Arthropods are unique in possessing a compound eye, which results in their seeing a multiple image that is partially integrated in the brain.
A black hole, according to the general theory of relativity, is a region of space from which nothing, including light, can escape. It is the result of the deformation of spacetime caused by a very compact mass.square peg web
The simplest eyes, such as those in microorganisms, do nothing but detect whether the surroundings are light or dark, which is sufficient for the entrainment of circadian rhythms. From more complex eyes.