Abstract
This paper provides brief descriptions of recent developments in the basic formulas and measurement methods for determining laser beam-quality. The M2 factor concept has been studied in order to describe the laser beam quality of real laser beams, including potentially multimode and arbitrarily distorted laser beams. The study shows that the M2 value can be determined by measuring the beam spot sizes around the beam-waist. In addition, various methods for measuring beam spot sizes are discussed. Finally, the beam quality of fiberbundled diode lasers is evaluated by the moving-slit method. A good agreement is obtained between the theoretical and experimental beam propagation results.
