Editing Eye (section)

====Other====
Another kind of compound eye, found in males of Order [[Strepsiptera]], employs a series of simple eyes—eyes having one opening that provides light for an entire image-forming retina. Several of these ''eyelets'' together form the strepsipteran compound eye, which is similar to the 'schizochroal' compound eyes of some [[trilobites]].<ref>{{Cite journal|last1=Horváth|first1=Gábor|last2=Clarkson|first2=Euan N.K.|year=1997|title=Survey of modern counterparts of schizochroal trilobite eyes: Structural and functional similarities and differences|journal=Historical Biology|volume=12|issue=3–4|doi=10.1080/08912969709386565|pages=229–263|bibcode=1997HBio...12..229H }}</ref> Because each eyelet is a simple eye, it produces an inverted image; those images are combined in the brain to form one unified image. Because the aperture of an eyelet is larger than the facets of a compound eye, this arrangement allows vision under low light levels.<ref name=Land1992/>

Good fliers such as flies or honey bees, or prey-catching insects such as [[praying mantis]] or [[dragonfly|dragonflies]], have specialised zones of [[ommatidium|ommatidia]] organised into a [[Fovea centralis|fovea]] area which gives acute vision. In the acute zone, the eyes are flattened and the facets larger. The flattening allows more ommatidia to receive light from a spot and therefore higher resolution. The black spot that can be seen on the compound eyes of such insects, which always seems to look directly at the observer, is called a [[pseudopupil]]. This occurs because the [[ommatidia]] which one observes "head-on" (along their [[optical axis|optical axes]]) absorb the [[incident light]], while those to one side reflect it.<ref name="Zeil">{{cite journal |author1=Jochen Zeil |author2=Maha M. Al-Mutairi |year=1996 |title=Variations in the optical properties of the compound eyes of ''Uca lactea annulipes'' |journal=[[The Journal of Experimental Biology]] |volume=199 |issue=7 |pages=1569–1577 |doi=10.1242/jeb.199.7.1569 |url=http://jeb.biologists.org/cgi/reprint/199/7/1569.pdf |pmid=9319471 |access-date=2008-09-15 |archive-date=2009-02-25 |archive-url=https://web.archive.org/web/20090225084203/http://jeb.biologists.org/cgi/reprint/199/7/1569.pdf |url-status=live }}</ref>

There are some exceptions from the types mentioned above. Some insects have a so-called single lens compound eye, a transitional type which is something between a superposition type of the multi-lens compound eye and the single lens eye found in animals with simple eyes. Then there is the [[mysid]] shrimp, ''Dioptromysis paucispinosa''. The shrimp has an eye of the refracting superposition type, in the rear behind this in each eye there is a single large facet that is three times in diameter the others in the eye and behind this is an enlarged crystalline cone. This projects an upright image on a specialised retina. The resulting eye is a mixture of a simple eye within a compound eye.

Another version is a compound eye often referred to as "pseudofaceted", as seen in ''[[Scutigera]]''.<ref name="Müller 2003">{{cite journal|last1=Müller|first1=CHG|last2=Rosenberg|first2=J|last3=Richter|first3=S|last4=Meyer-Rochow|first4=VB|title=The compound eye of Scutigera coleoptrata (Linnaeus, 1758) (Chilopoda; Notostigmophora): an ultrastructural re-investigation that adds support to the Mandibulata concept|journal=Zoomorphology|date=2003|volume=122|issue=4|pages=191–209|doi=10.1007/s00435-003-0085-0|s2cid=6466405}}</ref> This type of eye consists of a cluster of numerous [[ommatidia]] on each side of the head, organised in a way that resembles a true compound eye.

The body of ''[[Ophiocoma wendtii]]'', a type of [[brittle star]], is covered with ommatidia, turning its whole skin into a compound eye. The same is true of many [[chiton]]s. The tube feet of sea urchins contain photoreceptor proteins, which together act as a compound eye; they lack screening pigments, but can detect the directionality of light by the shadow cast by its opaque body.<ref name="Ullrich-Luter2011">{{Cite journal | last1=Ullrich-Luter | first1=E.M. | last2=Dupont | first2=S. | last3=Arboleda | first3=E. | last4=Hausen | first4=H. | last5=Arnone | first5=M.I. | title=Unique system of photoreceptors in sea urchin tube feet | doi=10.1073/pnas.1018495108 | journal=Proceedings of the National Academy of Sciences | volume=108 | issue=20 | pages=8367–8372 | year=2011 | pmid= 21536888| pmc=3100952| bibcode=2011PNAS..108.8367U | doi-access=free }}</ref>