Light-reactive lenses are the best solution for anyone moving from indoors to outdoors throughout their day. The modern lens technology offers access to both clear lenses for indoor viewing and tinted lenses for bright sunlight — adapting to your setting and lifestyle.
To help patients fully grasp the value of light-reactive lenses to their lives and to their children’s eye health, many practices will promote UV and blue light protection (indoors and outdoors) as an inherent benefit. But is this a true benefit?
The Myth About Light-Reactive Lenses and Blue Light
Many believe that because a light-reactive lens has little-to-no noticeable color when in its clear indoor state, it cannot effectively filter indoor blue light. On the other hand, it’s easier for people to believe that blue light is definitely filtered outdoors, during its activated state — because the lenses have more evident color.
With a lack of intense color in the clear indoor state, blue light filtering is more difficult to grasp. Let’s clear it up for those who are wondering: “do regular light-reactive lenses really filter indoor blue light if it only has a 2% color tint indoors?”
The Truth Behind Light-Reactive Lenses and Blue Light
The answer is: color intensity of the deactivated light reactive lens has little to do with it. It's not the major determining factor of blue light filtration.
In their clear indoor state, no light reactive lens today has discernable residual color — except for specific versions made to become extra dark outdoors or in the car. Sensity Dark is a great example of this. However, most manufacturers will claim about 20% blue light filtration when their lens is in its clear indoor state.
Where does this blue light filtration come from if there is no visible color?
The answer here is, there is color — or rather, a hue that is barely visible. Every manufacturer will claim that their light reactive lens gets ‘completely clear’, however with the lens in its clear state, there’s a slight yellow hue of color in the lens. You can see this hue by holding the glasses directly next to a sheet of white paper.
Let’s focus on how color plays an important role in determining the amount of blue light protection.
The Role of Color in Blue Light Protection
Yellow is one of the best filters of blue light. Think of it like this.
Gray and brown polarized lenses stay in a consistent state of color. Brown polarized lenses are always lighter in color and allow more ambient light to pass through them than a gray polarized lens. And yet, brown effectively filters out much more blue light than their gray counterpart simply because they are brown.
In the end, it’s all about the color — not the intensity of the color itself. Brown is a more effective filter of blue light than gray, and yellow/amber are ideal for filtering blue light that causes eye fatigue and strain.
Make sure your patients know that just because their light-reactive lenses seem crystal clear, they’re actually still offering protection with a slight yellow hue. Blue light attenuation is an inherent property of ALL light reactive (photochromic) lenses. It is not something that is "special" or "new" it has always been there. With the prevalence of blue light concerns, especially since we are exposed to more indoors, the industry has been talking more about ways to mitigate it. Their light-reactive lenses are there to protect them, no matter what setting they’re in — or how clear their lenses appear to be.
Looking for ways to recommend blue light filtration to your patients?