AZtec Tru-I, the EBSD indexing engine, ensures that users collect the best quality patterns and can solve them accurately, reliably and automatically. Pattern collection and solving are performed in real-time.

In this section:


Collect the high quality patterns which are essential to obtaining accurate EBSD data.

  • AZtec has an optimised system design, for the collection of excellent patterns, even at high speeds or high binning
    • The signal strength and noise are quantified and can be used as a measure of pattern quality

Dynamic background correction enables pattern by pattern contrast optimisation.

  • Excellent quality patterns can be achieved from all materials
    •  includes multiphase materials, where the phases can have significantly different atomic numbers
  • Dynamic background correction automatically masks screen imperfections

EBSD analysis and Tru-I Indexing Engine



Intelligent band detection

AZtec implements an intelligent band detection routine that determines which of the detected bands should be used in the indexing.

  • Intelligent band detection uses both the average intensity of the band and its position in the area of interest
  • Improves the percentage of correctly indexed points, especially for materials exhibiting indistinct bands or where pattern quality is low

Magnetic Field Correction solves distorted patterns

In some applications, high magnetic fields from the SEM lenses distort the electron backscattered diffraction patterns. This distortion curves the Kikuchi bands and shifts the pattern centre, but can be corrected automatically using AZtec.

  • The correction straightens the bands and corrects the pattern centre so patterns can be correctly solved
  • A dipole correction described in Oxford Instruments’ US patent 7442930B2 is applied

EBSD Magnetic Field Correction

Class Indexing

The EBSD indexing routine is critical in achieving accurate results - AZtec uses a new method, Class Indexing.

  • This method is robust and the correct solution can be achieved even if one or more detected band is not included in the list of reference reflectors
  • The system is less sensitive to the operator selecting the number of bands and reflectors

EBSD and Class Indexing

Distinguish similar crystal structures

AZtec correctly indentifies phases with similar crystal structures by comparing band width.

EBSD software and Tru-I Indexing

Refined Accuracy Algorithm

A new and innovative ‘Refined Accuracy Algorithm*’extends traditional EBSD analysis to deliver unrivalled accuracy and level of detail...

  • Refines the position of the Kikuchi bands after indexing so the most accurate orientation measurements are achieved
  • Overcomes the well-documented limitations of the Hough transform
  • The Ni patterns (below) illustrate the optimisation benefits:
    • Pattern A shows the initial band detection based on Hough
    • Pattern B shows the band position after refinement by the new method

* patent pending

Refined Accuracy EBSD

AZtec Refined Accuracy delivers:

  • Class leading orientation measurement accuracy real-time
    • enhances boundary characterisation
    • identifies subtle subgrain microstructures
    • optimises fit between acquired pattern and solution