Figure 2.

Scanning electron micrographs (SEM) of the hexagonal photovoltaic arrays with 55 μm pixels. (a) The whole implant of 1 mm in width, containing 250 pixels. The array was placed on top of the RPE for scale. (b) Higher magnification of the implant demonstrates relative sizes of the central active electrode [1] and circumferential return electrode [2] in flat pixels. The active electrode is 14 μm in diameter, and return electrodes are 9 μm wide. (c) Similar array with pillar electrodes. (d) Image of a single pillar electrode with a SIROF-coated cap. The pillar is 10 μm in height, with a cap width of 14 μm and stem width of 10 μm.