Sunlight can increase the long-term risk of developing conditions such as cataracts.
Good sunglasses don’t need to be expensive: you can purchase perfectly adequate protective sunglasses from high street stores. Look out for glasses carrying the “CE” Mark and British Standard BS EN ISO 12312-1:2013, which ensures that the sunglasses offer a safe level of UV protection, and get reasonably dark glasses: for example, dark brown offers more protection than light grey.
It’s even more important to protect children’s eyes as they are still developing.
Whatever your prescription, it is important to protect the eyes against excessive ultraviolet (UV) radiation. Protection is needed to avoid reflected light from sand and snow or if you spend long periods out of doors, particularly in the summer. Prescription sunglasses can be made with single-vision, bifocal or varifocal designs to offer the same standard of protection as non-prescription sunglasses.
Safety and sports glasses
Special lenses and frames incorporating eye protection are available for a variety of safety and recreational uses.
Photochromic lenses are lenses that change colour according to light conditions. When exposed to sunlight they darken quickly to eliminate glare and to protect the eyes against UV. These lenses are generally nearly clear when it is dark.
Many people wear these lenses and find them convenient as they can avoid the need to carry prescription sunglasses. Modern photochromic materials react and fade quickly, suit most prescriptions and are more likely to be lightweight plastic than glass.
Points to consider concerning tinted and/or photochromic lenses
Those considering using photochromic lenses and/or tinted lenses need to consider their usage, particularly for activities in low light conditions where vision is critical, such as driving at night.
Several factors should be considered:
- Any tint will reduce the amount of light that is entering your eye. The darker the tint the more the light will be reduced. You should not wear a dark tint for night driving.
- We generally see better in the light than in the dark so the more light that enters your eye the better (providing it is not dazzling you).
- As some light is lost from reflection from the lens surfaces, the performance of all lenses is enhanced if they are coated with an anti-reflection coating to reduce the reflections from the front and back surfaces of the lens. This is particularly important for the thinner, high index lenses. Your optometrist or dispensing optician will be able to advise you on this.
- The amount of light transmitted by modern photochromic lenses in their clear state with a multi anti-reflection coating, is not much less than that transmitted by a clear, non photochromic lens without an anti-reflection coating.
- Some of the older photochromic materials do not go as clear as the newer ones. We recommend that you choose the best lens that you can afford, particularly if you wish to use the lenses for critical vision at night.
- The performance of some of the older photochromic materials degrades over time. If you notice that your photochromic lenses do not go as clear as they used to you should buy a new pair.
- Older people need more light entering their eyes than younger people because the eye naturally absorbs more light as it ages.
- When driving you may find your photochromic lenses do not become as dark as they do outside. Car windscreens (and windows) filter and absorb most of the short wavelength light (near UV) that would normally trigger the darkening process.
For further advice, contact your optometrist or dispensing optician who will be able to advise you on which particular lens is most suitable for you.
You might also like to see our page on summer eye care.