Search results
In laser science, laser beam quality defines aspects of the beam illumination pattern and the merits of a particular laser beam's propagation and transformation properties (space-bandwidth criterion).
The beam quality of a laser is characterized by the M 2 factor, comparing the true shape of the beam to that of an ideal Gaussian beam. The ISO Standard 11146 defines the M 2 factor as 1: (1)M 2 = πw0θ λ M 2 = π w 0 θ λ. In Equation 1, w 0 is the beam waist, θ is the divergence angle of the laser, and λ is the lasing wavelength (Figure 1).
The M2 factor (M squared factor), also called beam quality factor or beam propagation factor, is a common measure of the beam quality of a laser beam.
Generally, laser beams exhibit a high degree of spatial coherence, which is related to a high beam quality. As a result, one obtains good focus ability and the potential to form collimated beams with very low beam divergence.
The degree to which a real laser beam approaches perfection in this regard is often referred to as the "beam quality" of the output beam, sometimes phrased as the "times diffraction limited" or TDL value of the beam.
30 cze 2019 · This article will discuss beam propagation and quality factors, including the beam quality (M 2) factor, beam parameter product (BPP), power in the bucket (PIB), and Strehl ratio, as well as which laser systems they are most suited for. Each beam-quality metric has its advantages and disadvantages, and as a result the correct metric for an ...
This lecture will review a very useful approach that has recently been developed for defining the transverse beam quality as well as other propagation parameters of arbitrary real laser beams.
