The human eye is a complex structure. In order for us to see, light must pass through the clear cornea at the front of the eye and a lens behind the iris and pupil to reach the retina at the back of the eye. Much like a camera, light is refracted (bent) as it passes through these structures so that a sharply focused image is formed on the retina. Just like the effect of light falling on the light-sensitive chip of a digital camera, the image formed on the retina generates numerous electrical signals which are then processed in the retina and the brain to create the ‘picture’ we perceive and recognise as vision. When the refracted light rays are not focused to form a clear image on the retina, the eye is said to have a refractive error. The most common types of refractive error are Myopia, Hyperopia, Astigmatism and Presbyopia.
Eye Conditions
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Myopia
Read moreMyopia (short-sightedness or near-sighted) occurs when the focal point of light rays entering the eye forms an image in front of the retina, rather than directly on its surface. This results in a blurred or defocussed image falling on the retina. […]
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Hyperopia
Read moreHyperopia (long-sightedness or farsighted) occurs when the light rays entering the eye form an image behind the retina, rather than directly on its surface; resulting in blurred vision. Individuals with hyperopia will typically have difficulty seeing close objects (e.g. books, […]
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Astigmatism
Read moreAstigmatism occurs when the cornea does not have a spherical surface (like the surface of a basketball) but is steeper in one axis (like an AFL football). This results in light focusing irregularly rather than a sharp round point. As […]
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Presbyopia
Read morePresbyopia occurs with normal ageing as the focusing lens within the eye loses some of its flexibility and the eye can no longer focus as clearly on near objects. This condition usually becomes apparent between the ages of 40 and […]
