SPLIT LENS FOR DISTANCE AND NEAR
Bifocal lenses give you the ability to see at distance and near. The lens is split into two different optical portions, the upper portion providing the ability to focus on distance objects such as watching TV, the lower part for close reading.
The split between the two different portions can be seen with a distinct line. This type of dual focus lens tends to be very simple to adapt to compared with varifocal lenses.