Oki C3520 - Manual (Page 103)

Maintenance > 103
3. Gently wipe the LED head surface (1) with LED lens
cleaner or a soft tissue.
4. Close the printer top cover and press down firmly so that
the cover latches closed.
5. Gently lower the scanner on to its supports.
1
CAUTION!
Do not use methyl alcohol or other solvents on the
LED head as damage to the lens surface will occur.