Hi all, I have a 1.5W green here that seemed at first to be emitting two beams (if you looked orthogonally at the beam, you could see a dark line straight up the middle). It was only after suitable ND filtering that I could see the beam profile, which looked to be TEM01.
The module should be TEM00 - I have two identical modules at the same power that are TEM00, with way less divergence.
Question is, what would cause it?
I thought it may be poor cooling of the laser cavity (there is an obvious beam profile change as the laser warms up over the first 30s), but that still wouldn't explain the divergence...