Optical signal and energy transmission for a retina implant

Presents the development of a signal and energy transmission technique for a retina implant. This implant, called retina stimulator (RS), is part of a system designed to provide artificial vision for blind persons suffering from retinal defects, especially retinitis pigmentosa (RP). The system consists of two parts, a retina encoder (RE) outside the eye and the RS implanted onto the retina. This RS is provided with digital signals and energy via free space optical transmission at data rates of 200 kbit/s together with electrical power of 5 mW, respectively. An array of photovoltaic cells (PVC) monolithically integrated with a photodiode is used as energy and signal receiver. A receiver circuit powered by the PVC-array is developed and manufactured. It transforms the output of the photodiode into TTL-compatible data suitable for further digital processing.