Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: Fiber Bragg writing devices comprising solid state lasers are provided. The solid state lasers comprise optical parametric oscillators and emit moderate peak-power output beams at wavelengths which are suitable for efficient production of fiber Bragg gratings without causing embrittlement of the optical waveguide. These solid state lasers generate output beams with wavelengths of approximately 240 nm, in order to match the primary absorption peak in the ultraviolet range for a typical optical waveguide. Some of these solid state lasers generate tunable wavelength beams using an optical parametric oscillator (“OPO”), then generate harmonics of these tunable beams. Other lasers mix the tunable beam with fixed wavelengths derived from the pump laser to reach the desired output wavelength.

Abstract: 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.

Abstract: A method and apparatus for improving the beam quality of the emissions from a multimode gain medium such as a broad-stripe laser through the use of SBC techniques is provided. In order to achieve the desired beam quality without a significant reduction in output power, discrete lasing regions are formed across the gain medium using an etalon or similar device located within the SBC cavity.

Abstract: A method and apparatus for improving the beam quality of the emissions from a multimode gain medium such as a broad-stripe laser through the use of SBC techniques is provided. In order to achieve the desired beam quality without a significant reduction in output power, discrete lasing regions are formed across the gain medium using an etalon or similar device located within the SBC cavity.

Abstract: A wide variety of Fiber Bragg writing devices comprising solid state lasers are provided. The solid state lasers emit moderate peak-power output beams which are suitable for efficient production of fiber Bragg gratings without causing embrittlement of the optical waveguide. These solid state lasers generate output beams with wavelengths of approximately 240 nm, in order to match the primary absorption peak in the ultraviolet range for a typical optical waveguide. In some embodiments, the solid state lasers comprise Ti:sapphire lasers which are tuned to produce fundamental wavelengths which are frequency-multiplied. In other embodiments, the output beam of a Ti:sapphire laser is mixed with a harmonic beam from a pump laser. Some embodiments output the third harmonic of a fundamental beam.

Abstract: Efficient devices and methods for producing ultraviolet light are provided. One such device includes a diode-pumped 946 nanometer solid state laser, a first nonlinear crystal for generating blue light at approximately 473 nanometers, and a second nonlinear crystal for doubling the frequency of the blue light to produce a fourth harmonic beam of ultraviolet light at approximately 236.5 nanometers. In some embodiments, the second nonlinear crystal is a cooled CLBO crystal angle-tuned for non-critical phase-matching to provide high conversion efficiency. Some embodiments include a second laser which emits a fundamental beam having a wavelength of more than one micron and a third nonlinear crystal for sum-frequency mixing the fundamental beam and the fourth harmonic beam to output an ultraviolet beam having a wavelength of less than 200 nanometers.

Abstract: Methods and devices are provided for converting a fundamental wavelength of a fundamental beam generated by a surface-emitting diode laser having a first resonating cavity. According to some embodiments, a first nonlinear crystal disposed in a second resonating cavity external to first resonating cavity converts the fundamental beam to a first output beam having a first output wavelength different from the fundamental wavelength. Some embodiments include a second nonlinear crystal, which may be disposed in the second resonating cavity or in a third resonating cavity, for producing a second output beam having a second output wavelength different from the first output wavelength. In some such embodiments, the second nonlinear crystal converts the wavelength of the first output beam to produce the second output beam. In some embodiments, the second nonlinear crystal interacts with the first output beam and an infrared beam from another laser device to produce the second output beam.

Abstract: A method and apparatus for generating a display is provided. In the disclosed system, each color required by the display is generated by incoherently combining the beams of tens or hundreds of individual lasers. In order to achieve a full color display, three independent IBC systems are used to generate the required three colors (e.g., red, green and blue). The output from each IBC system is modulated and the three beams are combined to form a single, modulated output beam that is directed to a display scanner.

Abstract: A laser via drilling system, and a method of use thereof, is provided. The apparatus uses two or more laser systems to achieve processing parameter flexibility. The output beams from the independently controlled laser systems are combined using a beam splitter that combines the beams into single or multiple processing beams. The operational flexibility of the system can be further enhanced through the use of multiple EO modulators and a polarization sensitive beam splitter.

Abstract: A method and apparatus for performing optical coherence tomography using a wavelength multiplexed source is provided. The single output beam of the source is of a large bandwidth, thus providing a high resolution tomography system. In order to achieve high contrast as well, the wavelength multiplexed source has minimal wavelength separation between spectrally adjacent lasers and has an output beam with an approximately Gaussian spectral shape. The source is preferably comprised of one or more multi-gain element arrays multiplexed together within a single external resonator cavity. Interposed between the array and the resonator cavity output coupler are a collimating element and a diffraction grating. The collimating element can be a refractive optic, a reflective optic, or, for some applications, a ¼ pitch GRIN lens. The diffraction grating can either be transmissive or reflective.

Abstract: A wide variety of Fiber Bragg writing devices comprising solid state lasers are provided. The solid state lasers emit moderate peak-power output beams which are suitable for efficient production of fiber Bragg gratings without causing embrittlement of the optical waveguide. These solid state lasers generate fourth harmonic output beams with wavelengths of approximately 240 nm, in order to match the primary absorption peak in the ultraviolet range for a typical optical waveguide. Some of these solid state lasers comprise a frequency-doubling crystal and a CLBO crystal used in a non-critically phase-matched orientation as a frequency-quadrupling crystal. In such lasers, both the frequency-doubling crystal and frequency-quadrupling crystal are preferably engineered to minimize or eliminate beam “walkoff.

Abstract: A method and apparatus for generating a display is provided. In the disclosed system, each color required by the display is generated by incoherently combining the beams of tens or hundreds of individual lasers. In order to achieve a full color display, three independent IBC systems are used to generate the required three colors (e.g., red, green and blue). The output from each IBC system is modulated and the three beams are combined to form a single, modulated output beam that is directed to a display scanner.

Abstract: A method and apparatus is provided that enables an IBC system to operate over a large field angle. As a consequence, wide laser gain arrays can be used providing greater control over the output power and the bandwidth of the IBC system. The IBC resonator cavity is comprised of a reflector, preferably deposited on the back facets of the gain element array, and an output coupler. Interposed between the array and the output coupler is a wavelength dispersive element, such as a diffraction grating, and a collimating optic. A lens system, comprised of either a single cylindrical lens, a single cylindrical lens in combination with an array of orthogonally positioned cylindrical lens elements, or an array of individual lens elements, is located between the laser gain array and the collimating optic. At a minimum, the lens system reduces the divergence of the light from each emitter in the fast axis, thus allowing smaller, less optically complex optics to be used for the IBC resonator optics.

Abstract: A wide variety of Fiber Bragg writing devices comprising solid state lasers are provided. The solid state lasers emit moderate peak-power output beams which are suitable for efficient production of fiber Bragg gratings without causing embrittlement of the optical waveguide. These solid state lasers generate output beams with wavelengths of approximately 240 nm, in order to match the primary absorption peak in the ultraviolet range for a typical optical waveguide. In some embodiments, the solid state lasers comprise Ti:sapphire lasers which are tuned to produce fundamental wavelengths which are frequency-multiplied. In other embodiments, the output beam of a Ti:sapphire laser is mixed with a harmonic beam from a pump laser. Some embodiments output the third harmonic of a fundamental beam.

Abstract: An apparatus for combining the outputs from multiple gain elements of an array within a single resonator cavity to achieve a predetermined spectral output or improved output power is provided. The resonator cavity is comprised of a reflector, preferably deposited on the back facets of the gain element array, and an output coupler. Interposed between the gain element array and the output coupler are an optical element and a reflective diffraction grating. The optical element can be comprised of either a GRIN lens or a uniform index element with a shaped, reflectively coated back surface. The output coupler can be directly coupled to an optical fiber, for example by burying the output coupler into the entrance aperture of the fiber.

Abstract: A method and apparatus for achieving broad gain bandwidth in a Raman amplifier using a wavelength multiplexed pump source is provided. The pump source offers high power, broad bandwidth, and the ability to tailor the pump spectrum, thus providing a means to achieve gain flattening within a specific band of the Raman amplifier. The pump source is preferably comprised of one or more multi-gain element arrays multiplexed together within a single external resonator cavity. Interposed between the array and the resonator cavity output coupler are a collimating element and a diffraction grating. The collimating element can be a refractive optic, a ¼ pitch GRIN lens, or a reflective optic. The diffraction grating can either be transmissive or reflective. The combination of the diffraction grating and the collimating element forces each emitter within the array to lase at a distinct wavelength.

Abstract: Efficient devices and methods for producing ultraviolet light are provided. One such device includes a diode-pumped 946 nanometer solid state laser, a first nonlinear crystal for generating blue light at approximately 473 nanometers, and a second nonlinear crystal for doubling the frequency of the blue light to produce a fourth harmonic beam of ultraviolet light at approximately 236.5 nanometers. In some embodiments, the second nonlinear crystal is a cooled CLBO crystal angle-tuned for non-critical phase-matching to provide high conversion efficiency. Some embodiments include a second laser which emits a fundamental beam having a wavelength of more than one micron and a third nonlinear crystal for sum-frequency mixing the fundamental beam and the fourth harmonic beam to output an ultraviolet beam having a wavelength of less than 200 nanometers.