Patent ID: 8179928

Claim:
A method, comprising: receiving, at a first end of a first laser cavity, a first optical energy having a first spectral bandwidth, the first laser cavity including a first high-reflector grating and a second high-reflector grating coupled in series between the first end and a second end of the first laser cavity; receiving, at a first end of a second laser cavity, optical energy having a second spectral bandwidth, the second laser cavity including a first high-reflector grating and a second high-reflector grating coupled in series between the first end and a second end of the second laser cavity; receiving, at a fiber coupler, optical energy from the first laser cavity having a third spectral bandwidth greater than the first spectral bandwidth and optical energy from the second laser cavity having a fourth spectral bandwidth greater than the second spectral bandwidth; passing in a first direction substantially all of the first optical energy through the first high-reflector grating and the second high-reflector grating of the first laser cavity to produce a second optical energy; after the passing the first optical energy, passing in the first direction substantially all of the second optical energy through a doped fiber coupled in series with the first high-reflector grating and the second high-reflector grating of the first laser cavity to produce a third optical energy, the third optical energy having an amplitude greater than an amplitude of the second optical energy; after the passing the second optical energy, receiving at least a portion of the third optical energy back through the doped fiber in a second direction opposite the first direction to produce a fourth optical energy; and receiving at the doped fiber a first portion of the fourth optical energy reflected from the first high-reflector grating of the first laser cavity and a second portion of the fourth optical energy reflected from the second high-reflector grating of the first laser cavity in the first direction to collectively produce a fifth optical energy, the fifth optical energy having the third spectral bandwidth greater than the first spectral bandwidth.