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Passive millimeter wave imaging growing fast
The International Society for Optical Engineering ^ | 2000 | Yvonne Carts-Powell

Posted on 10/21/2004 1:57:36 PM PDT by theFIRMbss

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To: dartuser
AFRL?

Refer again to the blackbody curve ... there's not much out there in the mm wavelength realm, perhaps undetectable by 1980s technology. I guess what's "news" is that it isn't 1980 anymore, and that mm wave detection technology (along with most other electronic technologies) has improved significantly since then. IR has improved significantly since then as well.

In any case, the temperature and reflectivity of the objects in the buildings/cars scene varies ... Dark areas are probably shiny and reflecting the sky. Bright areas are warmer and emitting according to their temperature. In the man with the guns scene, he's emitting based on his skin temperature. The outside surface of the guns is cooler than his skin, so is emitting much less. Transmissivity of his clothes is more or less constant throughout the scene ... so the cold (dark) guns stand out against the bright (hot) body.

21 posted on 10/21/2004 3:18:12 PM PDT by ArrogantBustard
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To: theFIRMbss

Kewl...Isn't there a technology site. john huang 2 (?) had one. :|


22 posted on 10/21/2004 4:26:57 PM PDT by skinkinthegrass (Just because you're paranoid, doesn't mean they aren't out to get you :)
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To: Tallguy
I wonder if this type of sensing could negate stealth technology? Needless to say, we're heavily invested in stealth

Probably not, the range is not all that long as the frequencies are strongly absorbed in the atmosphere.

23 posted on 04/14/2005 8:56:50 PM PDT by El Gato (Activist Judges can twist the Constitution into anything they want ... or so they think.)
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