Difference between SEM and TEM
Electron microscopes are of two types namely, Scanning electron microscope (SEM) and Transmission electron microscope (TEM). We will further discuss the difference between SEM and TEM.
Table of Contents
Introduction
Before digging deeper into the Difference between SEM and TEM, let us take a look at the introduction. The highly specialised electrostatic and electromagnetic lenses are used in an electron microscope to efficiently control the electron beam and focus it resulting in image formation.
In a Transmission electron microscope (TEM), the electrons are transmitted through an object and then focused by the lenses to form the image.
In a Scanning electron microscope (SEM), the electrons are reflected by the object in a scanned
pattern which are then used to form the image. SEM is becoming remarkably popular with cell
biologists because of its excellent ability to study surface topography, along with improved
resolution (30-100 Å) and its ability to show 3D structure.
Difference between SEM and TEM
difference between SEM and TEM
Discovery
TEM was invented in 1931 by talented German physicist E. Ruska and the electrical engineer M. Knoll .In 1933; Ruska built an electron microscope that exceeded the resolution of an optical microscope. E. F.Burton and students C. Hall, J. Hillier, and A. Prebus1938. at the University of Toronto, constructed the first practical electron microscope. In 1939, Siemens produced the first commercial Transmission Electron Microscope (TEM).
The Scanning Electron Microscope was invented by Manfred von Ardenne in 1937.
What is STEM?
STEM contains special elements of both TEM and SEM. Like SEM, it uses an electron beam that sweeps over the specimen material. The image is formed by the electrons transmitted through the specimen as with a TEM. A STEM is capable of distinguishing specific characteristics of the electron that are transmitted by the specimen, thus deriving information about the specimen not obtainable with a conventional TEM.
Hope the Difference between SEM and TEM is now clear to you.
Also check out, Electron Microscope – YouTube
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