So I had this idea to make my photodiode matrix more useful than for a touch screen.
I have seen ideas around for an Arduino controlled CNC machine. The only successful one I have seen is RepRap.
However, something I thought would be really cool, is to make the CNC also a 3D scanner.
To start simple the cutting side would be a 3 axis router. I’d like to use a Porter-Cable or something nice with which metal (at least aluminum) could be cut.
The scanner could be done a number of ways.
One way would be to angle a laser so that it reflects a line onto the object and sensors detect the intensity of the light while the object rotates.
Another way would be to surround the entire working space with an laser diode matrix each side could be scanned while the opposing side emits light.
I would assume that the rotating idea would have better results, but would be slower. Where as the matrices would be much faster yet less accurate.