Design of embedded image based electrical trans-corneal stimulator

Once the human optical system stops working by different causes, it is usual to look for a possible cure based on optometric methodology. Visual prosthesis may be an option, especially when the optical nerve has not been damaged. One alternative to develop such prosthesis is to use an electrical transcorneal stimulator. Some recent papers have applied the cerebral plastic concept to justify why a repeated electrical stimulation can help blind (by an optical defect) patients to give a new reinterpretation of the reality. This paper reports the development of a particular electrical stimulator for the transcorneal area. Indeed, this device has embedded software used to treat the image captured by a CMOS camera, to produce the image segmentation throughout a set of polygons and to regulate the signal amplitude. The waveform was selected from the signals forms obtained in a regular retinographic study. The system has been tested off-line showing a good correspondence with the theoretical proposal. Ex-vivo tests also have been developed to analyze the tissue response using the signals produced by the stimulator.