E Ink color
E Ink color technologies include E Ink Triton, E Ink Spectra, and E Ink Prism. Opening statements below are from their web site. Technically E Ink has always had color capabilities since you could pick any two colors of ink. The number of colors is the limitation.
 E Ink Spectra
E Ink Spectra™ is the first three pigment electronic ink offered in mass production and is available for retail and electronic shelf tag labels. EPDs using Spectra offer the same high-contrast, sunlight readable, low-power performance attributes of our other display types - now with a pop of color. The first generation of Spectra features black, white and red or yellow pigments, and we expect to release additional colors in the future.
 E Ink Prism
E Ink Prism™ will transform the way spaces and surroundings are experienced. Manufacturers and designers will now have the ability to integrate innovative films with architectural products to dynamically change colors, patterns, and habitats. E Ink Prism utilizes E Ink’s bistable ink technology in a film that can transform architectural materials into dynamic, one of a kind experiences and designs. It is visually similar to paint because it uses the same pigments found in the printing industry. But unlike traditional paint E Ink Prism can change the color of a wall, ceiling panel, or entire room instantly, at the flip of a switch.
E Ink’s new color display, Advanced Color epaper called ACeP for short, uses virtually the same technology as the black and white displays you find in eReaders except that the pigments themselves are colored and transparent. This is the first time E Ink has been able to offer full color with every pixel, leading to rich color saturation. Despite the new color capabilities, ACeP is said to retain paper-like readability in various light conditions, the biggest draw for e-ink displays.
The richness of the colors is achieved by having all the colored pigments in every picture element (pixel) rather than the side-by-side pixel colors achieved with a Color Filter Array. Current application is “digital signage.” They have a sample 20-inch ACeP displays with a 1600 x 2500 resolution. Observations of the sample indicate that color changing is relatively slow with a significant flash and color saturation is limited.
 Current Specifications
- Screen sizes up to 20".
- 150 PPI
- 8 primary colors with full gamut display.