There are two ways to do this actually. (Sorry, I just skimmed the posts above...)
Scan the terminal with your EEV, when the two icons appear, hit space. You'll get a normal hacking screen from where you can do all the sneaky stuff.
There is a guard just outside. Whistle and immediately climb back up the rope to a safe height. Too low, and he shoots you. He'll come into the room and if you time it right, you can drop down on him and knock him out. The bottom laser will be disabled, but the top one will still be activated, so you're gonna have to crouch. This may be due to a beacon in the guard's suit, but I haven't tried that out.
You can also use your OCP to disable the lasers temporarily.