Depth Perception Apparatus

This device is the modern day equivalent of the ‘Three Needle Experiment’ designed by Helmholtz (1856-1866). The experiment was then refined in 1919 by Howard and used two rods instead of three and became known as the Howard-Dolman apparatus and was used to screen potential aviators for poor stereopsis. The present apparatus has been further enhanced by enclosing the rods in a housing and providing a uniform and diffused lighting system. It is the task of the participant to make depth discriminations on the basis of binocular or monocular cues alone.