#$%^&*AU2017268552A120171221.pdf#####ABSTRACT An apparatus comprising: a plurality pixel units (107, 109) in a two dimensional array, each pixel unit comprising: a photo sensor (101) to receive the light, a micro electrode (103) to deliver a stimulus to neuron cells, and circuitry (105) to derive the stimulus from the light and drive the electrode, wherein the photo sensors, the micro electrodes and the circuitry are embedded within layers of material based on a common silicon substrate (501) including a semiconductor layer formed on a front surface within the silicon substrate, the photo sensors (507) and the circuitry embedded within a semiconductor layer and biocompatible layers (523) wrapping the device to bi-directionally protect the device and the tissues, wherein a common silicon substrate of the device is thinned to allow the device to be bendable in a two dimension manner, wherein the pixel units are configured to capture the light with a density of photo sensors higher than 250 per square millimeter. I 2OA-7227IDn7 A 7r A
