Insect eyes may be tiny but they belong to a “remarkably sophisticated class of imaging systems”. They have compound eyes, made up of hundreds or thousands of optical units or facets. Considered as optical systems, these facets are simpler than the vertebrate eye design because there are no moving parts to focus the light.
“In the case of the ‘apposition’ eye of daylight insects, each facet is optically isolated from its neighbour and equipped with its own lens and set of photoreceptors. Because each facet accepts photons from only a small angle in space, the light sensitivity of apposition eyes is rather low and the spatial resolution is limited by the number of facets that can be packed on to the small head of the insect. However, apposition eyes provide their bearer with a panoramic view of the world as well as with an infinite depth of field, without the need to adjust the focal length of the individual lenses.” (Borst & Plett, 2013, 47)
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We should note that arthropod eye designs do not conform to the cobbled-together architecture that is associated with evolutionary tinkering. The driver for biomimetics research is the recognition of exquisite design that extends and inspires human creativity. Exquisite design is the hallmark of an intelligent agent. [. . .]
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