I’m a 19 years old pupil from Bavaria, Germany and own the multitouch-project at sourceforge. There I want to host my (and maybe other peoples?) multitouch-software.

As can also be read on the projects website, I came to the final run at a (at least here) well known technology-competition for pupils/studends under 21.

Since I started the project well before nuigroups founding (and before other project videos could be found on youtube or somewhere. Indeed there were only 300k google hits for “jeff han” :D) I don’t use touchlib but created my own Linux/OpenGL/C++-based framework that suits at least for my purposes.

As soon as I have wrestled with those video editing programs available for linux (and cinelerra stops crashing) I will release more videos, watch the website if interested.

jo pascal, sounds interesting to do some sharing on the software part, we have touchlib on a google server, but lately we have discussed that we wanted a central place for all our software projects, you should drop by on irc, so we can have a chat about it

your site looks nice btw

Looking at your screenshots, it looks like you are using a compliant surface rather than touching the bare acrylic, what have you used for this? (are you using a jeff han FTIR style setup?)

No, there is no compliant surface, its a three-layered system: there is a 10mm Makrolon surface (just for support), where I laid thin paper (that one used for packaging sandwiches) onto as a back-projection screen and on top there is a 4mm surface of cheap transparent stuff (so cheap indeed that I could not tell what it’s made of) lit by 48 infrared LEDs (I used SMD with flat heads, so I didn’t have to do great engineering work for fastening on the surface but just taped them to it) from all edges.
So I’m touching the bare surface, but with wet hands, as Jeff Han seemed to do in the first demos, too (he fingered around in his pockets?!)
The thing is, I never read his paper (don’t think it was out when I first saw his website? dunno...) as I am no member of ACM…
But somebody told me about producing a compliant surface by wetting the acrylic with alcohol (methanol/ethanol depends...) and putting thick paper onto it. At the time I did not try it really, but only with a small piece of paper and it does not work too well as it produces the effect always (but it seems that the alcohol draws back to the edges of the paper leaving a very thin film in the center that does not trigger the effect without the user pressing.)

Image below is just for better visualisation

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| | Transparent material (4 mm)
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| | Rear-Projection screen (thin paper)
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| | Makrolon (10 mm)
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Makrolon is Polycarbonate.