Retina diagram6/23/2023 It transfers all the visual information to the brain which then interprets them as images. The optic nerve is a thick bundle of nerve fibers that connect the back of the eye (retina) to the brain. When light hits the retina, a picture travels through the optic nerve to the brain. The retina is a thin layer of tissue that lines the inside of the back of the eye and is like the film in the back of a camera. Cornea: The front transparent part of the sclera is called the cornea. It consists of the following parts: Sclera: It is the outer covering, a protective tough white layer called the sclera (white part of the eye). The remaining larger area of the retina is responsible for our peripheral, or side, vision. A human eye is roughly 2.3 cm in diameter and is almost a spherical ball filled with some fluid. The detailed vision is known as our central vision. It is a very small area but has a high concentration of light sensitive cells (photoreceptors) that allow us to read and see in fine detail. This tiny area is responsible for sharp central vision essential for reading, driving, and any activity where visual detail is important. The fovea is located in the centre of the macula region of the retina. It is composed of layers of blood vessels that supply nutrients to inner parts of the eye. The choroid lies between the retina and sclera. Composed of over 99% water, it also contains collagen fibres and proteins. Lying between the lens and the retina, the vitreous is a clear jelly-like substance which occupies about two-thirds of the eye. It is tough tissue which serves as the eye's protective outer coat. Part of the sclera can be seen at the front of the eye. They are separated by two synapses from the photoreceptors, and the intervening wiring suggests. The sclera is the white covering that protects the eye, commonly known as ‘the white of the eye’. Retinal ganglion cells are the output neurons of the retina. It also contains the ciliary muscle, which changes the shape of the lens when the eye focuses, this movement is called 'accommodation'. The ciliary body lies just behind the iris and releases a transparent liquid called the aqueous humor within the eye. The cornea is shaped like a dome and bends light to help the eye focus. First, light passes through the cornea (the clear front layer of the eye). Injury, disease, or hereditary conditions can cause clouding, distortion, or scarring of the cornea, which may all interfere with vision. All the different parts of your eyes work together to help you see. The cornea is the clear window of the eye and helps focus the light onto the retina. The size of the pupil determines the amount of light that enters. A schematic section through the human eye with a schematic enlargement of the retina The retina is approximately 0.5 mm thick and lines the back of the eye. The pupil is the opening in the centre of the iris that regulates the amount of light entering the eye. The total retina is a circular disc of between 30 and 40 mm in diameter (Polyak, 1941 Van Buren, 1963 Kolb, 1991). The lens of the eye is located behind the pupil, its purpose is to focus light onto the retina. The colour, texture, and pattern of an iris are as unique as a fingerprint. The iris contains tiny muscles that widen and narrow the pupil size. Use the buttons below to learn more about. It controls light levels inside the eye, similar to the aperture on a camera. We will provide you with the answers and treatments if you have a retinal disease or damage. The iris is the coloured part of the eye which surrounds the pupil. the most distant from the centre of the eye, layer of the retina.Click the parts of the eye to see a description for each. ![]() The pigmentary layer (or "Tapetum Nigrum") is the most external - i.e. More about the membrana limitans externaĪre the more numerous to the two), and cones. In common with the membrana limitans interna, the membrana limitans externa is formed from the fibres of Müller. The inner nuclear layer contains sub-layers of oval-shaped components called rod-granules and cone-granules. The outer molecular layer is a dense network of tiny fibres extending from the processes of cells of inner nuclear layer. The inner nuclear layer consists of three different types of cells that are packed closely together. The inner molecular layer consists of a network of fibres connecting and meshing together the dendrites of ganglion cells with cells of the inner nuclear layer. The ganglionic layer is a single layer of large ganglion cells stretching across the retina except in the region of the fovea where there are several ganglia deep. The stratum opticum is the extension of the optic nerve and is at its thickest around the optic disc, gradually reducing in thickness towards the ora serrata. The membrana limitans interna is the retinal layer located nearest to the centre of the eyeball - in contact with the hyaloid membrane of the vitreous humour.
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