Back to results
US 5,296,783 AGranted
Dual filament lamp and drive apparatus for dimmable avionics displays
AssigneeRockwell International Corporation
InventorGregory M. Fischer
Life of this patent
Estimating the term…
Abstract
An improved dimmable dual filament fluorescent lamp including a first filament and a second filament with automatic current switching between the first element and the second element when the first element opens due to a failure and further having a separating cold cathode getter plate disposed between the first filament and the second filament.
Claims9
A dimmable fluorescent backlight for displays comprising;
- a fluorescent lamp bulb having a first end and a second end;
- disposed at said first end of said fluorescent lamp bulb is a plurality of first end filaments;
- disposed at said second end of said fluorescent lamp bulb is a plurality of second end filaments;
- first current source means for providing a current through a first one of said plurality of first end filaments;
- and,
- current switching means for isolating a second one of said plurality of first end filaments when said first one of said plurality of first end filaments is provided with said current therethrough, and further for switching said current through said second one of said plurality of first end filaments when said first one of said plurality of first end filaments fails.
3 more elements
An improved fluorescent backlight for avionics displays comprising;
- a fluorescent tube having a first filament disposed therein and a second filament disposed therein;
- and,
- a getter plate coupled with and separating said first filament and second filament.
An improved fluorescent lamp apparatus comprising;
- a primary filament having a winding primary end and a primary terminal end;
- a backup filament having a winding backup end and a backup terminal end;
- transformer means for providing current for filament power, having a winding terminal end and a winding filament end;
- said winding terminal end connected with said primary terminal end and said backup terminal end;
- said winding filament end directly connected to said winding primary end and coupled to said winding backup end through a second transformer;
- a latching means coupled with said second transformer, for switching the operation of said second transformer in response to a failure of said primary filaments;
- and,
- said latching means further providing an indication signal in response to said failure of said primary filament.
5 more elements
Dependencies are inferred from the claim text.