Zhou originally thought their technology would first be used in manufacturing settings, inspecting parts for tiny defects. Sept. 11, 2001, changed that. Now, with grants from the U.S. Department of Homeland Security, he said he expected their first products to be airport security screeners. They could enter the field of medical diagnostics within a few years.
X-ray technology has many limitations: it requires heating a filament to 1,000 degrees in order to produce the electrons that make an X-ray image; it requires large and bulky equipment; and its slow.
Early CT scanners use one x-ray source that rotates around an object. They have limited imaging acquisition speed. Siemens technology has addressed some of these issues, and the new nanotechnology enabled x-ray sources may improve future generations of CT scanners.
In 2005, UNC and Xintek announced a major advance by placing multiple carbon nanotube sources in an array. In this multi-pixel configuration all the energy sources the carbon nanotubes can fire at once from different angles, and they can fire repeatedly, in one-millionth of a second, Lu said. Fast enough to clearly capture a beating heart.
Carbon nanotubes are sheets of carbon rolled into a seamless tube about 300 times smaller than the diameter of human hair. They require much less energy to produce electrons which means they can be turned on and off very quickly at low energy. And, unlike conventional filaments, theyre microscopic.
In todays digital imaging technology, only the detector, the medium, is digital. Multi-pixel X-rays digitize the source. This, say Zhou and Lu, is truly digital.
College campuses are increasingly becoming the site of such discoveries and developments. Zhou, who worked at Bell Labs before coming to UNC in 1996, said industry is taking fewer risks in research and development than it did 20 years ago. Universities have to take up some of those risks with
|Contact: Clinton Colmenares|
University of North Carolina at Chapel Hill