Kodak increases digital camera sensitivity

Kodak has developed a relatively straightforward change to digital camera image sensors that could help with a common photography problem: poor performance in dim conditions.

The new technology, to be unveiled on Thursday and used in products in 2008, increases light sensitivity of existing image sensors by a factor of two to four, said Mike DeLuca, marketing manager for Kodak's image sensor solutions group.

Translated into photography terms, that means a camera's shutter speed could be cut in half or a quarter, helping cut camera shake or motion blur problems. Alternatively, it could let photographers shoot in low light with less image 'noise' -- the pesky multicolour speckles that degrade photographs.

"That's the real bane when you think about it. There's just not enough light to collect," said IDC analyst Christopher Chute. Of Kodak's new method, he said, "It's pretty revolutionary."

Light sensitivity has become a serious problem in digital cameras, particularly as higher megapixel counts have increased noise levels in image sensors.

And unlike some efforts to improve digital cameras, the new Kodak technique can be applied to any existing image sensor, leading Kodak to hope it will be able to license the high-sensitivity technology far and wide.

"We absolutely feel there is a big opportunity for this... to become a new standard in the industry," DeLuca said. "We really want to propagate this out as far as the market feels it should be taken."

Do you see what I see?
Kodak's new method better reflects how human eyes actually work, separately registering colour and brightness information -- and devoting more pixels to brightness, where the human eye is sensitive to detail.

The company's technology doesn't require any new fundamental changes to the heart of the image sensor, where a grid of electronic detectors converts incoming light first into electric signals and then digital information. Instead, the new technology adds some neutral 'panchromatic' pixels to the usual array of red, green and blue pixels in the grid, then uses a different software algorithm to reconstruct the full-colour images from the sensor output.

In nearly all of today's digital cameras, each sensor pixel detects either red, green or blue, with those particular colours placed in a quasi-checkered arrangement called a Bayer pattern after the Kodak engineer, Bryce Bayer, who developed it. Every second pixel registers green light, while the remaining pixels capture either red or blue.