If you need to enhance imaging in light microscopy, you will find microscope immersion oil to be ideal for you. This oil is utilized as a vital part of microscope lens systems as it helps in creating a sharper and brighter image compared to other similar designs that have been produced in the absence of immersion oil. Microscope immersion oil works to substitute the air gaps that form between the top and bottom of the slide and the condenser.

The functions

As per Bertrand Courtenay from Rubicon Science, immersion oil gives rise to a couple of features of images that you view with the help of a microscope: brightness and finer resolution. These features tend to be highly critical when you see them under higher magnification. Hence, short focus, the higher power, and some objectives are intended for oil immersion. You will get immersion oil objectives to be available from 40 – 120x. However, you must not confuse them with objectives like “high dry” or water immersion objectives.

The proper method of using immersion oil

Everyone should be conscious of some vital factors before they begin to use immersion oil. The very first thing is people should use only the 100x objective lens for using immersion oil.

You should start the process of focusing your sample utilizing only the 40x objective lens. Additionally, you ought to rotate the objective lens between the 40 and 100x lenses; this way, you will be able to get to your slide’s cover slip.

  • Put one drop of immersion oil right on the top of your cover slip, and the next drop should be dropped on the 100x oil objective lens directly.
  • After this, you should rotate the 100x oil objective lens slowly into place. Then, you should work on clear focus until you get a fine and crisp image.
  • When you finish seeing the 100x oil immersion lens, you ought to make every glass surface clean and oil-free by utilizing a lens cleaning paper.
  • Moisten another piece of lens paper with some alcohol. Alternatively, you can use a lens-cleaning solution for this purpose. This will wipe every glass surface; hence, you will not find any trace of remaining oil on them. If you do not remove the immersion oil, you will see hardened oil on the lenses, and it will affect the clarity of your future.

When should you use the immersion oil?

You should use microscope immersion oil in the following conditions:

  • If you find that your microscope immersion oil has oil, you should use the immersion oil.
  • Immersion oil works best to view samples that do not move or are dead. People also use this oil when they want to see tiny moving protists; however, in this process, the finest specimens refuse to move.
  • You can use immersion oil when you want to see details of striations or bacteria strands.
  • Everyone uses this oil when they want to see images clearly.


Using microscope immersion oil seems to be beneficial when you want to augment your resolution. This way, you can see images brightly. However, you should be conscious of its benefits and the ideal time when you should use it.