04739227 is referenced by 24 patents and cites 3 patents.

A fluorescent lamp has an envelope tube forming a gas-tight enclosure about a pair of externally-energizable filaments which generate a plasma discharge for conversion to visible light; a keep-alive electrode is located adjacent to at least one filament. A dimming control circuit individually externally energizes each keep-alive electrode to generate an auxiliary discharge, between that keep-alive electrode and the adjacent filament, at a magnitude sufficient to maintain the adjacent filament in the spot mode of operation even if the main plasma discharge current is varied over a range sufficient to change the visible light output of the lamp over at least a 10:1 range.

Title
Fluorescent lamp dimming over large light output range
Application Number
6/911854
Publication Number
4739227
Application Date
September 26, 1986
Publication Date
April 19, 1988
Inventor
John M Anderson
Scotia
NY, US
Agent
Marvin Snyder
James C Davis Jr
Geoffrey H Krauss
Assignee
General Electric Company
NY, US
IPC
H05B 41/24
H05B 37/00
H05B 41/29
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