The University of Tübingen's Institute of Anatomy has discovered a fish with a previously unknown type of eye. The aptly-named glasshead barreleye lives at depths of 800 to 1000 meters. It has a cylindrical eye pointing ...
Plants & Animals
Mar 20, 2014
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0
(PhysOrg.com) -- Scientists have a good overall understanding of human vision: when light enters our eyes, it is focused by the lens and strikes the retina in the back of the eye. The light causes some of the millions of ...
A research team from the Centre for Organismal Studies (COS) of Heidelberg University has demonstrated that complex retinal tissue can be cultured in a Petri dish from embryonic stem cells of bony fish. Until now, stem cells ...
Cell & Microbiology
Sep 3, 2021
0
196
The streaming of real-time information across your field of vision is a step closer to reality with the development of a prototype contact lens that could potentially provide the wearer with hands-free information updates.
Engineering
Nov 21, 2011
13
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Physicists at Technische Universitat Munchen (TUM) are using the special properties of graphene to produce key elements of an artificial retina. With their research program the researchers were admitted to the heavily funded ...
Nanomaterials
Aug 7, 2014
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Scientists from The University of Manchester have found a way to trick the eye into thinking the world is brighter than it actually is.
Cell & Microbiology
Jan 28, 2019
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222
The Centre of Microsystems Technology (CMST), Imec's associated laboratory at Ghent University (Belgium), announced today it has developed an innovative spherical curved LCD display, which can be embedded in contact lenses. ...
Hi Tech & Innovation
Dec 5, 2012
2
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(Phys.org) —Light striking the retina in the back of the eye is the first major step in the vision process. But when the photoreceptors in the retina degenerate, as occurs in macular degeneration, the retina no longer responds ...
(PhysOrg.com) -- NEC and Brother are both developing wearable prototype devices that use Retinal Imaging Display (RID) technology to project images directly on the wearer's retina. NEC's gadget is designed to interpret foreign ...
Scientists report they have successfully developed and tested the world's first ultrathin artificial retina that could vastly improve on existing implantable visualization technology for the blind. The flexible device, based ...
Materials Science
Aug 20, 2018
0
389
The vertebrate retina is a light sensitive tissue lining the inner surface of the eye. The optics of the eye create an image of the visual world on the retina, which serves much the same function as the film in a camera. Light striking the retina initiates a cascade of chemical and electrical events that ultimately trigger nerve impulses. These are sent to various visual centers of the brain through the fibers of the optic nerve.
In vertebrate embryonic development, the retina and the optic nerve originate as outgrowths of the developing brain, so the retina is considered part of the central nervous system (CNS).. It is the only part of the CNS that can be imaged non-invasively in the living organism.
The retina is a complex, layered structure with several layers of neurons interconnected by synapses. The only neurons that are directly sensitive to light are the photoreceptor cells. These are mainly of two types: the rods and cones. Rods function mainly in dim light and provide black-and-white vision, while cones support daytime vision and the perception of colour. A third, much rarer type of photoreceptor, the photosensitive ganglion cell, is important for reflexive responses to bright daylight.
Neural signals from the rods and cones undergo complex processing by other neurons of the retina. The output takes the form of action potentials in retinal ganglion cells whose axons form the optic nerve. Several important features of visual perception can be traced to the retinal encoding and processing of light.
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