title: Binocular information about time to collision and time to passage.
abstract: It is well known that, when an object's horizontal relative disparity is changing appropriately, most observers report a compelling impression that the object is approaching and will collide with the observers at some future instant. Here I derive a new equation, namely TTC approximates (ddelta/dt)/(d(2)delta/dt(2)). This equation relates TTC to retinal image variables without involving a knowledge of the approaching object's distance or speed. In this respect the new equation is the binocular equivalent of the well-known equation for tau.
authors.affiliation: Department of Psychology BSB, Center for Vision Research, York University, 4700 Keele Street, Ont., M3J 1P3, North York, Canada. dregan@yorku.ca
authors.forename: D
authors.initials: D
authors.lastname: Regan
mesh_terms: D001334:Automobile Driving; D004215:Distance Perception / Q000502:physiology; D006801:Humans; D009039:Motion Perception / Q000502:physiology*; D013997:Time Factors; D015348:Vision, Binocular / Q000502:physiology*