When you visit an optician or online optician there are choices available to add coatings onto your spectacle lenses. The purpose of these coatings is to enhance the longevity of your lenses, and/or improve your vision while wearing your lenses. Here we take a close look at coatings, and explain the advantages to you.
Anti-Scratch Coatings
These are also called hard coatings. They are available on their own or as a part of multi-coatings. Nowadays the vast percentage of lenses sold are made of plastic, which are safe, light and comfortable, but scratch more easily than traditional glass lenses. A hard layer will protect the lenses, and increase their lifespan.
If your lenses are thin plastic – also called hi-index or high density lenses – they will be softer than standard plastic, so make sure you order a coating on the lenses. It will make them last longer and give you clearer vision.
The anti-scratch layer makes the lenses resistant to every day, surface wear and tear scratches. You should still make sure that you never put the lenses face down on a surface, and wash plenty of fluid across them before wiping them with a cloth.
Anti-Reflection Coatings
These coatings actually make your vision sharper and clearer by eliminating the glare and interference caused by reflections in the lens surface. While they improve vision for all spectacle wearers, they are particularly useful if you use a computer and for driving at night. They allow all light through to the eye, unlike an uncoated lens where some light is reflected back.
If you are myopic (short-sighted) and your lenses have thick edges, you will see white rings around the lens edge – hence the phrase bottle-bottom lenses – the coating will help to reduce this effect. Even for lower prescriptions the appearance of the lenses is still improved, allowing people to see your eyes, not their reflection in your lenses.
As with hard coated lenses above, thin material lenses will benefit from this coating too. The best quality thin lenses have a coating which is tailor made to match the lens material. To protect the coating an added hard coat will go on top of it, so it is unusual to find anti-reflection coated lenses without an added hard layer.
Although the coating is not a tint, it will cut glare and be more comfortable in bright light. You can identify a coated lens as it will have an oil-on-water type colour on the back surface of the lens.
Clean Coatings
Lenses are often offered with a 3 in 1 coating, incorporating hard, anti-reflection and clean coatings. The clean coat stops dirt from sticking to the lens. Again, this coating improves both your vision and the performance of the lenses. It does not add visible colour, but you can tell it’s there if you run water across the lens, as it will bead and bounce off as the lens repels it.
These three coatings when used together will make your spectacle lenses last longer, give you the best possible vision, and make you look your best in your glasses.