How to Compare TEM & SEM

The use of electron microscopes allow study of examination of much smaller particles.
••• blue particles image by Christopher Ursitti from Fotolia.com

Transmission electron microscope (TEM) and scanning electron microscope (SEM) are microscopic methods for viewing extremely small specimens. TEM and SEM can be compared in specimen preparation methods and applications of each technology.

TEM

Both types of electron microscopes bombard the specimen with electrons. The TEM is suitable for studying the inside of objects. Staining provides contrast and the cutting provides ultra thin specimens for examination. TEM is well-suited for examination of viruses, cells and tissues.

SEM

Specimens examined by SEM require a conductive coating such as gold-palladium, carbon or platinum to collect excess electrons that would obscure the image. SEM is well-suited to view the surface of objects such as macromolecular aggregates and tissues.

TEM Process

An electron gun produces a stream of electrons that are focused by a condenser lens. The condensed beam and transmitted electrons are focused by an objective lens into an image on a phosphor image screen. Darker areas of image indicate that less electrons were transmitted and that those areas are thicker.

SEM Process

As with the TEM, an electron beam is produced and condensed by a lens. This is a course lens on the SEM. A second lens forms the electrons into a tight, thin beam. A set of coils scans the beam in a similar manner to television. A third lens directs the beam into the desired section of the specimen. The beam can dwell upon a specified point. The beam can scan the entire specimen 30 times per second.

Related Articles

What Are the Advantages of the Transmission Electron...
How Does a Microscope Magnify Objects?
What Are the Different Types of Microscopy Used in...
Different Kinds of Microscopes & Their Uses
Types of Microscopes Used in Biology
Kinds of Microscopes & How They Are Used
What Is the Function of a Microscope?
The Advantages of Studying Cells Under a Light Microscope
Why Are Electron Microscopes Important?
What is the Difference Between a Magnifying Glass and...
The Comparison of a Light Microscope to an Electron...
How Is a Sample Prepared for Viewing Under a Microscope?
The Focal Length of Microscope Objectives
Various Types of Microscopes in Biology
Electron Microscope Advantages
What Are the Uses of a Converging Lens?
What Is the Resolution of a Microscope?
Differences Between a Simple & Compound Microscope
How Do Bright Light Microscopes Work?

Dont Go!

We Have More Great Sciencing Articles!