Invited Paper

Optical and Quantum Electronics

, Volume 24, Issue 9, pp S1129-S1135

First online:

Beamwidths of a diffracted laser using four proposed methods

  • D. WrightAffiliated withSpectra Physics Lasers

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The International Organization for Standardization has been preparing test methods for laser beamwidth and propagation factors. Several techniques have been proposed. The purpose of this paper is to compare the results of applying the various proposed definitions and measurement methods to the same diffracted beam. A heavily apertured laser beam is passed through a focusing lens; the beamwidth is measured at several locations on each side of the focus. The apparent beamwidth is calculated using the diameter that passes 86.5% of the light, the knife edge, the slit and the second moment methods of beamwidth measurement.