Now, researchers at the UCLA Henry Samueli School of Engineering and Applied Science have developed a novel, continuously running camera that captures images roughly a thousand times faster than any existing conventional camera.
In a paper in the April 30 issue of Nature (currently available online), UCLA Engineering researchers Keisuke Goda, Kevin Tsia and team leader Bahram Jalali describe an entirely new approach to imaging that does not require a traditional CCD (charge-coupled device) or CMOS (complementary metal-oxide semiconductor) video camera. Building on more than a decade of research on photonic time stretch, a technique for capturing elusive events, the team has demonstrated a camera that captures images at some 6 million frames per second.
"The most demanding application for high-speed imaging involves fast events that are very rare, rogue events or the proverbial needle in the haystack — in other words, unusual events that carry important information," said Jalali, a professor of electrical engineering and principal investigator of the project.
One of the applications he envisions for the camera is flow cytometry, a technique used for blood analysis. Traditional blood analyzers can count cells and extract information about their size, but they cannot take pictures of every cell because no camera is fast and sensitive enough for the job. At the same time, images of cells are needed to distinguish diseased cells from healthy ones. Today, pictures are taken manually under a microscope from a very small sample of blood.
But what if you needed to detect the presence of very rare cells that, although few in number, signify the early stages of a disease? Circulating tumor cells are a perfect example. Typically, there are only a handful of them among a billion healthy cells; yet these cells are precursors to metastasis, the spread of cancer that causes about 90 percent of cancer mortalities.
"The chance that one of these cells will happen to be on the small sample of blood viewed under a microscope is negligible," Jalali said. "To find these rogue cells — needles in the haystack — you need to analyze billions of cells, the entire haystack. Ultra-high-speed imaging of cells in flow is a potential solution for detection of rare abnormal cells."
The new imager operates by capturing each picture with an ultrashort laser pulse — a flash of light only a billionth of a second long. It then converts each pulse to a serial data stream that resembles the data in a fiber optic network rather than the signal coming out of a camera. Using a technique known as amplified dispersive Fourier transform, these laser pulses, each containing an entire picture, are amplified and simultaneously stretched in time to the point that they are slow enough to be captured with an electronic digitizer.
The fundamental problem in performing high-speed imaging, Jalali says, is that the camera becomes less and less sensitive at higher and higher speeds. It is simple to see why: At high frame rates, there is less time to collect photons in each frame before the signal becomes weaker and more prone to noise. The new imager overcomes this because it is the first to feature optical image amplification.
"Our serial time-encoded amplified microscopy (STEAM) technology enables continuous real-time imaging at a frame rate of more than 6 MHz, a shutter speed of less than 450 ps and an optical image gain of more than 300 — the world's fastest continuously running camera, useful for studying rapid phenomena in physics, chemistry and biology," said research co-author Goda, a postdoctoral researcher in the group.
One such phenomenon the group has studied with the new camera is laser ablation, an important technology that is the basis of laser medicine. The camera can capture laser ablation happening in real time, providing important clues for understanding the process and optimizing its effectiveness.
"Unlike other high-speed imaging methods, our approach does not require cooling of the camera or high-intensity illumination — problems that plague conventional CCD and CMOS cameras," said Kevin Tsia, a graduate student in the group and a co-author of the research.
The study was funded by the Defense Advanced Research Project Agency (DARPA), the U.S. Department of Defense's central research and development organization.
The UCLA Henry Samueli School of Engineering and Applied Science, established in 1945, offers 28 academic and professional degree programs, including an interdepartmental graduate degree program in biomedical engineering. Ranked among the top 10 engineering schools at public universities nationwide, the school is home to six multimillion-dollar interdisciplinary research centers in space exploration, wireless sensor systems, nanotechnology, nanomanufacturing and nanoelectronics, all funded by federal and private agencies.
Wileen Wong Kromhout | EurekAlert!
Further reports about: > Applied and Environmental Microbiology > CMOS > UCLA > Ultrafast, light-sensitive video cameras > World's fastest camera > charge-coupled device > communication between living cells > complementary metal-oxide semiconductor > elements of blood analysis > high-speed events > laser surgery > neural activity > photonic time stretch > shockwaves
A big nano boost for solar cells
18.01.2017 | Kyoto University and Osaka Gas effort doubles current efficiencies
Multiregional brain on a chip
16.01.2017 | Harvard John A. Paulson School of Engineering and Applied Sciences
An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...
Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...
Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.
While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...
Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales
Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...
Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.
As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...
19.01.2017 | Event News
10.01.2017 | Event News
09.01.2017 | Event News
20.01.2017 | Awards Funding
20.01.2017 | Materials Sciences
20.01.2017 | Life Sciences