The reason I ask is because I was planning on using a rear projection screen that is invisible to infrared, so I probably wouldn’t need the coupling.  Does anyone have any experience with this?

Thanks

Hey Garrett,
Yeah, you need some sort of compliant surface for better coupling.  I found that, as others have mentioned, it all depends on your skin when using bare acrylic.  I have dry hands so dragging my finger made it really hard to see the response on my screen.  When I licked my fingers though (hehe… gross… I know) my finger blobs were bright white.  So… you could forego a compliant surface, you’ll just have to put a note that says “please lick fingers before using multitouch table”

haha, thanks.