I can't stand having smudged eyeglasses, but I'm also lazy about cleaning them properly. Usually, I just wash the lenses with handsoap and dry them on my t-shirt. The result is that my lenses are mostly smudge-free, but they are fairly scratched. My glasses, and my vision, would be better off if I followed Laurence Tratt's method that he adapted from instructions on cleaning camera lenses. From Tratt's blog:
- I start by wiping all the dust off with a (synthetic) camel hair paint brush (these work for me). Intuitively, this means that when I wipe the lens later there is no dust to act as an abrasive.
- I then wipe the lens with a dry microfibre cloth (I don't use water or breath). I bought a pack of 10 small cloths in individual bags so that I can replace the cloth every week, and only wash them (with a little bit of white vinegar) every 10 weeks. Keeping the cloths in their bag, rather than out in the open, means that they don't pick dust up. I rotate cloths frequently because they inevitably pick up dust and oil: once a week might be unnecessarily often, but it makes it a simple part of my routine.
- Once a week, I use an oil remover (I use Residual Oil Remover but that might be overkill) with the microfibre cloth (and afterwards put that cloth in the "to wash" pile). One or two drops on the cloth per lens side seems quite sufficient. I could perhaps do this less frequently too, but again, once a week makes it a simple part of my routine.
- Once every 6 weeks or so, I use an ultrasonic cleaner to clean all the goop that builds up around the frame (without doing something this becomes hideous over the lifetime of a pair of glasses).
How I Clean my Glasses (Tratt.net)