The Beginner's Guide To Laser Beam Quality And M2 Measurement

Laser theory teaches that by design, most laser beam should have a Gaussian beam shape. The fundamental mode of the Gaussian beam (TEM₀₀) is an ideal that most laser system designers want to achieve, but in real life, nothing is perfect, and a pure Gaussian beam with a TEM₀₀ profile and a bell-shaped curve that spreads on infinitely is never achieved. This guide will introduce the concept of laser beam quality measurement with the M2 parameter, which quantifies the laser beam quality, and how to measure M2 for a real laser.