I had this post queued up for some time (actually wanted to flesh it out a bit more), but this seems as good a time as any to post... maybe we could make this thread a general collection for experiences (the good and the bad) with touch screens / touch frames?
We've been building a fair number of interactive exhibits with Ventuz in the last two years. One of our biggest problems usually is the touch screen (or touch frame). So far I haven't seen one that I would heartily recommend to anyone without major caveats.
Usually we don't use prefabricated touch screens, but rather "roll our own" using LCD-Panes and adding APR(*)-Touch-Frames (from
http://www.elotouch.de ). Mixed experiences... usually OK for dual touch, but problems with a few models (list of particularly troublesome model/driver-combos may follow, still doing research). I actually suspect some of the problems somewhere in the communication between the touch-driver, Windows and Ventuz... we've had cases where touches wold register with 100% reliability in "naked" Windows, but in Ventuz only about a third of touches would be registered (even after tweaking tap/tap'n'hold-thresholds).
We built one exhibit using
http://www.visualplanet.biz capacitive "touchfoil"... not happy either. As before: more problems in Ventuz than plain Windows, also I don't like the quite visible pattern the foil adds to the monitor-pixel-grid.
By the way: one of the biggest problems with capacitive touch screens appears to be electrical interference, especially where multiple touch screens are in close vicinity... we recently created content for an exhibit at Frankfurt Motor Show (IAA) where the contractor for the touch screens (luckily not us!) had to rip out four huge seamlessly integrated capacitive touch frames and replace them with IR touch frames (no more even surface, the IR screens need a ~5-10 mm high border for the IR transmitter/receivers).
In one case we built a semi-spherical true multi-touch screen using rear projection, an IR camera, IR Diodes, thermoformed acrylic glass and CCV (
http://ccv.nuigroup.com/) -- so far the nicest and most reliable multi touch experience we created (unless the ambient light ist too much or you're using Ventuz < 3.06 in which case it goes kablooie on too many touch points
).
Colleagues of mine were very impressed recently at ICE/Amsterdam by a (demo) PSD-table from flatfrog (
http://flatfrog.com/technology )... anyone out there with some real-world experience?
Thanks,
squiggle
P.S.: There is a quite comprehensive overview of different touch technologies (as of 2010) available for free from the Fraunhofer Institute (in german only, you'll have to submit a valid e-mail address):
http://www.hci.iao.fraunhofer.de/publik ... -touch.jsp
P.P.S.: I'd also like to hear from the Ventuz-crew... posts like the following are always welcome
http://inside.ventuz.com/2010/08/coming ... ultitouch/
http://inside.ventuz.com/2011/02/touch-wood/
(*)
http://en.wikipedia.org/wiki/Touchscree ... ecognition