Lens Surgery

The eye is a complex optical device with an incredible impact on our life. Most people will need spectacles or contact lenses at some point during life for a variety of reasons including nearsightedness (‘myopia’), farsightedness (‘hypermetropia’), astigmatism, and reading disability (‘presbyopia’). In all of these situations the lens plays a central role.

Ray tracing human eye

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The normal eye
The normal eye can see without spectacles because light from a distant object is focused on the retina by the cornea and the lens.

Nearsighted eye ('myopic eye')
The nearsighted eye is too long for the refraction in the cornea and the lens. The distant focus is in front of the retina and the vision is blurred.

Farsighted eye ('hyperopic eye')
The farsighted eye is too short for the refraction of light in the cornea and the lens. The distant focus is behind the retina and the vision is blurred.

Presbyopia (reading disability)
A young person can see without spectacles at near because the crystalline lens of the eye can increase its focusing power by a process called accommodation. The ability to accommodate is very high in childhood and decreases drastically during life.