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Best and worst opticians stores

Five steps to the right prescription glasses

By Joanna Pearl

Article 4 of 7

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Five steps to the right prescription glasses

Buying glasses with the right elements will give you the best vision and save money. Follow our essential, but simple, tips to do this effectively.

Our research shows that shoppers sometimes struggle to understand whether different glasses choices – such as lens coatings – are right for them, when buying a new pair of glasses.

Use our expert optician’s advice and five-step guide below to choose a pair of glasses that are the best price and fit for your eyes.

We also reveal the best- and worst-rated opticians brands.

1. Know the key different types of lens

Single-vision lenses have one prescription throughout the lens.

Reading glasses tailor single-vision glasses to your reading distance.

Enhanced reading glasses work at two reading distances – eg your book (close up) and computer (further away).

Varifocal lenses combine far-distance, intermediate, and close-up vision, if you don’t want multiple pairs. There's no visible line in the lens, as there is in bifocal lenses.

2. Understand lens materials and thicknesses

If you're looking for slim lenses, you're likely to encounter the term 'high index'. High index just means that the lens is thinner.

If you’re long sighted (over +2.00 prescription), consider a lens made 'minimum edge surfaced' (thinned). For a prescription over +3.00, consider a 1.67 high-index (thinner) lens, and for over +5.00, choose a 1.74 lens.

If you’re short sighted (over -2.00 prescription), consider Trivex  – a light but tough material – or high-index 1.6 lenses. For a prescription of over -4.00, select 1.67 lenses, and over -6.00, 1.74 lenses.

Smaller, round and oval frames give naturally thinner lenses, and can therefore help you avoid paying more for higher-index lenses.

If you're choosing rimless or half-frames. consider Trivex or 1.6 lenses for strength.

3. Get the right coatings for prescription glasses

Most lenses include scratch-resistance as a standard coating, and – in the case of some high-index (1.6+) or premium lenses – also an anti-reflective coating.

Choose an anti-smudge (oleophobic) coating if your anti-reflection coating accentuates annoying smears.

A UV coating protects to UV400 (sunglasses level) without changing the lens colour. Many lens materials inherently filter UV (such as Trivex, higher index and polycarbonate).  

Premium 'multi-coats' combine the benefits of lots of different coatings in one, typically anti-scratch, UV, anti-reflective, oleophobic and hydrophobic (water resistant) coatings.

There's little evidence most people would benefit from the priciest varifocals.

Joanna Pearl,
Principal Health Researcher

4. Don't pay over the odds for varifocals

There’s little evidence that most people would see more clearly or comfortably with the priciest varifocals, so many people can avoid trading up. See our advice on choosing varifocals for more on this.

The fitting measurements are crucial to how well your varifocals perform, so do ask your optometrist or dispensing optician to check the fitting.

5.Save money with suitable frames

If you have a moderate or high prescription, choosing your frames carefully could save you pounds in unnecessary upgrades. For example, a very large frame may well require a thinner (more expensive) index lens than a more suitable size and shape.

As a rule of thumb, your pupil distance should also be as close as possible as the frame size. This will reduce lens edge thickness.

Be cautious about selecting a rimless frame over +5.00, as the edge may be prone to cracking.

A dispensing optician, optometrist or experienced optical assistant will be able to advise you of how to choose the best shape of frame for your prescription, and ensure that the lenses are the best match.

If you want new lenses in existing frames, optical practices will always warn you that this is at your own risk - if they will do it at all - as an ageing frame loses some of its strength. This could mean that the frame breaks, and the lenses - which have been cut to fit - become redundant.

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