List the optical parts of the microscope

Eyepiece lens: the lens at the top that you look through. They are usually 10X OR15X  

Tube: connects the eyepiece to the objective lenses  

Arm : supports the tube and connects it to the base  

Base : the bottom of the microscope, used for supports  

Illuminator: a steady light source used in place of a mirror. If your microscope has a mirror, it is used to reflect light from an external light source up through the bottom of the stage.

Stage: the flat platform where you place your slides. Stage clips hold the slides in place. If your microscope has a mechanical stage, you will be able to move the slide around by turning two knob one moves it left and right ,the other moves it up and down.

Revolving: this is the parts that holds two or more objective lenses and can rotated

To easily to change power.

And there are so many objective  

Objective lense  

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