What is ISO 11146-1 about?
ISO 11146-1 is the first part of the ISO 11146 multi-series that focuses on laser and laser-related equipment. ISO 11146-1 specifies methods for measuring beam widths (diameter), divergence angles and beams propagation ratios of laser beams. ISO 11146-1 is only applicable for stigmatic and simple astigmatic beams.
Who is ISO 11146-1 for?
ISO 11146-1 on laser and laser-related equipment is useful for test methods and laser beam width:
- Manufacturers of laser and laser-related equipment
- Research and development teams
- Quality control personnel
Why should you use ISO 11146-1?
The propagation properties of every laser beam can be characterized within the method of second-order moments by ten independent parameters. However, due to their higher symmetry most laser beams of practical interest need fewer parameters for a complete description. Most lasers of practical use emit beams that are stigmatic or simple astigmatic because of their resonator design.
ISO 11146-1 describes the measurement methods for stigmatic and simple astigmatic beams while dealing with the measurement procedures for general astigmatic beams.
What’s changed since the last update?
BS EN ISO 11146-1 supersedes BS EN ISO 11146-1:2005. BS EN ISO 11146-1:2021 includes some technical changes concerning BS EN ISO 11146-1:2005. These include:
- The terms and definitions were harmonized with the new edition of ISO 11145.
- The "principal axes" were defined more thoroughly and named as x’s and y'. Quantities related to the principal axes coordinate system refers to this definition and use x’s and y' in their indices.
- The requirements for the integration range for the determination of the second-order moments have been relaxed.

