Why did you write my name diachi, I never posted here :crackup:Looks perfectly normal for a diode laser, at least as best I can tell from the image.
Hap, it's likely single mode but even then, you still don't get a perfectly round beam.
My PL520 output looks more square to me, but within that shape it does have a brighter oval shape....Single mode diodes have a small, round(er) emitter, where multimode diodes have larger emitters... The geometry of the emitter has a lot to do with giving the square/rectangular beam the 1W+ diodes have
Our single mode diodes usually have an oval shaped dot, however it's round enough for us to call it round.