• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.3
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• pp.8-13
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• 2010

For better picture quality in LCD TVs, it is important to reach a steady emitting state within as short a time as possible in the initial stage after the TV is turned on. The initial characteristics of LCD TVs are mainly determined by the properties of the backlight. In the present study, the photometric and spectroscopic properties of a 55-inch Cold Cathode Fluorescent Lamp (CCFL) and Light Emitting Diode (LED) backlights were investigated. The measured properties include time dependence of the spectrum, luminance, and color coordinates. The results show that the change in the spectroscopic properties of the LED backlight is smaller than that of the CCFL backlight. This indicates that the initial picture quality of the LCD TV with the LED backlight is superior to that with the CCFL backlight. The origins of this difference were discussed in relation to the inherent characteristics of the two light sources.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08b
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• pp.1093-1095
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• 2007

This paper reviews the state of the art of critical processes and proposes novel structures of an integrated device comprising LCD and OLED backlight that increases the compactness and decreases the assembly time of hand-held mobile display units like the hand-sets of mobile phones

• Proceedings of the IEEK Conference
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• 2000.11b
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• pp.237-240
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• 2000

It is expected that there will be the regulation for limiting the amount of Hg content in cold cathode fluorescent lamp (CCFL) for LCD backlight system. Now it is necessary to develop mercury-free backlight system. The mercury-free CCFL coated with PDP phosphors was fabricated and evaluated. The CCFL filled with Xe and Ne showed 4500 ㏅/$m^2$ with efficiency of 13 lm/W.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.1193-1195
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• 2008

We propose a novel light guide plate for an edge-lit LED backlight. Properly designed micro-prisms enable light to go out of the LGP in near vertical direction and luminance fluctuations in front of the LEDs to be invisible.

• The Transactions of the Korean Institute of Power Electronics
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• v.13 no.2
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• pp.96-102
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• 2008

In a large screen sized LCD-TV, a backlight system with only one cold cathode fluorescent lamp(CCFL) can not meet brightness specification. Thus, considerable numbers of CCFLs are used to meet brightness specification. In this paper, the design guide for the inverter transformer which can drive 4 CCFLs instantaneously is presented. With the presented design, the inverter transformer that guarantee identical lamp currents under the nonidentical lamp characteristic condition, can be implemented easily. The developed inverter transformer is adopted in a 42" LCD-TV backlight. The experimental results are presented to show the validity of the presented design guide.

• Journal of the Microelectronics and Packaging Society
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• v.11 no.2 s.31
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• pp.37-41
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• 2004

Parallel combination of cold chathode fluorescent lamps (CCFL) are widely used as the light sources of LCD TV backlight. Brightness uniformity is safisfied by using one transformer per one CCFL. Instead of using one transformer per oneCCFL, one transformer is used to drive 8 CCFLs by using differential driving method. A differential driving inverter with two transformers is developed to drive 16 CCFLs of 26' backlight for LCD TV. The brightness uniformity of $88\%$ was obtained by driving 26' backlight with the developed differential driving inverter successfully.

• Proceedings of the Optical Society of Korea Conference
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• 2006.02a
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• pp.199-200
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• 2006

• Journal of Information Display
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• v.10 no.4
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• pp.164-170
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• 2009

The dependences of color gamut size and power consumption on the area ratio of the neutral and green subpixels for the RGB-LED-backlight RGBW LCD were studied, in which the red- and blue-subpixel areas are the same and represent one-quarter of the pixel aperture area. It was found that the color saturation of the RGBW LCD can be improved through the use of a smaller neutral- and green-subpixel area ratio, at the expense of higher power consumption.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.1450-1452
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• 2009

In this work, a plastic diffuser which has a surface similar to Sinusoidal wave profile for application of LC D backlighting is proposed. This new pattern diffuser is achieved the values of the transmission efficiency an d diffusion efficiency all over 70%, and it also has the value about gain over 1.1. Additionally, this new patter n diffuser has high uniformity when we put it in the LCD backlight module and its thickness is only 2mm. With these foregoing properties, this diffuser film can widely applied to LCD displays systems etc.

• Journal of Information Display
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• v.5 no.2
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• pp.6-9
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• 2004

We have developed the Scan-backlight Stereoscopic LCD that is a kind of field-sequential -Stereoscopic LCD combining the Dual- Directional- Backlight and the fast-response OCB panel. The Dual-Directional-Backlight using a double-sided prism sheet can change the direction of light by switching the LED light sources. The OCB panel using Feed-Forward Drive can realize frame rate of 120 Hz. As a result, the Scan-backlight Stereoscopic display works at its original resolving power, and produces flicker-free stereoscopic images. This auto- stereoscopic display can resolved the problems of the double images and the pseudoscopic images in case of watching at oblique angles.