SEL Semiconductor Energy Laborator and AFD Advanced Film Device showcased in co-operation with Sharp a 13.3 inch AMOLED DIsplay with a 8K resolution (7,680×4320 pixel). That means that this OLED Panel reach 664 pixel per inch, the companies reached that unbelievable resolution by combining white-light OLEDs with three kinds of microcavities to narrow wavelengths down to those of red, green and blue lights and applying color filters to them. Today most OLED panels reach the standard color gamut on NTSC on about 100 percent. This panel has a low red color reproduciblity and reach 84 percent. The companies using the CAAC-OS c-axis aligned crystalline oxide semiconductor technology for the backplane. Each OLED Each OLED is driven by 5 transistors and one capacitor (5T+C) including the circuit for compensating the fluctuation in threshold voltage. 497.664.000 pixel transistors are needed to realize that resolution. SEL, AFD and Nokia showcase also a three-fold OLED Displays at SID-2014 . Source

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Sharp and SEL showcase a 13.3-inch 8k OLED Panel – 664 PPI AMOLED prototype at SID-2014