hi,
I have a coffee table with the top being glass. I was wondering if there was anyway to use that glass to make a multitouch. (Instead of buying acrylic). For now i just want to make a multitouch without a projector and when i eventually get a projector, i will fit it in. I dont want the glass to be a waste. I was also wondering if instead of using ir leds in the side of the glass whether i could use a Ir light source below the surface( similar to microsoft surface).
Thanks,
Amateur777

amateur777 - 04 July 2007 03:03 AM

hi,
I have a coffee table with the top being glass. I was wondering if there was anyway to use that glass to make a multitouch. (Instead of buying acrylic). For now i just want to make a multitouch without a projector and when i eventually get a projector, i will fit it in. I dont want the glass to be a waste. I was also wondering if instead of using ir leds in the side of the glass whether i could use a Ir light source below the surface( similar to microsoft surface).
Thanks,
Amateur777

FTIR would obviously be a no go, rear illumination such as MS Surface might work. You could do some experiments by taping a bit of tracing paper on the backside of the glass an illuminate it with IR light. Also place a webcam to see if you can capture any blobs.

Yeah, like Falcon4ever said, this will work for rear illumination (like MS). There’s reading on the forum about it. Look for “Diffused Illumination.” If tracing paper doesn’t work under the glass, try it on top as I get better results with it on top.

thanks for the quick replies.
yeah i was wondering whether i could do it similar to m surface. I remember reading that normal light bulbs give off IR light. Could they be the IR Light source? If you put some photo negatives as an ir filter the light bulb should only give of ir light. Im kinda new to this and just trying out different ways (to find the cheapest).
thanks, Amateur777

Normal light should be fine as long as you’re not using a projector. The light will most likely interfere with the projectors beam.