These lenses have just one focus, and are the simplest way to compensate for long sightedness, short sightedness or astigmatism. They can also be used for reading glasses. When you are under 40, the eyes natural ability to change focus means that, for most people, single vision lenses are all you need.
Bifocals simply means two focuses, so if you need a different optical prescription for reading than for driving, both prescriptions are available in the one lens. This becomes a common problem from the mid-forties on.
What if you don’t want a line on your glasses? What if you want to see at more than 2 focuses? Then Multifocals, sometimes called progressive addition lenses may be for you. There are no lines on these lenses, and the power gradually increases towards the bottom of the lens.
Anti-glare coatings enable transparent, clear and unimpaired vision which makes glasses more attractive and permits uninterrupted and reflection-free vision for the wearer.
In offices and production facilities your eyes normally have to cope with bright lighting. The first sign of presbyopia initially require lenses fo reading only, but none for distance vision. The solution may may be computer lenses that are precisely optimised for the distances you need so you can walk around the office or talk to customers without any problems while waring your computer glasses.
For glasses to work, they need lenses to alter the path of light entering the eye. Lenses work by putting an image of what you are looking at at an apparent distance from your eye that matches the eyes natural focus. Sometimes, this can actually be behind your head!