Hyperopia (farsightedness)

A condition of the eye in which only distant objects produce images slightly more distinct then near ones because parallel rays of light reach the retina before they are focused.

 

Astigmatism
The structural defect of an eye or of a lens that makes objects look indistinct or gives imperfect images. With perfect focus, all the rays of light entering through the cornea, converge at one point on the retina; with astigmatism they do not. Astigmatism is frequently combined with other vision problems such as myopia and hyperopia.

 

Presbyopia
A condition of the eye cornea occurring in middle and old age, in which only distant objects may be seen distinctly. When the lens of the eye becomes less elastic and loses some of its ability to focus on objects close to the eyes.