E Ink Holdings (Billerica, MA), better known simply as E Ink (8069.TWO), the supplier of black-and-white electrophoretic reflective displays (EPDs) for the Amazon Kindle and other handheld devices, has unveiled its latest full-color EPD, which relies on the company's advanced color ePaper (ACeP) technology.
No color-filter array required
E Ink says that for the first time, an EPD can produce full color at every pixel without the use of a color-filter array (CFA). The initial target application for ACeP will be for digital signage, rather than handheld devices, so that full-color Kindle is still a ways off in the future. ACeP achieves a full color gamut, including all eight primary colors, using only colored pigments. The display uses a single layer of electrophoretic fluid that is controlled using voltages compatible with commercial TFT backplanes. The intensity and variety of colors are achieved by having all the colored pigments in every pixel rather than by using the side-by-side pixel colors achieved with the conventional CFA. This eliminates light attenuation, which can be significant. Like regular E Ink ePaper, ACeP uses very little power and has paperlike readability under all lighting conditions, according to the company.
Other experimental approaches to creating a full-color EPD have used stacked backplane structures that are complex, difficult to manufacture, and costly; in contrast, the E Ink approach has a single backplane. Many materials and waveform inventions were required to independently control the position of the multiple color pigments, according to E Ink. Multiple 20" displays with a resolution of 1600 X 2500 pixels at 150 ppi have been constructed. ACeP displays are being demoed now during SID’s Display Week (May 22 to 27, 2016; San Francisco, CA) at E Ink’s booth (#521) at the Moscone Conference Center from Tuesday, May 24 through Thursday, May 26.