ISO 11146-4:2016 is an international standard that specifies methods for the measurement of laser beam widths (diameter) and divergence. It provides guidelines for determining the characteristics of laser beams in terms of their width, position, quality, and divergence angles. This standard plays a crucial role in assessing the performance and safety of laser systems.
Measurement Techniques
ISO 11146-4:2016 describes three main techniques for measuring laser beam widths: knife-edge, scanning slit, and shearing interferometer. The knife-edge method involves placing a blade perpendicular to the laser beam and measuring the intensity profile as the blade moves across the beam. The scanning slit method uses a moving slit to scan the beam and determine its width. The shearing interferometer technique utilizes interferometry principles to analyze the wavefront distortion caused by a beam's spatial variations.
Beam Parameters and Evaluation
This standard defines various parameters for characterizing laser beams, such as waist position, beam width at the waist, far-field divergence, M-squared factor, and beam propagation ratio. These parameters help evaluate the quality and stability of the laser system. The waist position refers to the location where the beam reaches its minimum width, and the beam width at the waist quantifies the smallest achievable focus. Far-field divergence measures how much the beam spreads out over distance. The M-squared factor represents the beam's multimode nature, while the beam propagation ratio indicates its suitability for different applications.
Applications and Importance
ISO 11146-4:2016 is essential in various industries where laser systems are widely used. These include manufacturing, telecommunications, medical, research, and defense sectors. Accurate measurement and evaluation of laser beam parameters are critical for optimizing processes, ensuring safety, and guaranteeing consistency in various applications. Compliance with this international standard enables comparability between different laser systems and facilitates quality control across industries.