Lensless ‘camera of the future’ opens new imager applications
The OPA consists of a large array of electronically controlled light receivers, each of which can add a time delay – or phase shift – to the light it receives, enabling the camera to selectively look in different directions and focus on different things. As described by the researchers, the OPA “does computationally what lenses do using large pieces of glass” – that is, manipulate incoming light to capture an image.
“With our new system, you can selectively look in a desired direction and at a very small part of the picture in front of you at any given time, by controlling the timing with femto-second—quadrillionth of a second precision,” says Ali Hajimiri, Bren Professor of Electrical Engineering and Medical Engineering in the Division of Engineering and Applied Science at Caltech and the principal investigator of an Optical Society of America (OSA) paper describing the new camera.
“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,” he says.
According to the researchers, this system represents proof of concept “for a fundamental rethinking of camera technology.” The potential applications are endless, they say.
“Even in today’s smartphones, the camera is the component that limits how thin your phone can get. Once scaled up, this technology can make lenses and thick cameras obsolete,” says graduate student Behrooz Abiri, and coauthor of the OSA paper. “It may even have implications for astronomy by enabling ultra-light, ultra-thin enormous flat telescopes on the ground or in space.”
“The ability to control all the optical properties of a camera electronically using a paper-thin layer of low-cost silicon photonics without any mechanical movement, lenses, or mirrors, opens a new world of imagers that could look like wallpaper, blinds, or even wearable fabric,” says Abiri.
The researchers plan next to scale up the design to enable much larger receivers with higher resolution and sensitivity. For more, see “An 8×8 Heterodyne Lens-less OPA Camera.”
Related articles:
Lens-free flat camera addresses emerging imaging applications
Lensless camera adjusts focus after image capture
Rambus demos lensless eye tracking sensor
Microsoft curved image sensor promises ‘ideal’ camera