A continuously pumped, mode-locked laser is disclosed, which includes a cavity dumper that can remove a constant fraction of the light from the cavity at every 1/f period of time, independent of the time at which the first pulse in a train is initiated. The cavity dumper includes a modulator and two output arms, denoted as a primary output arm and a secondary output arm. When a user desires a train of pulses, the pulses are directed to the primary output arm. Between trains of pulses, when no pulse is desired by the user, the pulses are directed to the secondary output arm, which terminates in an absorber or at a secondary optical system. In this manner, the energy contained in each output pulse is essentially constant, from pulse-to-pulse and from train-to-train. This may overcome the disadvantage of many lasers that have a single output arm, in which the first pulse in a train may have an energy that depends on the length of the inactive period that immediately precedes the train.