Seen here is the Bayer pattern on a small video CCD. The repeating pattern is:
This photo was quite difficult to take for several reasons:
-CCDs are opaque, so conventional pass-through light microscopy wouldn't work.
-Lighting the microlenses required a ton of light from several directions.
-Focusing the microlenses correctly at 600X was insanely difficult.
-Getting the color to show up properly was very tricky (white balancing was critical).