Annular dark-field imaging

Annular dark-field imaging

Annular dark-field imaging is a method of mapping samples in a scanning transmission electron microscope (STEM). These images are formed by collecting scattered electrons with an annular dark-field detector in scanning transmission electron microscopes.

For dark field imaging, the annular dark field detector collects a much larger number of electrons than conventional dark field imaging in the TEM. This gives advantages in terms of signal collection efficiency and lower electron dose required.

An annular dark field image formed only by very high angle, incoherently scattered electrons - as opposed to Bragg scattered electrons - is highly sensitive to variations in the atomic number of atoms in the sample (Z-contrast images). This technique is also known as High Angle ADF (HAADF).


Wikimedia Foundation. 2010.

Игры ⚽ Нужен реферат?

Look at other dictionaries:

  • Dark field microscopy — (dark ground microscopy) describes microscopy methods, in both light and electron microscopy, which exclude the unscattered beam from the image. As a result, the field around the specimen (i.e. where there is no specimen to scatter the beam) is… …   Wikipedia

  • Transmission electron microscopy — A TEM image of the polio virus. The polio virus is 30 nm in size.[1] 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… …   Wikipedia

  • Electron microscope — Diagram of a transmission electron microscope A 197 …   Wikipedia

  • Scanning transmission electron microscopy — A scanning transmission electron microscope (STEM) is a type of transmission electron microscope. With it, the electrons pass through the specimen, but, as in scanning electron microscopy, the electron optics focus the beam into a narrow spot… …   Wikipedia

  • List of materials analysis methods — List of materials analysis methods: Contents: Top · 0–9 · A B C D E F G H I J K L M N O P Q R S T U V W X Y Z μSR see Muon spin spectroscopy …   Wikipedia

  • Royal Medal — Die Royal Medal, auch The Queen s Medal genannt, ist eine von der Royal Society verliehene Auszeichnung für Wissenschaftler, die innerhalb des Commonwealth of Nations besonders wichtige Beiträge zur Weiterentwicklung der Wissenschaften geleistet… …   Deutsch Wikipedia

  • Queen's Medal — Die Royal Medal, auch The Queen s Medal genannt, ist eine von der Royal Society verliehene Auszeichnung für Wissenschaftler, die innerhalb des Commonwealth of Nations besonders wichtige Beiträge zur Weiterentwicklung der Wissenschaften geleistet… …   Deutsch Wikipedia

  • Ondrej Krivanek — Ondrej L. Krivanek FRS (born August 1, 1950, as Ondřej Ladislav Křivánek) is a Czech/British physicist resident in the United States, and a leading developer of electron optical instrumentation. He was born in Prague, and graduated from a… …   Wikipedia

  • Phase contrast microscopy — Phase contrast image of a cheek epithelial cell Phase contrast microscopy is an optical microscopy illumination technique of great importance to biologists in which small (invisible to the human eye) phase shifts in the light passing through a… …   Wikipedia

  • microscope — /muy kreuh skohp /, n. 1. an optical instrument having a magnifying lens or a combination of lenses for inspecting objects too small to be seen or too small to be seen distinctly and in detail by the unaided eye. 2. (cap.) Astron. the… …   Universalium

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”