This is a display that uses
iridescence to create a color image, as opposed to using glowing
phosphors like a
CRT or
liquid crystals,
LEDs, or
OLEDs like other display technologies. Each
pixel in the display is a miniature
Bragg Grating, reflecting
ambient light in the
wavelength of the color desired. There are currently two methods of
artificial iridescence being researched that are able to create a color image.
One method is being developed by a company called Iridigm and uses microelectromechanical systems (MEMS) technology to create what they call an Interferometric Modulator, or iMoD. Measuring from 25 to 60 microns on a side (400-1,000 dots per inch), the device creates a microscopic pit. Each iMoD cell has two states and can be switched between black and a single set color. A monitor using this technology would use multiple red, green, and blue cells in each pixel to create a full-color image.
Another method is being pursued by researchers at the University of Toronto, where they are working on a material called photonic ink (or "P-ink"), made up of spheres of silicon dioxide about 300 millionths of a millimeter across suspended in a gel made of metallic-doped polymer molecules. The structure of the resulting colloidal crystal can be controlled by thermoelectric means to create a Bragg Grating of any desired size, so each dot of ink on a piece of electronic paper would be able to reproduce any color.
An iridescent display would be thinner than other types of display, as it needs no backlight, and in the case of the P-ink, would literally be paper-thin. It also has the potential for perfect color reproduction, and would be easily visible in any light you could read by.