Regan D
Department of Psychology BSB, Center for Vision Research, York University, 4700 Keele Street, Ont., M3J 1P3, North York, Canada.
Vision Res. 2002 Oct;42(22):2479-84. doi: 10.1016/s0042-6989(02)00086-x.
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.
众所周知，当物体的水平相对视差适当变化时，大多数观察者会产生一种强烈的印象，即该物体正在靠近，并将在未来某个时刻与观察者相撞。在此，我推导出一个新的方程，即碰撞时间（TTC）近似于（ddelta/dt）/（d(2)delta/dt(2)）。该方程将碰撞时间与视网膜图像变量相关联，而无需知道接近物体的距离或速度。在这方面，新方程是著名的tau方程的双目等效形式。
