A Pockels cell with an operating range of 2 to 10 mgr;m has been designed, constructed, and tested for use with the Vanderbilt free electron laser. The Pockels cell can be continuously adjusted to switch out from 80 ns to the full 6 mgr;s duration of the FEL macropulse. The extinction ratio is better than 180:1 and the optical pulse is square with rise and fall times under 10 ns. The high voltage drivers are based on semiconductor switches that are compact and mounted directly to the Pockels cell; this design avoids problems associated with fast, high voltage pulses traveling in cables. In addition, designs for two alternative drivers to generate optical pulses with durations ranging from a few nanoseconds down to the subnanosecond regime are presented here. Prototypes using single high voltage transitions have been constructed and tested electrically. thinsp;
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