A research team at Stanford University have created a unique photovoltaic chip – a Retinal Prosthesis – that will act as a solar cell array and provide partial vision for people who suffer from degradation in their photoreceptor cells. This chip not only generates power but it passes image data through to a processing retinal chip and on to the brain to be processed.
Placed behind the retina, this amazing system includes a goggle mounted video camera that captures the image, a pocket PC to process it in real time, and a bright, LCD infrared screen. The screen produces sufficient light to enter the eye and charge the solar cell array. The tiny 3mm (0.118″) wide chip has 3 layers, each of which has has 3 photovoltaic cells of three different sizes and is flexibly mounted on the retina using small 300 nanometer (0.0003mm) thick silicon posts.
It sounds like something out of a sci-fi movie, but it’s for real. This photovoltaic system gives the wearer 20/100 vision – not strong enough to drive but enough to see and recognize faces and read large print. What a fantastic breakthrough for those who’ve been without sight!
We are developing an optical system for a parallel delivery of information and energy to tens of thousands of pixels in the implant. This system permits normal eye scanning to observe a large field of view, as opposed to “hard wiring” of a video camera to the retinal stimulating array using a single emitter-receiver link.