The following are five surprising facts about scanning and transmission electron microscopy.

Estimated read time 6 min read

Microscopy and electron microscopy are useful tools for obtaining high-resolution images. Ideas result from the interaction of electron beams with the sample. As a focused stream of electrons accelerates towards the specimen in a vacuum, an electron microscope works. The process is similar to how optical microscopes capture images using light.

The wavelength of light limits the maximum magnification possible with optical microscopes, which are wonderful tools for magnifying things for examinations. A microscope using electrons has a higher magnification than a microscope using light. The higher magnification is due to electrons having smaller wavelengths than light. By contrast, optical microscopes can see thousands of times smaller than what an electron microscope can see.

Is it Possible to Use an Electron Microscope in the Early Years of Research?

The electron microscope reveals the outline of objects by moving electrons across them. This outline converts into visible light to be examined by scientists. If you wonder how much is an electron microscope cost? According to statistics, a new electron microscope can cost anywhere between $80,000 and $10,000,000, but the average price is $294,000. Configured, customized, and with high-end components, an electron microscope can cost between $80,000 and $10,000,000.

An Introduction to Electron Microscopes

There are four kinds of environmental scanning electron microscopes. These microscopes all serve different purposes. Perhaps it will surprise you that these devices are useful for so many other things.

TEM stands for transmission electron microscope

An electron beam travels toward an object you wish to examine when using a Transmission Electron Microscope (TEM). While some of these electrons reflect off of the thing, others pass through. Bypassing an electron through the object, you’re able to get a magnified image of the sample that’s five million times larger than what it is in real life.

The Reflection Electron Microscope (REM) focuses on reflections.

Similar to Transmission Electron Microscopes, Reflexion Electron Microscopes work by returning electrons to their source. In contrast to REMs (and you may have guessed this already), REMs provide an image of your specimen based on electrons reflected in the camera. If you need to carefully examine an object’s surface, reflection electron microscopes may be the tool you need.

SEM stands for Scanning Electron Microscope

An SEM works differently than a light microscope in that it passes a narrow beam of electrons over the object under examination slowly. Bypassing a beam of electrons over your specimen, you will gradually see an image magnified based on how they reflect or absorb.

STEM stands for Scanning Transmission Electron Microscope

Scanning and transmission electron microscopy combine a high TEM with the incredibly detailed surface of an SEM. The STEM allows scientists to conduct complex analyses of a specimen, which are more challenging to operate with a Transmission Electron Microscope.

It is never advisable to combine TEM and SEM images

Electron microscopes can typically fall into two categories: scanning electron microscopes (SEM) and transmission electron microscopes (TEM). TEM and SEM work differently in the way images are captured and in how the images are processed.

Can you tell the difference between SEM and TEM images below? The process of understanding the differences between these two types of electron microscopes isn’t complicated once you know what they are.

SEM – what is it?

Scanning Electron Microscopy is also known as SEM. In an SEM, an electron beam focuses on a single direction to scan the sample’s surface. Images of SEM images can easily reveal a sampling’s surface topography. Therefore it is possible to interpret them in 3-D.

What is the working principle of a scanning electron microscope?

High-energy electrons are emitted from an electron source (an electron gun) toward a sample to create a high-resolution image, the main scanning electron microscope principle. Electromagnetic lenses help to focus the electron beam. As the focused stream reaches the piece, it scans the surface with its electromagnetic field. When electrons interact with the sample, they become secondary electrons, backscattered electrons, and X-rays. Images emerge from the interactions between electrons and representatives.

Is TEM a type of technology?

Microscopes used in transmission electron microscopy are called TEMs. When using a TEM, you get an image of the sample’s internal structure by shining a beam of electrons on it. Image-making takes place through the transmission of electrons from a selection. An example must be incredibly thin for electrons to pass through thin pieces, often as lean as 150 nm. That’s why TEM takes pictures in two dimensions. 

An electron transmission microscope, what does it do?

A thin sample travels through an electron source as it is ionized. Electrons are then detected after the pieces have passed through the detector. It is possible to use either CCD cameras or fluorescent screens as detectors.

Comparison of SEM and TEM

Biological, physical, and chemical sciences benefit from the use of SEM and TEM. There is a major difference between SEM and TEM, and that is that SEM visualizes the surface topography of the specimen. At the same time, the latter sees through to the interior of the thin sample. While SEM can magnify an image 2,000,000 times, it requires a lot of energy to do so. Tens to hundreds of millions of times are possible using TEMs.

Use, Care, and Maintenance of a Microscope

Do we see colors when looking through an electron microscope?

No, that’s not true.

The color is a property of light (or photons), and scanning electron microscope resolution brings an image of a specimen through an electron beam. Therefore no color information is captured. Samples with electrons passing through them appear white, while pieces without electrons appear black.

An electron microscope produces an image that looks like a “contrast” or pattern. This process has black and white photos.

Right on the right, you can see that the color of the electron microscope photography came afterward.

Images taken with an electron microscope that is not real

Images such as the virus images on the left below, which we often found on Pinterest, are very cool. Does it appear that the pictures take place with an electron microscope?

No, that’s not true.

Computer simulation is most likely what you can see below to the left. A typical electron microscope lacks a depth of field on this scale, and the model has perspective distortion, suggesting the “lens” would be in an unusual location.

Here is the real image from a transmission electron microscope taken on the right of the screen. Here is a pictorial representation of the scale bar (100 nm) at a 150,000x magnification. Also shown are black-and-white electron micrographs. Therefore, the right image represents what is seen by an electron microscope.

Wrong organisms identified by electron microscope images

Some websites claim that the imagery below is a picture of “Chalk under an electron microscope.”

As you can see, this is not the look of chalk. Here is an image of a cell of an organism called a Coccolithophore that accumulates calcium carbonate shells called “coccoliths” to create chalk.

A picture taken through an electron microscope would not be acceptable

The image below is an example of one you might have seen. There is an assumption that it is an electron microscope image, but in reality, it isn’t. A technique called confocal photography makes the image.

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