Single vision lenses have the same power across the whole lens and are usually used for distance or reading.
Lenses may be enhanced by adding anti reflex coatings, tinting or transitiontinting.In the case of higher prescriptions high index or aspheric lenses may be a benefit.
Bifocal lenses have two portions to the lens with a dividing line.Each area is used for reading or distance vision.
Just like a bifocal progressive lenses allow one to see at both distance and when reading but without a dividing line. Progressive lenses allow one to focus at multiple distances which is ideal for office and computer work. Modern progressive lenses have reduced distortion and can be fitted into smaller frames. Some progressive lenses are specifically designed for different tasks and the optometrist will be able to advise which are the best depending on ones specific needs.
These lenses darken in the sun and lighten when indoors. New technology means they offer 100% UV protection as well as being almost totally clear indoors or at night.
Anti reflection coatings reduce reflections off the lens surface which in allowing more light through the lens improves your vision as well as making your spectacles look more attractive. Hoya’s Diamond finish anti reflection coating has the added advantage that it is as scratch resistant as some types of glass.
Anti reflection coating is a new coating which reduces transmission of harmful blue light. Blue light has been implicated in the development of macula degeneration as well as fatigue associated with computer screen work.
Thinner and lighter lenses higher density lens materials can be used to reduce the weight and thickness of lenses. At Birkenhead optometrists we have a computerised system which can show you the advantages in 3D of these thinner lenses.