Patent ID: 8892211

Claim:
A method for electrically stimulating a retina of an eye to induce visual perception, said method comprising the steps of: placing an electrode within the eye in proximity to a retinal ganglion cell (RGC) layer; and applying a biphasic, asymmetrical, charge-balanced waveform to at least a portion of the RGC layer, said biphasic, asymmetrical, charge-balanced waveform comprising: a pre-pulse phase having a first polarity, a sub-threshold first amplitude, and a first duration to change the excitability of at least one cell related to the at least the portion of the RGC layer; and a stimulation-pulse phase following the pre-pulse phase having a second polarity opposite the first polarity, a supra-threshold second amplitude, and a second duration less than the first duration to induce visual perception.