Sample photo taken with the Quanta Image Sensor. It is a binary single-photon image, so if the pixel was hit by one or more photons, it is white; if not, it is black.

QEPrize winner Eric Fossum, together with engineers from Dartmouth’s Thayer School of Engineering, has produced a new imaging technology that may revolutionise medical and life sciences research, security, photography and cinematography.

The new technology is called the Quanta Image Sensor, or QIS. It will enable highly sensitive, more easily manipulated and higher quality digital imaging than is currently available. The sensor can reliably capture and count single photons, generating a resolution as high as one megapixel, as fast as thousands of frames per second. Plus, the QIS can accomplish this in low light, at room temperature, using mainstream image sensor technology. Previous technology required large pixels, low temperatures or both.

Industry impact

For cinematographers, the QIS will enable IMAX-quality video in an easily edited digital format, while still providing many of the same characteristics of film. For astrophysicists, the QIS will allow for the detection and capture of better signals from distant objects in space. And for life science researchers, the QIS will provide improved visualization of cells under a microscope, which is critical for determining the effectiveness of therapies.

Building this new imaging capability in a commercially accessible, inexpensive process is important, said Fossum, so he and his team made it compatible with the low cost and mass production of today’s CMOS image sensor technology. They also made it readily scalable for higher resolution, with as many as hundreds of megapixels per chip.

“That way it’s easier for industry to adopt it and mass produce it,” said Fossum, who was recognised at the end of last year for his role in developing digital imaging sensors. On 6 December 2017, The Prince of Wales awarded Fossum the the Queen Elizabeth Prize for Engineering at Buckingham Palace, together with George Smith, Michael Tompsett and Nobukazu Teranishi.

High quality imaging using ‘jots’

“The QIS is a revolutionary change in the way we collect images in a camera,” said Jiaju Ma, who co-invented the technology with Fossum, Saleh Masoodian and researcher Dakota Starkey.

The QIS platform technology is unique, because the sensor incorporates ‘Jots’ – very small pixels which are sensitive enough to detect a single photon of light. The sensor is able to carry out ultra-fast scanning of the jots to produce an image. This allows the QIS to capture data from every single photon, enabling extremely high quality, easily manipulated digital imaging, as well as computer vision and 3-D sensing.

While the current QIS resolution is one megapixel, the team’s goal is for the QIS to contain hundreds of millions to billions of these jots, all scanned at a very fast rate.

Earlier this year, Masoodian, Ma and Fossum co-founded the startup company Gigajot Technology to further develop and apply the technology to a number of promising applications.

More information: J. Ma, S. Masoodian, D. Starkey, and E. Fossum, “Photon-number-resolving megapixel image sensor at room temperature without avalanche gain,” Optica 4, 1474-1481 (2017).

Image credit: Jiaju Ma