Cesar,
Yes, you'll definitely want to do this with a counter programmed for retriggerable single pulse generation. In that mode, every trigger edge causes the counter to produce a single pulse. Note however that additional triggers which arrive before the pulse completes will be ignored.
Here's a link to an
example. There's also a little further help
here regarding some specific details in the timing.
Most multifunction boards have 2 counters available that are able to handle your timing precision without using the CPU. The timing variability for the delay and pulse time should be about 0.05 microseconds or less, and you can have a delay as small as about 0.1 microseconds.
-Kevin P.
CAUTION! New LabVIEW adopters -- it's too late for me, but you *can* save yourself. The new subscription policy for LabVIEW puts NI's hand in your wallet for the rest of your working life. Are you sure you're *that* dedicated to LabVIEW? (Summary of my reasons in this post, part of a voluminous thread of mostly complaints starting here).