The microscope is a laboratory optical instrument that in its most basic definition is used to give a magnified view of whatever small object is placed in its view.
They are an incredibly useful and important scientific instrument that has been massively important in the discovery of many scientific findings and is a tool that continues to be used today.
Microscopes are so effective that they allow the user to be able to see details on an object that are not able to be seen by the naked eye.
This detail has made it possible to see things like the cellular structure of different organisms and gives us a much better understanding of the scientific world.
While the microscopes of today seem incredibly well-designed for their purpose and are incredibly efficient in their use and construction, they have not always been this way.
The first reference to microscopes could be as early as Roman philosophers, but the first actual evidence we have of microscopes is from the 1300s.
There is of course a large difference between the microscopes of the late 1300s and the microscopes of today.
However, the microscopes of this era are of course important in understanding why microscopes are how they are today and what has influenced their design.
So let’s have a look at what the history of the microscope is to see how it got to what they are today and see who we can credit as the inventor of the microscope.
What Is The Earliest Microscope?
As previously mentioned, there were mentions as far back of Roman philosophers using burning glasses, popularly believed to mean is using specifically shaped glass to converge the sun’s rays to create a more concentrated ray of the sun’s light.
However, it was not until the 1300s that glass was shaped into a magnifying shape used in spectacles and for magnifying glasses. This process was known as grinding glass.
Of course, this was very primitive technology and not that attached to microscopes, but using glass to magnify is definitely one of the first steps in the process of reaching a microscope.
It was not until late into the 16th century that Dutch lens makers were able to design specific lenses for magnifying objects.
However, the now incredibly famous astronomer Galileo Galilei was credited for designing the first device known as a microscope in 1609.
However, there are Dutch spectacle makers from a similar era called Zaccharias Janssen and Hans Lipperhey that are recognized as the first people to develop and design the concept of the compound microscope.
The compound microscope is made by placing different types of lenses of different sizes on the opposite ends of a tube at a set distance apart.
It was discovered during this era that this combination of lenses will give a much greater degree of magnification.
The Discoveries Of Anton Van Leeuwonhoek
Later in the century, a scientist called Anton van Leeuwenhoek started polishing and grinding lenses himself which led to him discovering that if you shape a lens in a particular way this has the possibility to enlarge the view of an image.
He went on to create and lead the way for the creation of lenses of a higher quality for microscopes.
He is specifically important for his work because his lenses in particular were the first in recorded history to be able to see the tiny details of organisms like bacteria putting certain organisms under the classification of ‘microscopic’.
This discovery lead to Leeuwenhoek historically being seen as the founder of microscopy (being the field of using microscopes for viewing objects not being able to be seen by the naked eye) and eventually leading to the development of, most importantly, cell theory.
The Development Of The Achromatic Lens
The microscopes discovered and pioneered by Leeuwonhoek were used for over a century until there were more major discoveries made to improve microscopy.
The earlier microscopes, while revolutionary, were quite hard to use. One of the biggest problems was how often light refracted through the lenses which would actually affect and alter the appearance of the image being magnified.
This made it difficult to get accurate images from early microscopes.
This problem was not overlooked, however, and it eventually led to the creation of the achromatic lens which was originally used for eyeglasses.
The lens was developed by Chester Moore Hall in 1729 and this was the first big change in microscopes to massively improve quality since Leeuwonhoek.
These lenses improved the accuracy of the microscope by limiting the aforementioned light refraction by correcting the shaping of the lenses in coordination with each other.
This development did not just improve the quality of microscopes but also improved telescopes as well as eyeglasses.
Mechanical Improvements For Microscopes
Since Moore Hall’s discovery and creation of the achromatic lens, there were not too many major changes for the lenses themselves throughout the 18th and 19th centuries.
However, this era was when there were many changes in the housing for the lenses as well as big changes in the design and quality of microscopes.
When it comes to developments for devices like this, it is understandable that the device will become smaller and more compact and this happened throughout this era.
Generally speaking, the quality of the devices became more stable, and minor lens improvements got rid of many optical issues which were common with earlier iterations of the instrument.
This era also makes the history of the microscope a lot less linear. The world was beginning to become a lot more global with more international connections.
This meant that creations like the microscope were now all over the world and different countries were improving the device in their own unique ways to change it. Examples of this include:
- August Kohler is the credited inventor of giving microscopes uniform illumination making viewing microscopic specimens significantly easier.
- Ernst Leitz was credited as the inventor of switching out the different magnifications on the same single device.
- He did this by putting different changeable lenses on each device and what is described as a moveable turret at the end of the lens tube.
- Ernst Abbe is credited for designing a microscope that was made to make more colors of the light-spectrum visible. This design eventually provided the tools for more modern scientist Zeiss to be able to create an ultraviolet microscope.
Understanding the history of microscopy is paramount in understanding the history of modern science.
The best example of this was that until microscopy, the causes of illnesses and diseased were completely unknown and based on guesswork. That is of course until microscopy made it possible to view microorganisms.
A scientist known as Charles Spencer was the pioneer of proving that light changes how images are seen, and it took a gradual development of over 100 years to make a microscope useable without light.
In the 1930s the first electron microscope was made by Max Knoll and Ernst Ruska, these microscopes made viewing the smallest particles possible but are unusable on living objects.
The scanning tunneling microscope was made in 1981 by Gerd Bennig and Heinrich Rohrer allowing viewings at the atomic level. This was improved upon by Bennig in 1986 through the invention of the atomic force microscope.
So as you can see, from roman philosophers burning-glass to Leeuwonhoek, to Bennig, the design of microscopes has massively changed over the years.