Photovoltaic retinal prosthesis: system view Video camera Image processor Infrared (900 nm) image projection system in video goggles Palanker Lab, Stanford U. Pulsed Near-Infrared Image Projection Processed image on LCD pulsed IR illumination Subretinal photodiode array NIR (900nm) beam IR Image on the retina Palanker Lab, Stanford U. Operation of Subretinal Photovoltaic Prosthesis 100 m Inner Nuclear Layer Ganglion cell layer axons 900 nm light Neural signals Subretinal Photovoltaic Array 70 m pixels, 5 m trenches RPE Palanker Lab, Stanford U. Advantages of the photovoltaic approach Parallel delivery of information to all pixels - scalable to thousands of pixels in the implant Maintains natural link between eye movements and visual information Adjustable image processing Operates at any ambient illumination conditions Simplified surgery Modular design: implants can be added to expand the field of view