Trex Enterprises has developed a second-generation passive millimeter-wave imaging system for detection of concealed weapons and explosives at standoff ranges. Passive millimeter-wave sensors form an image from naturally emitted blackbody radiation in the millimeter-wave portion of the electromagnetic spectrum. Radiation at this wavelength passes through most types of clothing, allowing the user to acquire an image of any articles on a suspect"s person that differ significantly from the human body in their reflectivity or radiometric temperature at millimeter-wave wavelengths. Trex Enterprises previously demonstrated a first-generation concealed weapon detection system with the ability to detect handguns and knives under heavy clothing at a range of 27". The second-generation imager, while similar in concept, has an improved field-of-view and a much reduced size and weight. The imager is to be put through a battery of tests by both Trex Enterprises and the National Institute Of Justice to determine its ability to detect both metallic and non-metallic knives and handguns as well as various types of explosive devices. The tests will be conducted indoors and outdoors at various ranges.© (2004) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.