I’ve recently seen a few posts for an eyeglass cleaner using alcohol, witch hazel or dish soap. Yes, those ingredients will get them clean, but there may be a price to pay in the long run. If you have any type of scratch resistant coating, or anti-glare/reflective lenses, the alcohol will make the coating break down and chip off. Dish soap can cause the lenses to become cloudy over time and can even damage the newer coatings like Crizol. Never, never use ammonia on glasses with polycarbonate lenses. In a short amount of time, the ammonia will cause the lenses to shatter with just a small bump.
Gentle hand soap is the best cleaner, just make sure it doesn’t contain any type of moisturizers or anti-bacterial ingredients. Wet the lenses apply a small drop of hand soap to your finger and rub in between your finger and thumb. Make sure glasses are wet, then rub the soap on the lenses. Rinse the same way by rubbing your thumb and finger over the lenses to make sure all traces of soap are removed. Use a microfiber cloth to dry and voila! Clean glasses!
Make sure to keep your microfiber cloth clean. You can throw it in the washer or wash it by hand, but DO NOT use any type of fabric softener sheets or liquid on it. Fabric softener will not only make it less absorbent, but will also smear your glasses and make it hard to clean off. Never use paper towels or napkins to dry off glasses. Any type of paper product contains small bits of OTHER substances–like shards of plastic and metal and other grit which will scratch your lenses, especially polycarbonate lenses. If you don’t have a microfiber cloth, any soft cotton linen will do.
My son has a pair of glasses that have the thick dark brown plastic frames. Those are a pain to keep clean because oil and dirt gather all around the edge of the frame. Even after washing and drying as said to above, they smear badly when he dries them. For this problem, we use a q-tip with a little bit of soap and clean all around the inside edge of the glasses and then rinse, rinse, rinse. Works perfectly!