History of Microscopes

A microscope is an instrument used for viewing objects that are too small to be seen easily by the naked eye. There are many types of microscopes, from the common optical microscope—which uses light to magnify a sample—to the electron microscope, ultramicroscope, and various types of scanning probe microscopes.

No matter what kind of microscope you're using, it had to start somewhere. Understand the history of this invention with this microscope timeline.

Early Years

• Circa 1000 CE: The first vision aid, called a "reading stone," was created (inventor unknown). It was a glass sphere that magnified reading materials when laid on top of them.
• Circa 1284: Italian inventor Salvino D'Armate is credited with inventing the first wearable eyeglasses.
• 1590: Two Dutch eyeglass makers, Zacharias Janssen and son Hans Janssen, experimented with multiple lenses placed in a tube. The Janssens observed that objects viewed in front of the tube appeared greatly enlarged, creating both the telescope and the forerunner of the compound microscope.
• 1665: English physicist Robert Hooke looked at a sliver of cork through a microscope lens and noticed "pores" or "cells" in it.
• 1674: Anton van Leeuwenhoek built a simple microscope with only one lens to examine blood, yeast, insects, and many other tiny objects. He was the first person to describe bacteria, and he also invented new methods for grinding and polishing microscope lenses. These techniques allowed for curvatures providing magnifications of up to 270 diameters, the best available lenses at that time.

1800s

• 1830: Joseph Jackson Lister reduced spherical aberration (or the "chromatic effect") by showing that several weak lenses used together at certain distances provided good magnification without blurring the image. This was the prototype for the compound microscope.
• 1872: Ernst Abbe, then research director of the Zeiss Optical Works, wrote a mathematical formula called the "Abbe Sine Condition." His formula provided calculations that allowed for the maximum possible resolution in microscopes.

1900s

• 1903: Richard Zsigmondy developed the ultramicroscope capable of studying objects below the wavelength of light. For this, he won the Nobel Prize in Chemistry in 1925.
• 1932: Frits Zernike invented the phase-contrast microscope that allowed for the study of colorless and transparent biological materials. He won the 1953 Nobel Prize in Physics for it.
• 1931: Ernst Ruska co-invented the electron microscope, for which he won the Nobel Prize in Physics in 1986. An electron microscope depends on electrons rather than light to view an object. Electrons are sped up in a vacuum until their wavelength is extremely short—only 0.00001 that of white light. Electron microscopes make it possible to view objects as small as the diameter of an atom.
• 1981: Gerd Binnig and Heinrich Rohrer invented the scanning tunneling microscope that gives three-dimensional images of objects down to the atomic level. They won the Nobel Prize in Physics in 1986 for this accomplishment. The powerful scanning tunneling microscope is one of the strongest microscopes to date.