E Ink, a US-based developer of electronic-paper-type flat-panel displays, has developed a colour version of its screen technology and is showing it at the FPD International exhibition, which opened on Wednesday in Yokohama.

The screen was developed by E Ink with colour-filter supplier Toppan Printing. The sample on show was completed within the past few weeks, according to Darren Bischoff, senior marketing manager at the Massachusetts firm. It’s based on similar technology to the company’s monochrome displays already in production and can be found in a handful of products such as Sony’s Librie electronic book reader.

The main difference is the addition of a colour filter. The prototype on display in Yokohama is a 6in display with 400x300 pixel resolution. That works out at 83 pixels per inch, which is half that of the commercial screen used in the Sony e-book reader.

The screens are reflective, which means they use ambient light reflected through the display rather than a backlight. They offer high contrast and appear much closer to paper in appearance than other flat-panel displays.

E Ink anticipates the display will be ready for commercialisation at the end of 2006, Bischoff said. Potential applications include ATM screens, digital camera viewfinders and mobile phones.