Patent US4499397A successfully refreshed from Google Patents.
US4499397A
Expired / Lapsed
US
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Color corrective coating for arc lamp
Assignee: General Electric Co
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Filing: 1982-11-05
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Granted: 1985-02-12
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Expires: 2002-11-05
Abstract
Abstract An arc lamp having a coating comprised of an inorganic yellow pigment plus white pigments located on the inner surface of its outer glass envelope is disclosed. The coating is a color corrective diffuse type which improves the color rendition of the lamp by altering the portion of visible light radiation of the blue spectrum relative to that of the yellow portion of the light spectrum.
Inventors
- 👤 William G. James
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 10:24
CPC Classifications
H; H01; H01J; H01J61/00; H01J61/02; H01J61/38; H01J61/40
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
113 words
An arc lamp having an inner envelope of a quartz type arc tube containing a mercury vapor or other metallic vapors, an inner tungsten filament light source, means to produce an electrical discharge, and an outer envelope having a color corrective coating on its inner surface; said color corrective coating effective for shifting the color point on a MacAdam type color plot of an arc tube lamp from approximately x=0.4, y=0.365 and CCT=3400° C. to approximately x=0.435, y=0.405 and CCT=3000° C., which is substantially a color point of an incandescent lamp having a tungsten type filament, wherein said color corrective coating comprises: a mix of electrostatic silica blend and a yellow oxide pigment.
Claim 2
Dependent Claim
113 words
An arc lamp having an inner envelope of a quartz type arc tube containing a mercury vapor or other metallic vapors, an inner tungsten filament light source, means to produce an electrical discharge, and an outer envelope having a color corrective coating on its inner surface; said color corrective coating effective for shifting the color point on a MacAdam type color plot of an arc tube lamp from approximately x=0.4, y=0.365 and CCT=3400° C. to approximately x=0.435, y=0.405 and CCT=3000° C., which is substantially a color point of an incandescent lamp having a tungsten type filament, wherein said color corrective coating comprises: a mix of electrostatic silica blend and a yellow oxide pigment.
Claim 3
Dependent Claim
113 words
An arc lamp having an inner envelope of a quartz type arc tube containing a mercury vapor or other metallic vapors, an inner tungsten filament light source, means to produce an electrical discharge, and an outer envelope having a color corrective coating on its inner surface; said color corrective coating effective for shifting the color point on a MacAdam type color plot of an arc tube lamp from approximately X=0.4, y=0.365 and CCT=3400° C. to approximately x=0.435, y=0.405 and CCT=3000° C., which is substantially a color point of an incandescent lamp having a tungsten type filament, and said color corrective coating comprises: a mix of electrostatic silica blend and a cadmium sulfide pigment.
Claim 4
Dependent Claim
113 words
An arc lamp having an inner envelope of a quartz type arc tube containing a mercury vapor or other metallic vapors, an inner tungsten filament light source, means to produce an electrical discharge, and an outer envelope having a color corrective coating on its inner surface; said color corrective coating effective for shifting the color point on a MacAdam type color plot of an arc tube lamp from approximately X=0.4, y=0.365 and CCT=3400° C. to approximately x=0.435, y=0.405 and CCT=3000° C., which is substantially a color point of an incandescent lamp having a tungsten type filament, and said color corrective coating comprises: a mix of electrostatic silica blend and a cadmium sulfide pigment.
Claim 5
Dependent Claim
34 words
An arc lamp according to claim 1 wherein said mix of electrostatic silica blend and yellow oxide pigment has portions by weight within the ranges of 95 to 99 and 5 to 1 respectively.
Claim 6
Dependent Claim
34 words
An arc lamp according to claim 2 wherein said mix of electrostatic silica blend and cadmium sulfide pigment has portions by weight within the ranges of 99.95 to 99.75 and 0.05 to 0.25 respectively.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-02-12 | 1988-08-13 | 1989-02-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-02-12 | 1992-08-13 | 1993-02-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-02-12 | 1996-08-13 | 1997-02-12 | $7700.00 | Window Closed / Lapsed |