Have you ever owned a pair of glasses covered in scuffs and scratches? I know I definitely have. I wore the same pair of glasses for over 5 years, and towards the end, the scratches were becoming so bothersome that I decided to get a new pair, which were going to be kept free. But how?
Back in the day, eyeglass lenses used to be made of glass. Glass is a fairly scratch-resistant material, and with optics being relatively new, scratches weren't exactly the biggest concern of the time. Over time however, as technology permitted change, materials that lenses were made of also changed. Plastics started being put into use, as plastic is typically lighter than glass. Even polycarbonate (a material that won't shatter on impact the way glass and regular plastic lenses will) started to see use in optical lenses. This of course created a problem, as both those materials are not resistant to scratches. Scratch free coatings were designed that help to a degree, but still today we are fighting with lenses that scratch easily, despite improvements in technology and scratch-resistant coatings.
The first thing to look at is what causes glasses to be scratched in the first place. Certain things are unavoidable. Accidents for example can leave gouges and scratches in a lens. Being careful with your glasses (both while wearing and storing) is the best you can hope for to avoid this.
One of the biggest causes of scratched glasses though, is cleaning. Yes, simple "harmless" cleaning slowly destroys lenses more often that you might imagine. There are a few ways cleaning can hurt a lens. First, for those of you using your shirt tail to wipe off a lens, stop now. Not only does dirt become embedded in clothing rather quickly, but fabric softener can leave a film, and some materials just plain aren't nice to plastic, and will leave sure scrathes. Using paper tower, or even toilet paper and kleenex can also put fine scratches in a lens. You won't notice it at first, but after a year or two, many fine scratches will become evident. These are wood-pulp and paper-based products, and are not recommended, even by the manufacturers. Don't believe me? This excerpt was taken directly from the FAQ on Kleenex's own web site:
Can KLEENEX Tissue be used to clean eyeglasses? While we know that many consumers use KLEENEX Tissue to wipe or clean their lenses, we have not tested KLEENEX Tissue for this purpose; therefore, we cannot recommend it. We suggest that consumers check with their lens care providers for the best method of cleaning their lenses.
Now I've got nothing against Kleenex. In fact, I give them a lot of respect for addressing this on their website. If anything, I trust them more as a company for being honest and truthful about the subject, despite that fact that it obviously could reduce their sales. Basically, I'm just quoting this to keep a needless debate from happening. Even the manufacturer of the most popular soft tissue recommends against using their product to clean glasses.
Micro fiber cloths
So what's better than kleenex? Micro-fiber cloths. You may or may not have heard of these. They're sold by most reputable eyeglass retailers. They're usually made of a combination of nylon and polyester and are made up of extremely small fibers of that material. They are the best material you can use to clean anything prone to scratches, as the cloth itself is almost guaranteed not to scratch. There is still a problem though, if there is any sort of dirt or debris that gets caught in the fibers, that dirt or debris can still scratch.
Wet vs Dry
Never clean glasses dry, no matter what material you use. Liquids act as a lubricant, and help reduce friction, and the risk of scratching. Water works great, although there are spray cleaners you can buy from most optical places (usually made of water and mild detergent or a miniscule amount of alcohol)
Windex and other Detergents
Most windex and glass cleaning products contain ammonia. Ammonia is great for cleaning glass. However, it can destroy coatings on glasses pretty quickly. Windex is a big no-no. Many other detergents are also strong enough that over time they will wear off your coatings. Since coatings are designed to protect the lens from scratches, once those coatings are gone, your lens will be even more vulnerable.
The best way....
Now, the best way to clean your glasses is.... are you ready for this...? Soap and water. Yes, that's the big secret. Don't spray windex on your glasses, don't breathe a fine mist on them and use a tissue, just use a mild dish soap and water. Why? First of all, water will remove dirt and debris from your lens, without scratching your lens. Think of it this way - if you had bits and pieces of miniature glass shards and splinters dumped on your arm, between these two options, would you rather (a) try and rub them off with a tissue or even a micro-fiber cloth, or (b) put your arm under a tap of water and rinse them off that way. No, it's not the best analogy, but you get the idea. Make sure you don't use hot water, as it has been known to "crack" coatings in some cases. Cold or warm water should be fine. Using soap such as a mild dish soap isn't going to eat away at any coatings.
Now how about drying them? If you are one of the lucky ones who got coatings on your glasses that are water-repellent, you can usually run them under water, and slowly remove them, leaving the lenses spot free. If you end up with a couple drops left, you can probably dab them off lightly with a tissue without causing too much harm. Unfortunately, if your glasses didn't come with any coatings (or with any that are water repellant), you're probably going to have to rub them with something (micro-fiber cloth) to dry them. The good news is that as long as the cloth doesn't have debris already engrained in it, you've hopefully already washed any existing debris from the lenses, so it shouldn't scratch anyway.
In short, keep the following in mind when cleaning:
Despite every effort you make, accidents and mishaps can damage your lenses. However, in most cases, changing your cleaning methods will keep your glasses looking like-new for years.
Disclaimer: All information on this page is to be taken as opinion and not as fact. I disclaim all liability for anything that happens to anybody as a result of this existence of this page, any other pages on this site, or any other companies, people, places, or pages, that have been mentioned, referred to or linked to. Use this information at your own risk.