Glasses take a lot of punishment over the years. If you use spectacles daily to aid your vision, they will need regular maintenance. Glasses used less regularly, such as sunglasses, may be kept in a drawer or left lying around until needed. However they are used, glasses protect your eyes from everyday dirt and dust, cope with sweat and oils from your skin and probably get handled several times a day. It's no wonder they need regular cleaning and careful handling if they are to stay in tip-top condition. Regular cleaning of spectacles will ensure clear vision and help give them a longer life before they need repair or replacement. It's so easy to cause damage by cleaning your specs incorrectly or using inappropriate cleaning materials. It's helpful to know the best way to clean your glasses. Here are some valuable tips to help you keep your glasses as good as new for as long as possible.
Before cleaning your lenses, it's a good idea to wash your hands. Oils and dirt are easily transferred to glass and polycarbonates; if they are on your hands, they are likely to end up on your lenses. Any gritty material on your hands or fingers may even cause tiny scratches on the lens surfaces, so it's best to start properly. It's a bad idea to lick lenses to clean them. It's unhygienic, and saliva is not good at cleaning anyway. You can run glasses under a gentle stream of lukewarm tap water. Don't let the water get too hot, though, as this may damage some coatings. It will remove dust and debris but is unlikely to affect grease stains or smears. Adding a tiny drop of dishwashing liquid will help but be sure to remove all soapy traces or the lenses will smear when they dry. Avoid using soaps or cleaners that contain ammonia or other harsh chemicals. Your lenses may have specialist coatings sensitive to the strong chemicals often used in household cleaners. Take care to hold glasses properly when cleaning them. Do not hold glasses by the arms or hinges when cleaning. Pressure applied on lenses by rubbing them will strain the hinge and may bend the arm out of shape. Holding the frames firmly across the bridge between your forefinger and thumb is best. It allows plenty of room for cleaning without damaging more delicate eyewear parts. Sometimes dirt builds up around the hinges or between the lenses and the frame. Use a soft toothbrush and warm soapy water but be careful not to touch the lenses with the bristles.
Cleaning sprays are ideal for giving lenses a thorough cleaning. They usually come in small pump action bottles. Many spray the cleaner directly onto the lens, but this is not a good idea. Lenses may have tiny drill holes, which can cause damage over time if filled with cleaning fluid. Far better to spray a microfibre cleaning cloth and apply this to the lens. It ensures you clean the lens with just enough moisture to remove grease and grime. Specialist lens cleaners will be safe and effective on all lens surfaces, including coated lenses. Gently rub the lens in a circular motion with the cloth until the glass is clear, then wipe away any excess. If your lenses have anti-reflective (AR) coating, make sure the cleaner is approved for use on anti-reflective lenses.
Optical quality microfibre cloths are the best for cleaning glasses and spectacles. They are soft, lint-free and have no nylon hem that may cause damage. The higher the quality, the better the job. Cheaper cloths tend to break down with use, splitting the fibres and leaving lint residues. Good quality glass cloths are essential for a streak-free surface. Optical quality cleaning cloths are very soft, washable, easy to rinse and can be used on all sensitive surfaces such as cameras, laptops, mobile phones and even wine glasses. For best results cleaning cloths should be washed regularly, preferably lower than 40 degrees and without using a fabric softener. Using paper towels, tissues, dishcloths or clothing to wipe your lenses might appear more convenient, but this should be avoided. Paper towels are made from wood chip pulp treated with bleaching solutions and may produce tiny micro scratches in any lens surface coating. There is the danger of transferring dirt or debris onto the lens from your coat sleeve or other items on clothing which can result in microscopic scraping, even on modern polycarbonate lenses with a hard coating.
An alternative to cleaning sprays is lens wipes. Wipes are often individually wrapped, which makes them highly portable. You can pop a couple into your pocket or handbag for use at any time. Lens wipes allow gentle and thorough cleaning with no risk of damage. They are fast dying and give a streak-free finish. Good-quality lens wipes will be manufactured from micro-fine tissue and won't contain harsh cleaning agents. The cleaning fluid used in lens wipes is also designed to evaporate quickly, avoiding the need for a cleaning cloth. Cleaning cloths can themselves get dirty, picking up dust and grime while spray bottles take up carrying space. Pre-moistened lens wipes on the other hand are small, often folded into even smaller sachets, very convenient and easy to use.
Ultrasonic cleaning is the gentlest and most effective way to remove dirt from lenses and glasses frames. A high-frequency ultrasonic cleaner is capable of cleaning with great detail. Ultrasonic cleaners use sound waves between 20 and 400 kHz to clean objects. The combination of ultrasonic waves with an appropriate cleaning solution can clean much more thoroughly and with far less abrasion than other methods. High-frequency sound waves promote cavitation bubbles which clean dirt from the surface of an object at a microscopic level, ideal for complex surfaces with crevices, cracks or parts that are hard to clean manually. It removes dirt, grease and grime to leave lenses crystal-clear glasses feeling "like new". An ultrasonic bath is the ideal cleaning system for spectacles, watches, jewellery and similar items.
Glasses with crystal-clear lenses are a joy to wear, with no smears, streaks or mist to spoil the view. But good care is essential, and a thorough yet gentle clean is needed regularly to ensure good vision and longer-lasting lenses. All spectacle lenses will get scratches from regular everyday use and exposure to the elements. Glasses will occasionally get dropped, misplaced or mishandled. After a few years, your glasses will need cleaning and, at some point, they will need professional attention to get rid of ingrained dirt and oily residue. The good news is that lens-cleaning products are reasonably priced and highly effective at keeping glasses clean. When handling glasses, hold them by the frames using both hands and when putting them away always place them upside down with the bridge at the bottom. This will reduce the risk of scratching your lenses. Store your glasses in a case when not in use to protect them and don't leave them somewhere hot such as near a radiator or in hot sunlight – specialist coatings can crack and peel.