Pulsed laser sources

A method of producing laser pulses, said method comprising:

• propagating optical energy back and forth through a gain fiber by reflecting light from a pair of reflective elements on opposite ends of said gain fiber, less than about 60% of said light in said gain fiber being reflected back into said gain fiber by one of said reflectors, said pair of reflective elements together forming a resonant cavity that supports a plurality of resonant optical modes;
• substantially mode-locking said resonant optical modes to produce a train of pulses;
• propagating said train of optical pulses from said laser cavity through said one of said reflectors to a fiber amplifier along a bi-directional optical path from said laser cavity to said fiber amplifier;
• and
• amplifying said laser pulses in said fiber amplifier.

A fiber-based master oscillator power amplifier comprising:

• a mode-locked fiber oscillator comprising a resonant cavity and a gain medium, said mode-locked fiber oscillator producing a plurality of optical pulses;
• a fiber amplifier comprising a gain fiber;
• and
• a bi-directional optical path between said mode-locked fiber oscillator and said fiber amplifier permitting light from said mode-locked fiber oscillator to propagate to said fiber amplifier and light from said fiber amplifier to propagate to said mode-locked fiber oscillator,
• wherein said mode-locked fiber oscillator comprises a first segment of fiber and said fiber amplifier comprise a second segment of optical fiber and said first and second segments form a substantially continuous length of optical fiber.

A method of producing laser pulses, said method comprising:

• substantially mode-locking longitudinal modes of a laser cavity to produce laser pulses;
• propagating said laser pulses from said laser cavity to a fiber amplifier;
• amplifying said laser pulses in said fiber amplifier;
• receiving amplified spontaneous emission emitted from said fiber amplifier at said laser cavity, a first portion of said spontaneous emission entering said laser cavity;
• and
• retro-reflecting a second portion of said amplified spontaneous emission from said laser cavity back to said fiber amplifier to cause said second portion to be directed away from said cavity toward said fiber amplifier.

A fiber master oscillator power amplifier comprising:

• a mode-locked fiber oscillator comprising a first portion of optical fiber and a pair of fiber reflectors spaced apart to form a fiber optic resonator in said first fiber portion, at least one of said fiber reflectors comprising a partially transmissive fiber reflector, said mode-locked fiber oscillator outputting a plurality of optical pulses;
• and
• a fiber amplifier comprising a second portion of optical fiber optically connected to said partially transmissive fiber reflector to receive said optical pulses from said mode-locked oscillator, said second portion of optical fiber having gain to amplify said optical pulses,
• wherein said first portion of optical fiber, said partially transmissive fiber reflector, and said second portion of optical fiber comprise a continuous path formed by optical fiber uninterrupted by non-fiber optical components.