Man wearing a pair of tinted frames on a sunny day

Can you activate transition lenses without sun?

5 Feb 2024

As a glasses wearer, you might already be aware that photochromic lenses, or light-adaptive transition lenses, are dual-purpose and function as both fully clear glasses indoors as well as a pair of sunglasses when exposed to bright sunlight outdoors. If this is your first experience with transition lenses, you might be curious to know how they work. In this blog post, we’ll enlighten you on how to activate transition lenses and help you familiarise yourself with them a little more.

Pair of round tortoiseshell frames transitioning from clear to tinted lenses

How do transition lenses work?

Transitions® Light Intelligent Lenses™ are a type of photochromic lenses. They consist of tiny photochromic molecules. The lens remains completely clear until it is exposed to UV light. At this time, the molecules move, alter their shape and soak up the light. This chemical reaction causes the molecules to change and they get darker, turning into a type of sunglasses tint. The lens will stay dark whilst exposed to UV rays and then the molecules will return the lens to its original transparent state as soon as it is removed from bright light.

Just be aware, that even though transition lenses transform from clear to dark very quickly, if you go back indoors after being outside, it can take a little while for your lenses to return to their clear state. Make sure you’re aware of your surroundings and if the room is dark, take care to keep yourself safe.

How to activate transition lenses

There are two main methods you can use to activate transition lenses. Keep reading to find out how you can make the lenses darken.

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Expose your lenses to bright sunlight

The easiest way to activate your transition lenses is by exposing them to UV light. Transition lenses are designed to adapt to the light around them so they may not always go totally dark. The extent to which they darken varies according to the amount of UV light they are exposed to. If you’re located somewhere that has a very low amount of light, the lenses will not go as dark as they would in direct sunlight.

Transition lenses are multi-purpose and ideal for adventure lovers and people who spend a lot of time outdoors. They function in all weather conditions even when it is cloudy and cold outside. The lenses seamlessly adapt to changing light, so you can get on with your day and focus on the task at hand knowing that your eyes are protected. There is no need to switch between a pair of glasses and sunglasses.

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Use artificial UV light

If you’re keen to know how to activate transition lenses without sun and can’t wait to see them in action, try shining a torch on them. Torches that project UV light are easy to get hold of online and in most hardware stores.

However, we would recommend that you be patient and wait for the lenses to darken naturally. This way you’ll have a chance to see them perform at their best.

Do transition lenses work through windows?

Man wearing a pair of ombre colour frames in front of a computer screen

Most windows are designed to block UV rays. For this reason, you might find it more difficult to activate transition lenses at home. However, they are very convenient if your work environment is exposed to a lot of natural light. Especially in a very modern office environment, because you will not have to worry about them darkening when you’re indoors. Especially when you’re moving around or focusing on your computer screen.

Are transition lenses suitable for driving?

Our standard light adaptive lenses and Transitions®Signature®GEN8™ are intended for general use and are not specifically designed for driving. It is best to invest in Transitions®Drivewear® or Transitions®XTRActive®. These lenses are your best bet as they will enable you to see clearly out of your windscreen and they are designed to keep you protected whilst driving.

Transitions®XTRActive® and Transitions®Drivewear® work differently. Transitions®XTRActive® lenses are ideal for everyday wear and also safe to drive at night with. Compared to other photochromic lenses, the molecules in Transitions®XTRActive® lenses react to both UV light and natural (visible, clear, or white) light. This means they are able to darken behind the windshield of your car.

Transitions® Drivewear® lenses, meanwhile, combine the benefits of photochromic technology and fixed polarisation. The polarisation eliminates glare reflected off the road and other vehicles. Meanwhile, the photochromic technology alters the colour and tint of the lenses according to the light conditions. They are a type of sunglasses specifically designed to help you drive safely on the road during the day.