Sensor research ahead of the curve

Two developments in image sensor technology were announced this week which would fundamentally disrupt the photographic industry if they were to make it to commercial manufacture.  

Sony, Canon and Nikon have been working on curved sensors for some time, but Microsoft Research has now developed a sensor with three times more curvature than previously achieved.

‘When using curved sensors, it is possible to correct aberrations in a much more efficient way, making it easier to create very wide-angle lenses that produce sharp images across the entire field of view or to create fast lenses that produce better images in low light,’ said Neel Joshi, a member of the Microsoft Research team. ‘It is also more straightforward to make cameras that exhibit uniform illumination across the entire image.’

Microsoft Research has built a camera using the sensor which the researchers say produced higher resolution images across the entire field of view when compared to modern high-end DSLR cameras. 

‘We have created a prototype curved sensor camera with extraordinary performance. It surpasses, and in the case of illumination uniformity far exceeds, the performance of much larger professional camera systems like the Canon 1Ds DSLR equipped with a similarly fast f/1.2 50mm lens.’

Tests showed that curving the sensors did not change any of their electrical or imaging characteristics. When used in a prototype camera with a specially designed f/1.2 lens, the curved sensor had resolution more than double that of a high-end SLR camera with a similar lens. Toward the edges of the image, the curved sensor was about five times sharper than the SLR camera.

Lenslessness
Meanwhile, over at Caltech (California Institute of Technology), researchers have developed a sensor which doesn’t even need a lens to capture images. 

‘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,’ said Ali Hajimiri, the leader of the Caltech research team. ‘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.

‘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,’ he said. 

It’s early days yet, with the camera only capable of very low resolution images, but future applications could range from super thin cameras and smartphones through to huge ‘telescopes’ capable of imaging the universe.