New 'electronic paper' technology allows for 1 million color choices for your walls, electronics

Researchers at Philips have developed a new color e-paper technology that could allow you to change the color of an object as you see fit.

The technology, which offers more than 1 million colors to choose from, could be applied on walls inside the home or on the exterior of electronic devices -- allowing you to change the color of an object to match an outfit or mood with the touch of a button.

Color electronic paper, or e-paper, looks like conventional paper. But it can generate color using ambient light for rendition, like conventional paint. The benefits of Philips' new "e-skin" are many: the vibrancy of the color is maintained, even in bright outdoor conditions; the layer can be transparent; colors can be precisely tuned; and the technology is relatively inexpensive.

Better still, without requiring a backlight, Philips' e-skin is inherently energy-efficient. The technology has the potential to be used in the future for "electronic wallpaper," where you can adjust the color of walls for preference, or smart windows to regulate the daylight coming through your window.

“The first applications using the technology could be e-skins for small devices such as MP3 players or cell phones...the technology is highly scalable,” said Kars-Michiel Lenssen, principal scientist at Philips Research, in prepared remarks. "In the future it will be possible to use e-skins to bring new color and a new aura or 'vibe' to much larger equipment.

"Just as Philips' Ambient Experience uses light and color to make hospital diagnostic rooms far more welcoming, a large e-skin could make the concept fit for the MRI or CT scanner itself, potentially putting patients more at ease.”

Lenssen said the technology could be used where LEDs or OLEDs aren't preferred, such as in low-power devices or for a more subtle color application.

The science of the "e-skin" works using electrophoresis, which offers the ability to control the motion of particles in suspension with an electric field, because the particles carry a surface charge.

Monochrome e-paper, the kind found in e-book readers, works like so: By creating pixels with colored particles in a clear suspension, applying an electric field perpendicular to the surface makes the particles migrate to the top of the pixel, turning it dark.

But color, or polychrome, e-paper uses "in-plane electrophoresis." Instead of applying the field perpendicular to the surface, scientists apply it parallel to the surface. This causes the colored particles to spread across the pixel, again turning it dark. When the pixel is reset, the colored particles "hide" behind a mask, so the pixel is completely transparent. Philips built a "gate" electrode into each pixel, allowing for control over how many colored particles spread across the pixel -- in other words, the saturation and shade of each color.

Philips Research will present its work at the International Display Workshops 2009 in Japan this month.

This post was originally published on Smartplanet.com