Approximate spherical eyes, is located within the orbit. Normal adult of its average diameter 24mm, down an average diameter of 23mm. The most prominent in orbit outside the front of 12 - 14mm, by eyelid protection. Including the eye wall of the eyeball, eye cavity and contents, nerves, blood vessels and other organizations.
1. Eyeball wall divided into outer, middle and inside the three-tier.
Outer layer from the cornea, sclera composition. The former 1 / 6 for the transparent cornea, and the remaining 5 / 6 for the white sclera, commonly known as "white." The outer eye to maintain eye shape and eye protection organizations. Cornea is to accept the entrance of the information the most outposts. Cornea is a transparent eyeball anterior part of the light into the eye after this. Cornea is slightly oval-shaped, slightly forward process. Diameter for the 11.5-12mm, vertical diameter of about 10.5-11mm. Thick around 1mm, the central government as 0.6mm. Pre-corneal tear film layer of the cornea to prevent drying, and maintain smooth and optical characteristics of the cornea role. Cornea is rich in nerves, astute. So the cornea is not only light to enter the eye and refracted image of the main structure, but also to protect the role and determination of the human body is an important part of perception. Sclera for dense collagen fiber structure, opaque, showing white, resilient texture.
Middle, also known as uveal, pigment membrane, is rich in pigment and blood vessels, including the iris, ciliary body and choroidal three parts.
Iris: ring was round, the most in uveal the first part, located in Crystal ago, said fold radial texture, with uneven surface recess. People of different races in different colors of the iris. Central has a 2.5-4mm of the hole, said the pupil. Ciliary body before then iris root, followed by choroidal, lateral to the sclera, the medial suspensory ligament through the Department of the equator and Crystal connected. Choroidal located between the sclera and retina. Choroidal blood circulation nutrition outer retina, which contains a wealth of pigment from the role of shading darkroom.
Inner retina is a layer of transparent film, is also a form of visual nerves the first leg of the transmission of information. Has a very sophisticated network architecture and extensive metabolic and physiological functions. Retina is to finish as the axis for macular foveal. Macula is the retina most sensitive visual special region, a diameter of about 1-3mm, the central government as a small concave, or foveal. Macular nasal Department about 3mm a diameter of 1.5mm red light district, for the optic disc, also known as the optic nerve is pooled retina visual fiber transmission backbone to the visual parts of the eye, no photoreceptor cells, it appeared for the vision inherent in the dark zone, saying that the physiological blind spot.
