View Full Version : IR Filter (Ultrasonic too)

04-18-2008, 11:35 AM
I desire to build an electronics enclosure for my bot. Now, I would really like to make aesthetics somewhat a priority, if possible.

To that end, I am looking for something to place in front of Sharp IR sensors, to hide the sensor behind. Ideally, whatever it is should be an opaque black in the visible spectrum to prevent someone seeing the sensor. The material should be stiff enough to prevent a mild impact, but thin enough to bend around a curve.

Does anyone have any suggestions for what type of material I should be looking for? (and please, I am not interested in developed color film if that is what you are going to suggest)

Also, the same question for ultrasonics (Daventech SRF series). Anyone know of a material or something that is black but doesn't really block the ultrasonic functioning?


04-18-2008, 11:46 AM
Not very specific, but just to chime in, I'd do a search for ir bandpass filter

One of the first promising links to turn up was: http://www.maxmax.com/aXNiteFilters.htm

X-Nite Infrared filters block all visible light letting only infrared light pass. Cutoff is 630nm, 665nm, 715nm, 780nm, 830nm, 850nm and 1000nm. These filters are for use on cameras that are infrared sensitive. Filters are constructed of optical precision ground and polished glass. They appear completely black to the human eye. If you hold the 830nm and 850nm filter up to a bright light, you will see the light filament faintly. If you hold the 1000nm filter to a bright light, the filter will appear completely opaque."

Not cheap from this seller, but certainly that means someone else is. Shopping time! My favorite activity! :D

04-29-2008, 05:19 PM
For the ultrasonic sensors, you could maybe fashion a kind of speaker cover for them using sound transparent fabrics. I found some doing a quick Google search here: http://www.acousticalsolutions.com/products/fabrics/index.asp

I'm not 100% sure if they are transparent to ultrasonic frequencies of sound, but I guess it's worth a look!