Patent ID: 8593725

Claim:
An optical pulse source comprising: a seed optical source for providing seed optical radiation; a pulsed optical amplifier (POA) optically coupled to the seed optical source for amplifying the seed optical radiation in dependence upon an electrical pulse signal applied thereto, and for producing a pulsed optical signal comprising optical pulses of a pulse duration defined by the electrical pulse signal, wherein the pulsed optical amplifier comprises a semiconductor optical amplifier (SOA); a POA controller for providing the electrical pulse signal to the pulsed optical amplifier; an optically isolating device disposed in an optical path between the seed optical source and the pulsed optical amplifier for preventing back reflections into the seed optical source; and, an output optical port for outputting the pulsed optical signal; wherein the electrical pulse signal comprises pulses of electrical current for producing the optical pulses in the output pulse signal, and a variable cw electrical current for varying an optical absorption of the SOA in-between the electrical current pulses, and wherein the POA controller is configured for varying the cw electrical current when a pulse repetition rate of the electrical current pulses is varied for maintaining a constant average optical power of the output pulse signal.