The eye – a marvel

Our most important sensory organ works like an ultra sensitive camera.

The eye is a complex optical system made up of the cornea, crystalline lens and vitreous body, which deflects or refracts incoming light. The total power of refraction from all these optical components is expressed in dioptres (dpt). In a normal-sighted eye the rays of light are refracted so that they land at the exact centre of the retina – at the point of best vision. Images are thus perceived in focus.

Defective vision

If the focal point does not fall exactly on the retina, but instead in front of or behind it, the object viewed is represented in a blurred manner: This is known as defective vision. Distinctions are made between near-sightedness, far-sightedness, astigmatism and age-induced far-sightedness.

Normal-sighted eye
Normal-sighted eye

Normal-sighted eye

The focal point of a normal-sighted eye is exactly on the retina for objects close up and at a distance. This is why close objects and distant objects are perceived clearly.

Methods and applications for corneal procedures

  Near-sightedness Far-sightedness Astigmatism Wavefront/ aberrometry
Femto-LASIK/LASIK up to -8 dpt up to +3 dpt up to 4 dpt possible
LASEK/PRK up to -6 dpt up to +1 dpt up to 3 dpt possible