Ever wondered how our sunglasses work? We can’t stress enough how important proper eye protection is. The danger of UV radiation are becoming increasingly known, one that you shouldn’t underestimate. We’ve recently covered some ground on what the dangers are of UV-rays. UV-rays carry the most harmful side effects of the sun, which can result in both short and long-term ocular degeneration or impairment. Fortunately all sunglasses these days offer a 99-100% protection against UVA and UVB light, with wavelenghts of 400nm, without breaking bank. Expensive sunglasses, cheaper sunglasses, they all fundamentally work just as well. Find out what the real reason is behind these price differences? Read our blog about 5 misconceptions about cheaper sunglasses. Many experts in the industry recommend to always look for sunglasses labeled as UV400.
What do sunglasses do?
- Sunglasses offer full protection against harmful ultraviolet rays in sunlight
- Ultraviolet (UV) light damages the cornea and the retina and it can cause a variety of short and long-term damages to your eyes.
- Sunglasses provide protection against intense light
- When there is too much light, your eyes will try to counter this by closing the iris. Once it has closed the iris, the next step will be squinting. If there is still too much light then damage to the retina may appear. A good pair of sunglasses has the right darkness to fence of the light as it tries to enter your eyes.
- Sunglasses (can) provide protection from glare
- Depending on what type of sunglasses you are wearing, polarized lenses can eliminate a great deal of glare coming from the water, from the road or from the snow.
- Sunglasses can eliminate specific frequencies of light
- Certain frequencies of light on the color spectrum may blur vision, enhance contrast or stimulate your body to go to sleep or stay awake. Depending on the brand, the type of lens and use, lenses may be tweaked and put together with certain coatings and materials to block or enhance these frequencies.
Understanding how light works
Blocking harmful UV-rays is just one function of the sunglasses you are wearing. In order to understand how lenses work and why they look the way they do, you first need to get a better understanding of how light works. The sun produces light and a light wave consists of electromagnetic energy, which is measured in wavelength. These wavelengths range from 400 tot 700nm. Of the light that is visible, violet us the most powerful and just above violet there is ultraviolet (UV) light, which turns out to be dangerous for your skin and your eyes.
How do sunglasses block harmful UVA and UVB rays?
Annie Liao has made a very informative infographic on how in general sunglasses work. The concept behind this is similar as to how our products offer the same protection to harmful UV radiation, but depending on what type of products you are looking at, not all layers, coatings and finishes may apply.
How do sunglasses deal with glare?
The brightness of light is measured in lumen. So the bigger the lumen, the bigger the chance of glare. When you try to look at the sun you will notice the glare coming right at you. Sunglasses can tackle this to a certain degree if there is a polarized filter in the lenses. We have previously covered some ground on polarization and what benefits or drawbacks there are, so we’ll keep it short and simple for this article.
Reflection happens both horizontally and vertically. Usually we are dealing with horizontal light because we are sitting or standing upright. For example when we drive, look over the water, or go skiing and snowboarding. Sunglasses with polarizing lenses contain a special filter that absorbs these horizontal reflections. In other words, instead of light reduction, polarized sunglasses absorb horizontal light. Offering a much smoother viewing experience.