Patent US5500574A successfully refreshed from Google Patents.
US5500574A
Expired / Lapsed
US
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Inductively coupled substantially flat fluorescent light source
Assignee: Panasonic Electric Works Co Ltd
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Filing: 1994-09-28
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Granted: 1996-03-19
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Expires: 2014-09-28
Abstract
Abstract Electrodeless, low pressure, fluorescent discharge lamp of high aspect ratio, with a substantially flat spiral rf coil adjacent a back face (and insulated therefrom), that emits light through a front surface or selected portions under control of internal reflective and phosphor coatings placement to afford minimum resonance trapping, high efficiency and uniform illumination of high specific intensity over a selected area of the front wall.
Inventors
- 👤 Oleg Popov
- 👤 Jakob Maya
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-10 01:15
CPC Classifications
H; H01; H01J; H01J65/00; H01J65/04; H01J65/042; H01J65/048; H01J61/00; H01J61/02; H01J61/24; H01J61/26; H01J61/30; H01J61/305; H01J61/70; H01J61/72; H05; H05B; H05B41/00; H05B41/14; H05B41/24
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
99 words
A fluorescent lamp device comprising: (a) a substantially flat, vacuum fight glass vessel having an aspect ratio of greater than about 2 filled with a gas at pressure below 300 Torr and having at least a portion of its interior walls coated with Al 2 O 3 or other diffuse reflecting material and some surface portions coated with only phosphor or phosphor on top of said diffuse reflecting layer; and (b) means for providing and inductively coupling RF energy into the gas mixture to generate light efficiently, the frequency of the RF being from 30 KHz to 915 MHz.
Claim 2
Dependent Claim
99 words
A fluorescent lamp device comprising: (a) a substantially flat, vacuum fight glass vessel having an aspect ratio of greater than about 2 filled with a gas at pressure below 300 Torr and having at least a portion of its interior walls coated with Al 2 O 3 or other diffuse reflecting material and some surface portions coated with only phosphor or phosphor on top of said diffuse reflecting layer; and (b) means for providing and inductively coupling RF energy into the gas mixture to generate light efficiently, the frequency of the RF being from 30 KHz to 915 MHz.
Claim 3
Dependent Claim
42 words
A fluorescent lamp device as set forth in claim 1 wherein said vessel has a flat, back surface, and wherein said means for providing RF energy includes an energizing coil which also assuming such flat shape for efficient coupling of the energy.
Claim 4
Dependent Claim
44 words
A fluorescent lamp device as set forth in claim 1 wherein said vessel has a slightly concave back surface, and wherein said means for providing RF energy includes an energizing coil which also takes such concave back shape for efficient coupling of the energy.
Claim 5
Dependent Claim
31 words
A fluorescent lamp device as set forth in claim 1 wherein said vessel has a convex back surface, the energizing coil also assuming such shape for efficient coupling of the energy.
Claim 6
Dependent Claim
99 words
A fluorescent lamp device as set forth in claim 1 wherein said vessel has a back surface and wherein said means for providing and coupling RF energy is positioned adjacent to said back surface and has a structure which provides radially and azimuthally uniform plasma in the vessel and light in such a manner that a surface at a given distance is illuminated, said vessel having a wider range of ambient temperature for optimum performance of light output due to its intrinsically less sensitive nature to ambient temperature when compared to other electrodeless or electroded compact fluorescent light sources.
Claim 7
Dependent Claim
28 words
A fluorescent lamp device as set forth in claim 1 wherein said vessel having insulating means between the means for providing and coupling RF energy and back surface.
Claim 8
Dependent Claim
34 words
A fluorescent lamp device as set forth in claim 1 further comprising at least a portion of said interior and exterior of the vessel wall through which light emerges is free of any coating.
Claim 9
Dependent Claim
33 words
A fluorescent lamp device as defined in claim 1 wherein the relative illuminance, lux, varies from about 10.5 to 12.5 over an ambient temperature range of about 30° C. to about 65° C.
Claim 10
Dependent Claim
48 words
A fluorescent lamp device as defined in claim 1 wherein said vessel has a back surface inside said vessel coated with Al 2 O 3 or other diffuse reflecting material such that substantially all the emitted light is substantially directed in one direction through said opposing flat surface.
References Cited (Backward Citations)
US4245179A
Cited
US4266167A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-03-19 | 1999-09-18 | 2000-03-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-03-19 | 2003-09-18 | 2004-03-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-03-19 | 2007-09-18 | 2008-03-19 | $7700.00 | Window Closed / Lapsed |