In college, I solved a problem related to CCD cell arrangement in digital cameras. Artifacts were found at the boundary between light and dark areas of HDR images. In most CCD arrays, there are 3 cells per pixel (one for each color channel). The cells are arranged close together in clusters of 3. The difference in position between cells introduce errors in the captured image. To deal with this, I wrote a filter that corrects the issue. See a visualization below.