Fast laser power modulation in 2p systems is typically done with a Pockels cell. Conoptics sells one that is optimized for common Ti:Sapph systems, and that’s what many people end up using.
Pockels cells are a type of electro-optical modulator (EOM).
Another family of devices for modulating laser power are acousto-optical modulators (AOM).
There was a discussion of EOM vs AOM back in October. Click through to read the thread.
Pros and cons AOM vs. pockels cell for 2P microscopy: Does anyone have experience with AOMs for resonant scanning turnaround blanking?
— H.A. Obenhaus (@Neuroballs) October 18, 2017
In some correspondence with Coherent, they sent me the chart above, which summarizes some of the differences between AOMs and EOMs. It’s useful, even if some of the “weaknesses” of EOMs are a bit exaggerated (aligning EOMs isn’t that difficult).
Hat tip to Evan Raba and Darryl McCoy at Coherent