Source : Webster's Revised Unabridged Dictionary (1913)

Stereoscopy \Ste`re*os"co*py\, n.
   The art or science of using the stereoscope, or of
   constructing the instrument or the views used with it.

Source : WordNet®

stereoscopy
     n : three-dimensional vision produced by the fusion of two
         slightly different views of a scene on each retina [syn:
         {stereoscopic vision}]