Long years ago, you have to wear two sets of eye glasses, then doctors discovered the lens at the bifocal eye-glasses ,then recently they do the same thing in a bifocal contact lens. The lens is divided into two halves ,one upper and the other is lower and sometimes it can be in concentric circles ,one lens on the interior part and the other is on the outside part.
Who need bifocal lenses?
People who suffer from Presbyopia that causes trouble focusing on objects which are near and this doesn’t develop after the age 40.They are nearsightedness and farsightedness and suffer from the eye-glasses that are usually with thick lenses and a line across them (they act as two lenses in one).These eye-glasses have several problems: First :They are heavy, Second: They are almost unattractive, Third: It is hard to adjust to them as you have to look up or look down .All these problems cause dizziness during adapting to these bifocal lenses .The only choice for these people for long years ago was the eye-glasses even after contact lenses came on the market.
Now ,contact lenses offer bifocal contact lenses which are soft ,rigid and with gas permeable materials .It is...