Figure 1

Retinal implants used for the drawing task. (A) Argus I electrode array (4 × 4 electrodes of 260 μm and 520 μm diameter arranged in a checkerboard pattern). (B) Argus I subject drawings on a grid screen were captured by an external camera and recorded to a video file. (C) Video files were analyzed offline by tracking the location of the fingertip frame-by-frame and by translating the drawings to a binary image. (D) Argus II electrode array (6 × 10 electrodes of 200 μm diameter). (E) Argus II subject drawings were recorded by a touch screen monitor. (F) Subject drawings were translated to a binary image. Shapes were closed by automatically connecting the first and last tracked fingertip location, after which a floodfill was applied.