Routine eye examination and visual assessment


When the parallel rays of light remain unfocused upon the retina, the eye is known as an ammetropic eye. This kind of an eye has refractive error. Refractive errors are the most commonly found type of vision defects.
Refractive errors are of three types: myopia, hypermetropia and astigmatism.
A defect of the eye that causes light to focus in front of the retina instead of directly on it, resulting in an inability to see distant objects clearly. Myopia is often caused by an elongated eyeball or a misshapen lens. Also called nearsightedness.
A defect of the eye that causes light to focus behind the retina instead of directly on it, resulting in an inability to see near objects clearly. Hyperopia is often caused by a shortened eyeball or a misshapen lens. Also called farsightedness.
visual defect in which the unequal curvature of one or more refractive surfaces of the eye, usually the cornea, prevents light rays from focusing clearly at one point on the retina, resulting in blurred vision.
After age of 40 the crystalline lens reduces ability to focus on near objects caused by loss of its elasticity. This is presbyopia, we will need glasses to read.