GCSE Biology (AQA)
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Homeostasis and Response
The Human Nervous System
Correcting Eyesight
2:26
The Eye
Spec
4.5.2.3
- Various methods exist to correct common eyesight issues.
- Options include using hard or soft contact lenses, which function similarly to glasses by bending light to correct vision.
- Laser surgery can alter the shape of the cornea, the transparent front layer of the eye.
- Lens replacement surgery involves substituting the eye's natural lens with an artificial one.
- Traditional spectacles (glasses) help by refracting light to focus properly on the retina.
- Spectacle lenses correct myopia (shortsightedness) by bending light outwards, focusing it on the retina.
- They also correct hyperopia (longsightedness) by bending light inwards to focus on the retina.
- Myopia requires a concave lens, which has a caved-in shape.
- Hyperopia requires a convex lens, which refracts light inwards to focus images on the retina.
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