I've said it about a thousand times, but there is a contact lens out there for everybody. When people hit the age of 40, the eyes start doing all kinds of weird things and that is around the time patients start noticing the need for bifocals and rush to their eye doctor to get it corrected. For contact lens wearers, that shift in the need for a more specialized correction meant they had to go back to glasses. Now, there are many options available that incorporate different prescription powers so that those in need of multifocal contacts have options.
How do these multifocal contact lenses work? Most people are familiar with glasses and the no-line transitions but how multifocal contacts work is slightly different. Kinda.
There are actually a few ways that multifocal contacts correct for mutliple distances. One common method used by contact lens makers is to put concentric circles in the lens that correct for different distances. The following crudely drawn diagram I found through an image search actually does a good job at showing what I am talking about
This is just one way of correcting for multiple points of focus. There are also a few other ways to correct with multifocal contact lenses that are closer in proximity to how no-line progressive lenses glasses work, just on a much smaller scale.
Now the question becomes, how does the contact move to the right area of correction. The trick is that the the eye is the one that "moves" to focus on the right part of the contact. It is such a slight focus adjustment that people will not be able to tell the eyes have "moved." That, in a nut shell, is how multifocal contacts work. Remember, your optometrist will have more information when you go in for your next contact lens fitting if you are really looking to get the fine details on how the mutlifocal contacts work.