A new security screening technology once criticized as working too well -- it exposed everything hidden beneath your clothes, weapons and otherwise -- has now cleaned up its act. Developed by the Pacific Northwest National Laboratory, the three-dimensional full-body scanner uses harmless long-wave radio signals, about the same frequency as satellite television signals, to recognize concealed weapons. Unlike a metal detector, the so-called holographic scanner detects metallic and non-metallic objects, like carbon-fiber blades, liquids, ceramics and plastic explosives. Privacy concerns stalled the technology, but now researchers say they have developed a PG-rated version. New hack-proof computer software displays the hidden objects on a gender-neutral mannequin. "Operators never see an actual body," says PNNL engineer Doug McMakin. The aptly named start-up company, SafeView, based in Menlo Park, California, is targeting to sell the first production units in early 2004 for $50,000 -- twice the price of a typical metal detector, though immeasurably more secure. SafeView says likely customers include the Department of Justice, airports and prisons.