Today's blimps are fat, happy billboards hovering above sporting events. Tomorrow's blimps may well play a much more serious role: airborne surveillance.
U.S. Navy engineers have equipped an airship with a system known as LASH, or Littoral Airborne Sensor Hyperspectral. Basically, LASH works by detecting colors. Every object reflects light in its own unique pattern, invisible to the naked eye. LASH, developed by Science and Technology International in Honolulu, is essentially a camera that feeds the light pattern--usually in the infrared or ultraviolet range--into an onboard computer. The computer differentiates wavelengths and produces an image showing a real-time picture with enhanced color variations. "For instance, man-made camouflage is a couple of frequencies off from the surrounding natural color spectrum," says Steve Huett, director of airship advanced system development for the Office of Naval Research. "Your eyeball could never tell the difference."