Lynn Valley Optometry
1233 Lynn Valley Rd #255 North Vancouver BC V7J 3H2 (604) 987-9191 $$$$

North Vancouver / 604.987.9191

Book Your Next

The Pro’s and Con’s of Photochromic Lenses

Photochromic lenses are nothing new, first making their debut in late 1960s. They remain a popular option because of their convenience; the “cool” factor plays a part in their popularity, too.

Photochromic lenses are a pretty cool piece of eyewear technology. They may not be new, but they’re not nearly as common as traditional lenses, and when people first see them in action they always seem to get a kick out of it.

These lenses automagically darken when exposed to sunlight, making them convenient to wear whether you are inside or out. They are also often referred to as “transition lenses” because of how they transition from clear to dark.

Today, you can get photochromic lenses for just about any application and prescription. We get a lot of people asking us about photochromic lenses and whether or not they are a good fit for their lifestyle. We thought we’d put our “pen to paper” and outline a bit about the pros and cons of photochromic lenses.

Photochromic Lens Pro’s


  • You can get them in nearly any prescription and application – Monofocal, bifocal, trifocal, progressive, high index, and more… there’s a photochromic lens available for just about everybody.

  • They protect your eyes from UV radiation – Almost all photochromic lenses available today are rated for UV 400 protection (meaning they block light up to 400 nanometres, or about 100% of UV light).

    As you may know, UV light has been linked to serious eye conditions such as cataracts, macular degeneration, and even ocular cancer.

  • They are ultra convenient – Many people only want to own a single pair of eyeglasses. With photochromic lenses, those glasses can also act as your sunglasses.

  • They darken according to light conditions – The more intense the light, the more they darken. This means that they are unlikely to be too dark or too light. We find that they are always quite comfortable to wear.


Photochromic Lens Con’s


  • They can take anywhere from 30 seconds to several minutes to darken – Most modern photochromic lenses darken in under 45 seconds, though some can take a little longer than that. Most will continue to darken for around 15 minutes before reaching “peak darkness”.

  • They darken even under cloud cover – Since the photochromic lenses darken because of UV light (which easily passes through clouds), they darken when it’s cloudy.


Not all photochromic lenses darken when behind a windshield – UVA light is actually blocked by glass, meaning that unless the lens was designed to darken with UVB light, they won’t darken when you get into your car.

There are many photochromic lenses that do darken behind a windshield. If this is important to you, make sure you opt for a pair that won’t give you sass when you’re behind glass.