Light Microscope Cleaning Procedure
A few guidelines to follow
  • NEVER mix immersion oil types
  • ALWAYS clean immersion oil off oil lenses when you are finished with a scope (or at the end of a lab or end of the day)
  • Immersion oil that is left on a lens or mixed with other oils can solidify and ruin the lens
  • Do not use cotton swabs (Q-tips and the like) to clean lenses! The cotton fibers will scratch lens coatings. Dacron and foam-tipped swabs are OK.

Major component routine cleaning


  1. Routine disinfection of ocular to prevent transmission of conjunctivitis. Using a piece of non-linting lens paper soaked in 70% ethanol, lightly blot the surface to disinfect. Do not saturate the ocular! Air dry or use bunched lens paper to soak up the excess.
  2. Routine cleaning of oils and fingerprints and other contamination. First, use a duster and gently blow off the lens. Then, start with a bunched-up piece of non-linting lens paper dipped in lens cleaner (purple solution, aka Sparkle) and lightly blot the lens. Soak up any of the excess solution on the lens surface with fresh paper.
  3. Do not let the lens cleaner air dry! Remove it with a fresh, non-linting lens paper, very gently wiping the remaining lens cleaner from the lens, moving the paper in one direction (left to right, up to down, or the like). Use as much lens paper as needed to do the job.


Clean following the same procedure above in Oculars. Extreme care should be given to cleaning the objectives, and this should only be done by an experienced user. If you are unsure about cleaning objectives, ask Philip Oshel in 024c Brooks Hall.


  1. Clean first with 70% ethanol and a Kim-wipe (not paper towels).
  2. If residue or contamination still remains, use the lens cleaner on a Kim-wipe to further clean the stage.
  3. Care must be taken not to saturate the moving parts of the stage when cleaning!


  1. In general, the body of the microscope shouldn't need to be cleaned.
  2. The scopes are cleaned completely once a year.
  3. If it needs cleaning right away, follow the guidelines for cleaning the stage.

If the image does not improve or if you are unsure about any of the above procedures, please notify Philip Oshel in 024C Brooks Hall or at (989) 774-3576.