Researchers at Caltech have come up with a new digital camera design that does away with the need for optics. The new technology uses an optical phased array to capture light at different times with different focus, thus creating an entire image.
Traditional cameras require a lens or pinholes to focus light onto a sensor, which makes them bulky. This would eliminate that protruding camera lens from the back of cellphones. Professor of Electrical Engineering at Caltech Ali Hajimiri says that it could be made thinner than paper.
Hajimiri explains the optical phased array system by comparing it to a phased array pair that humans already have:
People, if you will imagine, have a very simple phased array already. That is, your ears, of course. If you are at a party and talking to someone and the conversation is very boring you might start listening around the room for other sounds or conversations. This is very much like the phased array we’ve built.
As a proof of concept they arranged 64 array sensors in an 8X8 grid. Each sensor is exposed to light, but through sub nano-second timing they capture specific directions to create an entire image.
Devices made using this technology would be incredibly cheap. No motors, gears, mirrors, or lenses are needed. The whole thing is a silicon chip.
The new method for capturing images has some very high-end photography applications. Theoretically you can have any size aperture you want. This gives handheld cameras that are paper thin the ability to shoot as though they had a telescopic lens. It also eliminates the need to carry several specialty lenses, according to Hajimiri:
We’ve created a single thin layer of integrated silicon photonics that emulates the lens and sensor of a digital camera, reducing the thickness and cost of digital cameras. It can mimic a regular lens, but can switch from a fish-eye to a telephoto lens instantaneously—with just a simple adjustment in the way the array receives light
Future cameras with this technology will manipulate waves of light to form images, instead of twisting lenses to find focus. Hajimiri told us that he expects this technology to be available commercially in five or six years.
How long before it replaces high-end cameras and revolutionizes photography? “I think maybe 10 years, but again that’s very hard to say. There’s still a lot of work to be done,” Said Hajimiri.
No matter how long it takes – the world is going to be happy to have a camera that doesn’t make their devices bulky.