In the realm of capturing micro-events unfolding at lightning speed, scientists have introduced SCARF—Swept-Coded Aperture Real-time Femtophotography. This groundbreaking camera, developed by the team at Énergie Matériaux Télécommunications at the Research Centre Institut national de la recherche scientifique (INRS) in Quebec, Canada, is designed to observe phenomena too rapid for conventional sensors to detect. From semiconductor absorption to metal alloy demagnetization, SCARF has ventured into the realm of ultrafast imaging with unprecedented accuracy.

Unlike its predecessors, SCARF operates on passive femtosecond imaging principles, enabling the T-CUP system (Trillion-frame-per-second Compressed Ultrafast Photography) to capture trillions of frames per second. Spearheaded by Professor Jinyang Liang, a trailblazer in ultrafast imaging, this breakthrough builds upon his pioneering work in 2018, laying the foundation for the current project.

Miguel Marquez, co-first author of the study, elucidates, “Many compressed ultrafast photography systems face challenges in data quality degradation and the trade-off between sequence depth and field of view. These limitations stem from the operating principle, which necessitates simultaneous shearing of the scene and the coded aperture.”

Professor Liang further emphasizes SCARF’s potential in studying phenomena such as femtosecond laser ablation, shock-wave interactions with living cells, and optical chaos—a feat unattainable with previous ultrafast camera systems.

SCARF employs “chirped” ultrashort laser pulses, pulsating at an astounding rate of 156.3 trillion times per second, traversing through the subject under observation. Leveraging computational imaging modalities, the camera captures spatial information by allowing light to reach the sensor at slightly staggered intervals. A sophisticated computer algorithm decodes these time-staggered inputs, reconstructing a comprehensive image. Remarkably, individual pixels on a charge-coupled device (CCD) camera receive full-sequence encoding speeds of up to 156.3 THz, according to the research team.

In a remarkable feat, SCARF was assembled using off-the-shelf and passive optical components, marking a significant leap in ultrafast imaging technology. As SCARF continues to unveil the secrets of rapid micro-events, its potential applications span across various scientific disciplines, promising unparalleled insights into the dynamics of our world at the smallest scales.

By Impact Lab