Hi forum.
It may not be the best place to ask but I will give a try.
I tried to use 488nm diode OBIS laser with SLM, and got one problem.
Fringes in the light reflected from SLM were unstable.
On the beginning I was blaming SLM flickering, but I ruled it out.
If I replace the OBIS laser with HeNe 633 nm, fringes are dead stable.
It looks like OBIS laser becomes 'unstable' after a spatial filter.
If I look on fringes before spatial filter they are stable for both lasers.
I cannot come up with an explanation of the fact. Any hints?
Thanks,
Petro