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Infrared Webcam HOWTO
Geoff Johnson writes "Some of the Slashdot readers may be interested in this page I put together. It describes how to make an ordinary webcam see in the near infrared waveband."
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Well, and replace it with one to block visible light. But yes, that's about it.
I am trolling
http://homepage.ntlworld.com.nyud.net:8090/geoff.j ohnson2/2004-08-08.avi
You don't need to for 'night vision', which is what I expect most people will be interested in.
Full colour (maybe a tiny bit washed out because of the extra IR) during daylight, and at night switch on the IR light and you've got an IR camera.
Near IR isn't that interesting, except humans cant see it, what would be cool is if the chips could pickup far IR so you could see heat.
thank God the internet isn't a human right.
If you're lucky the webcam won't have an IR blocking filter.
You may want to check it with a remote (or just put your IR passing filter in front of it) before you take it apart.
Stop the world; I need to get off.
Lots of things work, you can easily buy a IR pass filter.
I I've used purple sweet wrappers in an IR remote control, and often the plastic in the housing is good enough to block most visible light but pass IR.
thank God the internet isn't a human right.
This was covered on slashdot a long time agao.
But yes, it can see through clothing to some extent.
What changed under Obama? Nothing Good
Cadillac's system was actually a Barium Strontium Titanate (BST) module, developed by Raytheon. It required a thermal differential in the scene from frame-to-frame to be able to see anything, and thus a "chopper" wheel (a rotating slotted disc) had to run in front of the detector. The picture would smear and was generally low-quality. The module used by Cadillac was also rather low resolution (160x120, I believe).
The alternative to BST is microbolometer technology, developed by Lockheed Martin / BAE Systems and others. A microbolometer array consists of vanadium-oxide bridges that vary their resistance when exposed to thermal radiation. The scene will occasionally need to be "shuttered" (i.e., zero all the pixels against the back of a shutter mechanism to cancel the thermal drift that creeps in over time.)
Unlike light-amp, true thermal imaging allows you to see in complete darkness. And unlike projected-IR, it isn't limited in range by any kind of IR-transmitter. And unlike either of those technologies, it allows you to very quickly find humans (or other mammals) in a scene, and it allows you to see where things used to be by the heat-shadow that they've left.