[Dynamic stereoscopy and parallactoscopy and their importance for the 3-dimensional perception of moving objects]

The three-dimensional perception of moving objects plays an important role in professional and everyday tasks. Nevertheless, to date it has remained relatively unnoticed in the practice of ophthalmological and occupational medicine, although in 1984 the WHO also recommended testing dynamic vision. To determine dynamic stereoscopic visual acuity, the binocular prism rotation device was constructed and to determine dynamic parallactoscopy, the parallactoscopometer. The visual acuity found via dynamic stereoscopy decreased relatively quickly with increasing velocity (n = 103) and differed from stereoscopy determined at rest. Dynamic stereoscopy led to very precise fine spatial orientation, but it failed with average velocities; dynamic parallactoscopy had coarser visual powers, but it was relatively independent of speed and thus rendered essentially better spatial orientation possible at rapid velocities. It is possible that at slow pedestrian speed the two were equal. Under much-reduced light densities and reduced visual acuities, dynamic parallactoscopy remained intact in contrast to dynamic stereoscopy.