Sony Corporation prototyped a 56-inch OLED TV that can display 4k2k video and will exhibit it at International CES 2013. Sony developed the OLED panel of the TV in cooperation with AU Optronics Corp. (AUO).

As a driver element, Sony employed an oxide semiconductor TFT instead of low-temperature polysilicon TFT, which is commonly used for OLED panels. Oxide semiconductor TFTs tend to be in an insulating state, and they have characteristics of semiconductor like Sharp Corp.'s IGZO (In-Ga-Zn-O). Driver elements using those oxides are drawing much attention in the display industry as a trump card for increasing resolution and lowering power consumption.

This time, Sony did not disclose the details of the composition of the oxide semiconductor. As for reasons why the company employed an oxide semiconductor TFT, it said that low-temperature polysilicon TFTs make it difficult to increase panel size while oxide semiconductor TFTs enable to easily improve the response speed of panel enough for use in TVs. As for the structure of the OLED device, a method that Sony calls super top emission was employed.

The method has already been employed for commercial LCD monitors that have been commercialized. Because it uses a structure in which light is extracted from the top side of a panel, the method makes it easy to realize a high-brightness panel with a high aperture ratio.