• Journal of the Optical Society of Korea
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• v.12 no.3
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• pp.174-177
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• 2008

The luminance properties of FFL(Flat Fluorescent Lamp) backlights have been investigated in detail for the first time. The on-axis luminance gain as well as viewing-angle characteristics on various combinations of optical films were obtained from FFL backlight and compared to the results of conventional CCFL(cold-cathode fluorescent lamps) backlights. It was found that the on-axis luminance gains achieved by using optical films in the FFL backlight were lower than those in the CCFL backlight indicating that the recycling processes occurring between optical films and light sources/reflection sheet are not so effective in the FFL backlight due to the much larger area of, and thus higher absorption probability of the FFL. This result suggests that new optical films should be developed for FFL backlight and other flat-lamp backlight technologies.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.21 no.7
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• pp.6-12
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• 2007

A flat fluorescent lamp (FFL) developed as a light source for LCD TV backlight was used as a light source for general lighting application and its electro-optical characteristics were measured and evaluated. The channels of FFL were formed from a flat glass at high temperature by using a mold. The performance of FFL with lighting future was shown to improve by optimizing the channel profile of FFL. In this paper, the brightness efficiency of FFL with lighting fixture was evaluated and compared with that of the hot cathode fluorescent lamp (HCFL), the major light source for general lighting. The optical efficiency of FFL with future was shown to be 72.7[1m/W].

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.1725-1728
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• 2006

Flat fluorescent lamp(FFL) is used as a light source for LCD TV backlight and is composed of many discharge channels but each channel may not be turned on simultatneouly especially at cold temperature. The simultaneous start of each lamp channels of FFL was accomplished by driving FFL with specially designed voltage and currnet waveforms without sacrificing the inverter efficency.

• 전자공학회논문지 IE
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• v.44 no.1
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• pp.1-5
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• 2007

This experiment was analysed the discharge characteristics of FFL(flat fluorescent lamp). FFL is operated by sine and pulse wave source. We use FFL which has the electrodes covered with dielectric, observed the discharge characteristics of FFL by V-Q Lissajous' figure. When FFL is operated with pulsed, the discharge current flows after the applied voltage is risen. When the duty ratio increases, the number of metastable xenon atoms seem to increase. Consequently, the 172nm radiation becomes strong as the duty ratio increases.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.1330-1333
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• 2006

The channel shape of FFL(Flat Fluorescent Lamp) was designed by optical simulation. It was possible to design and manufacture the channel in any shape using glass forming. The best suitable brightness uniformity of 83.7% was achieved.

• Journal of the Semiconductor & Display Technology
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• v.8 no.2
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• pp.43-47
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• 2009

Glass forming technology is used to form channels of external electrode flat fluorescent lamps (FFL). The efficiency of FFL depends on the number and the length of the channels. Five FFLs with same size ($300\;mm{\times}80\;mm$), different channel number, and different channel length were fabricated. The electrical and optical characteristics of 5 FFLs were evaluated. It was found that the FFL with one channel with its channel length of 1,110 mm and channel width of 7 mm corner width was shown to have the highest efficiency at room temperature operation.

• Journal of the Microelectronics and Packaging Society
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• v.14 no.2 s.43
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• pp.1-8
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• 2007

A flat fluorescent lamp (FFL) was developed as a light source for LCD TV Backlight. The channels of FFL were realized by forming the flat glass at high temperature. The performance of the backlight with FFL was shown to improve by optimizing the FFL channel profile that has elliptical shape, 4.4 mm height and 1.4 mm sealing distance. In this paper, the brightness uniformity of LCD TV backlights was investigated by optical simulation of FFL channel profiles. The brightness of LCD TV using FFL with the optimized channel profile was shown to be $576\;cd/m^2$.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.1067-1068
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• 2008

An inverter for driving flat fluorescent lamp(FFL) with various protection circuits using micro controller(Micom) is proposed in this paper. The inverter will be shut down if the fault operating conditions such as open lamp, over current and over voltage are detected.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.12
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• pp.1105-1110
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• 2008

In this study, plasma flat fluorescent lamps (FFLs) having two electrode type structures of surface discharge was fabricated by screen printing and were characterized using spectra-radiometer and square pulse power supply. Two types of FFLs (cross-type and line-type electrode structure) were compared with variation of discharge shape and electrode distance.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.687-690
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• 2009

It has been recently reported that nano-sized MgO single crystal powders emit ultraviolet by stimulation of electrons under vacuum condition. Therefore, in this study, nano-crystalline MgO powders were applied to a xenon plasma flat fluorescent lamp for LCD backlight to improve emission efficiency of the lamp by help of extra ultraviolet from nano-MgO. For comparison with nano-crystalline MgO powders, MgO nano-thin film was applied directly on phosphors inside a lamp panel through e-beam evaporation The luminance and efficiency of FFL with an addition of MgO nano-crystal powders on phosphors were improved by around 20%. Application of MgO thin film to phosphors worsened the emission characteristics of FFLs, even rather than FFL without MgO. The reason came from insufficient stimulation of phosphors by UV, crystallinity of MgO, and low secondary electron coefficient.