Single vision lenses, or Single focus lenses, have one focus point. Younger Patients generally will only require single vision lenses as they have enough Accommodation to move the focal point to where required.
Sometimes for our older patients, they will require a prescription with at least two focal points, in this case they will require different sets of Single focus lenses for different focal tasks.
Single Vision lenses are available in all lens materials, coatings and indexes.
Varifocals, or, progressive lenses have an infinite amount of focal points from Distance to Near Vision due to a ‘proggresive’ change in the curvature of the lens. Again, generally set for Distance through to Near Vision, these lenses can provide the user with any focal point they require.
The quality of the Varifocal is hugely important in how well the patient will get on with the lenses. There are many many Budget lenses on the market today and for some patients have tried these, not got on with them and therefore given up on Varifocals. At Scartho Eyecare, we have carefully selected a range of lenses we feel give the best value for money from budget to the premium end of the market.
Single Vision have one focal point, Bi-focals have two focal points. Generally set for Distance and Reading, but within reason, can be set for any specific task and focal lengths. Bi-focals have a definite line dividing the two focal points and the reading area comes in different shapes and sizes.
Bi-focals although perfect for some patients are not the modern solution for Presbyopia (needing an extra prescription for reading) so although they are available in different materials, indexes and coatings not all options are produced.
Hard Coat – applied to a plastic resin lens to improve the durability
HMAR – (Hard Multi Anti Reflective) Used to reduce light reflecting off the lens surface. They range in quality and specific uses
HMAR + Blue – Anti-Reflective coating with an extra element specifically designed to reduce the blue light emitted from computer displays, tablets and mobile phones
Hi-Index – A denser material used to produce thinner lenses
Photochromatic - A lens that goes darker in the sun. Many companies produce Photochromatic lenses, Transitions being the most popular. Also known as Reactolites and Reactions.
Polarized – A lens that reduces light reflected in one particular meridian – generally horizontal. Perfect for Driving, water Sports, Fishing etc.
Tint – Reduces the amount of light transmitted through the lens
UV Coat – Reduces harmful UV from being transmitted through the lens. Many HMAR coatings now come with a UV coat & all Zeiss lenses now offer full UV protection. Transition lenses all come with UV protection automatically.