DURHAM -- Have you ever been in the nosebleed section at a basketball game and tried to take a picture of the action? Zoom in on your cellphone and you’ll find that the players are indistinguishable squares, or pixels, that make up any digital image. If you brought your fancy new digital camera instead, the picture will be better, but the players will still be plagued by pixels.
Soon this may no longer be a problem. A team led by David Brady, professor of electrical engineering at Duke University, has created a camera, called AWARE-2, that is 50 times better than your digital camera. And according to a paper on their work published recently in Nature, they also have demonstrated they can make a camera thousands of times better.
The recipe? Make a bunch of cameras cooperate.
“We wanted to make an analogy with computers,” says Brady. “People kept trying to make computer processors faster and faster. Only recently did we realize parallel, multiple processors did the trick. You don’t need better ones, just more, working together.”
Your cellphone camera is probably about 1 megapixel, meaning each image it captures has 1 million pixels. If the image is square, it’s a grid with 1,000 spaces on a side, each filled with color to result in a picture.
A DSLR camera, the best kind of consumer camera, gets about 20 times more pixels in the same image, giving finer detail.
The strange thing is, your cellphone camera is outperforming your DSLR, in a sense. A cellphone camera can only, theoretically, capture about a megapixel because of the size of its lens opening, or aperture. Meanwhile, your DSLR has an aperture 10,000 times the size of your cellphone camera, meaning it should be able to capture 10 billion pixels. But current DSLRs capture less than 1 percent of that number.
More, not mega
The lens has been the roadblock to improving performance. A bigger aperture requires a more complex lens, and there’s a practical limit to complexity.
But by putting cameras in an array, the team, which included engineers from the University of Arizona and Distant Focus Corporation, was able to bump up the resolution, sidestepping the lens issue.
The operation of AWARE-2 is simple and elegant. In one-tenth of a second, 98 cameras blink in unison. Computer software then stitches the images together.
“It can take a (finely detailed) picture of you and your 500 best friends,” says Daniel Marks, an assistant research professor of electrical engineering at Duke, who contributed to the project.
The current prototype captures about 1 billion pixels – a gigapixel. But the team knows they can make a 50 billion pixel version with some minor tweaks, creating a camera many times better than the human eye. Once an image is captured, details can be revealed that the photographer could not see. People who appeared to the naked eye to be distant blobs in the background are easily identifiable in the picture.
The future of photos?
Despite being a prototype, AWARE-2 is surprisingly sturdy.
“It’s made of 80/20 aluminum, often jokingly called the engineer’s Erector set,” says graduate student David Kittle.
But it survived a 6,000-mile round-trip to Seattle and a bumpy SUV ride to a North Carolina lake. It’s unwieldy: 2-1/2 feet on a side, though it weighs only about 100 pounds. The group has attached wheels to the camera and rolled it around Duke’s campus.
The electronics to control the 98 little cameras are actually what make AWARE-2 so large, making Brady confident that the technology will trickle down to consumer cameras. After all, shrinking electronics has been done before.
In the short term, Brady envisions this technology as a platform for immersive experiences. Imagine “attending” a football game or concert online. The camera takes video of the entire stadium, but you can zoom in on any area.
Eventually, Brady and his team think the camera could be used for more efficient surveillance and could become a tool in medicine. Looking at cells to diagnose diseases now requires intricate positioning of a sample a small fraction of an inch from a microscope lens. Some day, your doctor may be able to just take a picture with a regular camera, go to lunch and zoom in later.