Centre Optical Instrumentation Laboratory

Cleaning Objectives

General Cleaning after use
1. If there is any biological material (ie cell culture medium) or unidentified material, wipe with lens tissue dipped in distilled water. Using water first prevents the ethanol fixing the material to the objective
2. Gently wipe the surface of the lens with a lense tissue dipped in 70% ethanol
3. Dry the excess ethanol using a fresh lens tissue
Note. Its a good idea to wipe the lens using a dry lens tissue and applying fresh immersion oil when changing between slides. This prevents oil accumultion running down the sides of the objective which is harmful to the objective and the microscope itself.
Full Cleaning
1. Unscrew the objective from the microscope being careful not to drop it.
2. View the front element of the objective under a stereo microscope
3. Put a few drops of ethanol onto the objective and gently wipe away the dirt, in extreme cases use chloroform as the solvent for the dirt and Q tips to gently remove dirt.
4. When using Q tips use very light pressure to avoid damaging the lens.