1 Mpixel single-photon camera achieves 24kframe/s
Based on new-generation image sensor technology that uses single-photon avalanche diodes (SPADs), the camera is reported to have a 3.8ns time gating (consider this as the shutter speed), enabling it to capture extremely fast motion or alternatively to increase dynamic range. The new sensor was proven to detect photons across its one million pixels at 24,000 frames per second, speeds ideally suited for LiDAR applications or 3D-imaging for augmented reality systems.
“Thanks to its high resolution and ability to measure depth, this new camera could make virtual reality more realistic and let you interact with augmented reality information in a more seamless manner,” said Edoardo Charbon from the Advanced Quantum Architecture Laboratory (AQUALab) at EPFL. Charbon developed the idea for the new camera and is the founder and head of AQUALab, where the image sensor was designed.
In single-photon time-gated time-of-flight (ToF) experiments described in the Optica journal under the paper title “Megapixel time-gated SPAD image sensor for 2D and 3D imaging applications”, the researchers demonstrated an extended dynamic range and spatially overlapped multi-object detection. The sensor was used to capture 2D/3D scenes over 2m with resolution of 5.4mm and precision better than 7.8mm.
The authors describe how they created one of the smallest SPAD pixels ever, with a pitch of 9.4µm, in 7 T and 5.75 T configurations, each pixel drawing less than 1 microwatt while maintaining speed and timing precision.
“For transportation applications, this new camera could help achieve unprecedented levels of autonomy and safety by enabling multiple low-power LiDAR devices to be used on a vehicle, providing fast, high-resolution 3-D view of the surroundings,” said first author, Kazuhiro Morimoto from Canon Inc. in Japan. “In a somewhat more distant future, quantum communication, sensing and computing could all benefit from photon-counting cameras with multi-megapixel resolution.”
Next, the researchers aim to improve the performance and timing resolution of their camera and further miniaturize the components to make it more practical for a variety of applications.
EPFL – www.epfl.ch