Cleaning laser lens; good idea?


I'm assuming that over time, dust and grit will slowly accumulate on the laser lens of CD (and DVD) players, given that the laser faces upwards, and dust will cling to CD's.
How and when does this become a problem, and is there an easy and safe way to remove this build-up?
carl109
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A make-up brush is a great idea, although I might get the wife to buy it for me; might get some odd looks!
I would assume natural fibres would be better, as synthetic might cause a static charge on the disc and attract more dust.
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Horse hair is used for camera lenses. make sure the bristles are not touched.