It's always a good idea to keep your scanner glass clean and free of dirt and grit.
Loose dust, pieces of paper, etc., can be blown off using a can of compressed air. (These cans are useful for a whole range of equipment; I try to keep one always available.)
The best way to keep your scanner clean is to use specialized optical-surface cleaning fluid along with an anti-static cleaning cloth. I keep them around because they are useful for a scanner and vital for a monitor (on which you should never, ever use a glass cleaner).
You can also, however, simply use a clean, soft, lint-free cloth along with a mild glass cleaner. Do NOT spray the glass cleaner directly on the glass; you could damage the components inside. Instead, spray a small amount on the cloth. Make sure the glass is absolutely dry when you're finished -- you don't want to leave streaks.
Don't panic, by the way, if you find a fingerprint on your glass. Because your scanner's focus is beyond its glass and to the document, the fingerprint shouldn't affect most scans.
More Printers / Scanners Quick Tips
Loose dust, pieces of paper, etc., can be blown off using a can of compressed air. (These cans are useful for a whole range of equipment; I try to keep one always available.)
The best way to keep your scanner clean is to use specialized optical-surface cleaning fluid along with an anti-static cleaning cloth. I keep them around because they are useful for a scanner and vital for a monitor (on which you should never, ever use a glass cleaner).
You can also, however, simply use a clean, soft, lint-free cloth along with a mild glass cleaner. Do NOT spray the glass cleaner directly on the glass; you could damage the components inside. Instead, spray a small amount on the cloth. Make sure the glass is absolutely dry when you're finished -- you don't want to leave streaks.
Don't panic, by the way, if you find a fingerprint on your glass. Because your scanner's focus is beyond its glass and to the document, the fingerprint shouldn't affect most scans.

