Toppan Printing Co Ltd developed a prototype of a 32-inch flexible color electronic paper (e-paper) in cooperation with E Ink Holdings Inc.
According to Toppan Printing, it is the world's largest-screen flexible color e-paper that uses one driving TFT substrate (back plate). The company and E Ink will continue to co-develop technologies for the e-paper, aiming to commercialize it by the end of 2017.
The display panel of the prototype was manufactured by E Ink. It consists of the "E Ink Pearl" (a front plate for color display) and the "Mobius" (a back plate using a flexible base material for high-resolution display).
Though it is difficult to form color filters on the flexible back plate with a high positional accuracy due to the characteristics of the material, Toppan Printing solved this issue. Moreover, by developing a color filter optimized for the display properties of reflective e-paper, it became possible to reproduce brighter color tones.
The prototype has a screen size of 691.2 x 388.8mm (32 inches), a color filter of RGBW square pattern, a pixel count of 1,280 x 720 (the number of sub-pixels of the back plate: 2,560 x 1,440), a pixel pitch of 540μm and a contrast ratio of 10-20:1 (representative value). It can display 4,096 colors.
Toppan Printing exhibited the prototype at Auto-Id & Communication Expo 2016, which runs from Sept 14 to 16, 2016, at Tokyo Big Sight.