The natural lens in a young person is flexible and can change focus smoothly between distance and near. There is no lens implant available today that is able to emulate this – all have a fixed point of focus that does not change.
The best quality of vision following cataract surgery is achieved by selecting a single focus lens implant to target good distance vision without glasses for both eyes and to wear glasses to focus for near. Most people choose this arrangement.
There are various new and established approaches to producing good vision for both distance and near in order to reduce dependence upon glasses. These include new lens implant designs and ways of combining them. Although potentially liberating for many people, all involve some compromise of quality of vision and so, they are not suitable for everybody. The arrangement involving least compromise is known as monovision – choosing a single focus lens implant to set the dominant eye for the distance and the fellow eye for intermediate vision. The same arrangement is quite often used by contact lens wearers who might otherwise need reading glasses.