You’ve probably never seen a camera lens like the one Shree Nayar is working on in his lab at Columbia University. It looks like a clear sheet with a bunch of bumps on it, and unlike, say, the lens inside your smartphone, it’s totally flexible, and bending the sheet increases its field of view.
This prototype of a flexible lens array could eventually make it possible to add cameras to all kinds of surfaces: it might wrap around a car to help with autonomous driving or simply provide better visuals while you’re backing up, or circle a light pole to take surveillance video in 360 degrees. Nayar also envisions it being combined with a flexible display and built into a thin, flexible camera—a concept for this and other applications are shown off in this video.
“You could have an entire bumper with this kind of a system, or any surface, for that matter, depending on what the application is,” Nayar says.
To get a sense of how this could work, researchers emulated a flexible sheet camera with their bendy prototype. First, they molded a very-low-resolution flexible lens array—just 33 by 33 lenses—in silicone rubber. Then they layered it atop a flexible sheet of plastic with holes in it and a diffusing sheet, and held all these layers in place in a sort of vise that could be used to bend them while a computer monitor projected images from above. While bending all the layers at various angles, researchers captured the images formed on the diffusing sheet (such as multicolored dots and a boy with a horse) with a digital camera that they set below the whole contraption.
Nayar thinks this flexible-sheet concept could eventually be used to manufacture a higher-resolution image sensor than what Daniel Sims, a graduate student and lead author of a paper on the subject, was able to make by hand. And he says the researchers are now trying to figure out if deforming the lenses can be helpful for doing things like zooming.
He notes, however, that in order to really make the technology useful we’ll need to see more progress with other types of flexible electronics and organic sensors that can be printed on various surfaces and aren’t based in silicon, unlike traditional image sensors. A fully flexible camera, for instance, would need a flexible display—something that’s already been shown off by companies like LG and Samsung, but isn’t yet available in consumer electronics beyond the occasional curved screen.
John Rogers, a professor at the University of Illinois at Urbana/Champaign whose research includes flexible and stretchable electronics and biologically inspired camera design, agrees. He thinks the researchers did a good job demonstrating the optics, but says the lens array would need a flexible, high-density, high-pixel-count photo sensor, which isn’t yet available, to actually work as a camera.
Still, he says, “I think it’s neat work.”