QVprep Biology Lessons

Light Microscope



Compound microscope: The common light microscope used in the laboratory is called a compound microscope because it contains two types of lenses that function to magnify an object.

Ocular lens and objective lens: The lens closest to the eye is called the ocular lens and the lens closest to the object is called the objective lens.

Condenser: Most microscopes have an apparatus called a condenser in the base, which condenses light rays to a strong beam.

Diaphragm: A diaphragm located on the condenser controls the amount of light coming through it.

Magnification of an Object: To magnify an object: a) Light is projected through an opening in the stage b) It hits the object and then enters the objective c) An image is created d) This image becomes an object for the ocular lens, which remagnifies the image.

Total magnification possible with the microscope: Thus, the total magnification possible with the microscope is the magnification achieved by the objective multiplied by the magnification achieved by the ocular lens.