US3707642A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Vapor lamp which incorporates a special phosphor coating
Assignee: Philips North America LLC
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Filing: 1970-08-31
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Granted: 1972-12-26
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Expires: 1990-08-31
Abstract
Abstract Fluorescent lamp incorporates a finely divided phosphor coating of different particle sizes. The phosphor particles of the coating which are positioned next to the envelope inner surface are preferably relatively fine and are smaller than the relatively coarse particles which are positioned farther from the envelope inner surface. Such a special phosphor coating enables the total amount of coated phosphor to be considerably reduced.
Inventors
- 👤 William A Thornton Jr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 12:08
CPC Classifications
C; C09; C09K; C09K11/00; C09K11/02; H; H01; H01J; H01J61/00; H01J61/02; H01J61/38; H01J61/42; H01J61/48
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
73 words
The device as specified in claim 1, wherein said phosphor coating is carried on the inner surface of said envelope in at least two discrete layers, the particles comprising the layer which is positioned closer to said envelope inner surface having an ultraviolet radiation reflectivity of at least about 0.2, and the particles comprising the layer which is positioned farther from said envelope having an ultraviolet radiation reflectivity of less than about 0.1.
Claim 2
Dependent Claim
141 words
A fluorescent lamp comprising: a. an elongated light-transmiTting envelope having electrodes operatively disposed proximate the ends thereof and enclosing a small charge of mercury and inert ionizable starting gas, and a low-pressure ultraviolet-generating discharge adapted to be sustained between said electrodes during operation of said lamp; and b. a halophosphate phosphor coating carried on the inner surface of said envelope, said phosphor coating comprising individual particles of different average particle size, the portion of said phosphor coating which is positioned nearest to the inner surface of said envelope, and thus farthest from said operating discharge, having an average particle size not exceeding about 3 microns, and the portion of said phosphor coating which is positioned farthest from the inner surface of said envelope, and thus closest to said operating discharge, having an average particle size of at least about 6 microns.
Claim 3
Dependent Claim
58 words
The lamp as specified in claim 3, wherein said phosphor coating is carried on the inner surface of said envelope in at least two discrete layers, and any said layer, which is positioned closer to the inner surface of said envelope than an adjacent layer, having a smaller particle size than the particle size of said adjacent layer.
Claim 4
Dependent Claim
61 words
The lamp as specified in claim 3, wherein said phosphor is present in two discrete layers, said layer which is adjacent the inner surface of said envelope having a particle size of from about 0.1 to 3 microns, and said layer which is farthest from the inner surface of said envelope having a particle size of about 6 to 35 microns.
Claim 5
Dependent Claim
60 words
The lamp as specified in claim 5, wherein said layer which is closest to the inner surface of said envelope has a coating weight of from 0.2 to 2 mg/cm2 of coated halophosphate, and said layer which is farthest from the inner surface of said envelope has a coating weight of from 0.5 to 2 mg/cm2 of coated bulb surface.
Claim 6
Dependent Claim
61 words
The lamp as specified in claim 6, wherein said layer which is closest to the inner surface of said envelope has a coating weight of from 0.8 to 1.4 mg/cm2 of coated bulb surface, and said layer which is farthest from the inner surface of said envelope has a coating weight of from 1.3 to 1.8 mg/cm2 of coated bulb surface.
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) | 1975-12-26 | 1976-06-26 | 1976-12-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-12-26 | 1980-06-26 | 1980-12-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-12-26 | 1984-06-26 | 1984-12-26 | $7700.00 | Window Closed / Lapsed |