Distinguished from Bifocal contact lenses, multifocal contact lenses work in several different ways, that depends on the design of the lens. The designs can be divided into two basic groups.First,Translating lenses,Why they are called translating lenses is for the reason: your pupil alternates between the two powers, as your gaze shifts up and dowm. Simultaneous vision lenses require your eye to be looking through both distance and near powers at the same time. Although this might sound unworkable, your visual system learns to select the correct power choice makes differences according the distance you want to see.