Hitachi Displays Launches 800 x 480 LCD Panel for Mobile Phone
Hitachi Displays, Ltd. started mass production of 800 x 480 2.9-inch LCD panels for use in mobile phones, which the company claims is "the industry's first 800 x 480 product as a mobile phone display panel." The users can view the entire image without side scrolling when browsing websites designed to match the size of a personal computer monitor or watching VGA (480 x 640) video. The panel employs the company's proprietary liquid crystal technology called IPS that boasts wide viewing angle and high image quality.
The pixel count is five times that of QVGA (240 x 320), which has been the norm for mobile phone panels. If the resolution of an LCD panel is boosted by simply increasing the pixel count, areas through which no light from a backlight unit can pass, e.g. wiring, will also increase. In order to boost resolution while maintaining the brightness, the luminance of the backlight unit must also be enhanced, resulting in an increase in power consumption. To solve the problem, the company has focused on the improvement of the transmittance of light from the backlight unit by revamping the pixel structure and microfabricating the wiring.
IPS LCD works differently from the general TFT LCD in that a horizontal electric field causes liquid crystal molecules to rotate in a plane parallel to the TFT substrate. This simple movement allows a wider viewing angle, better color reproduction and faster grey-to-grey response time, claims the company. The new product is a transmissive LCD panel that boasts a viewing angle of over 170 degrees in both vertical and horizontal directions, contrast ratio of about 400:1 and luminance of 250 cd/m2.