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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!
"For home security purposes - see through walls to see if there is an intruder in your bedroom, or if the baby sitter is carrying a gun under her blouse"
> So tell me why the government wants to see through my clothes?
Interestingly enough, people can already see through your clothes--at least, if you're wearing something fairly diaphanous or skintight already, like a swimsuit, or very light-colored clothing. And all they need is an older Sony video camera with NightShot before they put special filters on to prevent the trick from working, or a newer model with modifications...
Does anyone else recall the breif hysteria when Sony video camera owners realized that using NightShot during the day allowed them to record an image that saw partly through swimsuits and light clothes, and that became public? News broadcasts were definitely playing it up. Sony immediately announced that future video cameras would ship with filters to prevent such imagery...
IIRC, the problem (or "bonus") was that the IR light emitted by NightShot would travel through thin or light-colored clothing before being either reflected or re-emitted (can't recall exactly how it works...), so that when captured by the lens during daylight capturing, it let one "see" through some clothing.
There is in fact a whole genre of Internet pr0n dedicated to capturing unsuspecting females in swimsuits or thin white clothing with such cameras. The films have a greenish tinge, like looking through some Night Vision goggles, but do indeed show body outlines, nipples, pubic hair, etc.
Now, if that can be done with a HandyCam for a few hundred dollars, you know the government with its budget can get a lot more sophisticated and see a lot more clearly...
Chasing Amy
(We all chase Amy...)
"The more corrupt the state, the more numerous the laws"-Tacitus
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"
I wonder if no one noticed the little line on top that says, may 1995. If this technology is that old, how come it isnt on the market yet?
*sig*
If this is practically possible (which seems strange since it's been around for seven years now) and is not some hoax, then I could see a good use of this at airport security. It seems that it would be able to detect hidden weapons such as guns, xacto knives or knitting needles better than current systems. What would really be a problem would be the security personel getting to look at all the socialy taboo areas of the human body for free. ("Hey Jim, look at those ****, get a load of that fat freak"). I think a lot of people would object. I can see the legal battles already. In the end it might be of most use to some porno director to start a kinky new branch of the business.
If you can see through everything, what do you see?
Dave
Close, but totally wrong.
Microwave ovens use a frequency of 2.4 Ghz, which is no where near the Thz range.
This stuff could be called "super-infrared", it's more like optics than it is like radio.
I've had enough abrasive sigs. Kittens are cute and fuzzy.
NEW JERSEY - YOYODYNE LABS (NYSE: YO) has done it again! First they brought you watermelons that resist squashing, now they discover a visual technology that will allow humans to differentiate between many kinds of meat.
Using a special set of goggles, wearers are able to experience the part of the electromagnetic spectrum YO Labs is calling "visual light," or "V-light."
"It's amazing," says one test subject, "I've never been able to appreciate bacon for what it was. With these goggles, I can differentiate the fat layer from the meat layer!"
Scientists are saying that "V-light" technology will herald a new age. Perfect Tommy said, "It will effect a paradigm shift, the likes of which we've never seen! I know there are many concerns about privacy and stuff, but really, this technology is good. We only use our powers for good."
Privacy advocates are calling "V-light" immoral. "The ability for people to tell the difference between, say, bacon and corned beef, is a god-given right. But I don't want people to be able to just look into my windows and see me prance around naked with a bowl of jello," says Kent Torokvei.
But government officials are adamant: "Visual light is a new technology that will enable us to catch criminimables," President George W. Bush said. "With it, we can tell if a terrorist is wearing something trendy, or something not-so-trendy. If we pull back his shirt, we might even be able to see if he has a bomb strapped to his chest. My advisors tell me we might even be able to tell if criminals are black or white, which will aid our police officers in their policy of racial profiling!"
"I don't give a flying wahoo what the President says," Buckaroo Banzai, head of the Hong Kong Cavaliers, said in a recent interview. "The fact of the matter is, I'm sick of biting into a slice of bacon and finding it being mostly meat. I need my fat. We can give these goggles to the poor and the malnourished, and they can use it to find fat people to eat just by LOOKING at them!"
"Fat people are a delicious and nutritious meal. I realized that after seeing that unsquashable watermelons did nothing to do to rid the world of famine. They're easy to hunt, and they're easy to bait. This is much better than trying to smash open an unsquashable watermelon."
And what about T-waves?
"Terahertz waves? That thing sucks big donkey dong. The real genius is V-light. Not only can I see intimate details, but I believe the technology can be tuned to predict the future somewhat. Here. Take off your pants. Lemme tune my goggles. Ok, I can see your nuts, and I can also predict that you will never die of autoerotic asphyxiation."
Just wait unitl X10.com get's a hold of this technology!
There is no longer anything that can be done with computers that is nontrivial and clearly legal. -- Paul Phillips
Linux PDA of your choice: $400
802.11 or other wireless networking card: $150
TRay Camera springboard: $25,000
Being the first human with a tricorder AND the fact that it run Linux: Absolutely priceless.
My $0.02 will always be worth more than your â0.02, so
Telescopes like the James Clerk Maxwell Telescope (JCMT) and the Caltech Submillimeter Observatory (CSO) have been using these THz waves to do astronomical research for about 15 years.
THz waves are in the millimeter/submillimeter regime of the electromagnetic spectrum, placing them between the far-infrared and the radio.
Just like we use infrared light to look at things which are at roughly room temperature, we use submillimeter light - with wavelengths about 10 times longer - to look at things which are about ten times cooler, down to a few tens of Kelvin above absolute zero.
This includes solar system bodies, comets, and clouds of interstellar gas and dust - the birthplaces of new stars. Just like in the articles, we can use submillimeter waves to see through things that entirely block visible (optical) light.
This post is strictly my own opinion and not necessarily that of my employer.
These wavelengths have the rather ungainly "millimeter and submillimeter" label. There's "far-infrared" at about 100 microns, and this regime runs from there out to, well, about a millimeter. :-)
I am an astronomer who works with submillimeter wavelengths at the James Clerk Maxwell Telescope (JCMT). In this regime, we're really at the boundary between optics and radio. You can almost think of it as the boundary between whether you treat light as a wave or as a particle.
Some of our astronomical instruments are radio-style "heterodyne" receivers which treat the light as a wave and produce spectral line information (telling you what molecules are out there and what they're doing). It's a bit like sweeping a radio dial through a range of frequencies and marking the signal strength of all the stations.
Other detectors treat the light much more as a particle, just measuring the total amount of radiation falling onto a pixel. On the JCMT we have such an instrument called SCUBA (the Submillimeter Common User Bolometer Array). They're analogous to the CCDs used at optical and infrared wavelengths. I'm guessing that the work mentioned in the article refers to detectors of this type, but I could of course be wrong. :-)
This post is strictly my own opinion and not necessarily that of my employer.
That is, 550e15 hz. Light is around 550 petahertz.
Actually, the ATT article wasn't the best one to point to. Star Tiger's website gives the details outlined in the MSNBC/Space articles. Apparently, there are naturally occurring THz frequency waves emitted from "almost everything". ATT seem more interested in an active system similar to radar, with their studies focusing on looking at the reflectance and transmissive properties of various breakfast foods.