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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."
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
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.
Nothing that the public see's is any sort of really new development. My father once had a very good friend in the military, on the intelligence side of things, and he once made a comment about just how far ahead the military is sometimes. He said take state-of-the-art for consumers, and multiply it by about 10. That's state of the art for government. Believe it when theytell you they could pick your licence plate with a satilite long before you knew they could.
T Money
World Domination with a plastic spoon since 1984
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.
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.