Types of Sunglasses Lenses
When light reflects off flat surfaces such as water, snow, glass, sand or pavement it is reflected perpendicular to that surface. This reflective glare is very intense and has the potential to cause increased eye irritation, eye fatigue and in some cases restricted vision (It’s called Brewster’s Angle for you science folk out there). Polarized lenses, using horizontally aligned polarizing micro crystals, block all vertical light and protect your eyes from this glare. Polarized lenses are particularly suitable for water sports, cycling and driving where there tends to be a high degree of reflective glare, but they do not offer additional UV protection.
Photochromic lenses automatically adjust to changing light intensities to protect you in a wider range of conditions (science in action). These lenses actually get darker (to block more light) on bright days, and lighter when conditions get darker. A couple of caveats: The photochromic process doesn’t happen instantly, and it takes longer to work in cold conditions. Also, it doesn't work at all when you’re inside a car (the change in tint is activated by harmful UVB rays, which don’t penetrate your windshield).
Gradient lenses are tinted from the top down, so that the top of the lens is darkest. These lenses are good for driving, because they shield your eyes from overhead sunlight and allow more light through the bottom half of the lens so you can see your dashboard display clearly.
Double gradient refers to lenses that are also tinted from the bottom up: The top and bottom are darkest and the middle has a lighter tint. Double gradient lenses are a great choice if you want sunglasses that aren't too dark, but shield your eyes well against bright overhead sunlight and light reflecting off sand, water and other reflective surfaces at your feet. These lenses are a good choice for water sports.
Polycarbonate lenses are resilient, impact-resistant and a favorite among active individuals. Savvy parents choose polycarbonate lenses for children who may not take good care of their glasses. The durability of polycarbonate lenses makes them a good choice for rimless eyeglasses. Plus, polycarbonate lenses have built-in UV filters to help prevent eye problems such as macular degeneration (breakdown of macula) and cataracts (clouding of the eye lens).
Anti-reflective coating can reduce eyestrain caused from glare, reflections, and the "halos" you see around lights at night. It helps protect your lenses from scratches and smudges, and can repel dust and water. This coating makes your vision sharper and your eyes appear clearer behind your lenses. Some anti-reflective coatings reduce the amount of reflected UV from the back of your lenses, providing the best overall UV protection possible.
High Definition Lenses
For the first time, high definition or digital lenses, are now available. These advanced technology lenses offer a number of benefits over traditionally surfaced lenses.The quality of these of a high-definition lenses is similar to the quality of a digital camera. The higher the pixel count, the higher the degree of resolution resulting in crisp vision with unmatched depth and clarity.
High definition lenses also enable patients to enjoy up to 20% wider vision channels for both intermediate and near distance fields. This makes computer use and reading more comfortable and enjoyable. They are also available in sport and hobby-specific designs.
High-definition lenses are ideal for all patients who want to experience the latest in lens technology while those with high prescriptions and large amounts of astigmatism will experience the greatest wow factor.
Overexposing your eyes to ultraviolet rays can cause serious eye problems such as cataracts (clouding of the eye lens) and macular degeneration (breakdown of macula). The combination of UV protection that's built into lenses and applied as a coating can block 98-100% of transmitted and reflected UVA and UVB rays.
Coatings to Consider
Lens coatings are meant to protect your eyes from light or increase lens durability. Five common treatments to know about:
- Anti-scratch—generally a good idea for all—comes with 95 percent of plastic lenses.
- Anti-reflective coating costs ($50 to $100), often bundled with high-index and HD lenses, used to be hard to clean and smudge-prone but now has anti-smudge/anti-fog technology. If you have trouble seeing properly when on a computer, driving, and at night, consider anti-reflective.
- Ultraviolet protection ($20 to $100) a good idea for most people because the sun’s UV rays may boost the risk of cataracts. Most lenses already come with this coating; make sure yours do.
- Photochromic coating ($50 to $150) darkens in sunlight and shields you from UV rays. It’s helpful if you’d rather not carry separate sunglasses.
- Blue-light-blocking coatings ($30 to $180) are said to reduce exposure to computer screens’ LED light. (Some studies suggest that overexposure can damage the retina and increase the risk of age-related macular degeneration.
Thanks for reading, you can check out our super cool wooden sunglasses here. You can find out more about caring for your sunglasses here. You can read about the different types of wood used to make sunglasses here. You can read more about the advantages of Engleberts Premium Wooden Sunglasses here. You can read about why the sun is brighter in the fall here.