drone fly, compound eye

Drawing of a grey drone fly(꽃등에) published in Robert Hooke's Micrographia of 1665.

자료:  http://www.freebase.com/view/wikipedia/images/en_id/5902137

A compound eye is a visual organ found in arthropods such as insects and crustaceans. It may consist of thousands of ommatidia which are tiny independent photoreception units that consist of a cornea, lens, and photoreceptor cells which distinguish brightness and color. The image perceived by the arthropod is a combination of inputs from the numerous ommatidia, which are oriented to point in slightly different directions. Compared with single-aperture eyes, compound eyes have poor image resolution; however, they possess a very large view angle and the ability to detect fast movement and, in some cases, the polarization of light. Compound eyes are typically classified as either apposition eyes, that form multiple inverted images, or superposition eyes, that form a single erect image. Apposition eyes can be divided into two groups. The typical apposition eye has a lens focusing light from one direction on the rhabdom, while light from other directions is absorbed by the dark wall of the... less

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자료: Wikipedia, http://en.wikipedia.org/wiki/index.html?curid=355765#Compound_eyes

Compound eyes

A compound eye may consist of thousands of individual photoreception units. The image perceived is a combination of inputs from the numerous ommatidia (individual "eye units"), which are located on a convex surface, thus pointing in slightly different directions. Compared with simple eyes, compound eyes possess a very large view angle, and can detect fast movement and, in some cases, the polarization of light.^[12] Because the individual lenses are so small, the effects of diffraction impose a limit on the possible resolution that can be obtained. This can only be countered by increasing lens size and number — to see with a resolution comparable to our simple eyes, humans would require compound eyes which would each reach the size of their head.

Compound eyes fall into two groups: apposition eyes, which form multiple inverted images, and superposition eyes, which form a single erect image.^[13] Compound eyes are common in arthropods, and are also present in annelids and some bivalved molluscs.^[14]

Compound eyes, in arthropods at least, grow at their margins by the addition of new ommatidia.^[15]