Optics and vision

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Vision of humans and other organisms depends on several organs such as the lens of the eye, and any vision correcting devices, which use optics to focus the image.

The eyes of many animals contains a lens that focuses the light of its surroundings onto the retina of the eye. This lens is essential to producing clear images within the eye.

However, some individuals may have problems with focus, such as myopia or presbyopia. In this case, the focus of the eyes can be corrected with an external lens, such as glasses or contact lenses, or through surgery.