Patent ID: 8275007

Claim:
A multi-cascaded all fiber pulsed arrangement for amplifying optical discrete pulses generated by an external source, comprising: upstream and downstream fiber amplifiers each operative to amplify the discrete pulses, a stretch of an optical path, including the upstream and downstream fiber amplifiers, being provided with internal impurities defining a parasitic resonant cavity therebetween; at least one passive saturable absorber (SA) located in the parasitic cavity and coupled to output and input of respective upstream and downstream fiber amplifiers, the SA being configured with a recovery time τ<Tround_trip, where τ is a recovery time of the SA, and Tround trip is a round-trip time of light within the resonant cavity, the τ being selected to have Qsat_sa<Qsat_gb and to be sufficient to prevent emergence of self-pulsing effect in the fiber amplifiers, wherein Qsat_sa is a saturation energy of the SA and Qsat_gb is a saturation energy of fiber amplifiers.