Eyeglasses | Optical Center SmartBuyGlasses CA

How to Care for Transition Lenses

What are Transition Lenses?

Photochromic (or photochromatic) lenses are a certain type of lens that react to different levels of UV light. You may also be familiar with this technology under another name: transitions. They’re essentially sunglasses and prescription glasses all rolled into one.

Time to delve into a bit of history. The earliest versions of photochromic lenses used certain compounds (namely silver chloride or silver halide) which would darken upon exposure to UV light. These days, photochromic lenses use proprietary photochromic dyes that have been chemically processed to darken the lenses when exposed to UV light.

When exposed to bright light on a sunny day, molecules in the lens react and become darker as quickly as 35 seconds after exposure - offering protection from intense solar radiation. As light levels decrease, these molecules go back to their original state and become transparent once again. At night or inside, when there’s an absence of high-intensity UV light, the lenses appear clear.


How do Transition Lenses Work?

Photochromic lenses contain special molecules (typically compounds between silver and halogen elements)  that change shape and absorb light when exposed to UV rays. This reaction causes the lenses to darken in sunlight. When taken away from UV light, the process reverses, causing the lenses to gradually become lighter.

The lenses typically take around 15 minutes to completely darken, although some change will be seen within the very first minute. Photochromic lenses react when in direct contact with UV light and offer a great alternative to switching between glasses and prescription sunglasses. In brighter conditions, these photochromic adaptive lenses will darken and as conditions become darker, the lenses will become clear once more.


Who needs Transition Lenses?

Photochromic lenses only react when directly exposed to UV light. This means that in an office or home environment, they will remain clear. So, if you’re often moving from inside to outside, these glasses will ensure you don’t need to lug around multiple pairs of eyewear. Transition lenses help you see objects of differing size, contrast and, most importantly, brightness. Overall, photochromic lens users tend to see better in a greater range of light conditions.

Transitions lenses can be used by people with a whole range of different vision issues. They’re available in a variety of designs and materials, from standard and high index versions to more rugged, impact-resistant materials. Another great feature of transition lenses is that they can be used for single vision lenses as well as progressive lenses.

We recommend transition lenses to anyone whose vision is at risk when exposed to light and UV rays. This can include people who have specific medical conditions such as cataracts and diabetes that affect night vision and sensitivity to contrast. It’s also worth noting that some medications are known to lead to sensitivity to bright light and sunlight - thus, we strongly suggest the use of transition lenses to such patients as well as those who recently underwent surgery for their eyes.

Children are also rather well-suited for photochromic lenses as they spend a lot of time outdoors and are exposed to solar UV rays more frequently. The crystalline lenses in their eyes are yet to fully develop as well. They may allow UV light to penetrate through, potentially causing damage in this formative age.



Photochromic Sunglasses

Transition sunglasses are normal sunglasses that are fitted with photochromic lenses. Their lenses behave the same way - i.e. becoming transparent indoors and dark outdoors. Some photochromic sunglasses lenses, however, do come with tinted lenses as a ‘base’ and gradually become darker. These are typically worn for outdoor use only. 

It is very important to note that some photochromic lenses may not be suitable for driving. This is because car windshields are coated with a UV-blocking layer, which may prevent your photochromic lenses from adjusting to light conditions inside your car.

You can explore some of our best selling photochromic models including the Oakley RadarLock Path, Ray-Ban RB3447 Round Metal and Serengeti Sestriere Polarized.


Photochromic Lenses vs Transition Lenses

Transition lenses are the commercial term for photochromic lenses. This is the only difference between photochromic and transition lenses. The term ‘Transitions® Lenses’ refers only to photochromic lenses manufactured by Essilor. Any other brand of photochromic lenses manufactured by HKO, Hoya, or ZEISS, for example, will operate and work in exactly the same way.


Benefits of Transition Lenses

  • - They’re cost-effective: With a pair of photochromic lenses, you save the cost of buying a pair of eyeglasses and prescription sunglasses as you have the functionality of your eyeglasses and protection from the sun, packed in one pair.

  • - Convenience: Not only is it cost-effective, but it’s also convenient as your transition lens works by itself when you’re in different light settings and you don’t have to switch between your eyeglasses and sunglasses every now and then.

  • - Less risk of losing your glasses: With the convenience of having an all-in-one pair of eyeglasses, you’re far less likely to lose your glasses as you’re probably always wearing them.

  • - Flexibility. Transition lenses are highly flexible and help reduce eye fatigue, glare and strain from the constant variations in light.

  • - Protection from UV rays: Transition lenses aren’t just tinted, they’re meant to protect you from the harmful UV rays of the sun, helping you to maintain the health of your eyes.

  • - Choice: At SmartBuyGlasses, you can find a huge variety of photochromic eyewear designs from which to choose - aviator sunglasses, butterfly frames, cat-eye frames, oval frames, oversized frames, pilot frames, rectangle glasses, round glasses, square frames, wayfarer glasses, Asian fit glasses, full-rim frames, half-rim frames, rimless glasses and more. No matter what your budget or style, you can find what you love at SmartBuyGlasses.


Cons of Transition Lenses

  • - Car windshields come built-in with anti glare films that block out most of the UV light entering the vehicle. This negates the effects of the transition lenses, as they register this environment as “non-lit” when in reality, the direct sunlight might be very bright. This might be unsafe for the wearer, even if they’re not legally required to wear prescription lenses while driving.

  • - Transition lenses may not be polarized. Subsequently, they may not be able to reflect harsh glares. If you anticipate that you’ll constantly be outdoors in a high-glare environment, we recommend some polarized prescription sunglasses in a wraparound style.


Steps to Clean and Take Care of your Transition Lenses

We wear our glasses all day, every day, no matter where we go. It’s crucial that the lenses be as clean as possible to avoid smudges, stains and dust. Here’s how you can clean your transition lenses to maintain their effectiveness.

  • - Start by wetting your lenses with lukewarm water. Particles such as dust and dirt stick to your lenses. This means that there’s a high chance that if you dry wipe them, you can move them around and even create micro-scratches on your lenses, hence lessening the life of your lenses. Avoid using ammonia containing household chemical cleaners on your lenses as these can degrade this type of coating.

  • - Gently blot your glasses with a good quality microfiber cloth. Gentle dabs are all you need. Avoid paper towels, tissues, napkins or the ends of your shirt. While they might seem soft, their textured surfaces may scratch your lenses, deteriorating their coating. All SmartBuyGlasses eyewear comes with optical cloths specifically for this purpose.

  • - After your transition lenses are dry, apply a tiny drop of mild dishwashing soap to your fingertips. Wet your lenses again, using your fingertip to spread it around and eliminate any oil and finger smudges that might be left.

  • - Blot the glasses to dry again.

You can expect transition lenses to last just as long as the prescription, if not longer. Photochromic lenses are effective for at least 3 years (or more, if well-looked-after). After that point, you may notice that it takes longer for the lenses to switch from the dark-tinted to clear modes or vice versa. 

Useful tip: a yellowish tint at the edges of the lenses might be a sign of worn-out transition lenses.


There’s nothing not to love about transition lenses! In addition to correcting your vision, you get automatic UV protection on the go. Take the next step and select transition at checkout to turn your favourite designer eyeglasses into protective photochromic sunnies!