Patent ID: 8537459

Claim:
A high power fiber amplifier system comprising: a passively mode locked oscillator generating optical pulses at a repetition rate; a fiber amplifier disposed downstream from said oscillator and arranged to receive at least a portion of said optical pulses from said oscillator; a controller operatively coupled to at least said oscillator, said controller comprising an element for monitoring a repetition rate of said oscillator, said element comprising a photodetector to receive and convert a fraction of the optical power of said optical pulses from said oscillator into electrical signals representative of said repetition rate, said controller capable of determining said repetition rate from said electrical signals and calculating a required down counter divide ratio needed to obtain a desired lower repetition rate, and a reference oscillator that generates a reference signal; and a means for synchronizing said passively mode locked oscillator with the reference signal, wherein pulses with a desired repetition rate are output from the high power amplifier system notwithstanding variations in the oscillator repetition rate as a function of time or temperature.