Daily news

12 February 2002

Sensor promises to sharpen digital images

A new kind of image sensor designed to provide a “true-colour” picture of a scene could improve digital image resolution for ordinary digital cameras, says the company behind the technology.

Digital cameras use millions of light-sensitive cells, or pixels, to detect light. In most digital cameras, each pixel can detect only one primary colour: red, blue or green.

But each light-sensitive cell in the X3 sensor, developed by US company Foveon, in fact contains three layers of pixels, allowing it to detect red, blue and green light. Foveon says this dramatically improves digital picture quality, because colours are detected in much more detail.

Some professional digital cameras can detect colour with similar accuracy by using a combination of the three photosensors in the same location, set at different angles. A beam splitter is used to separate incoming light and direct it to all three sensors. But these cameras are large, complex and expensive.


Foveon’s sensor makes use of the natural colour-separating properties of silicon. Different wavelengths of light penetrate silicon to different depths. So by placing sensors at the “correct” depth, each of the three light colours can be detected.

“Exciting technique”

“Previous methods for capturing complete colour were prohibitively expensive, and were only appropriate for very high-end systems,” said Jim Lau, CEO of Foveon. “We believe that Foveon X3 will be the preferred technology for future digital camera designs, at every price point.”

One expert in the area, who asked not to be named, says the technique is exciting because it combines the colour-separating quality of silicon with existing image sensor semiconductor technology.

Foveon says that the new sensor could be used in a range of electronic devices including hand-held computers, as well as cameras.