Light Microscopes Vs Electron Microscopes

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If you are just getting into the world of microscopy, you may be wondering about light and electron microscopes and how they compare to each other.

Light microscopes and electron microscopes are two very different machines.

While you can find the former in thousands of classrooms worldwide, it is rarer to come across an electron microscope.

A few main factors differ one from the other: size, price, technology, ease of use, resolution, and magnification power.

This guide to light microscopes vs electron microscopes will cover what each machine is and where they are used.

Furthermore, we will compare the two and will explain what the similarities and differences are.

Before using either instrument, it is good to know the basics of each and what you will be getting into.

If you are ready to learn more about these fascinating machines, keep on reading.

What Is a Light Microscope

Microscope

A light microscope is an optical instrument that uses light and lenses to magnify an object. Some light microscopes are powered, while others are not.

Unpowered light microscopes use natural light, while powered microscopes use artificial light.

When you first turn a light microscope on, the machine sends the light through a series of lenses and converts it into a tight beam.

The microscope then shines the beam of light on the specimen, either from below or above. An image is created when the light passes through the sample.

Either one or a series of lenses magnify the image and sends it to the eyepiece lens for the user to view.

In order for a light microscope to work properly, the light needs to completely pass through the specimen, meaning that the specimen needs to be very thin.

Furthermore, due to its technology, light microscopes cannot support high-resolution images. However, they can handle a maximum magnification power of around 1000x.

There are a few different kinds of light microscopes, the main two being simple light and compound light microscopes.

A few other models include fluorescence, phase contrast, confocal and ultraviolet microscopes.

History

The first compound light microscope appeared around 1590 when Zacharias Jansen invented the compound microscope with two lenses.

Jansen’s microscope looked nothing like modern microscopes today but was a single collapsing tube.

The instrument appeared to look and function like a telescope but in reverse.

The first compound microscope that Jansen invented had a maximum magnification power of 9x. While these specs do not hold a candle to modern compound microscopes, the technology was impressive for its time.

Around 1670, a man named Antony van Leeuwenhoek invented the simple microscope. Instead of having two lenses, this instrument only had one lens.

However, this model could produce a magnification level of up to 200x and had a much better resolution than the first compound microscope.

Since Leeuwenhoek produced better lenses and thus better microscopes, he was the first one to observe cells such as muscle cells, sperm, protozoans, and bacteria.

Later in the 17th century, Robert Hooke started to refine the light microscope and added some features that you can still see on microscopes today.

One of the first things Hooke added was a stage that would hold the specimen in place. He also added an illuminator as well as a fine and coarse focus knob.

At this point, it was common for microscopes to handle magnification levels of up to 50x. However, the images were still a bit blurry.

This changed when Carl Zeiss and Ernst Abbe further refined the light microscope and added better lenses and a condenser lens.

The addition by Zeiss and Abbe to the instrument was the last major change to light microscopes.

While the microscopes slowly became more and more refined over the years, there were no other massive changes to the structure.

Where Is It Used

You can find light microscopes in many different fields of science, including medicine, mineralogy, microbiology, and material science.

Researchers use light microscopes to study various objects that you can’t see with the naked eye, like bacteria and organelles such as the mitochondria of the cell.

Most of the time, people use light microscopes such as compound microscopes for regular uses such as viewing pollen, mold, insects, plants, or even microorganisms.

Researchers will also use light microscopes when they want to view the original color of a specimen or if they want to view both live and dead specimens.

Typically, you will find light microscopes in many public classrooms and laboratories. These instruments are good to use when you don’t want to train everyone that will be using the instrument.

For instance, many classrooms will have compound microscopes in them. The students will only need a bit of instruction to use these machines.

What Is an Electron Microscope

An electron microscope is a type of microscope that uses electrons to illuminate and scan biological and non-biological specimens.

When it comes to light microscopes, the photon particles that make up light can only produce a certain wavelength.

Electrons can produce much shorter wavelengths than photons, which allows the machine to handle much higher resolutions and magnification powers.

The max magnification power of an electron microscope is 1,000,000x, compared to the 1000x power of a typical light microscope.

There are three main types of electron microscopes, including transmission, scanning, and reflection electron microscopes.

Transmission and scanning electrons are compatible with a variety of different specimens, while scientists mostly use reflection microscopes to study crystals.

It is rarer to find electron microscopes in normal laboratories since these machines are highly specialized and can cost thousands of dollars.

For this reason, researchers only use these microscopes when they have to.

History

During the 1920s, a man named Hans Busch developed the first electromagnetic lens.

According to some sources, he also filed a patent in 1928 for the first-ever electron microscope. However, he did not end up building it.

Shortly after, in 1931, Ernst Ruska (a physicist) and Max Knoll (an electrical engineer) built the first electron microscope.

The first device they built could support a magnification power of 400x. Even though the magnification power was still quite low, the invention showed promise.

In 1933, Ernst Ruska decided to take further steps and refine his creation even more.

A few other men named Bodo von Borries and Helmut Ruska teamed up with Ernst to develop a microscope that could handle higher resolution.

In 1937, the trio built the first-ever scanning electron microscope. One year later, they released the device to the public.

Due to his creation, Ernst Ruska received the Nobel Prize in 1986 in physics. Gerd Binnig and Heinrich Rohrer also earned a portion of the prize due to their contribution to developing the scanning tunneling microscope.

From that point on, the microscope was continually refined until it became the machine it is today. Now, laboratories use electron microscopes for scientific research all over the world.

Where Is It Used

The electron microscope is a very powerful and specialized instrument. The main field of research that scientists use these instruments is the biomedical field.

Scientists use electron microscopes to study the ultrastructures of cells and specimens.

The ultrastructure refers to the structure of biomaterials and cells that you cannot see with light microscopes but only with specialized microscopes.

Researchers use electron microscopes to observe cells, tissues, macromolecular structures, microorganisms, large molecules, crystals, metals, biopsy samples, and organelles.

Since these microscopes can support such a high resolution, scientists can use these instruments to see the internal structures of the specimens listed above.

Comparision

We have now covered light microscopes vs electron microscopes regarding their history, where they are used, and what they are.

This section will examine the debate of light microscopes vs electron microscopes more in-depth and cover the similarities and differences between the two instruments. Let’s get started.

Similarities

Both Machines Form Larger Images of Small Objects

The first and most obvious similarity between the two instruments is that both machines form large images of small objects.

While they may not have the same magnification power, you can take a specimen and study it close-up with both instruments.

Both Require Careful Preparation of Slides to Use Them Properly

Another similarity between light microscopes vs electron microscopes is that you need to prepare the slides carefully.

Each will require different techniques to set the slide up and mount it on or in the machine.

While setting up each slide for the different machines, you will need to handle them with the utmost care since it is easy to disrupt the specimens.

Both Instruments Are Used in Scientific Research

Researchers use both of these instruments to conduct important studies. Fields such as metallurgy, biology, and medical sciences take advantage of these technologies to study various things.

Even though these are two very different microscopes, both have been used to discover important things that have changed the world of science.

Some main discoveries are the atom and the germ theory of disease.

Differences

Both Microscopes Use a Different Illuminating Source

One of the main differences between light microscopes vs electron microscopes is the illuminating source. Light microscopes use light, whether it is powered light or natural light.

On the other hand, electron microscopes use a beam of electrons to illuminate and scan the specimens.

Electron Microscopes Are More Powerful Than Light Microscopes

Another major difference between the two microscopes is that electron microscopes are much more powerful than light microscopes.

While light microscopes have a maximum magnification power of around 1000x, some electron microscopes can handle a power of 1,000,000x.

Light Microscopes Produce Colored Images

If you have ever used an electron microscope before, you may have noticed that the images are black and white. You cannot study specimens in color when it comes to electron microscopes.

However, light microscopes produce colored images, which is an advantage when studying new specimens.

While some institutes colorize electron microscope images, a graphic designer typically takes this job, and the color does not provide any new information about the specimen.

Electron Microscopes Send the Images to a Digital Computer Screen

When you use an electron microscope, you won’t need to look through a lens to see the magnified image.

The microscope will send the image to a digital screen where you can use a mouse and keyboard (or other hardware depending on the machine) to investigate the specimen.

On the other hand, you have to look through the eyepiece lens on a light microscope to see the image. These models do not send images to digital screens like electron microscopes do.

You Can Study Thinner Specimens With Electron Microscopes

When using electron microscopes, the specimen is typically thinner than 0.1 micrometers.

The reason for this is that the electron beam needs to penetrate through the entire specimen to collect the required data.

Since light microscopes have a lower magnification power than electron microscopes, the specimens will typically be thicker than five micrometers.

Conclusion

We hope that this guide to light microscopes vs electron microscopes has helped you learn more about the two instruments.

The light microscope is an optical instrument that uses light to illuminate the specimen and lenses to magnify it.

Users can see the final image through the eyepiece lens.

An electron microscope is a type of microscope that uses a beam of electrons to scan and illuminate the specimen. The microscope then projects the magnified image on a digital screen.

When it comes to light microscopes vs electron microscopes, there are a few similarities.

Both instruments generate magnified images of smaller objects, require careful preparation of slides, and are used in scientific research.

There are also a few major differences as well. Electron microscopes use electrons as an illuminating source, while light microscopes use artificial or natural light.

Furthermore, electron microscopes are more powerful and can magnify much thinner specimens than light microscopes can.

Light microscopes also produce colored images, whereas electron microscopes produce black and white images.

Furthermore, electron microscopes send the magnified images to a digital screen, while light microscopes send the images to the eyepiece lenses.

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