the "screen" looks great, it's a neat idea, but with only a 0.05inch of precision it is useless... wonder what kind of sensor could be used to improve this...
edit: seems there's two row of interleaved pins, resulting in 0.05inch and not 0.1... still not enough in my opinion...
With only 3 numerical characters on the 'display' the best precision can only be 0.1 unless it rounds which would be pointless, or it is a higher precision at lower values.
You can also get obscure pin headers at 1mm spacing which he may be using because I doubt that you would ever be counting 22.1 inches on a ruler that size...
Mowcius