Eye defects are problems or malfunctions in a certain part of the eye. According to Hyperphysics, common vision defects include farsightedness, nearsightedness and astigmatism. Other eye defects include glaucoma, cataract, age-related macular degeneration, amblyopia, diabetic retinopathy, retinal detachment and dry eye syndrome.
Myopia (i.e. nearsightedness) is an eye condition wherein faraway objects appear blurry, while hyperopia (i.e. farsightedness) is an eye problem wherein nearby objects look blurry. In astigmatism, blurry vision results due to an imperfectly shaped cornea failing to direct light into the eye. Presbyopia is a type of farsightedness caused by a lack of elasticity of the eye’s lens brought on by aging. According to Healthline, these refractive errors are typically corrected through glasses, contact lens or surgery.
Another eye defect is a cataract, which is a clouding of the lens that prevents a person from seeing a clear, sharp image. The lens of the eyes is sealed in a capsule. Cataracts form as a result of old cells that get trapped in the capsule when they die. Over time, this leads to clouding over the lens.
Glaucoma is an eye condition caused by increased pressure of the fluid in the eye due to a malfunction in the eye’s drainage system. This damages the optic nerve and retinal fibers. When left untreated, it can lead to permanent loss of vision.