PD ISO/TR 11146-3:2004

Foreword
Introduction
1 Scope
2 Second-order laser beam characterization
  2.1 General
  2.2 Wigner distribution
  2.3 First- and second-order moments of Wigner distribution
  2.4 Beam matrix
  2.5 Propagation though aberration-free optical systems
  2.6 Relation between second-order moments and physical beam quantities
  2.7 Propagation invariants
  2.8 Geometrical classification
  2.9 Intrinsic classification
3 Background and offset correction
  3.1 General
  3.2 Coarse correction by background map subtraction
  3.3 Coarse correction by average background subtraction
  3.4 Fine correction of baseline offset
4 Alternative methods for beam width measurements
  4.1 General
  4.2 Variable aperture method
  4.3 Moving knife-edge method
  4.4 Moving slit method
Annex A (informative) Optical system matrices
Bibliography

Specifies methods for measuring beam widths (diameter), divergence angles and beam propagation ratios of laser beams in support of ISO 11146-1.

This part of ISO11146 specifies methods for measuring beam widths (diameter), divergence angles and beam propagation ratios of laser beams in support of ISO11146-1. It provides the theoretical description of laser beam characterization based on the second-order moments of the Wigner distribution, including geometrical and intrinsic beam characterization, and offers important details for proper background subtraction methods recommendable for matrix detectors such as CCD cameras. It also presents alternative methods for the characterization of stigmatic or simple astigmatic beams that are applicable where matrix detectors are unavailable or deliver unsatisfying results.