Video and lesson investigations on the topic of eyes. Key concepts include:
- Eyes do not always work as well as they should. Eye tests can reveal eye problems.
- Artificial lenses can improve eyesight.
- Different strengths of lenses have different effects. Some lenses make objects seem larger.
- Others make objects seem smaller.
- Spectacles and contact lenses compensate for the defects in the natural lens of an eye by correcting or altering the path of the light before it gets into the eye.
- People with less than perfect eyesight are usually either ‘longsighted’ (where the light rays focus behind the retina making nearby objects seem fuzzy but faraway objects clear), or ‘shortsighted’ (where the light rays focus in front of the retina making nearby objects clear but distant objects fuzzy).