Compound eye of dragonfly. Macrophotograph of the compound eye of a dragonfly (species unidentified, order Odonata). The compound eyes of dragonflies consist of up to 30,000 individual facets called ommatidia. Each facet sends a signal to the brain, which then constructs a mosaic view of the world. The image lacks the detailed resolution of human sight but is good at detecting movements. Dragonflies have unusually