Diffraction Abbreviations

The etymology of diffraction refers us to diffractus, a term that can be translated as “broken”. This concept is used in the field of physics to name the deflection of a wave when it crosses an opening or hits the edge of an opaque element.

Diffraction is a phenomenon that involves all waves: electromagnetic, radio, sound, etc., and its development can be predicted using different mathematical approaches. When the wave crosses a crack or hits an obstacle, it is deflected.

There is an analysis method called Huygens’ principle, which allows us to understand diffraction as a wave front that can be seen as a series of emitters capable of redirecting the wave when it oscillates and thus promoting its propagation. Although the waves produced by the oscillators are spherical, their interference causes a plane wave that moves in the same direction as the initial one.

Near – field diffraction, also known as Fresnel diffraction (after Augustin-Jean Fresnel, a French physicist born in 1788 and died in 1827), is a diffraction pattern of those electromagnetic waves that are obtained in the vicinity of the element that causes the phenomenon itself, which is usually an opening or a source.

In the field of optics, the branch of physics that is dedicated to studying the properties and behavior of light, it is known by the name of opening to a perforation or hole through which light passes. Said in more specific terms, it is the determining factor of the angle that the cone of the beam of rays will have that will be focused in the plane.

Another of the concepts that are key to understanding and calculating near field diffraction is the Fresnel number, another of the contributions of the respected French physicist. It is a number that is not defined by physical units (that is, a dimensionless or pure number ), used in the field of optics and defined by the following equation: Aperture squared / Distance between the aperture and the screen x wavelength.

The one of the far field or of Fraunhofer, on the other hand, is oriented to a wave whose source and its screen are very far from the obstacle that causes the diffraction, so that plane waves (also called one- dimensional waves, are constant and their wavefronts are parallel and normal to the phase velocity).

It is correct to say that far field diffraction is a special case of the previous one. Its analysis is easier, since the distance between the aperture and the screen is considerable and it is possible to study the rays in parallel, something that does not happen with near-field diffraction.

Thanks to the use of the Fresnel number, it is possible to know which of the two types of diffraction we are dealing with: when its value is much less than unity, the present phenomenon is the diffraction of the far field, and vice versa.

The phenomenon of diffraction is applied in different types of studies and research. The so-called X-ray crystallography is based on diffraction to analyze materials with a periodic structure, such as crystals. This technique proved very important in the study of the structure of DNA, for example.

In this case, the X-rays undergo diffraction due to the electrons that are surrounding the atoms of the crystal. The beam that emerges from this encounter contains data about the types of atoms and their positions. This information is observed and measured through different detectors.

List of Acronyms Related to Diffraction

Acronym Meaning
AED Auger Electron Diffraction
APD Azimuthal Photoelectron Diffraction
BDW Boundary Diffraction Wave
CDI Coherent Diffraction Imaging
CXD Coherent X-ray Diffraction
CMRTD Combined Method of Ray Tracing and Diffraction
CBED Convergent-Beam Electron Diffraction
DAFS Diffraction Anomalous Fine Structure
DEI Diffraction Enhanced Imaging
DL Diffraction Limited
DPI Diffraction Products Inc.
DDM Discrete Diffraction Manifold
EBSD Electron Backscatter Diffraction
ED Electron Diffraction
FSDP First Sharp Diffraction Peak
FWD Floquet Wave Diffraction
GTRD Generalized Transverse Resonance-Diffraction
GOD Geometrical Optics and Diffraction
GTD Geometrical Theory of Diffraction
GDT Geophysical Diffraction Tomography
GIAXRD Grazing Incidence Angle X-Ray Diffraction
GID Grazing Incidence Diffraction
HEED High Energy Electron Diffraction
HXRXD High Resolution X-Ray Diffraction
ITD Incremental Theory of Diffraction
KED Knife-Edge Diffraction
LACBED Large-Angle Convergent-Beam Electron Diffraction
LDPA Laser Diffraction Particle Analyzer
LEED Low Energy Electron Diffraction
LODE Low- order Edge Diffraction
LHDC Luebbers’ Heuristic Diffraction Coefficient
MBD Micro-Beam Electron Diffraction
MAD Multiwavelength Anomalous Diffraction
NHDC New Heuristic Diffraction Coefficient
NPD Normal Photoelectron Diffraction
OGD Obstacle Gain Diffraction
ODR Optical Diffraction Radiation
PD Photoelectron Diffraction
PTD Physical Theory of Diffraction
PDS Pittsburgh Diffraction Society
PDF Powder Diffraction File
PXRD Powder X-Ray Diffraction
PDMEE Primary-Beam Diffraction Modulated Electron Emission
QDE Quasi-Optic Diffraction Element
RHEED Reflected High Energy Electron Diffraction
REDUNDANT Reflection Electron Diffraction
RED Reflection Electron Diffraction
SAD Selected Area Diffraction
SAED Selected Area Electron Diffraction
SCDES Single Crystal Diffraction
SCD Single Crystal Diffraction
SAD Small Angle Diffraction
SRXRD Spatially Resolved X-Ray Diffraction
DOCTOR Spectral Theory of Diffraction
STD Spectral Theory of Diffraction
SPALEED Spot Profile Analysis Low Energy Electron Diffraction
SED Strip Endpoint Diffraction
SID Strip Interior Diffraction
SDPD Structure Determination from Powder Diffraction
TOFD Time of Flight Diffraction
TXD Transient X-Ray Diffraction
TED Transmission Electron Diffraction
THEED Transmission High-Energy Electron Diffraction
TSED Transmission Scanning Electron Diffraction
TRD Transverse Resonance Diffraction
UATD Uniform Asymptotic Theory of Diffraction
UGTD Uniform Geometrical Theory of Diffraction
UNITED Uniform Geometrical Theory of Diffraction
UTD Uniform Geometrical Theory of Diffraction
UNITED Uniform Theory of Diffraction
UTD Uniform Theory of Diffraction
WAXD Wide-Angle X-Ray Diffraction
XRD X-Ray Diffraction
DRX X-Ray Diffraction
XRDA X-Ray Diffraction Analysis
XPD X-Ray Photoelectron Diffraction