What Are Photochromic Lenses?

Photochromic lenses are lenses that function as normal glasses while indoors and darken upon going outside. While many people are familiar with the term “Transition Lens,” it’s important to note that this specifically refers to a brand of photochromic lenses made by EssilorLuxottica, and not all photochromic lenses fall under this brand.

What is a Photochromic Lens?

Photochromic lenses are eyeglass lenses that adjust their level of tint based on the amount of UV light they are exposed to. In the absence of UV light, such as indoors, the lenses remain clear like normal glasses. When exposed to sunlight, they darken, becoming sunglasses for comfort and protection from harmful UV rays.

How Do Photochromic Lenses Work?

The magic behind these lenses lies in their photochromic molecules. These molecules change structure when exposed to UV light, causing the lenses to darken by absorbing visible light. Once the UV light diminishes, the molecules return to their original state, and the lenses become clear again.

What Are The Benefits of Photochromic Lenses?

• Convenience: Having photochromic lenses eliminates the need for a separate pair of sunglasses, making it easier to move between indoors and outdoors by not having to switch between 2 pairs of glasses.

• Protection: Because of how photochromic lenses work, they block potentially harmful UV rays, keeping them from damaging your eyes. UV Rays can contribute to cataracts and other eye health issues over time.

• Comfort: Photochromic lenses reduce eye strain and provide overall comfort since your glasses will always be adjusted to the light around you.

• Individual Style: Photochromic lenses can be fit to most frames, allowing you to use your favorite independent frames as both glasses and sunglasses. 

What to Know Before Choosing Photochromic Lenses

While photochromic lenses offer several benefits, there are a few things to keep in mind. Photochromic lenses do need a little bit of time to adjust to changes in light conditions, so don’t expect them to be instant. Something else to know is that the speed and extent of color change in your lenses can be influenced by temperature, with colder conditions slowing down the process.

If photochromic lenses don’t sound right for you, there are plenty of other lens coatings, tings and treatments to consider for your next pair of glasses or sunglasses.

About The Author:

Will Benjamin is an advocate for independent eyewear and one of the driving forces behind Project Spex. With a passion for unique, collectible, and limited-edition eyewear, Will aims to inspire people to build their own collections through Project Spex, while supporting the success of independent opticals.