Microscopy

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Microscopes were invented in the 16th century. The lenses of these microscopes were not very good, so the images were not clear. The first microscopes had only one lens. They were called simple microscopes.

It was not until 1590 that two Dutch spectacle makers, Hans and Zacharias Janssen, made a microscope with two lenses. We call this kind a compound microscope.

Later, and English scientist called Robert Hooke built a compound microscope. He used it to look at things that were too small to see with the naked eye. In 1665, he published the first book of drawings of these microscopic structures. One of the drawings was a slice of cork.

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We use microscopes to magnify very small things. It is better to use a hand lens to look at larger things. For example, you could look at the leg of a bee using a microscope, but you would use a hand lens to look at a whole bee.

Light passes through the microscope in this order:

Diaphragm or disc

Object being looked at

Object lens

Eyepiece lens