Lensless Multiview Camera Cleverer Than Lytro And PureView Combined
A lensless, focussing-free camera that can take photos from multiple angles simultaneously, building up either different perspectives of a scene or combining data to produce faster, higher-detail images, could revolutionize the digital camera industry, its developers have teased. The prototype, developed by a team led by Hong Jiang at Bell Labs, eschews traditional glass or plastic lenses and replaces them with an LCD panel that works as a dynamic aperture. Using the system, multiple imaging sensors can in fact share the same aperture.
In fact, the LCD panel operates as an array of apertures. Each pixel can be independently adjusted to allow through light and, by randomly opening up a number of them in a sequence, the imaging sensor can capture multiple perspectives of the same scene, which are then combined.
"Although seemingly random, each of these snapshots is correlated because they record the same scene in a different way" the Bell Labs group explains. "And this is the key that the team use to reassemble an image. The process of compressive sensing analyses the data, looking for this correlation which it then uses to recreate the image."
As a result, the camera can snap a frame from as little as a single sensor and a single pixel opening each time, with great speed advantages over traditional cameras. There's also no lens aberration, and everything in the frame is in focus.
Throwing in a second sensor, meanwhile, captures a new perspective on the same scene, simultaneously to the first. That can either be used to increase the quality of the end image, similar to how Nokia's 808 PureView combines readings from proximate pixels to get more accurate data overall, or to build up multiple views of the same scene.
Cameras that can do more than snap the average scene are becoming a hot research topic, particularly in mobile. Lytro has been offering images that are refocusable after the shot has already been taken for some time now, while Nokia is expected to include similar technology in future handsets thanks to its investment in the multi-sensor arrays developed by Pelican.
The current Bell Labs prototype is obviously too large to fit into a phone or a tablet, but assuming the technology can be slimmed down, it might open the door to another way of taking shots on the move. For instance, the speed advantages could mean that images could be captured more swiftly and thus avoid motion-blur, while the lack of moving parts might make for sturdier, smaller smartphones.