Human eye anatomy

The retina (; or retinas) is the innermost, light-sensitive layer of tissue of the eye of most vertebrates and some molluscs. The optics of the eye create a focused two-dimensional image of the visual world on the retina, which then processes that image within the retina and sends nerve impulses along the optic nerve to the visual cortex to create visual perception. The retina serves a function which is in many ways analogous to that of the film or image sensor in a camera.

thumb|Blood vessels of the eyelids, front view

The cornea is the transparent front part of the eye which covers the iris, pupil, and anterior chamber. Along with the anterior chamber and lens, the cornea refracts light, accounting for approximately two-thirds of the eye's total optical power. In humans, the refractive power of the cornea is approximately 43 dioptres. The cornea can be reshaped by surgical procedures such as LASIK.

transparent structure in the eye

The sclera, also known as the white of the eye or, in older literature, as the tunica albuginea oculi, is the opaque, fibrous, protective outer layer of the eye containing mainly collagen and some crucial elastic fiber.

photo sensitive cells that detect color

cavity or socket of the skull in which the eye and its appendages are situated

photoreceptor cells that can function in lower light better than cone cells.

clear gel that fills the space between the lens and the retina of the eyeball

The choroid, also known as the choroidea or choroid coat, is a part of the uvea, the vascular layer of the eye. It contains connective tissues, and lies between the retina and the sclera. The human choroid is thickest at the far extreme rear of the eye (at 0.2 mm), while in the outlying areas it narrows to 0.1 mm. The choroid provides oxygen and nourishment to the outer layers of the retina. Along with the ciliary body and iris, the choroid forms the uveal tract.

thumb|Image of a human eye showing the blood vessels of the bulbar conjunctiva thumb|Hyperaemia of the superficial bulbar conjunctiva blood vessels

The macula (), in full macula lutea, is an oval-shaped pigmented area in the center of the retina of the human eye and in other animals. The macula in humans has a diameter of around and is subdivided into the umbo, foveola, foveal avascular zone, fovea, parafovea, and perifovea areas.

specialized type of cell found in the retina that is capable of visual phototransduction

fold on upper eye lid

transparent, watery, fluid similar to plasma, but containing low protein concentrations, secreted from the ciliary epithelium

paired, almond-shaped exocrine gland, one for each eye, that secretes the aqueous layer of the tear film

part of an eye

The uvea (; derived from meaning "grape"), also called the uveal layer, uveal coat, uveal tract, vascular tunic or vascular layer, is the pigmented middle layer of the three concentric layers that make up an eye, precisely between the inner retina and the outer fibrous layer composed of the sclera and cornea.

eye muscle used for focusing

anatomical structure

space in the eye between the cornea and lens which contains the aqueous humor

lymphatic-like vessel in the eye

set of exocrine glands, along the rims of the eyelid

type of neuron located near the inner surface (ganglion cell layer) of the retina of the eye

physiological system containing the orbital structures for tear production and drainage

seven extrinsic muscles of the human eye

carries tears from the lacrimal sac of the eye into the nasal cavity

part of the eye

part of the eye

extraocular muscle that elevates the eye

Muscle in orbit that elevates upper eyelid

part of the eye

extraocular muscle that rotates the eye medially

Layer of cells in the eye

upper, dilated end of the nasolacrimal duct

muscle in the orbit

cell type

part of the eye

muscle on lateral side of the eye

region of the eyeball between the iris and lens

the border of the cornea and the sclera

layer of the cornea, basal lamina of the corneal endothelium

concave interior of the eye

layer in the cornea of the eye

layer of the human cornea

area of tissue in the eye

type of neuron

small channels in each eyelid that drain lacrimal fluid

thumb|Crystal structure of Duck Delta 1 Crystallin, based on the Protein Data Bank|PDB file 1HY0. In anatomy, a crystallin is a water-soluble structural protein found in the lens and the cornea of the eye accounting for the transparency of the structure. It has also been identified in other places such as the heart, and in aggressive breast cancer tumors. The physical origins of eye lens transparency and its relationship to cataract are an active area of research. Since it has been shown that lens injury may promote nerve regeneration, crystallin has been an area of neural research. So far, it

front third of the eye

a single layer of cells on the inner surface of the cornea

connective tissue in the eyelid

cell type

muscle arise from annular tendon is medial rectus,superior rectus,inferior rectus and lateral rectus

part of a human eye

neuron in the retina of the mammalian eye

membrane in the eye

where rod and cone terminate

folded layers in the anterior of the eye

small, reddish-yellowish, globular nodule at the inner corner (the medial angle) of the eye