초록

A high power integrated fiber laser system includes cascaded amplifiers that utilize low numerical aperture fiber amplifiers. The system is rugged and lightweight.

대표청구항 ▼

1. A fiber laser amplifier comprising: a seed laser configured to produce a seed pulse at a pulse repetition rate of about 10 Hz to about 100 Hz;a fiber preamplifier configured to receive and amplify the seed pulse, said fiber preamplifier having a first core diameter; a fiber power amplifier compri

1. A fiber laser amplifier comprising: a seed laser configured to produce a seed pulse at a pulse repetition rate of about 10 Hz to about 100 Hz;a fiber preamplifier configured to receive and amplify the seed pulse, said fiber preamplifier having a first core diameter; a fiber power amplifier comprising a low numerical aperture, coiled clad fiber, having a core diameter larger than said first core diameter; anda coupler configured to couple said fiber preamplifier to said fiber power amplifier. 2. The fiber laser amplifier according to claim 1, wherein said low numerical aperture is between about 0.06 and 0.08. 3. The fiber laser amplifier according to claim 1, further comprising a tapered fiber bundle connected to a cladding of said fiber power amplifier configured to direct pump energy into said cladding. 4. The fiber laser amplifier according to claim 1, further comprising: a first pumping device configured to pump said fiber preamplifier,a second pumping device configured to pump said fiber power amplifier, anda synchronizing device configured to synchronize the seed pulse with said pumping devices. 5. The fiber laser amplifier according to claim 1, further comprising one or more additional power amplifiers, wherein the core diameter each additional power amplifier increases with each subsequent power amplifier stage. 6. A method comprising: producing a seed pulse with a pulse repetition rate of about 10 Hz to about 100 Hz;amplifying the seed pulse using a fiber preamplifier having a first core diameter; andamplifying the amplified seed pulse using a fiber power amplifier that is coupled to the fiber preamplifier and that comprises a low numerical aperture, coiled clad fiber, having a second core diameter, the second core diameter being larger than the first core diameter. 7. The method of claim 6, further comprising: pumping the fiber preamplifier using a first pumping device;pumping the fiber power amplifier using a second pumping device; andsynchronizing the seed pulse with the first and second pumping devices. 8. The method of claim 6, further comprising: directing pump energy into a cladding of the fiber power amplifier using a tapered fiber bundle. 9. A pulsed fiber laser comprising: a seed laser configured to produce a seed pulse at a pulse repetition rate of about 10 Hz to about 100 Hz;a first amplifier configured to receive and amplify the seed pulse, the first amplifier having a first core diameter;a second amplifier comprising coiled clad fiber having a second core diameter, the second core diameter being larger than the first core diameter; anda coupler configured to couple the first and second amplifiers;wherein core diameters of the second amplifier and subsequent amplifiers increase with each subsequent amplifier stage. 10. The pulsed fiber laser of claim 9, further comprising a tapered fiber bundle connected to a cladding of the second amplifier configured to direct pump energy into the cladding. 11. The pulsed fiber laser of claim 9, further comprising: a first pumping device configured to pump the first amplifier,a second pumping device configured to pump the second amplifier, anda synchronizing device configured to synchronize the seed pulse with the pumping devices. 12. The pulsed fiber laser of claim 9, wherein the fiber of the second amplifier comprises a low numerical aperture.