Machines that take x rays need a lot of power and as a result
are generally large, cumbersome contraptions. Anything that
needs to be x rayed has to brought to the machine. But there are
plenty of reasons develop a portable x-ray machine. A mobile
device could be carried into the sports field or battlefield to
diagnose injured people or it could be used by security
personnel to analyze packages at airports or check concealed
shipments at seaports for illegal contents. Scott Kovaleski, an
associate professor of electrical and computer engineering, and
some of his graduate students, found a way to make a lower-power
x-ray machine that’s only about the size of a stick of gum. That
means instead of bringing objects to an x-ray lab for analyze,
technicians can bring the x rays to the field. The key to the
small machine is a crystal of lithium niobate, which exhibits a
particular property known piezoelectricity. Piezoelectric
crystals generate a small electrical current when put under
mechanical stress, such as bei