The Mantis Shrimp has eyes that are compound, like those of the dragonfly, although they have a far smaller number of ommatidia (about 10,000 per eye;) however, in the mantis shrimp each ommatidia row has a particular function. For example, some of them are used to detect light, others to detect color, etc.
Mantis shrimp have much better color vision than humans (their eyes having 12 types of color receptors, whereas humans have only three,) as well as ultraviolet, infrared and polarized light vision, thus having the most complex eyesight of any animal known. The eyes are located at the end of stalks, and can be moved independently from each other, rotating up to 70 degrees. Interestingly, the visual information is processed by the eyes themselves, not the brain.
Even more bizarre; each of the mantis shrimp’s eyes is divided in three sections allowing the creature to see objects with three different parts of the same eye. In other words, each eye has “trinocular vision” and complete depth perception, meaning that if a mantis shrimp lost an eye, its remaining eye would still be able to judge depth and distance as well as a human with his two eyes. Scientists are only starting to understand the mysteries of Stomatopod vision; for the moment, we can only imagine what the world really looks like to a mantis shrimp.
Photograph by Tim Laman