T-ray tool takes extreme measures
IOWA STATE (US)—A terahertz ray (T-ray) facility is allowing researchers to take a close and unique look at materials reliability, biofuels combustion, environmental clean-up, cancer screening, biomass conversion, ionic liquids, and many other research areas in science and engineering.
“There are a lot of applications for this technology and we’re discovering more and more of them,” says Thomas Chiou, an associate scientist at Iowa State University’s Center for Nondestructive Evaluation. The T-ray instrument emits and reads high-speed pulses of silent and invisible terahertz rays.
Chiou says NASA was the first to demonstrate the technology’s potential in nondestructive evaluation when engineers successfully used T-rays to look for defects in the foam that insulates and protects the Space Shuttle’s external fuel tanks.
“This machine represents a new frequency regime in which measurements can be made,” says R. Bruce Thompson, an Anson Marston Distinguished Professor in Engineering and director of the Iowa State center. “When you have a new way to make measurements, there are new things you can do in applied and fundamental sciences.”
Chiou says the new T-ray instrument is made possible by advances in ultra-fast laser technology. It emits terahertz rays that are focused on a material or object. The rays reflect back to the receiver and the instrument’s controlling computer records and displays the resulting data. That data can show 3-D spatial images of the object’s inner structures and also provide spectroscopic analyses of chemical and physical compositions.
The rays—they’re between microwave and infrared rays in a relatively unexplored segment of the electromagnetic spectrum—can penetrate many common gases, non-metal solids, and some liquids, Chiou explains. They’re not known to cause harm to people or materials. They also show unique signatures for many materials.
Chiou says the Iowa State facility will feature two separate systems. One is a time-domain pulsed system suitable for high-speed, time-resolved imaging tasks. The second is a frequency-domain, continuous-wave system for applications requiring finer resolution.
Researchers at the facility are looking for university and industry collaborators who want to see what the new equipment can do for their projects.
“We see this technology as a way to encourage innovative ideas,” says Thompson. “We’re excited just to try some new things.”
Iowa State acquired the instrument with support from the National Science Foundation’s Major Research Instrumentation program.
Iowa State University news: www.news.iastate.edu/