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  #1  
Old 06-03-2009, 11:39 PM
the first supraliminal the first supraliminal is offline
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Can microwaves be used to make x-ray photgraphs?

Since the rays penetrate, could you, say, place a small chicken on a an x-ray film carrier, turn on the microwave for a second, and develop a picture of the bones?
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  #2  
Old 06-03-2009, 11:42 PM
the first supraliminal the first supraliminal is offline
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:sigh: This was meant to be a GQ question.
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Old 06-04-2009, 08:22 AM
fluiddruid fluiddruid is offline
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Off to GQ, but I really like the sounds of this X-ray microwave game.
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Old 06-04-2009, 08:45 AM
Machine Elf Machine Elf is online now
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http://www.fastcompany.com/magazine/...ve-camera.html
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Old 06-04-2009, 08:48 AM
Q.E.D. Q.E.D. is offline
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Not likely. One of the reasons is that microwaves in a consumer oven have a wavelength that is very long compared to the sort of structures you want to observe which means you'd only see indistinct blurs. This is in addition to the unfortunate fact that films are not sensitive to radio waves (good for photographers, since radio is everywhere, but bad for your hypothetical experiments) to any significant degree.

Last edited by Q.E.D.; 06-04-2009 at 08:48 AM.
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  #6  
Old 06-04-2009, 01:23 PM
the first supraliminal the first supraliminal is offline
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Quote:
Originally Posted by Joe Frickin Friday View Post
http://www.fastcompany.com/magazine/...ve-camera.html
"Walleye's Microwave Camera Brings X-ray Vision Home "
WOW !
I will surely buy one of those microwave wall scanners when they are available.
I'm in construction, specializing in restoring old buildings, and finding where the pipes and wires are hidden can often save us an elaborate and lengthy exploration with test holes and "fishing tapes".

I actually had that sort of application in mind when I asked the question. Don't really care about chicken bones, ha ha.
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Old 06-04-2009, 01:24 PM
lazybratsche lazybratsche is online now
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Microwaves are also absorbed and therefore blocked by water. This is what makes them so useful for heating up food. The flipside is that they only will penetrate a few cm -- the wavelength -- through an object. A person would be completely opaque to microwaves.
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Old 06-04-2009, 01:35 PM
bouv bouv is offline
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Quote:
Originally Posted by Joe Frickin Friday View Post
I suspect that doesn't really use microwaves, but instead terahertz waves. (which are pretty close to microwaves in the electromagnetic spectrum.)

Terahertz imaging is one of the 'next big things,' in imaging. It produces images similar to X-ray images, but it's non-ionizing radiation, like MRIs, so there's no worry about it causing radiation sickness or cancer.

However, unlike X-rays, and similar to microwaves, they are easily absorbed by water, so they can't penetrate very far into tissue. But it works great for walls, since there isn't much water in them. But they are being looked at for security reasons, since they go through clothing just fine but are stopped by metal.
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Old 06-04-2009, 01:45 PM
the first supraliminal the first supraliminal is offline
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Their web page says "The Walleye technology is based on the field of long wavelength imaging systems, in particular, millimeter wave imaging systems" http://www.walleyetechnologies.com/technology.html
Although, now that I read it, millimeters aren't all that long. Oh, well, the details can be left to the engineers.

Last edited by the first supraliminal; 06-04-2009 at 01:47 PM.
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Old 06-04-2009, 01:51 PM
Q.E.D. Q.E.D. is offline
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Originally Posted by lazybratsche View Post
The flipside is that they only will penetrate a few cm -- the wavelength -- through an object. A person would be completely opaque to microwaves.
Incorrect. The depth of penetration (or more accurately, the power attentuation factor with increasing depth) and microwave wavelength are only very loosely correlated. More important is the absorbtion spectrum of the object being irradiated and the total power density being applied. If you apply a lot of microwave power, you can get readable levels of signal through a human body; apply a LOT of power and you can read a signal through an elephant. The point is there is no fixed penetration depth beyone which no energy will pass.
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Old 06-04-2009, 02:15 PM
bouv bouv is offline
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[quote=Q.E.D.;11211439 If you apply a lot of microwave power, you can get readable levels of signal through a human body; apply a LOT of power and you can read a signal through an elephant. The point is there is no fixed penetration depth beyone which no energy will pass.[/QUOTE]

But won't putting in more power be more likely to...umm...cook the person? (Or elephant?) Though I suppose you can use s slightly different wavelength of the microwaves that are so attenuated to water, right?
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Old 06-04-2009, 03:31 PM
PatriotGrrrl PatriotGrrrl is offline
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Quote:
Originally Posted by the first supraliminal View Post
Their web page says "The Walleye technology is based on the field of long wavelength imaging systems, in particular, millimeter wave imaging systems" http://www.walleyetechnologies.com/technology.html
Although, now that I read it, millimeters aren't all that long.
Compared to light or x-ray wavelengths they are!
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  #13  
Old 06-05-2009, 02:12 AM
dtilque dtilque is offline
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Quote:
Originally Posted by bouv View Post
But won't putting in more power be more likely to...umm...cook the person? (Or elephant?) Though I suppose you can use s slightly different wavelength of the microwaves that are so attenuated to water, right?
The near side (closest to the source of microwaves) will be cooked pretty good; the other side hardly at all.

But contrary to popular belief, microwave ovens are not tuned to a special frequency that is especially absorbed by water. Water will absorb pretty much all microwave frequencies fairly well: How a Microwave Oven works
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