The First Light Microscope and the History of Microscopy

Who Made the First Light Microscope?

There’s no single, certain answer. The compound microscope (one with two or more lenses in a tube) is traditionally credited to the Dutch spectacle makers Hans and Zacharias Janssen, around the 1590s. However, historians treat that claim cautiously, because the evidence for it comes from accounts written decades later.

What is reasonably clear is this. Compound microscopes appeared in the Netherlands and elsewhere in Europe in the early 1600s. They were closely related to the telescope, which emerged in the Netherlands around 1608. By the 1620s, instruments were circulating in London and Rome. Simple magnifying lenses were in use long before that.

The rest of this article sets out the story in order. For an overview of how microscopes work today, see our introduction to microscopy.

Before the Microscope: Lenses and Flea Glasses

People have known for a very long time that a curved piece of glass or crystal can make things look larger. Roman writers, including Seneca, mention that objects seen through a glass globe of water look enlarged.

The big practical step came with spectacles, which appeared in Italy in the late 13th century. Spectacle-making created a trade in lens grinding, and that trade later produced both the telescope and the microscope.

The earliest magnifying instruments were simple tubes with a single lens at one end. They were nicknamed “flea glasses” because people used them to marvel at fleas and other small insects. Their magnification was modest, often around 10x or less.

The Dutch Spectacle Makers and the Janssen Claim

The story usually told is that Hans Janssen and his son Zacharias, spectacle makers in Middelburg, put several lenses in a tube around 1590. They then noticed that nearby objects appeared much larger.

There are good reasons for caution:

• The main sources date from the 1650s, long after the events. They include testimony from Zacharias’s own son, who had an interest in the family’s reputation.
• Zacharias Janssen is thought to have been born around 1585, which would make him a young child in 1590.
• No microscope that can be reliably dated to the 1590s and linked to the Janssens has survived.

Another Middelburg spectacle maker, Hans Lippershey, is sometimes mentioned in the same breath. His well-documented 1608 patent application was for a telescope, not a microscope. Some popular sources mix the two up.

Galileo, Drebbel and the Naming of the Microscope

Galileo Galilei is best known for his telescopes, but he also adapted lens systems to look at small objects. By the mid-1620s he had built a compound microscope that he called an occhiolino (“little eye”).

At around the same time, the Dutch inventor Cornelis Drebbel, who worked in London, was making compound microscopes that attracted attention across Europe.

In 1625, Giovanni Faber, a member of the Accademia dei Lincei in Rome (Galileo was also a member), coined the name “microscope” for the instrument. The same group produced some of the earliest published drawings made with a microscope: detailed studies of bees.

How the First Microscopes Worked

Early compound microscopes used the same basic principle as modern ones. One lens near the object formed an enlarged image, and a second lens near the eye magnified that image further. Our article on how a compound microscope works explains this two-stage idea.

The problem was image quality. Lenses of the time had two big faults:

• Spherical aberration: Light passing through the edge of a lens focused at a slightly different point from light passing through the center, which blurred the image.
• Chromatic aberration: Different colors focused at different points, so images had rainbow fringes.

Adding a second lens multiplied these faults as well as the magnification. Early compound microscopes were therefore usually limited to fairly low useful magnifications.

Hooke and Micrographia

In 1665 the English scientist Robert Hooke published Micrographia, a book of large, detailed engravings of what he saw through his compound microscope: a flea, a louse, the eye of a fly, the point of a needle and much more. It was a popular sensation.

In Micrographia, Hooke described thin slices of cork as being made of tiny boxes. He called them “cells”, which is where the biological term comes from (although he was looking at the empty walls of dead plant cells).

Leeuwenhoek’s Single-Lens Microscopes

Perhaps surprisingly, the most important early discoveries were made with a simple microscope: a single, tiny lens.

Antonie van Leeuwenhoek (1632–1723) was a cloth merchant in Delft. He learned to make very small, highly curved lenses and mounted each one in a small metal plate. The specimen sat on a pin in front of the lens, and the whole device was held up close to the eye. His best surviving instrument magnifies roughly 270 times, far more than typical compound microscopes of his day, and with sharper images.

Starting in the 1670s, Leeuwenhoek sent a long series of letters to the Royal Society in London. He described tiny moving creatures he called “animalcules” in pond water, rainwater and scrapings from teeth. These included protozoa and, in later observations, what appear to have been bacteria. He also described red blood cells and sperm cells. On that last point, sperm cells are easily visible with an ordinary modern compound microscope at around 400x, though looking at them at home is no substitute for a medical semen analysis.

Leeuwenhoek’s work shows why a single lens can be so effective. Our explainer on the principle of the simple microscope covers the optics.

The 1800s: Fixing Color and Blur

For well over a century after Hooke and Leeuwenhoek, the compound microscope improved only slowly. The breakthroughs came in the 19th century:

• Achromatic lenses. Combining two types of glass in one lens greatly reduced color fringing. Achromatic lenses already existed by the 18th century. In 1830, Joseph Jackson Lister published principles for combining lenses that reduced both chromatic and spherical aberration, which helped make good microscope objectives practical.
• Abbe and Zeiss. In Jena, Germany, the physicist Ernst Abbe, working with the instrument maker Carl Zeiss, put objective design on a mathematical footing in the 1870s. Abbe explained how resolution depends on the wavelength of light and the objective’s numerical aperture. This work led to the oil-immersion objective (late 1870s) and, with new optical glasses from Otto Schott, to the highly corrected apochromatic objective (1880s).
• Köhler illumination. In 1893, August Köhler described a method of setting up the light source and condenser to give bright, even illumination. It’s still the standard approach today.

By around 1900, the best light microscopes were approaching the theoretical limit of resolution for visible light, roughly 0.2 micrometers.

Beyond Visible Light: the 20th Century

Since the resolution limit couldn’t be beaten with ordinary light and glass, the 20th century brought new approaches:

• Fluorescence microscopy developed in the early 20th century and became a central tool of biology.
• Phase contrast was invented by Frits Zernike in the 1930s. It made transparent living cells visible without staining, and he received the Nobel Prize in Physics in 1953.
• Confocal microscopy was patented by Marvin Minsky in the late 1950s, and became widely practical decades later with lasers and computers.
• Super-resolution fluorescence techniques found ways around the classic light limit under certain conditions, and were recognized with the Nobel Prize in Chemistry in 2014.

When Was the First Electron Microscope Built?

The first electron microscope was built in 1931 by Ernst Ruska and Max Knoll in Berlin. By 1933 Ruska had built one that could resolve finer detail than a light microscope, and commercial instruments followed by the end of the 1930s. Ruska shared the 1986 Nobel Prize in Physics for this work. See our comparison of light vs electron microscopes for how the two technologies differ.

Timeline at a Glance

The microscope wasn’t invented in a single moment. It developed over centuries, through many lens makers, naturalists and physicists, each solving a problem the previous generation couldn’t.