Lens tint can sometimes be a bit confusing when purchasing a pair of sunglasses, and understanding the importance – or lack thereof – of lenses tint can be easily misunderstood.
The first thing you need to know is that sunglasses lenses are constructed out of several different materials like polycarbonate, plastic and mineral crown glass. Each material has its advantages and disadvantages; however, as technology improves some of these differences are disappearing.
Polycarbonate lenses have traditionally been lighter than glass and therefore somewhat more popular than glass lenses. However, polycarbonate lenses have a number of deficiencies associated with them:
- Polycarbonate lenses scratch easily;
- Polycarbonate lenses are more frequently associated with visual distortion;
- Applying lens coatings and tints is more difficult with Polycarbonate lenses.
Plastic lenses preceded polycarbonate lenses and were used because of their lighter weight. However, long exposure to ultraviolet radiation can change the molecular structure of plastic lenses over time, and they can warp and become misshapen with exposure to high temperatures.
Mineral Crown Glass Lenses
Mineral Crown glass lenses are also known as high-index lenses, and with modern technology they have become much thinner, and therefore lighter, than earlier glass lenses. This is due to the higher refractive indexes now available in glass lenses making them at least 50% thinner than conventional plastic lenses.
High Index Mineral Crown Glass Lenses have many benefits:
- Glass lenses will keep the wearer’s eyes cooler even with long hours of wear in bright sunlight;
- Glass lenses are both more impact and more scratch resistant than other lenses;
- Glass lenses are easily tinted and accept special coatings more easily than other lens materials.
Lens tint is sometimes confused with how dark the lenses are, and some people feel that the darker the lenses the more effective they are. Unfortunately this is a false assumption.
The dangerous rays you want to protect your eyes from are ultraviolet light rays (uv radiation), and these light rays are not in the visible light range. Therefore it is not how dark or light the lenses are that determines their effectiveness in blocking these harmful uv rays, but rather the coatings applied to the lenses!
The Importance Of Lens Tint
The importance of lens tint has to do with visual acuity – your ability to see objects through the lens clearly and with precision. Each lens tint relates to a specific issue the wearer may encounter. Some of these relationships are as follows:
- Neutral Grey lenses are considered the best for true color reception and the least amount of distortion;
- AGX, or lenses with a slight green tint, are also provide excellent visual acuity with little distortion, but are slightly more effective in a green environment like a forest;
- Tan lenses are very effective in low visibility conditions such as fog and haze;
- Other lens tint colors have more to do with fashion that with sunglasses performance.
The bottom line here is you need to be better informed about lens tint and how it impacts the performance of your pair of sunglasses rather than an assumption that darker is better.
In fact the Federal Aviation Administration (FAA) has issued a Safety Brochure titled “Sunglasses For Pilots: Beyond The Image” which provides even more useful information.
In addition recent research has shown that tinted sunglasses may help with migraine headaches.
Have a prosperous day!
p.s. Please share “How Important Is Lens Tint” with your friends using the buttons below. Thanks!