Essential Parts of a Microscope

All of the parts of a microscope must function properly for the microscope to work well.  If one part is substandard, it can render the microscope useless.  The major parts of a microscope are the lenses, the arm, the tube, the illuminator, the stage, and the adjustment knobs.

There are two kinds of lenses on a microscope.  The eyepiece lens, also known as the ocular lens is at the top of the microscope.  This is the part that people look through.  The ocular lens is not adjustable on most models.  The objective lens provides much of the microscope’s magnification.  A microscope usually has a few different objective lenses that vary in strength.  The objective lenses are contained on a circular part placed between the eyepiece and the stage.  Different objective lenses are chosen based on their strength.  When someone wants to use a different strength of objective lens, they turn the circular disk to put another lens over the stage. 

Other than the lenses, the other parts of a microscope are the tube, the arm, the stage, the illuminator and the adjustment knobs.  The tube connects the ocular lens and the objective lens.  People look through the ocular lens and tube and see out of the objective lens at the bottom.  The arm connects the lenses and the stage.  It protrudes to the side and provides a handle to carry the microscope as well. The stage is where the object is placed for examination.  Stage clamps secure the microscope slides to the stage. The microscope slides contain specimens such as blood or other liquids.  The illuminator is below the stage.  This part provides light to make the specimen easier to see.  The illuminator is either an actual light or a mirror. 

Most microscopes feature two adjustment knobs to help focus the lenses.  The coarse adjustment knob is the larger of the two and brings the lens and the stage closer together.  The fine adjustment knob is smaller and is used after the coarse adjustment knob to provide any small adjustments to bring the item into sharp focus.

These parts of a microscope are common to nearly all models.  Some microscopes use slightly different parts.  For example, electron microscopes use electron beams instead of illuminators.