摘要:
Apparatus and method for control of lasers (which use an array of optical gain fibers) in order to improve spectrally beam-combined (SBC) laser beam quality along the plane of the SBC fiber array via spectral-to-spatial mapping of a portion of the spectrally beam-combined laser beams, detection of optical power in each of the spatially dispersed beams and feedback control of the lasers for wavelength-drift correction. The apparatus includes a diffractive element; a source of a plurality of substantially monochromatic light beams directed from different angles to a single location on the diffractive element, wherein the diffractive element spectrally combines the plurality of light beams into a single beam. A controller adjusts characteristics of the light beams if one of the light beams has become misadjusted. In some embodiments, the controller adjusts the wavelength tuning of the respective fiber laser.
摘要:
Apparatus and method for spectral-beam combining light from a plurality of high-power fiber lasers that, in some embodiments, use two substantially identical diffraction gratings in a parallel, mutually compensating configuration to combine a plurality of separate parallel input beams each having a slightly different successively higher wavelength into a single output beam of high quality. In other embodiments, a single diffraction grating is used to combine a plurality of different wavelengths, wherein the input laser beams are obtained from very narrow linewidth sources to reduce chromatic dispersion. In some embodiments, diagnostics and adjustments of wavelengths and/or positions and angles are made dynamically in real time to maintain the combination of the plurality input beams into a single high-quality output beam.
摘要:
Apparatus and method for control of lasers (which use an array of optical gain fibers) in order to improve spectrally beam-combined (SBC) laser beam quality along the plane of the SBC fiber array via spectral-to-spatial mapping of a portion of the spectrally beam-combined laser beams, detection of optical power in each of the spatially dispersed beams and feedback control of the lasers for wavelength-drift correction. The apparatus includes a diffractive element; a source of a plurality of substantially monochromatic light beams directed from different angles to a single location on the diffractive element, wherein the diffractive element spectrally combines the plurality of light beams into a single beam. A controller adjusts characteristics of the light beams if one of the light beams has become misadjusted. In some embodiments, the controller adjusts the wavelength tuning of the respective fiber laser.
摘要:
A laser gain medium having a layered coating on at least certain surfaces of the laser gain medium. The layered coating having a reflective inner material and an absorptive scattering outside material.
摘要:
A lens duct is used for pump delivery and the laser beam is accessed through an additional component called the intermediate beam extractor which can be implemented as part of the gain element, part of the lens duct or a separate component entirely.
摘要:
A ring-laser system that includes a plurality of ring-laser gain elements and a spectral-beam-combining output stage configured to combine a plurality of beams coming from the gain elements into an output beam and that includes chromatic-dispersion compensation. In some embodiments, the output stage includes a plurality of highly reflective dielectric-coated focussing elements. In some embodiments, the output stage includes a plurality of high-efficiency dielectric-coated grating elements. In some embodiments, the output stage includes a mostly reflective but partially transmissive output mirror and a highly reflective beam-reversing mirror configured to reflect a majority of a backward-traveling signal beam such that it becomes forward traveling. In some embodiments, each gain element further includes a photonic-crystal-rod power amplifier. Some embodiments have an amplitude modulator configured to pulse the plurality of beams, and a timing controller configured to synchronize the pulses of the plurality of beams. Some embodiments further include a non-linear wavelength-conversion device.
摘要:
A method and apparatus use a photonic-crystal fiber having a very large core while maintaining a single transverse mode. In some fiber lasers and amplifiers having large cores problems exist related to energy being generated at multiple-modes (i.e., polygamy), and of mode hopping (i.e., promiscuity) due to limited control of energy levels and fluctuations. The problems of multiple-modes and mode hopping result from the use of large-diameter waveguides, and are addressed by the invention. This is especially true in lasers using large amounts of energy (i.e., lasers in the one-megawatt or more range). By using multiple small waveguides in parallel, large amounts of energy can be passed through a laser, but with better control such that the aforementioned problems can be reduced. An additional advantage is that the polarization of the light can be maintained better than by using a single fiber core.
摘要:
In some embodiments, the present invention provides an apparatus and process wherein excess stored optical energy is removed from one or more stages in a fiber-amplifier, in order to stabilize the gain and obtain a constant level of energy per pulse. In some embodiments, a method of the invention includes providing a gain fiber, optically pumping the gain fiber using pump light, amplifying seed-signal pulses having a signal wavelength using the gain fiber to obtain amplified output pulses, and automatically limiting a gain of the gain fiber. In some embodiments, an apparatus of the invention includes a gain fiber, a source of pump light coupled to the gain fiber, a source of seed-signal pulses having a signal wavelength coupled to the gain fiber, wherein the gain fiber outputs amplified signal pulses, and an automatic-gain-control mechanism configured to limit gain of the gain fiber.
摘要:
Apparatus and method for generating controlled-linewidth laser-seed-signals for high-powered fiber-laser amplifier systems. In some embodiments, the natural chirp (frequency change of laser light over a short start-up time) of a DBR laser diode when driven by pulsed current is used to broaden the linewidth of the laser output, while adjusting the peak current and/or the pulse duration to obtain the desired linewidth.
摘要:
Apparatus and method for spectral-beam combining light from a plurality of high-power fiber lasers that, in some embodiments, use two substantially identical diffraction gratings in a parallel, mutually compensating configuration to combine a plurality of separate parallel input beams each having a slightly different successively higher wavelength into a single output beam of high quality. In other embodiments, a single diffraction grating is used to combine a plurality of different wavelengths, wherein the input laser beams are obtained from very narrow linewidth sources to reduce chromatic dispersion. In some embodiments, diagnostics and adjustments of wavelengths and/or positions and angles are made dynamically in real time to maintain the combination of the plurality input beams into a single high-quality output beam.