The effects of perceived depth of a fixation stimulus on peripheral depth perception while observing stereoscopic images

Abstract

The present study investigated the effects of perceived depth of a fixation stimulus on peripheral depth perception while convergence and accommodation produced inconsistent depth cues. We presented a standard stimulus at the central visual field and a comparison stimulus at the peripheral visual field. Observers judged whether perceived depth of a comparison stimulus is located or not on the fronto-parallel plane at a standard stimulus while fixating it. The convergence of a standard stimulus was varied as an independent variable. We measured points of subjective equality of perceived depth between the standard and comparison stimuli. Perceived depth of a comparison stimulus was located closer as the eccentricity increased. This shift of perceived depth was smaller when the convergence angle was large. This result suggests that the effects of accommodation on depth perception are comparatively larger in peripheral visual field while convergence is the main depth cue in the central visual field.