Vision stereopsis

Dimenhydrinate altered color discrimination, night vision, reaction time, and stereopsis in healthy volunteers (1). 

There are many ways to measure vision. Visual acuity is the most common one. Other familiar ones include color vision, and visual field. Less common measures that may be more closely associated with the visual needs in driving include dynamic visual acuity, visual acuity in reduced illumination and under the presence of glare, contrast sensitivity, stereopsis (the ability to see depth of field with the aid of two eyes), and motion detection (the ability to distinguish very slow movement from lack of movement). The relevance of all of these functions for driving has been evaluated, and each of these functions and the evidence for their relevance is discussed below. 

Howard, I.P., Rogers, B.J. Binocular vision and stereopsis, p. 736. Oxford University Press, Oxford (1995)... 

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