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Terahertz Imaging:Another Way to See Through Walls
311Stylee writes: "Wow. I've never even heard of this before, but it looks genuine with a writeup on MSNBC and Space.com . Existing technology is used to measure sea temperatures through clouds via satellite, but newer cameras could be used in a huge array of applications because of their ability to see through walls, clothing, smoke and clouds. Google gets 546 hits on T-rays, inlcuding one from AT+T Bell Labs."
For those that don't know this company is what was formerly the Defence Evaluation and Research Agency - ie the UK military's top secret researchers.
Following the election of Labour to power in 1997 the new government decided that the end of the cold war meant that this operation should make its own way in the commericial world. It's still government owned, at present, but will be sold off to the private sector at some time.
In effect these are the guys that gave the world radar and much else besides, So they mean business!
The image of a slice of bacon shows different levels of T-ray transparency for lean and fatty areas. Since fat absorbs almost no T-rays, it looks white; meat absorbs roughly 25 times as many T-rays, so it looks dark.
Many compounds changed the T-rays in characteristic ways, due to absorption or reflection. Molecules and chemical compounds, particularly in the gas phase, showed strong absorption lines that can serve as "fingerprints" of the molecules. Metals and other materials with high electrical conductivity were completely opaque to terahertz radiation.
The T-ray imaging technique is notable in that it can distinguish between different chemical compositions inside a material even when the object looks uniform in visible light. Also, most plastics are transparent to T-rays, so it can "see" inside plastic packaging.
I believe they use pulses to illuminate the targets, just so that you don't cook them
"It is a greater offense to steal men's labor, than their clothes"