Knife and guns appear visible through the t-ray technology becoz its sharp edges scatter the radiation. And yet, unlike X-rays, T-ray screeners could be used routinely on people, because the radiation is harmless.
But some terahertz imagers have another ability, one not even claimed by the comic-book specs: not only can they see hidden objects, but they can tell what those objects are made of. Many explosives, including all the plastic explosives popular with terrorist groups, reflect and transmit a characteristic combination of terahertz waves that make them distinguishable from other materials, even those that might seem identical to the eye and hand.
They have “standoff capability,” meaning they can see a few meters away, a very desirable feature in the security business.In just two or three years, versions that can see at a distance of tens of meters should be available, which would be a great safety boon to security personnel. There are lots of uses outside of the security arena for T-rays, too. Drug companies are buying T-ray imagers for their ability to distinguish good pills from bad by their spectral signatures. T-rays can distinguish normal skin tissue from tumors even when a trained dermatologist cannot. Manufacturers can do the mundane job of checking the contents of a box without opening it, or they can perform such crucial tasks as finding the invisible defects in the protective coatings on an aircraft’s wings. NASA recently commissioned a T-ray imaging company, Picometrix, in Ann Arbor, Mich., to build a scanner to look for tiny holes and other structural failings inside the foam that lines the external fuel tanks in the space shuttle fleet. A chunk of that foam fell away in 2003 and led to the deaths of seven astronauts and the fiery destruction of the Columbia.
they’re not quite what we think of as radio and not quite what we expect from light. They can radiate from metal antennas as radio waves do, but they also bounce off ordinary mirrors as light does. They can be focused with silicon lenses but are typically sensed in a circuit by their electric field.(range =500 gigahertz and 10 terahertz That region is largely beyond the reach of pure radio frequency technology such as microwave circuits, requiring combinations of electronics and optics instead.)
for more details visit t-rays
Comments