E-paper with Photonic Ink

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The technology was developed with Geoffrey Ozin and Daniel Puzzo, among others, at the University of Toronto and Ian Manners at the University of Bristol, in the UK. The group demonstrated how 0.3-millimeter pixels--about the same size as many LCD displays--can independently generate a range of colors. Their results are published in the August issue of the journal Nature Photonics. "One single material can give all the necessary colors for a display without filters," says Arsenault.

In fact, by making the crystals slightly larger, it's also possible to take them beyond the visible-light range and into infrared, says Arsenault. The effects in this range would be invisible to the human eye but could be used to make smart windows that control the amount of heat that passes through them, he says.

This is a step forward, says Jacques Angele, a cofounder of Nemoptic. "The aim of these color-display technologies is to be comparable with paper. Unfortunately, the brightness of the [other technologies] today is limited to about 30 percent of paper."

"It's a spectacular innovation," says Edzer Huitema, chief technology officer of the Dutch firm Polymer Vision, based in Eindhoven. Even traditional screens, such as cathode-ray tubes, LCDs, and plasma displays, use three or even four differently colored pixels to generate color. "It's a major limitation for all color-display technologies," Huitema says. When the color of each pixel is controlled, not only does the color quality increase, but the resolution should also improve by a factor of three.

There is one display technology, however, that can tune individual pixel color, says Angele. Both Kent Displays, in Ohio, and Japanese electronics firm Fujitsu have been taking this approach, which, in essence, involves placing the three colored pixels on top of each other. But besides being technically difficult and expensive, this approach reduces the brightness of the colors, Angele says. "It's difficult to have an optical stack without optical losses."

Arsenault predicts that Opalux will have the first products on the market within two years, probably in the form of advertising displays. But, he says, it will be a long while before P-Ink will be in a position to completely replace traditional displays. "The caveat is that we are not at video speeds," Arsenault says.

Currently, the P-Ink system can switch pixels in less than a second, which is on par with other e-paper displays. "We're still early in our development, and there's a lot of room for [improving] the material and optimizing its performance," says Arsenault.