
Make an IR camera! Using a webcam, removing the lens and replacing it with material from photo negatives, it should block visible light and only let IR through. I haven’t tried this yet, but I think I will. If I get this working I think I’ll put it on my robot and see what types of things it does. I wonder if IR signals from my TV remote will show up.
another way is to cover the lens with the magnetic disk from a 3.5 floppy disc (zip discs work too, but block out more light).
its effective and you can still use the camera for other purposes when ir isn’t needed.
Ooooh… Nice.
At some point I read about researchers at Carnegie Mellon University’s Robotics Institute who wanted to watch how often drivers were blinking as a measure of their drowsiness. The solution involved using two infrared cameras, each keyed to a different wavelength of infrared light–one color that would be absorbed by the fluid in a human eye and one that would be reflected. By subtracting the two images, you get two dots where the person’s eyes are (or none at all if he or she is blinking).
I’m wondering if you could do something similar–use a regular webcam and your IR-hacked webcam and maybe subtract the images, or XOR them or AND them or something. Can’t think of any applications off the top of my head, but there could be something really neat hiding here. Maybe a nifty heads-up display? Could have some medical applications, if you can overlay IR video with visible spectrum video.
Regading the IR visibility from a remote – I noticed on an old Sony 8mm camcorder that the TV remote ir was very visible when filmed. You could even make out a flash pattern for the different commands. “Night vision” mode was not available on this model but I’ve read that it was only a matter of removing the IR filter – providing for both IR and visilble light sensitivity. -phog
A couple of layers of congo blue makes a great IR-pass filter. I use these on my own B&W CCD cameras to make low-cost IR converter scopes.
You may have noticed that page is now a 404. The new URL for the IR webcam site is
http://www.hoagieshouse.com/IR
By the way, magnetic disk does work but isn’t nearly as efficient as film negatives.
You can see a video showing the whole process here:
http://www.metacafe.com/watch/385098/trasform_your_webcam_into_an_infrared_cam/
(with nice examples of use at the end!)