Sharp Begins to Roll Out IGZO TFT-based LCD Panel (page 2)

Apr 15, 2012
Shinya Saeki, Nikkei Electronics

With those characteristics, IGZO TFT-based LCD panels can realize (1) higher resolution, (2) lower power consumption and (3) higher performance of touch panel, compared with amorphous TFT-based LCD panels, Sharp said.

Higher resolution

As for the higher resolution, because of the high carrier mobility of the panel, it is possible to reduce TFT size by about 75%, compared with the size of an amorphous Si TFT, the company said. In addition, by using a technique to reduce the thickness of gate/source lines, it becomes possible to double resolution without lowering transmittance, the company said.

Lower power consumption

In regard to the lower power consumption, the smaller TFT size enables to increase the use efficiency of backlight. Moreover, because of the low off-leak current, it became possible to maintain the orientation control of liquid crystal molecules even when drive frequency is reduced from 30-50Hz, which is common, to 2-5Hz.

When displayed data is not being changed much (e.g. when a standby screen or a photo is displayed), it is possible to stop driving TFTs for some time, and, therefore, the power consumption of the panel (excluding its backlight) can be reduced by 80-90%, Sharp said.

Higher performance of touch panel

Lastly, as for the higher touch panel performance, touches are detected when TFTs are not being driven. Because the influence of the noise generated by driving TFTs is eliminated, the detection sensitivity of the capacitive touch panel can be improved.