The NanoScan 2 has been previously shown (see the NanoScan 2 User Guide for more information) to be compliant with ISO 11146 for the measurements in Figure 2. It follows that the direct comparison above forms the foundation of the claim to compliance for BeamWatch AM. This is the best approach due to the fact that BeamWatch AM is cutting-edge technology for which established standards do not currently exist. We can claim compliance with ISO 11146 by showing that the various methods used throughout the measurement process conform to ISO, and the results match with another verifiably compliant source, in this case, the NanoScan 2.
The largest component of the previously mentioned proprietary model that is used for post-backgroundsubtraction baseline correction involves a Fourier transform method as recommended by ISO 11146-3 section 3.4. Since BeamWatch AM measures a significant length of the beam at once, including the waist, initial determination of beam waist location, beam width, divergence angles, and beam propagation ratios are easily obtained from a hyperbolic fit along the propagation axis. This procedure is detailed in ISO 11146-1 section 9, and is functionally equivalent to measuring at hundreds of locations along the beam separately with the NanoScan 2. Two items of note here are the positioning requirements of the fitting method, as well as the fact that the method applies only to beams that are stigmatic or simply astigmatic. As for the latter caveat, we assume our target users to be utilizing round fibers and any astigmatism induced by delivery heads to be simple. It is the user’s responsibility to determine if their beam is an appropriate candidate for use in BeamWatch AM. However, an operating space chart has been provided in Figure 1 to the right for further assistance.