• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.769-772
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• 2008

For several years, many researchers have proposed LED backlight dimming technology for low power consumption and high contrast ratio. One of the major issues plaguing RGB LED with 2D dimming technology is color shift. This undesirable variation makes it difficult to use RGB LED as light sources in the backlight system. This paper describes the useful method of the optical feedback system for 2D dimming RGB LED backlight. The test results show that our proposed method is very suitable for the 2D dimming technology.

• Journal of Information Display
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• v.11 no.2
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• pp.45-48
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• 2010

A direct-lit liquid crystal display that does not use color filters is proposed. A backlight unit that employs compartmentalized RGB LED and lenticular-lens arrays is used instead of color filters to direct the RGB LED lights into the RGB subpixels. The color-filterless LED backlight design, simulation, and experiment results are presented.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.76-78
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• 2009

A liquid crystal display that does not use color filters is proposed. A backlight unit that employs compartmentalized RGB LED arrays and a lenticular lens array is used instead of the color filters in order to direct RGB LED lights into the RGB subpixels. A design of color-filterless LED backlight and experimental results are presented.

• Proceedings of the KIPE Conference
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• 2007.07a
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• pp.244-246
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• 2007

The LCD backlight technique using light-emitting diode(LED) has been studied in the recent backlight market. The white light is need for LCD backlight and it is generally implemented by combining the RGB-LEDs to obtain the high brightness. However, RGB-LEDs have different color characteristics for the current and temperature variations, which results in the color shift problem. The color shift characteristics of RGB-LEDs for the current and temperature variations are investigated in this paper. This result can be used to control the color of backlight system using RGB-LEDs.

• 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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• 2006.08a
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• pp.1086-1089
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• 2006

We have developed 2.4" QVGA wide color gamut LCD module using RGB-LED backlight. The color gamut is achieved 100% of NTSC compared to 70% of NTSC when used with White-LED backlight. But RGB LED backlight is difficult to maintain its color balance since RGB LED is gradually degraded by the change of ambient temperature and a long term aging characteristic, etc. This paper describes a feasibility study of our optical feedback system developed for preventing such a color shift.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.375-376
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• 2007

In this work, we have simulated a 42-inch LED BLU which was based on 300 RGB LEDs. We have done an adjustment of LEDs' strip distance and a height of the top of the LED to the back of the LCD to get white color uniformity. So, we have changed simultaneously the distance between the top of the LEDs and the back of the LCD. Moreover, we set a fixed position for the horizontal of LED's pitch. And then, we have experimented and compared to our simulation data.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.1073-1076
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• 2009

The dependences of color gamut size and power consumption on the area ratio of neutral and green sub-pixels for the RGBW LCD with RGB LED backlit are studied, in which the areas of red and blue sub-pixels are the same and are one quarter of pixel apertu re area. It is found that high color saturation and power saving can be achieved for the proposed RGBW LCD.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.1153-1155
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• 2008

Color dimming technology has been developed for high color gamut and aggressive power saving. In our new algorithm, we proposed a new concept of 'color class', with which it is possible to control RGB color luminance effectively and exactly. We reached color gamut of 155% of NTSC 1976 and reduced power consumption under 100 watt for 46 inch LCD.

• Proceedings of the KIPE Conference
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• 2008.06a
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• pp.335-337
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• 2008

In this paper, an X-Y channel dimming light emitting diode (LED) backlight with temperature compensation for in LCD TVs is proposed. It shows local dimming effects such as reduced power consumption and high dynamic contrast ratio even with much less number of LED drivers than that of the conventional two-dimensional local dimming method. Moreover, the image distortion caused by temperature variation of LED block can be effectively compensated. The validity of the proposed dimming method is verified by simulation and experimental results based on a RGB-LED backlight of a 32-inch LCD TV.