Interactive Multitouch Display

Step 9: Framing support

Last but not least, build some framing to support the screen. I started from a coffe table frame as a base and a couple wood planks to get the screen up in the air. The exact geometry is dependent on the optics of your projector. The one I borrowed wouldn't focus at close distances so it was necessary to have the light follow a longer path, bouncing off the mirror and back up onto the display. The angle of the display surface matches that of the projector (angle of incidence = angle of reflectance) in order to minimize keystone distortion.

Comments

[junior2387]

The sheet of paper.. that goes on top of the acrylic glass right? and if it does, do you put some kind of protector on the paper so it doesnt rip when using it.. or is it just the paper glued on to the glass... and u just touch the paper and thats it?

[squiggy2]

sorry if this reply is too late (if you're impatient and can't wait a year and a bit for info) but for anyone alse wondering the same question...

In this rig the diffuser (tracing paper) is placed UNDER the acrylic touch-screen, sandwiched between it and another sheet of acrylic see step 6.

I have seen other rigs where a sheet of tracing paper is thinly smeared with silicone sealant and placed ontop of the touch-screen. this eliminates the need for a second sheet of acrylic, and the 'ghosting' associated with two sheets, but as junior mentioned, it is vulnerable to ripping. plus it has a funny paper feeling instead of smooth, futuristc acrylic.