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The visual perception of three-dimensional length.

J F Norman·J T Todd·V J Perotti·J S Tittle
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Abstract

A set of 4 experiments evaluated observers' sensitivity to three-dimensional (3-D) length, using both discrimination and adjustment paradigms with computer-generated optical patterns and real objects viewed directly in a natural environment. Although observers were highly sensitive to small differences in two-dimensional length for line segments presented in the frontoparallel plane, their discrimination thresholds increased by an order of magnitude when the line segments were presented at random orientations in 3-D space. There were also large failures of constancy, such that the perception of 3-D length varied systematically with viewing distance, even under full-cue conditions.

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Computer-Aided DesignDepth PerceptionHumansMaleOptical IllusionsSize PerceptionJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.

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J F Norman, J T Todd, V J Perotti, J S Tittle. 1996. The visual perception of three-dimensional length.. https://doi.org/10.1037/%2F0096-1523.22.1.173

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