Monovision
Monovision is an attempt to minimise dependence on glasses following refractive surgery or cataract surgery.
It is only required in middle aged and older patients.
In monovision, one eye, the dominant eye, is adjusted so that it is clear and focused in the distance. The other eye is left adjusted for near.
Thus between the two it is possible to see well at distance and at near.
It is however a compromise as you are only really using one eye at any given time. Surprisingly most people adapt well to this situation and are not usually conscious of using one eye at at time