- New single-shot 10-trillion fps compressed ultrafast photography (T-CUP) technique captures any event with 100 femtoseconds frame intervals.
- It can be used to study interactions between matter and light at an unprecedented temporal resolution.
The pump-probe methods allow us to capture transient events through repeated measurements. However, several dynamics are either non-repeatable or hard to recreate. For instance, shock waves in laser-induced damages, light scattering in tissues, and irreversible crystalline chemical reactions.
Even if you recreate these phenomena, they would have significant shot variations and low occurrence rates. The pump-probe methods wouldn’t be able to provide decent accuracy and productivity.
To overcome these limitations, numerous single-shot (capturing the entire process in real time without recreating the event) ultrafast optical imaging methods have been built in recent years. They can capture 2D transient scenes in the optical range at more than 100 million frames per second.
However, to effectively capture such events, some sharp changes in the intensity and width of an ultrashort laser pulse require femtosecond-scale exposure. So far, the existing ultrafast imaging methods either require to repeat the event or struggle to achieve the necessary exposure time.
The World-Record For Real-Time Imaging Speed
To improve on the concept, scientists at Research institution in Quebec City, Canada, have built a single-shot 10-trillion fps compressed ultrafast photography (T-CUP) that captures any event with 100 femtoseconds frame intervals. It decreases the number of projection required to recreate a high-quality 3D spatiotemporal datacube.
The quality of the image wouldn’t be superior if you only use a femtosecond streak camera. That’s why they added another camera for capturing a static picture. Then they merged images taken by both cameras and applied Radon transformation (an integral transform used to reconstruct better images) to achieve high-quality pictures while capturing 10 trillion frames per second.
Numerous transient event might not be reflected by light intensity. Thus, the ability to measure other optical contrast like phase and polarization will improve the application scope of this methodology.
Schematic of the T-CUP system | Courtesy of researchers
In this study, 4 fundamental optical phenomena (listed below) were imaged in real-time, and T-CUP successfully recorded spatial focusing of a single picosecond pulse.
- A beam sweeping across the surface
- Spatial focusing
Reference: Nature | doi:10.1038/s41377-018-0044-7 | INRS
The first time this camera was used, it broke the world record by recording an event with one femtosecond laser pulse in real-time. It captured 25 frames at every 400 femtoseconds and detailed the light pulse’s intensity, shape, and angle of inclination.
T-CUP system | Courtesy of researchers
T-CUP literally freezes the light to observe phenomena in extreme slow motions. Authors believe that it can power a new generation of microscopes for material science and biomedical applications. Since it represents a fundamental shifts, it can be used to study interactions between matter and light at an unprecedented temporal resolution.
According to the researchers, there possibilities to increase T-CUP speed to up to 1 quadrillion frames per second. Such blazing fast speeds could help us image light-speed event and reveal how exactly photons interact with different substances.