Polarization and UV protection of sunglasses

Tuesday, February 9th, 2010 at 2:59 pm Post in Sunglasses

Some people wonder that if inferior sunglasses with poor UV protection are more damaging than wearing no sunglasses. Although there are no confirming cases, it is to some extent reasonable that low-quality sunglasses are more harmful. Customers should always select quality sunglasses for best comfort and vision. Besides sunglasses, large hats are also helpful in offering sunlight protection outdoors.

Sunglasses with CR-39R plastics can absorb about 88% of UV light and this number of polycarbonate lenses is 100%. However, sunglass lenses made of triacetate only absorb approximately 40% of UV rays. Lenses made from other acrylic materials have varying UV absorption abilities. To gain 100% UV protection, it is quite necessary to get sunglasses from trustful sources such as reputable companies, specialty sunglass stores or optical professionals.

UV absorption capability deserves the top priority in sunglasses selection. But lens color is also an important factor for some customers. Some colors such as neutral density gray will darken the surrounding environment but not affect the wearer’s color perception. Other lens colors may change color perception.

Polarized sunglass lenses block horizontal light and allow vertical rays, which is helpful during outdoor activities such as fishing, driving and so on. This type of lenses reduces glare by blocking reflection from smooth surfaces. Unlike anti-reflective coatings that can be applied to both indoor and outdoor lenses, polarization is mostly added only to sunglass lenses.