Sharp explained the technologies used to realize its 7,680 x 4,320-pixel (8k4k) "Super High Vision" 85-inch LCD display at SID 2012, which took place from June 3 to 8, 2012, in Boston, the US (thesis number: 58.1).
The display was announced by Sharp and Japan Broadcasting Corp (NHK) in May 2011 . Its brightness and drive frequency are 300cd/m2 and 60Hz, respectively. It can display 1 billion colors (10 bits for each of red, green and blue (RGB) colors).
First, Sharp explained the reason why it chose the 85-inch size. In consideration of the effect of an 8k4k display on viewers, the capacity of the company's production line, the capability of being delivered to Japanese households (the sizes of elevators and entrance doors), etc, it concluded that the 85-inch size is the maximum size for Japanese households.
The resolution of the 85-inch 8k4k panel is 103ppi. And the resolution of Sharp's 64-inch 4k2k panel is 72ppi. So, if the current technology is applied without any change, the aperture ratio of pixel decreases, potentially lowering brightness.
Therefore, Sharp employed the UV2A photo-alignment technology, low-resistance copper (Cu) lines and LED backlight with a high luminous efficiency to ensure a high aperture ratio and realize the brightness of 300cd/m2. The company did not announce the employment of Cu lines in May 2011.
Furthermore, to display video with a pixel count of about 30 million at 60Hz, Sharp made changes to its driving method. Specifically, the 8k4k panel is split into four 4k2k areas, and each area is independently driven. Source wiring is placed on the right and left sides of the sub-pixels and driven for every other sub-pixel from the top.