I am trying to find info on why there are different diameters on lenses and when one should consider changing the laser head to hold different diameters. The info I find on google, is about FL but did not find anything about lens diameters. Would anyone share a link or some knowledge?
Bigger diameters are more expensive, so you use them only when you need to.
We needed to on our latest build because the divergence on the beam was a problem at the end of a 3m beam path.