The US Army has field-tested a lidar system that could provide the first line of defense in the event of an attack from biological agents. Researchers from Fibertek Inc. in Herndon, Va., and the Army's Chemical and Biological Defense Command at Aberdeen Proving Ground, Md., demonstrated a multiwavelength lidar system with detection capabilities between 310 and 445 nm. The system features two UV lasers and an IR laser that cause biological agents to fluoresce. The system, which also features a telescope/receiver assembly, can detect toxins up to 3 km away.