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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."
So tell me why the government wants to see through my clothes?
Wherever you go, there you are!
You mean they don't measure sea temperatures with lots of boats with thermometers as rudders?
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"
Trex Enterprises has had this for years. It's called "Passive Millimeter Sensing" and they have a product called the Passive Millimeter Camera which was doing this a while ago. Check out there web site www.trexenterprises.com
> 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*
Quoth the article:
Low-frequency versions of terahertz waves are known as millimeter waves, and they behave much like radio waves, Star Tiger engineers say. At higher frequencies, the terahertz waves straddle the border between radio and optical emissions.
Visible light has wavelengths up to around 750 Nanometers. Infrared has wavelengths extending (depending on who you ask) from there up to some number of micrometers.
At a frequency of 1 terrahertz, light has a wavelength of the speed of light (per second) / 1 trillion.
c per second is about 300 million meters.
300 million meters divided by 1 trillion is about 300 micrometers. A typical microwave oven uses a wavelength of about 100 micrometers. (The link has some other helpful info about spectrum, but also some typos.)
This IS microwave radiation.
I don't know why they've decided to start calling them "T-Waves." I'd geuss that they're gearing up to put them into airports, and that somebody decided that they don't want to call them "microwave cameras" so that people aren't afraid of being cooked somehow.
Incidentally, Microwave detection is not a new development; the Military has been using Microwave transmitters since the 70s. What is new about these newer cameras is their sensitivity/accuracy; previous generations of microwave cameras were not sensitive enough to image much of anything.
The good and new comes from no quarter where it is looked for, and is always something different from what is expected.
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
I thought we all hated windows! Damnit, now I'm confused.
Rod Taylor
The only way we'll know is if we start testing. As much as it sucks to be the victim of a sience device gone wrong, sometimes it's nessesary. When they were first developing x-rays, I highly doubt any person was even thinking of checking for the possibilities of cancer. They've probably check this sucker for obvious dangers, but the less obvious ones will just have to be tested in the real world.
As proof of my point, how would anyone in the world know that having a hair dryer could make you dumb enough to use one in a shower unless some moron did so. That's why we have a warning lable.
T Money
World Domination with a plastic spoon since 1984
Windows ain't easy to install (without all the gibberish) and it takes a lot more than a minute...
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
(* Being the first human with a tricorder AND the fact that it run Linux: Absolutely priceless. *)
I am surprised you are the only one who mentioned "tricorder" (at least in a text search). The description sounds much more like a tricorder (composition analyzer) than something to see thru girls' clothes. Excerpt:
"AT&T Bell Laboratories scientists have demonstrated an innovative imaging system that uses optics and electronics to "see" the composition of objects - just as X-rays "see through" materials to reveal denser elements inside. They can show, for example, how much fat is in a slice of bacon, how much water is in a leaf, and whether a package holds a banana or a bomb - without touching it."
We already have X-rays to see thru things, so the uniqueness here is the "point and analyze" capabilities.
(Unless perhaps if it can see thru things without having the emitter on one side and the receiver on the other, which is what X-rays usually require in practice.)
Table-ized A.I.
citeseer is a great thing, and this is a great T-wave overview article:
"Recent Advances in Terahertz Imaging", Mittleman et al
How quickly we forget. Snow Crash had LOTS of plot elements that were all about millimeter-wave radar. It's how the robo-dog saw the world, for heaven's sake!
:-)
"never heard of this before" -- sheesh... kids these days
Because we all know that the military figured out how to read your license plate looking straight down on your car.
The thing about satellites is they really can't do much more than look almost straight down.
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.
That is, 550e15 hz. Light is around 550 petahertz.
Hey!
You can't suggest installing Windows on Slashdot!
I'm old enough to remember when discussions on Slashdot were well informed.
Now the AT&T Bell Labs article, on the other hand, says nothing about objects emitting anything, it talks exclusively about generating T-rays from the recording device, and measuring their effects, similar to X-Rays.
Are these articles talking about the same technology? Seems to be described quite differently.
"Mind, as manifested by the capacity to make choices, is to some extent present in every electron." -Freeman Dyson
Check out Star Tiger's site, which includes info about the technology discussed in the MSNBC and Space articles. While the AT&T link is interesting, it's a slightly different approach to THz wave applications than what Star Tiger's doing.