A new optical approach from MIT that takes “time” into the equation when capturing images will enable the development of time-sensitive high-speed imaging systems.
It’s said that the eye can see and the brain can interpret as high as 1,000 frames per second (FPS), which means catching visual signals that happen in 1 millisecond or less, though there are conflicting views on the matter.
Most cameras typically take images at 24 FPS, which is enough to reproduce what the human eye and brain are designed and accustomed to.
Can you distinguish between 24 and 48 framerates, compared side by side in this video?
For research purposes, such as those involving fleeting chemical reactions, physical phenomena, or biological processes, scientists need ultrafast imaging systems.
High-speed streak cameras, a recent technology, can record up to billions of frames per second and are used for a variety of applications.
“Folding Time” for Ultra-High-Speed Imaging
Years ago, researchers at MIT Media Lab developed a streak camera system that captures visual signals at a trillion frames per second, so fast that it can shoot video of photons crossing the length of a bottle.
As fast as streak cameras go, including MIT’s, they rely on traditional optics and are beholden to its limits.
Now, another MIT Media Lab research team instead of designing a new streak camera system, they developed “novel photography optics” to greatly enhance the capabilities of such systems.
The team calls their technique “time-folded optics”, which basically considers “time” as a dimension and allows cameras to “capture images based on the timing of reflecting light inside the optics, instead of the traditional approach that relies on the arrangement of optical components.”
“When you have a fast sensor camera, to resolve light passing through optics, you can trade time for space. That’s the core concept of time folding. You look at the optic at the right time, and that time is equal to looking at it in the right distance. You can then arrange optics in new ways that have capabilities that were not possible before,” explains Barmak Heshmat, lead author of the paper.
Researchers say that time-folded optics pave the way to the miniaturization of optics in general and the development of ultrafast imaging systems with high time and depth sensitivity that would find many industrial applications, such as multi-spectral signature sensing systems and medical imaging.