Researchers at the Harvard School of Engineering and Applied Sciences (SEAS) have developed a way for photographers and microscopists to create a 3D image through a single lens, without moving the camera.

Offering a workaround, Crozier and graduate student Antony Orth essentially compute how the image would look if it were taken from a different angle. To do this, they rely on the clues encoded within the rays of light entering the camera.

The key, they found, is to infer the angle of the light at each pixel, rather than directly measuring it (which standard image sensors and film would not be able to do). The team's solution is to take two images from the same camera position but focused at different depths. The slight differences between these two images provide enough information for a computer to mathematically create a brand-new image as if the camera had been moved to one side.

By stitching these two images together into an animation, Crozier and Orth provide a way for amateur photographers and microscopists alike to create the impression of a stereo image without the need for expensive hardware. They are calling their computational method "light-field moment imaging"—not to be confused with "light field cameras" (like the Lytro), which achieve similar effects using high-end hardware rather than computational processing.

Importantly, the technique offers a new and very accessible way to create 3D images of translucent materials, such as biological tissues.

Biologists can use a variety of tools to create 3D optical images, including light-field microscopes, which are limited in terms of spatial resolution and are not yet commercially available; confocal microscopes, which are expensive; and a computational method called "shape from focus," which uses a stack of images focused at different depths to identify at which layer each object is most in focus. That's less sophisticated than Crozier and Orth's new technique because it makes no allowance for overlapping materials, such as a nucleus that might be visible through a cell membrane, or a sheet of tissue that's folded over on itself. Stereo microscopes may be the most flexible and affordable option right now, but they are still not as common in laboratories as traditional, monocular microscopes.

The new technology also suggests an alternative way to create 3D movies for the big screen:

"When you go to a 3D movie, you can't help but move your head to try to see around the 3D image, but of course it's not going to do anything because the stereo image depends on the glasses," explains Orth, a Ph.D. student in applied physics. "Using light-field moment imaging, though, we're creating the perspective-shifted images that you'd fundamentally need to make that work—and just from a regular camera. So maybe one day this will be a way to just use all of the existing cinematography hardware, and get rid of the glasses. With the right screen, you could play that back to the audience, and they could move their heads and feel like they're actually there."

This story is reprinted from material from the Harvard School of Engineering and Applied Sciences, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.