Fitting of brightness as a function of current amplitude in a visual prosthesis

摘要

To accurately represent a visual scene a visual prosthesis must convey luminance information across a range of brightness levels. To do this, the brightness of phosphenes produced by an individual electrode should scale appropriately with luminance, and the same luminance should produce equivalently bright phosphenes across the entire electrode array. Given that the function relating current to brightness varies across electrodes, it is necessary to develop a fitting procedure that will permit brightness to be equated across an entire array. The current invention describes a method of performing a brightness fitting that normalizes brightness across electrodes. The method determines a set of parameters that are stored in the subjects Video Configuration File—the look-up table that converts the video camera input to stimulation profiles for each electrode. One electrode would be specified as the standard. Brightness rating would be carried out on that electrode so“rating”as a function of current amplitude was known for that electrode.