How to Make the Anti-Reflective Coating Last on Your High Index Lenses
High index eyeglasses are thin, lightweight, block harmful ultraviolet, and fit a wide variety of stylish frames. No longer must someone “advertise” their high prescription level by wearing glasses with thick coke bottle lenses. But the materials used for high index lenses have a drawback: they are highly reflective.
This problem is more than a cosmetic issue of others not able to see your eyes because of reflected light. It affects your safety. Reflections off the inside lens surface and the associated glare interfere with your vision. This places you at a higher risk of injury from car accidents. Reflected light off the outer lens surface means less light gets through to your eyes. This reduces your ability to see at night, especially when driving.
An Anti-Reflective (AR) coating added to your high index lenses eliminates the above problems. However, there is one catch. The coating requires extra care on your part to prevent it from peeling and getting scratched. The first step in extending the life of an AR coating is dealing only with quality eye-wear providers. Eye-wear from a low quality provider means their AR coatings may not last for even a few months. The second step is taking good care of your lenses. Here are four suggestions:
Avoid Dusty and Dirty Environments
Dust and dirt buildup on your high index lenses interferes with clear vision. This requires cleaning your lenses, and each time you do this, there’s a chance the AR coating can get scratched. The best way to avoid constant cleaning is avoiding dusty environments. Damage to the coating is possible when outdoors in windy and dusty conditions. The wind-driven dust impacts and erodes the coating.
Keep Your High Index Eyeglasses in a Case
While this is a common enough suggestion, it’s nevertheless an important one. The most common ways that lenses (and their AR coatings) get scratched are when they drop to the floor, are placed in a pocket, or placed lens down on a dirty surface. Your high index eyeglasses should be in one of two places: either on your face or in a case. The case protects them from dust and mechanical damage. Finally, keep the inside of your case clean. You don’t want to expose your high index lenses to a dusty and dirty environment, which is exactly the situation inside a dirty case.
Keep Your High Index Eyeglasses out of Hot Cars
The inside of a car parked in the summer sun can reach over 200 degrees Fahrenheit. The different components of your high index eyeglasses, including the AR coating, expand in the heat at different rates. This causes movement between the coating and lens surface as well as between your glasses’ other components. This habit alone can cause some AR coatings to peel off the lenses.
Properly Clean Your High Index Lenses
This means not:
- Using clothing. Wiping your lenses against your shirt or other article of clothing exposes the AR coating to abrasive fibers and abrasive dust and dirt in the clothing.
- Dry wiping. Dry wiping dust off your lens grinds the dust particles into the AR coating, which abrades the surface.
- Using paper. Paper towels are abrasive, and contain adhesives and dyes. Tissue paper easily breaks apart when wet, leaves small fibers, and is too rough.
- Using window cleaners. Window cleaners are meant for glass, not plastics or your AR lens coating.
- Using any cleaning agent not meant for your AR coating. The only exception to this is Dawn dishwashing soap. Otherwise, use only the recommended cleaning agent for your AR coating. For drying purposes, use a microfiber cloth.
If you have questions about proper care for your AR coated lenses, or need answers about anything to do with high index lenses, please contact us.