A new camera design replaces the lens with an array of light receivers, resulting in a device that is ultrathin, light and flexible. Potential applications range from smart phone cameras to large flat telescopes in space.
The breakthrough comes from the laboratory of Caltech professor Ali Hajimiri. Hajimiri and his team replaced the camera lens with an optical phased array (OPA). Curved camera lenses focus incoming light onto film or an image sensor. The OPA uses a different method to manipulate incoming light to capture an image.
The integrated silicon photonics used in the new camera create an optical phased array receiver. Each element on the camera’s surface can be controlled electronically.
"Here, like most other things in life, timing is everything. 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," Hajimiri said.
By manipulating timing, a camera user can obtain the same kinds of views, from fish-eye to telephoto, that a conventional lensed camera provides.
The research team’s next step is to scale up the camera, which will entail designing chips that can support larger receivers with better sensitivity and precision.
"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 Hajimiri.
