IP Library Granted Patent US 7,489,091
Granted Patent B2
US 7,489,091 · App. 11/165,464 · Granted Feb 10, 2009

Backlight unit for liquid crystal display device

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Quick Facts
Patent No.
US 7,489,091
App. No.
11/165,464
Granted
Feb 10, 2009
Kind
B2
Abstract

A backlight unit includes: a plurality of cold cathode fluorescent lamps; a plurality of capacitors respectively connected to both ends of each of the cold cathode fluorescent lamps, the capacitors having respective impedance that are selected to allow the same amount of current to flow through each of the plurality of the cold cathode fluorescent lamps; and an inverter connected to the capacitors of the cold cathode fluorescent lamps.

Claims (8)

1. A liquid crystal display device comprising:

a liquid crystal display panel driven in a vertically upright orientation;

a plurality of cold cathode fluorescent lamps for emitting light to the liquid crystal display panel connected to one another in parallel;

a plurality of high voltage capacitors respectively connected to both ends of each of the plurality of cold cathode fluorescent lamps to form qualitatively similar equivalent circuits as the external electrode fluorescent lamps; and

a lamp housing positioned under the plurality of cold cathode fluorescent lamps and encompassing the plurality of cold cathode fluorescent lamps,

wherein a pair of capacitors with capacitances different from those of the others of the plurality of capacitors are connected to both ends of a lowermost cold cathode fluorescent lamp arranged at a side of the lamp housing.

2. The device of claim 1 , wherein the others of the plurality of capacitors are connected to both ends of each of the others of the plurality of cold cathode fluorescent lamps.

3. The device of claim 1 , wherein the plurality of cold cathode fluorescent lamps are connected in parallel through the plurality of capacitors connected to both ends of each of the plurality of cold cathode fluorescent lamps.

Assignments (2)
CHANGE OF NAME Recorded Oct 17, 2008
From: LG.PHILIPS LCD CO., LTD.
To: LG DISPLAY CO., LTD.
Reel/Frame 021754/0045 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jun 24, 2005
From: KIM, PU JIN; LEE, JAE HO; LEE, YONG KON
To: LG.PHILIPS LCD CO., LTD.
Reel/Frame 016730/0592 →