Are there advantages or disadvantages to progressive lenses?
As we get into our forties and start losing our reading vision, people get what we call multifocal lenses or progressive lenses. That's a lens with one prescription on the top for distance and a different prescription down below for reading. Now, normally bifocals have a line across separating those two zones, but you can get progressive lenses where that line is blurred out. People like that because that line is a sign of age. It's like putting a sign around your neck that says "Grampa", or "Grandma", and a lot of people don't like that. So progressive lenses cosmetically are very nice. They also have the advantage in that between the top and the bottom is an intermediate zone that's very good for computer. The disadvantage of progressive lenses is that the field of vision is not as wide, and so if I'm looking at you, the vision's clear straight ahead but off to the side, it's not quite as clear so I have to turn my head. And that's just a little bit inconvenient, you have to take some getting used to. But most people adapt to that, so the choice of bifocals versus progressives depends on cosmetics and on your comfort adapting your head movements to a limited field of view.
