HOW DO THEY WORK?
Regular sunglasses block out particular wavelengths of light with either coloured filters or polarisation. As photochromatic 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, photochromatic 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 photochromatic glass lenses.
WHO NEEDS THEM?
photochromatic 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.
photochromatic glasses can be particularly good for children who are unlikely to be able to juggle two separate pairs of gasses – regular and sunglasses. It also helps their eye health from an early age by protecting them from the sun and UV rays.
PHOTOCHROMATIC VS SUNGLASSES: EVERYTHING YOU NEED TO KNOW
- Photochromatic 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)
- Photochromatic 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 photochromatic glasses like Transitions Xtractive help keep the sun from your eyes when driving
- The adaptive nature of photochromatic 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