T‘he University of New Mexico is creating a new generation of chips for infrared cameras that could change today’s black-and-white thermal images to color.
That could greatly enhance the ability of infrared imaging to detect and distinguish things, improving their use in medical, industrial and military applications, said Steven Brueck, director of UNM’s Center for High Technology Materials, where the research is taking place.
“Making infrared cameras more capable will improve uses in things like medical diagnostics, or in industrial processes, such as detecting gas leaks and distinguishing the type of gas that’s escaping,” Brueck said. “It could even help pilots, because when planes land, they use infrared cameras, especially at night.”
The research has attracted Raytheon Vision Systems, a subsidiary of Raytheon Co. and one of the world’s leading suppliers of infrared technology. The company provided $80,000 to help finance CHTM work for the next year, with the option of more funding and collaboration after that, said Ed Smith, program manager for emerging technologies at Raytheon Vision Systems.
“We’re always looking for new advancements that can compliment our product development,” Smith said. “You can count on one hand the number of university research groups doing this type of work worldwide. CHTM is in a lead bracket for this research globally.”
About 40 people at UNM are working on the research, led by Brueck and Sanjay Krishna, an electrical and computer engineering professor who was previously associate director of CHTM. Sanjay created an infrared detector program about 10 years ago at CHTM, which until then had focused primarily on laser-related work and manipulation of materials at the nanoscale.
Krishna has specialized in creating “quantum dots” – incredibly small, three dimensional structures that can manipulate light in unique ways for use in infrared cameras and detectors. His team also creates super lattices, or two-dimensional nanostructures made by laying materials in crisscrossed layers on top of each other.
Those structures are about 10,000 times smaller than a human hair. They can manipulate light to capture details with greater efficiency than the structures commonly used in today’s infrared imaging technology. As photons, or light particles, hit the quantum dots or super lattices, they get converted to electrons, turning optical signals into electrical signals that can then be measured and manipulated for infrared sensors and cameras, Krishna said.
The CHTM is one of only two universities in the U.S. that can make such nanoscale structures for infrared technology, thanks to a $1.5 million molecular beam epitaxy machine that CHTM acquired in 2010. That machine allows researchers to build semiconductor nanocrystals up one atom at a time in layers, kind of like lego toys, Krishna said.
Raytheon and other companies already had supported the quantum dot and super lattice work being done at CHTM, because that emerging technology adds more capabilities to infrared imaging. In fact, Krishna and his wife, UNM cancer biologist Sanchita Krishna, launched a startup company in 2010 called SK Infrared LLC to create an infrared camera that measures heat on lesions to detect skin cancer rather than perform a biopsy.
But that technology is still based on black-and-white infrared imaging. To add color, Brueck and Krishna are now incorporating artificial materials, known as “metamaterials,” into quantum dots and super lattices that better absorb photons and can more easily be manipulated at the nanoscale, Krishna said.
“Metamaterials are substances with properties that you can tweak so that it responds to light very differently than natural materials,” Krishna said.
The materials help show colors in photons that are otherwise undetectable, potentially providing much more information in infrared imaging.
“By turning on color in the images, you can better distinguish details to identify things,” Krishna said.
A lot more research and development is needed before the technology is incorporated into commercial or military infrared cameras and sensors, but scientists say CHTM’s work has major potential. Apart from Raytheon, Los Alamos National Laboratory and Sandia National Laboratories are also collaborating with UNM.
— This article appeared on page B1 of the Albuquerque Journal