Factors affecting depth perception and comparison of depth perception measured by the three-rods test in monocular and binocular vision

PURPOSE: The purpose of this study was to explore the effects of factors affecting depth perception of moving objects using a modified three-rods test, which can be used at longer distances than the conventional one, and to compare differences in the results between binocular and monocular vision. METHODS: This study included 24 volunteers (10 women, 14 men; mean age, 35.2 years; standard deviation, 6.8 years; range, 22–56 years). We measured depth perception using a modified three-rods test under eight different conditions and investigated the factors affecting depth perception using a linear-effect model. RESULTS: The results identified test distance, binocularity, masking, and direction of movement as significant factors affecting depth perception of a moving object. CONCLUSIONS: The current study successfully determined factors affecting depth perception using the three-rods test with a moving object and the results should contribute to further clinical and social applications of the three-rods test.