- Cheapie webcam from Amazon.com (http://www.amazon.com/gp/product/B0015TJNEY) ($5-6)
- 1 or 2 (recommended) pieces of exposed film negatives (as visible light filters)
- Sharp craft knife ("X-ACTO knife")
- super glue (cyanoacrylate), or any glue will do
If you're lucky and find someone really nice at a photo place, they might give you exposed film negatives for free. To my knowledge, all this is is if you took a roll of film, pulled it out of the roll to expose it to light, then got the negatives of those. You might have some sitting around if you have old negatives... they're likely the dark pieces at the beginning of the negatives. Back in the days when we used film.
Step 1: Disassemble the Lens
Use the screwdriver (or screwdriver-like implement) to press in the "tabs" to remove the outer assembly.
Continue using your fingers to unscrew the inner assembly until it comes out.
Step 2: Remove Infrared Filter
1. Use your sharp knife to shave off the plastic holding down the corners of the IR filters.
2. Once the plastic is removed, you should be able to easily lift the filter out (using your knife)
Update: The webcams you get may vary (even if you bought it from the link I listed earlier). Different webcams may have been constructed slightly differently, and removing this IR filter may be easier or harder. Cross your fingers. :oP
Step 3: Insert and Glue Visible Light Filter
2. Plop the filters into the square, where the IR filter used to be.
3. Glue it down using your preferred method. (I dipped the tip of a paperclip in the glue, then scraped it onto the edge of the film. Do not squeeze super glue directly onto the film, as it'll probably be too much and flood over the whole thing. Super glue is tricky to work with. Use tiny amounts, and if that's not enough, use more. Or just use regular school glue. These filters won't be undergoing much load or stress.)
Step 4: Reassemble
Step 5: Test It Out
For lesson ideas, see Dan Burns' handout here: http://www.lghs.net/apps/classes/show_class.jsp?classREC_ID=398988 (the IR one near the bottom)
The topic of infrared itself isn't a California Science Content Standard, but I use it as a bridge to go from visible light to "invisible light", then expand it to the idea of a giant range of "invisible lights" known as the electromagnetic spectrum, which is specifically a standard. I have no evidence this approach is effective. :oP :o)