NPAR™

Neighbor Pattern Averaging & Reindexing (NPAR™) is an innovative approach to measuring crystallographic orientation from Electron Backscatter Diffraction (EBSD) patterns. Band detection performance depends on the signal to noise ratio (SNR) within the EBSD pattern. Noise and decreased SNR can be introduced into patterns through the use of camera gain to amplify the signal in order to obtain faster camera frame rates. Band detection becomes unreliable and indexing performance suffers when the noise exceeds allowable limits. Noise levels can be lowered by reducing the gain on the detector and also by averaging multiple frames together, however both of these approaches increase the acquisition time necessary for both EBSD pattern collection and orientation mapping.
Neighbor Pattern Averaging & Reindexing (NPAR™)

With NPAR™, the collected EBSD pattern is averaged with all the closest surrounding EBSD patterns on the mapping grid and then reindexed. This approach reduces the image noise similar to frame averaging, but without the associated time penalty. This improves the SNR of the pattern and allows the EBSD detector to be operated at higher gain settings than conventionally used without sacrificing indexing performance.

Features and Benefits

  • EBSD detectors can be operated at higher noise levels than conventional indexing
  • Faster acquisition rates than traditional frame indexing
  • Allows for fast collection rates at constant beam current or constant collection rates at lower beam currents and energies
  • Ideal for beam-sensitive samples and non-conductive samples
  • Ideal for in-situ and 3D experiments