Do Not Buy Sunglasses Without These Two Functions
1. Uv Protection Function
Our First Priority Should Be The Uv Protection Function Of Sunglasses.
Many People Will Subconsciously Think That Any Sunglasses Have Uv Protection Function, But In Fact, Many Cheap And Low-quality Sunglasses On The Market Not Only Can't Block Uv Rays, But Also Will Seriously Reduce The Lens Transmittance.
What's More, These Glasses May Also Damage Your Eyes. The Human Body Has An Instinctive Reaction Of Self-protection. When The Eyes Encounter Strong Light, The Pupil Will Naturally Become Smaller, Which Reduces The Ultraviolet Energy Entering The Eyes. Once You Wear Glasses Without Uv Protection Function, The Pupil Will Be Enlarged. In Addition, Such Glasses Do Not Have The Function Of Isolating Ultraviolet Rays. At This Time, The Eyes Are Open. The Damage To The Eyes Can Be Imagined If Ultraviolet Rays Enter.
So, How Do We Judge Whether Sunglasses Have Uv Protection Function?
When Buying Glasses, We Can Pay Attention To The Marks On The Glasses. Generally Speaking, Uv Resistant Sunglasses Will Have Obvious Marks Such As "uv Resistant", "uv400" On The Label Or Lens.
"uv Index" Is The Effect Of Filtering Ultraviolet Rays, Which Is A Very Important Standard For Purchasing Sunglasses. The Light With The Wavelength Of 100nm-400nm Is Called Ultraviolet Light, But The Light With The Wavelength Of 100nm-280nm Is Almost Completely Absorbed By The Ozone Layer And Cannot Reach The Earth's Surface. Therefore, The Ultraviolet Protection We Generally Say Refers To The Light With The Wavelength Of 280nm-400nm. Generally Speaking, 100% Uv Index Is Impossible. The Uv Index Of Most Sunglasses Is Between 96% - 98%.
The Sunglasses Labeled "uv400" Can Reach The Level Of More Than 90% Uv Protection. The Lenses Are Specially Processed To Block Ultraviolet Rays With A Wavelength Less Than 400nm.
2. Polarization Function
Secondly, We Should Pay Attention To Whether The Sunglasses Have Polarizing Function When Purchasing.
The Lens With Polarizing Function Can Effectively Eliminate And Filter The Scattered Light In The Beam, So That The Light Can Be Put Into The Visual Image Of The Eye On The Light Transmission Axis Of The Normal Track, So That The Visual Field Is Clear And Natural, Playing The Role Of Filtering Strong Light And Efficient Eye Protection.
Like The Principle Of Blind Curtains, The Light Is Adjusted Into The Same Direction And Enters The Room, Which Naturally Makes The Scenery Look Soft And Not Dazzling.
This Function Can Not Only Avoid Glare And Glare During The Day, But Also Play A Great Role At Night. For Drivers Driving At Night, The Flash Of High Beam And Strong Light Will Cause Short-term Blindness To The Eyes. At This Time, Sunglasses With Polarization Function Play A Great Role.
