Project dimensions

Since we've decided on a projector to use with the project, we now have concrete measurements on the projector size, the throw distance of the projector, and the screen size.  These dimensions are illustrated in this diagram:

The surface of the table will be about 3 feet off the ground, around waist level.  This should be a comfortable height for people to interact with the table while standing.  It should also be low enough for people to be able to interact with it sitting down and for shorter users to interact with it.

I used an online tool from Projector Central to calculate what screen sizes we can use with the given throw distance. The screen size (33" x 24.75") is one of the smallest screen sizes possible with the given projector, but is still relatively large (imagine a 40" TV).  The screen size also represents the projector's native aspect ratio of 4:3.  Finally, I made sure that the camera we buy can still see the entire screen from underneath for infrared blob tracking purposes.  The M12 Infrared Web Cam from EnvironmentalLights.com can easily see the entire surface with a 73 degree lens even if the camera is mounted 12" above the bottom of the touchscreen case.

Please let me know if you see any problems with this design, as I will be ordering the first round of hardware very soon!  I'm really excited to start the physical construction!