How To Choose Adaptive or Photochromic Lenses
Wearing prescription glasses and sunglasses in the summer can be a pain, always having to carry both pairs and changing between the two as you move from indoors to outdoors. However, thanks to light-adaptive photochromic lenses, it’s possible to wear just one pair all the time. These two-in-one glasses cleverly change with the lighting, protecting your eyes whilst saving you the inconvenience of always having to change glasses.
What Are Photochromic Lenses?
Photochromic Lenses look like regular clear lenses when indoors but automatically darken when moving into a brighter area. Ultraviolet (UV) rays from the sun affect the molecules in the photochromic lenses so they change colour. They will darken in the light even on overcast days as UV rays still penetrate clouds.
This provides you with the best possible vision in all lighting through different shades of tint, without you even needing to think about it. As Transitions™ is the most well-known brand of photochromic lenses, these types of glasses are often referred to as ‘transition lenses’. They’re also sometimes called adaptive lenses, auto-tinted lenses or variable-tint lenses. Photochromic glasses are not to be confused with polarised glasses (sunglasses). These have a set tint that protects from glare but they aren’t changeable; they don’t adapt to light in the same way photochromic lenses do.
What Are The Benefits Of Photochromic Lenses?
- They help reduce eye strain, eye damage and potential heightened risk of cataracts later in life by blocking up to 100% of UVA/UVB light.
- Convenience - there’s no need to carry both glasses and sunglasses, swapping between the two
- It may save you money - although photochromic glasses can be more expensive than ordinary prescription glasses, they’re effectively two-in-one, meaning you won’t have to buy separate glasses and sunglasses
How Do They Work?
Regular sunglasses block out particular wavelengths of light with either coloured filters or polarisation. As photochromic lenses are carbon-based, the molecules react to UV; they change shape and absorb the light, meaning the lenses start to look darker. The more UV rays there are, the darker the lenses will become. They adapt accordingly from clear through to different darker shades, depending on the levels of UV. The darkening can take up to 30 seconds for the tint to take effect on the glasses, and it can take between two to five minutes to return to normal when going back indoors.
They protect from UV rays, which helps your general eye health. Made from either plastic, glass or polycarbonate, photochromic lenses are available as different prescription glasses for people who have eyesight difficulties. Plastic photochromic lenses are often favoured over glass due to their molecular make-up; users often find the tint on plastic lenses to be more evenly distributed than on photochromic glass lenses.
Who Needs Them?
Photochromic lenses can be worn all day every day, just like normal glasses. Anybody can benefit from them, but especially those who regularly interchange from indoors to outdoors.
Photochromic glasses can be particularly good for children who are unlikely to be able to juggle two separate pairs of glasses - regular and sunglasses. It also helps their eye health from an early age by protecting eyes from the sun and UV rays.
Photochromic Vs Sunglasses: Everything You Need To Know
- Photochromic lenses adapt automatically to light, whilst sunglasses remain at the same level of tint, meaning sunglasses may not always be providing the best level of vision (e.g. they may be too dark in some situations)
- Photochromic glasses are convenient and time-saving, and can also save you money
- Some polarised sunglasses just tint the light making it easier on the eye
- Both sunglasses and photochromic glasses like Transitions™ Xtractive® help keep the sun from your eyes when driving
- The adaptive nature of photochromic glasses means they’re better for your eyes as it reduces squinting and eye fatigue, but for people who spend long periods in harsh sunlight, some quality sunglasses may be preferable
For more information or advice about photochromic lenses visit an optometrist near you.
Ready to try photochromic lenses?
Find your nearest optometrist and ask about Transitions™ lenses.