07973493 is referenced by 2 patents and cites 15 patents.

In order to enhance stability of a discharge lamp at the time of dimming lighting even in the case where a light output is lowered, a direct current superimposing circuit superimposes a direct current voltage on an alternating current voltage applied to a fluorescent lamp, and a dimming signal correction circuit receives a detection value of a direct current voltage detection circuit and a dimming signal that is from an outside, outputs a dimming signal higher in level than the dimming signal in the case where the detection value of the direct current voltage detection circuit exceeds a first threshold value, and decreases the level of the outputted dimming signal to the level of the inputted dimming signal in the case where the detection value of the direct current voltage detection circuit falls down below a second threshold value that is equal to or less than the first threshold value. Then, an amount of alternating current power supplied to the fluorescent lamp by an inverter circuit is increased and decreased in response to fluctuations of the level of the dimming signal outputted by the dimming signal correction circuit, whereby the fluorescent lamp is dimmed.

Title
Discharge lamp lighting device, and illuminating device
Application Number
12/439083
Publication Number
7973493 (B2)
Application Date
August 27, 2007
Publication Date
July 5, 2011
Inventor
Takuya Sakai
Himeji
JP
Kazuhiko Tachibana
Kakogawa
JP
Kouichi Ikegami
Himeji
JP
Keisuke Ueda
Hirakata
JP
Tetsuya Hamana
Amagasaki
JP
Naoki Onishi
Kobe
JP
Agent
Greenblum & Bernstein
Assignee
Ikeda Electric
JP
Panasonic Electric Works
JP
IPC
G05F 1/00
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