Operating Space
The graphic below gives a visual indication of the recommended operating space for BeamWatch AM. If
BeamWatch is operated outside of this space, it may be difficult to see the curvature of the caustic or the
beam may be large enough at the edges of the image that it is out of focus.
•Best results yield the strongest measurements and may be ISO when 3 Rayleigh lengths can be seen
by the camera’s detector.
•Acceptable results do not meet ISO requirements, but can still be strong, accurate measurements.
•Avoid applying lasers that fall within the Danger Zone as these results may lead to damaging fine
components in the BeamWatch AM unit.
In some cases results may fall within the Best Results area of the plot, but not state ISO. If this occurs, the
build plate location can be adjusted so the appropriate amount of Rayleigh lengths can be seen. Only make
adjustments after following the standard setup procedure and achieving an initial understanding of the beam.
The calibrated distance is measured to the center of the FOV and the detector is approximately 11mm
vertically. The build plane location can be adjusted ±5mm with the working plane still in the FOV.
If the beam focus is stable and does not experience a significant focal shift, the best practice for reaching ISO
compliance is to lower the build plate location farther than the calibrated distance by a maximum of 5mm. This
will cause the focal point to occur higher in the detector’s FOV and prevent any possible damage to the turning
mirror.
If the focal point shifts outside of the FOV then the build plate location can be raised a maximum of 5mm from
the calibrated distance to attempt to capture the entire focal shift. If the beam’s focal point falls outside of the
FOV the result accuracy is degraded.
