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Retinal pigment epithelium: This layer lying betwen the retina and choroid, contains melanocytes that make for its characteristic black color. This pigment allows the inside of the eye to absorb stray rays of light like the black paint inside a camera or within a dark room.he eyes are housed in protective bony structures of the skull called the orbits. Each eye is composed of a tough outer layer, the sclera and cornea; a middle layer, the choroid, ciliary body and iris; and the inner layer of nerve tissue called the retina.
Find an ophthalmologist near you Â». The cornea is a layer of clear tissue at the front of the eye that helps focus light. Located at the corner of each eye, tear ducts drain tears secreted by the lacrimal gland to the surface of the eye. Tears keep the cornea lubricated and clear of debris. The colored part of the eye is the iris. It is a muscle that controls the pupil, the opening in the middle of the eye that controls the amount of light coming in. The lens is behind the pupil and focuses light onto the retina, the light-sensitive cells on the back of the eyeball. Acting much like the film in a camera, the retina converts images into electrical signals that are sent to the optic nerve.