Mitsubishi Electric Corp demonstrated its 155-inch (1,920 x 3,456mm) display using organic EL light emitting devices at CEATEC JAPAN 2009.
The display received high commendation from visitors partly because its luminance is three to four times higher than those of normal LCD TVs and Shinoda Plasma Corp's Plasma Tube Array (PTA) display, which is similar to the new display in terms of thickness and screen size.
The pixel pitch is about 3mm. But when watched from a distance of more than 2m, the display looked fine enough for me. The pixel pitch of large-size LED displays is normally 4 to 6mm. There are some LED displays with a pixel pitch of 3mm, but they use many LEDs and are too expensive to become popular, Mitsubishi Electric said.
According to Mitsubishi Electric, with the method the company developed this time, it is possible to manufacture displays having a high resolution at a lower cost compared with LED displays.
The large-size display was realized by combining 720 units composed of four OLED panels. Each of the panels measures 96 x 96mm and has 256 pixels. And each pixel consists of RGB sub-pixels that are arranged in a stripe pattern.
The new display is a passive-matrix type and does not require TFTs. The organic EL materials are low-molecular materials, and they are formed into films by vacuum evaporation method.