How Do Spiders Eyes Work?
WouterSpiders have eyes that are unique to them. Their eyes allow them to see in a wide variety of directions. They also detect motion, vibrations, and different distances.
The main set of spider eyes, called principal eyes, have retinas at the back of two long tubes. Each lens focuses light onto a specific part of the retina. This allows the principal eyes to track an image. However, spiders need more than one pair of eyes to see a full field of vision.
A secondary set of eyes helps the principal eyes to determine distances and track the movement of prey. The secondary eyes also act as motion analyzers. Some of the secondary eyes have retroreflector tissue layer.
Jumping spiders have a very different kind of vision. They use a set of small eyes on the front of their face, and a larger set on the sides. These are used to detect color and motion.
Scientists are curious about how these eyes work. Researchers have dissected the eyes of jumping spiders to better understand the structure of their eyes. It turns out that the eyes of some species have pigments that filter UV and red light, and other color receptors.
In addition to the primary and secondary eyes, jumping spiders have two pairs of side-of-head eyes that are used to detect motion. Researchers have already developed depth sensors that mimic the ability of these eyes. Whether they can help robots in an unfamiliar environment is another question.
