Four-color channel TFT-LCD developed

MAY 20--Samsung Semiconductor Inc. (San Jose, CA; www.usa.samsingsemi.com), a provider of TFT-LCD display panels, has announced the industry's first four-color-channel TFT LCD technology. Conventional LCDs use subpixels for three primary colors--red, green and blue (RGB). With a four-color channel, Samsung added a white subpixel to obtain maximum brightness.

White color is achieved by transmitting fluorescent backlight through an RGB filter. In this process, the luminance of the source light is reduced to 33%. Because Samsung's new four-color TFT-LCD has an additional white subpixel, the luminance of a backlight is preserved as it is transmitted through a clear white subpixel instead of a colored filter.

A four-color TFT-LCD increases luminance by 30-70% while consuming the same power as a conventional RGB TFT-LCD. At an equivalent luminance level, a four-color TFT-LCD consumes about 50% less power than a conventional RGB LCD.

In the past, researchers were unable to introduce a fourth subpixel to an LCD without having to decrease luminance, increase manufacturing costs, and distort color. Samsung resolves these issues by using novel pixel arrays and proprietary color processing algorithms. Sub-pixel rendering technology was adopted to generate enhanced resolution. The horizontal subpixel font rendering technology fine-tunes the vertical aspect of the pixels, optimizing smoother vertical strokes for font characters.