Single chip CMOS image sensors for a retina implant system

Abstract

This work describes the architecture and realization of microelectronic components for a retina implant system that will provide visual sensations to patients with photoreceptor degeneration by applying electrostimulation of the intact retinal ganglion cell layer. Special circuitry has been developed for a fast single-chip CMOS image sensor system which provides high dynamic range of more than seven decades (without a mechanical shutter) corresponding to the performance of the human eye. This image sensor system is directly attachable to a digital filter and a signal processor that compute the so-called receptive-field function for generation of the stimulation data. These external components are wireless linked to an implanted flexible silicon multielectrode stimulator which generates electrical signals for electrostimulation of the intact ganglion cells. All components, including additional hardware for digital signal processing and wireless data and power transmission have been developed for fabrication using our in-house standard CMOS-technology.