Related Experiment Video
Updated: Aug 13, 2026

Measuring Sensitivity to Viewpoint Change with and without Stereoscopic Cues
Published on: December 4, 2013
Stereoscopic acuity and observation distance
Mark F Bradshaw1, Andrew Glennerster
1Department of Psychology, School of Human Sciences, University of Surrey, Guildford GU2 7XH, UK.
Abstract:
The amount of depth perceived from a fixed pattern of horizontal disparities varies with viewing distance. We investigated whether thresholds for discriminating stereoscopic corrugations at a range of spatial frequencies were also affected by viewing distance or whether they were determined solely by the angular disparity in the stimulus prior to scaling. Although thresholds were found to be determined primarily by disparity over a broad range of viewing distances, they were on average a factor of two higher at the shortest viewing distance (28.5 cm) than at larger viewing distances (57 to 450 cm). We found the same pattern of results when subjects' accommodation was arranged to be the same at all viewing distances. The change in thresholds at close distances is in the direction expected if subjects' performance is limited by a minimum perceived depth.
Related Concept Videos
Depth Perception and Spatial Vision
Focusing of Light in the Eye
Influence of Earth's Curvature and Atmospheric Refraction on Leveling
Imaging Biological Samples with Optical Microscopy
In optical microscopy, the specimen to be viewed is placed on a glass slide and clipped on the stage...
Properties of Enantiomers and Optical Activity
Anatomy of the Eyeball
