By Peter Weiss
Frontline troops depend on extraordinarily sensitive optical detectors in systems that test the air for anthrax or other harmful agents. Other prototype systems use such detectors in devices that transmit secure communications. Yet the detectors, known as photomultiplier tubes, tend to be large, fragile, and power-hungry.
Now, engineers have created a microscale ultraviolet light detector that’s sturdier and consumes far less power, compared with ultraviolet-sensitive tubes. Field instruments using this detector and others tuned to other wavelengths could shrink field instruments from the size of a soldier’s helmet to the dimensions of a cell phone.