Magnification

• Microscopes produce images that are much larger than the actual size of the objects being viewed.

• The magnification of a microscope is a measure of how much bigger the image is than the real object.

• For example, if a microscope has a magnification of ×100, the image produced is 100 times larger than the actual object.

• The different types of microscopes have different levels of magnification.

• Stereo microscopes have a maximum magnification of ×100.

• Compound microscopes have a maximum magnification of ×1000.

• Scanning electron microscopes have a maximum magnification of about ×100,000.

• Transmission electron microscopes have a maximum magnification of about ×1,000,000.

Microscopes produce images that are much larger than the real size of objects.

(Image: OpenClipart-Vectors, Pixabay)

Calculating Total Magnification

• Light microscopes (compound microscopes and stereo microscopes) contain two magnifying lenses – the ocular lens (eyepiece) and the objective lens.

• The total magnification of a light microscope is the product of the magnification of each lens – in other words, it is calculated by multiplying the magnification of the two lenses.

• For example, if an ocular lens has a magnification of ×10 and an objective lens has a magnification of ×40, the total magnification of the microscope is ×(10 × 40) = ×400.

• Stereo microscopes usually have a total magnification of ×100 because the ocular lens has a magnification of ×10 and the objective lens has a magnification of ×10.

• Compound microscopes have different levels of magnification, depending on the magnification of each objective lens.

• Most compound microscopes have three objective lenses – ×4, ×10 and ×40, with more expensive microscopes having a fourth ×100 lens.

• Like stereo microscopes, the ocular lens on compound microscopes has a magnification of ×10.

• Therefore, compound microscopes have total magnifications of ×40, ×100, ×400 or ×1000, depending on which objective lens is being used.

Common magnifications of light microscopes