Parts of a Compound Microscope
Eyepiece (Ocular Lens)
- The eyepiece magnifies the image.
- It is the part of the microscope that is looked through.
Objective Lens
- The objective lens magnifies the image.
- Many light microscopes contain multiple objective lenses with different levels of magnification. They are attached to a revolving nosepiece and the different lenses can be selected by rotating the nosepiece.
Coarse Focus Knob
- The coarse focus knob is used for focussing the image over a wide range.
- It is the larger of the two focus knobs.
Fine Focus Knob
- The fine focus knob is used for focussing the image over a narrow range.
- It is the smaller of the two focus knobs.
Stage and Stage Clips
- The stage is the platform where the specimen is placed. The specimen is mounted onto a microscope slide, with a cover slip placed on top of it.
- The stage clips hold the microscope slide in place.
Stage Controls
- The stage controls are knobs that move the stage horizontally, to select the part of the specimen to be viewed.
Lamp
- The lamp is located under the stage and produces the light that passes through the specimen.
- Some microscopes don’t have a lamp but instead have a mirror that reflects light from an external lamp.
Arm
- The arm is the main support of the microscope. When carrying a microscope, always carry it by the arm.

Parts of a compound microscope
(Image: Bezvershenko, Adobe Stock)