Patent ID: 7760772

Claim:
A laser, comprising: a laser-resonator terminated by first and second mirrors, the laser-resonator having a longitudinal axis, an optical length, and a round trip-time dependent on the optical length; a gain-element located in the resonator; an arrangement for energizing the gain-element; an optical switch located in the resonator and arranged to permit circulation of radiation along the longitudinal axis of the resonator in a first state of the switch when the gain-element is energized, the optical switch being arranged to direct radiation out of the resonator at an angle to the longitudinal axis when not in the first state; and wherein, the optical switch is further arranged to switch progressively from the first state to a second state in a predetermined time longer than the round-trip time of the resonator, such that circulating laser-radiation is directed out of the resonator by the switch as a laser-radiation output pulse having a duration longer than the round-trip time of the resonator.