New screen tech fuses oil with water

Oil and water don't mix, but they can make bright colours, says a start-up spun out of Philips.

Liquavista, a new company created by Philips Research and New Venture Partners, will seek to commercialise a technique for making screens for phones and MP3 players that relies on the fact that oil and water repel each other.

In electrowetting, each pixel cell contains a small amount of dyed oil and water and a layer of a material that can be converted from hydrophobic (water repelling) to hydrophilic by applying electricity. When the material is hydrophobic, the water pushes away from it and forces the dyed oil against the surface. The pixel, which has a light source behind it, then projects the colour of the dyed oil out.

In hydrophilic mode, the water draws toward the surface, shoving the dyed oil to the side, changing the colour projecting from the pixel. Flipping the pixels rapidly allows a screen containing millions of the pixel cells to create an image.

The dye in the oil can contain one or more colours. The technology is conceptually similar to the electronic paper being promoted by E Ink and Philips.

Liquavista claims that because the screens use dyes the colours are more natural. Electrowetting displays, at least according to lab results, also consume less power than traditional LCDs or organic light-emitting diodes (OLEDs).

Screens based on electrowetting are compatible with the manufacturing infrastructure for LCD screens and can be made in existing LCD factories, such as those owned by LG Philips. As a result, Liquavista says, this will help it bring the screens to market quickly and more inexpensively than one would expect with a new technology. Liquavista is already trying to strike deals.

One early application for electrowetting displays could be TV phones, a market in which Philips is investing considerably.

The Dutch electronics giant is currently in the middle of a rebuilding campaign. It has streamlined its organisation and greatly reduced the number of products it sells at any given time, a chronic problem in the past. The company has also begun to look more to its storied labs for product innovations. Philips, for instance, hopes by 2008 to release 3D TVs that can be used without glasses.

Electrowetting displays from Liquavista will be shown off at the Exhibition of the Society for Information Display 2006 starting on 6 June in San Francisco.