating comprises a metal.
Claim 7
Dependent Claim
27 words
An incandescent electric lamp as in claim 5 wherein said first coating is of a metal selected from the group consisting of silver, gold, copper and aluminum.
Claim 8
Dependent Claim
26 words
An incandescent electric lamp as in claim 5 wherein said first coating is of a metal selected from the group consisting of lithium, sodium and potassium.
Claim 9
Dependent Claim
13 words
An incandescent electric lamp as in claim 6 wherein the metal is silver.
Claim 10
Dependent Claim
52 words
An incandescent electric lamp as in claim 6 wherein the second coating is of a discrete layer of a metal and a discrete layer of a dielectric film the real part of whose index of refraction of visible light energy matches the imaginary part of the index of refraction of the metal.
Claim 11
Dependent Claim
52 words
An incandescent electric lamp as in claim 8 wherein the second coating is of a discrete layer of a metal and a discrete layer of a dielectric film the real part of whose index of refraction to visible light energy matches the imaginary part of the index of refraction of the metal.
Claim 12
Dependent Claim
24 words
An incandescent electric lamp as in claim 9 wherein the second coating comprises a discrete layer of silver between two layers of a dielectric.
Claim 13
Dependent Claim
23 words
An incandescent electric lamp as in claim 7 wherein the second coating comprises a layer of a dielectric between two layers of silver.
Claim 14
Dependent Claim
21 words
An incandescent electric lamp as in claim 1 wherein said major portion of the envelope is symmetrical about said optical axis.
Claim 15
Dependent Claim
35 words
An incandescent electric lamp as in claim 1 wherein the visible range energy which is to be transmitted through said second coating is incident thereon after no more than one reflection from said first coating.
Claim 16
Dependent Claim
44 words
An incandescent electric lamp as in claim 1 wherein said coatings are placed on the major portion of the envelope such that the infrared energy has one reflection from said first coating and one reflection from said second coating before returning to said filament.
References Cited (Backward Citations)
US1342894A
Cited
US2121314A
Cited
US2144400A
Cited
US2488751A
Cited
US2622222A
Cited
US2859369A
Cited
US3209192A
Cited
US3209188A
Cited
GB1017828A
Cited
US4039878A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-10-07 | 1984-04-07 | 1984-10-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-10-07 | 1988-04-07 | 1988-10-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-10-07 | 1992-04-07 | 1992-10-07 | $7700.00 | Window Closed / Lapsed |