Bifocal lenses are lenses that have only two lens powers. One power for seeing distant objects clearly (located at the top) and a second power in the
lower section of the lens (referred to as the segment) , for near vision. There is a visible “bifocal line” that is seen where these two different powers meet.
Progressive lenses, on the other hand, look the same as single vision lenses. Progressive lenses provide a seamless progression from distance to intermediate to near vision They help you see clearly at all distances, without the “bifocal line” that’s visible with Bifocal lenses.
We know what you’re thinking! You want to choose Progressive lenses over Bifocals to prevent those “bifocal lines?” Well, Progressive and Bifocal lenses are intended for different purposes and each possess their own benefits and drawbacks.
Firstly there is no “perfect lens” as each lens type has its own benefits and differences depending on your visual requirements.
Bifocal lenses are relatively simply compared to progressive lenses. They offer very wide and comfortable distance and reading zones but they lack an “intermediate zone” which is what is needed for computer use and any task that requires you to be at around an arms length distance. Bifocal lenses also have the “bifocal line” that some view as a cosmetic disadvantage.
Progressive lenses on the other hand do have an intermediate zone that allows for clear vision on computers and any task at any distance as well as the advantage of no “bifocal line” BUT the distance and reading zones, when compared to bifocal lenses, are smaller. The progressive lens design also dictates that you must use more head movements to ensure that your eye always stays within the center region of the lenses and not the periphery in order to maintain clear vision.
As you can see, both Progressive and Bifocals have great benefits but they also have differences based on your particular visual requirements. If you experience symptoms of Presbyopia, book your eye exam and your optometrist will recommend which prescription lens is best for you!