Sight defects - Myopia, Hyperopia, Astigmatism and Presbyopia

Sight Defects

Myopia

Short sightedness

If you are short sighted, you'll find that reading and close work is not usually a problem but that your distance vision is blurred.

This happens because the lens in your eye focuses the image in front of the retina (the light receptor at the back of the eye). Minus power lenses (lenses that are thinner at the centre and thicker at the edge) will correct the problem very easily. If you have a higher prescription, you will find special high index lenses will make your lenses thinner, lighter and flatter than conventional lenses.

alt : Myopia

alt : Hyperopia

Hyperopia

Long sightedness

If you are long sighted, you'll find that your distance vision is not usually a problem but focusing on close work is difficult and generally blurred. This often shows itself with headaches caused by your eyes struggling to focus close up.

This happens because the lens in your eye focuses the image behind the retina (the light receptor at the back of the eye). Plus power lenses (lenses that are thicker and at the centre and thinner at the edge) will correct the problem very easily. High index lenses will make your lenses thinner, lighter and flatter than conventional lenses.

Astigmatism

'Rugby Ball' shaped eyes

Astigmatism is usually caused by an irregularity in the shape of the eyeball (if shaped slightly like a rugby ball rather than a football) or the eyes own lens (the crystalline lens). People who suffer from this type of refractive error may screw up their eyes or be sensitive to light. 

A special toric lens corrects the problem.

alt : Astigmatism

Presbyopia

Aging eyes

Why does our eyesight naturally deteriorate as we age? Presbyopia is simply a gradual loss of flexibility in the lens inside the eye. When we are young the lens is exceptionally flexible, letting us change focus instantly without strain. As we grow older, it loses elasticity and we start to find it harder to focus.

Book an appointment to come and see us, and we can give you an eye examination and explain what's happening to your eyes, then advise you on the range of lenses and frames available to improve your vision.