Many people are very surprised when they first learn about how monovision contact lenses work. They are designed to combat the problem of presbyopia, which is very common in people who are getting a little older. It is the difficulty that many people have seeing objects that are very close to the eye, and instead of reaching for a pair of reading glasses you might be able to simply eliminate the problem by wearing monovision contact lenses.
The simple explanation of how they work is that the lens in one eye is meant to correct vision problems that are further in the distance and the lens in the other eye is meant to correct the presbyopia issue. This will generally be done by putting the longer distance correction lens in the dominant eye of the individual and putting the one that corrects vision at shorter distances in the weaker eye. If you didn’t know that you have a dominant eye, simply make a circle with your thumb and forefinger and hold it at arm’s length. Look at a point in the distance through that circle and then alternatively close each eye. That will tell you which of your eyes is dominant.
It is an individual decision as to whether monovision contact lenses will be right for you. People will often find that the vision correction is not as good as it would be for regular contact lenses, so they may choose to simply pick up the reading glasses when it is time to see something that has to be held close to the eyes. If you talk to your eye care professional, they can clearly describe the effects of using monovision. They will also be able to tell you that it takes a little while to get used to it so you shouldn’t expect results right away.