Elegant constrictions in a cellular kill switch

The inner workings of a "self-destruct switch" present on human cells that can be activated during an immune response have been revealed. In unprecedented detail, KAUST scientists with collaborators in China report the 3D ...

Aluminum alloy research could benefit manned space missions

The MIAMI-2—Microscopes and Ion Accelerators for Materials Investigations—facility has helped Dr. Matheus Tunes investigate a new alloy that will harden aluminum without increasing its weight significantly.

Looking inside the glass

A team of researchers from the Institute of Industrial Science at The University of Tokyo used advanced electron spectroscopy and computer simulations to better understand the internal atomic structure of aluminosilicate ...

Researchers demonstrate attosecond boost for electron microscopy

A team of physicists from the University of Konstanz and Ludwig-Maximilians-Universität München in Germany have achieved attosecond time resolution in a transmission electron microscope by combining it with a continuous-wave ...

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Transmission electron microscopy

Transmission electron microscopy (TEM) is a microscopy technique whereby a beam of electrons is transmitted through an ultra thin specimen, interacting with the specimen as it passes through. An image is formed from the interaction of the electrons transmitted through the specimen; the image is magnified and focused onto an imaging device, such as a fluorescent screen, on a layer of photographic film, or to be detected by a sensor such as a CCD camera.

TEMs are capable of imaging at a significantly higher resolution than light microscopes, owing to the small de Broglie wavelength of electrons. This enables the instrument to be able to examine fine detail—even as small as a single column of atoms, which is tens of thousands times smaller than the smallest resolvable object in a light microscope. TEM forms a major analysis method in a range of scientific fields, in both physical and biological sciences. TEMs find application in cancer research, virology, materials science as well as pollution and semiconductor research.

At smaller magnifications TEM image contrast is due to absorption of electrons in the material, due to the thickness and composition of the material. At higher magnifications complex wave interactions modulate the intensity of the image, requiring expert analysis of observed images. Alternate modes of use allow for the TEM to observe modulations in chemical identity, crystal orientation, electronic structure and sample induced electron phase shift as well as the regular absorption based imaging.

The first TEM was built by Max Knoll and Ernst Ruska in 1931, with this group developing the first TEM with resolving power greater than that of light in 1933 and the first commercial TEM in 1939.

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