A Spatial Resolution Measure of Cutaneous Vision

An experiment was designed to measure the spatial resolution of a visual prosthetic. Blind subjects were instructed to identify from tactile stimulation the orientation of grated targets of specific spatial frequencies. The bandwidth of the probability of correct detection of orientation versus the spatial frequency is taken as a measure of the system resolution. For a 20° field of view, the equivalent visual acuity of this system is 20/4820.