UV400 means the lens blocks ultraviolet radiation up to 400 nanometers, covering the full range of UVA and UVB rays. It's the most important spec in a pair of sunglasses, and it has nothing to do with how dark the lens is.
Why the UV filter matters
You can't see or feel ultraviolet radiation in the moment. Its effect on the eye is cumulative: repeated exposure over the years is linked to problems such as cataracts. Sunglasses exist, first and foremost, to stop that radiation.
The sun emits UV all year round, even on cloudy days, because much of it passes through the clouds. On snow, water and sand, exposure increases due to reflection.
Lens tint is not protection
A dark lens reduces visible light, which makes your pupils dilate. If that lens has no UV filter, more radiation gets in than with no sunglasses at all. That's why dark sunglasses without a filter are worse than wearing nothing.
The reverse is also true: a light or gradient lens can offer full UV400 protection. Color and tint intensity are a matter of comfort and style; protection depends on the filter.
What is blue light?
Blue light is the highest-energy part of visible light. Its main source is the sun; screens emit it too, in much smaller amounts. Outdoors, filtering it improves contrast and reduces glare on very bright days.
And the infrared filter
Infrared radiation is what we feel as heat. Some lenses add a filter that reduces it, designed for people who spend long stretches in the sun.
What ORBITAL lenses filter
Every one of our lenses is VSL™ (Vision System Lens), without exception. Here's what each includes:
- UV400: on every lens.
- Blue-light filter: on every lens.
- Infrared filter: on select lenses.
- Polarized: on select lenses. What it is and when it's worth it: Polarized Sunglasses: What They Are, How They Work and When They're Worth It.
Each product page lists the filters on that lens. Learn more about VSL Technology.
How to tell if sunglasses have UV400
You can't tell by looking: a lens with a filter and one without look exactly the same. There are two ways to know.
- The manufacturer states it. It should appear on the product, the packaging or the spec sheet.
- Measure it. Many optical shops have a UV meter and can check it on the spot.
FAQ
Are UV400 and 100% UV protection the same thing?
In practice, yes. Both mean the lens blocks UVA and UVB rays.
Does the UV filter wear off over time?
In a quality lens the filter is part of the lens itself and doesn't wear off with normal use. What does affect your vision is scratches, so clean your lenses with a microfiber cloth and keep them in their case.
Do I need sunglasses in winter?
Yes. UV radiation is present all year, and snow multiplies it through reflection.
