How Transition Lenses Work
At GW Eye Associates, Drs. Gordon Wong and Wildon Wong provide comprehensive eye care for your vision and eye health needs along with the latest designer eyewear choices so you can look and see your best! To see our options for eyeglasses in La Jolla, CA, Carmel Valley, CA, or San Diego, CA, we welcome you to schedule a consultation.
If you’re considering new eyeglasses, you may be wondering about transition lenses. Transition lenses are both convenient and practical, making it possible to enjoy the benefits of eyeglasses and sunglasses in a single pair of frames. These special lenses shift from clear to tinted when exposed to sunlight, but what are they and how do they work?
What Are Transition Lenses?
Transition lenses, also called photochromic lenses, are lenses that darken when exposed to ultraviolet (UV) light. These lenses darken to the appropriate tint based on light conditions and transition back to clear when indoors and away from UV light.
Transition lenses begin to darken as soon as they’re exposed to the sun’s UV light. Once back indoors or shielded from UV light, transition lenses will begin to shift back to clear. Transition lenses generally fade back to clear within a few minutes. This makes it possible for eyeglasses to also act as sunglasses without needing to change frames.
How Do Transition Lenses Work?
We know that transition lenses darken when exposed to UV light but how do these lenses automatically transition back and forth between clear and dark?
In order to make lenses photochromic, a layer of light-sensitive molecules are applied. These molecules change their structure when exposed to UV light, causing the molecules (and subsequently the lenses) to darken.
The more UV light the molecules are exposed to, the darker they become and the faster they shift. Once UV light is removed, the molecules (and lenses) shift back to clear.
Can Transition Lenses Replace Prescription Sunglasses?
Transition lenses can help protect the eyes from harmful UV light from the sun and keep the eyes comfortable when exposed to bright sunlight. Transition lenses are convenient and allow eyeglass wearers to avoid switching back and forth between their eyeglasses and sunglasses when out and about.
They can be used in place of traditional prescription sunglasses for many activities, but some patients may still benefit from having a dedicated pair of prescription sunglasses, particularly for driving. This is because photochromic lenses don’t always darken sufficiently when driving because UV light is often blocked by a car’s windshield. Some people may find traditional prescription sunglasses work better for them when driving.
Another key difference to consider is polarization. Polarized lenses have filters that reduce glare, which helps prevent eye strain. Photochromic lenses are generally not polarized, making traditional polarized sunglasses best for people who want their eyewear to reduce glare.
Are Transition Lenses Right for You?
If you are interested in transition lenses and would like to learn more about your eye care options, we welcome you to schedule a consultation at GW Eye Associates.
