Abstract: An all fiber wavelength selective coupler provides wavelength selective transfer of optical energy between two or more separated waveguides. The coupler includes signal cores that are separated enough that they can be fusion spliced to standard fibers as lead-in and lead-out pigtails. A bridge between the signal cores facilitates transfer of the optical energy through a process of evanescent coupling. In one example, the bridge is formed of a series of graded index cores.

Abstract: The present disclosure relates to an optical waveguide system. The system has a first waveguide having a core-guide and a cladding material portion surrounding and encasing the core-guide to form a substantially D-shaped cross sectional profile with an exposed flat section running along a length thereof. The core-guide enables a core-guide mode for an optical pulse signal having a first characteristic, travelling through the core-guide. A material layer of non-linear material is used which forms a second waveguide. The material layer is disposed on the exposed flat section of the cladding material portion. The material layer forms a plasmonic device to achieve a desired coupling with the core-guide to couple optical energy travelling through the core-guide into the material layer to modify the optical energy travelling through the core-guide such that the optical energy travelling through the core-guide has a second characteristic different from the first characteristic.

Abstract: A class of fibers is described that have a non-circular cross section on one or both ends that can by optimized to capture the optical radiation from a laser diode or diode array and deliver the light in the same or different shape on the opposite end of the fiber. A large multimode rectangular waveguide may be provided which can accept the radiation from a high-power diode bar and transform it into a circular cross section on the opposite end, while preserving brightness.

Abstract: The present disclosure relates to an optical waveguide system. The system has a first waveguide having a core-guide and a cladding material portion surrounding and encasing the core-guide to form a substantially D-shaped cross sectional profile with an exposed flat section running along a length thereof. The core-guide enables a core-guide mode for an optical pulse signal having a first characteristic, travelling through the core-guide. A material layer of non-linear material is used which forms a second waveguide. The material layer is disposed on the exposed flat section of the cladding material portion. The material layer forms a plasmonic device to achieve a desired coupling with the core-guide to couple optical energy travelling through the core-guide into the material layer to modify the optical energy travelling through the core-guide such that the optical energy travelling through the core-guide has a second characteristic different from the first characteristic.

Abstract: The present disclosure relates to an optical waveguide system. The system may include a first waveguide having a core-guide and a material portion surrounding and encasing the core-guide. The core-guide enables a core-guide mode for an optical signal travelling through the core-guide. A second waveguide forms a lossy waveguide on an outer surface of the first waveguide. The construction of the second waveguide is such as to achieve a desired coupling between the core-guide mode and the lossy waveguide to control an energy level of the optical signal travelling through the core-guide.

Abstract: The present disclosure relates to an optical waveguide system. The system may include a first waveguide having a core-guide and a material portion surrounding and encasing the core-guide. The core-guide enables a core-guide mode for an optical signal travelling through the core-guide. A second waveguide forms a lossy waveguide on an outer surface of the first waveguide. The construction of the second waveguide is such as to achieve a desired coupling between the core-guide mode and the lossy waveguide to control an energy level of the optical signal travelling through the core-guide.

Abstract: An all fiber wavelength selective coupler provides wavelength selective transfer of optical energy between two or more separated waveguides. The coupler includes signal cores that are separated enough that they can be fusion spliced to standard fibers as lead-in and lead-out pigtails. A bridge between the signal cores facilitates transfer of the optical energy through a process of evanescent coupling. In one example, the bridge is formed of a series of graded index cores.

Abstract: An Nd3+ optical fiber laser and amplifier operating in the wavelength range from 1300 to 1450 nm is described. The fiber includes a rare earth doped optical amplifier or laser operating within this wavelength band is based upon an optical fiber that guides light in this wavelength band. The waveguide structure attenuates light in the wavelength range from 850 nm to 950 nm and from 1050 nm to 1150 nm.

Abstract: A system for aerially surveying an area where a plane may have crashed in water and locating pings from the plane's black box using a laser on an aerial platform that produces laser pulses; using a launch telescope to direct the laser pulses to the water producing scattering from the laser pulses and a continuous stream of backscatter; using a receiving telescope to collect the continuous stream of backscatter; using an interferometer operatively connected to the receiving telescope to produce two outputs, wherein one output is the continuous stream of backscatter, and wherein the other output is a delayed replica of the first output; and using a data collection and analysis unit operatively connected to the interferometer to produce a measurement of the sound.

Abstract: Rare earth doped fiber lasers can be robust and efficient sources of high quality light, but are usually limited to the highest gain transitions of the active species. But rare earths typically possess a multitude of potentially useful transitions that might be accessed if the dominant transition can be suppressed. In fiber lasers this suppression is complicated by the very high net gain the dominant transitions exhibit; effective suppression requires some mechanism distributed along the length of the fiber. We have developed a novel waveguide with resonant leakage elements that frustrate guidance at well-defined and selectable wavelengths. Based on this waveguide, we have fabricated a Large Mode Area Neodymium doped fiber with suppression of the four-level transition around 1060 nm, and demonstrated lasing on the three-level transition at 930 nm with good efficiency.

Abstract: A system for aerially surveying an area where a plane may have crashed in water and locating pings from the plane's black box using a laser on an aerial platform that produces laser pulses; using a launch telescope to direct the laser pulses to the water producing scattering from the laser pulses and a continuous stream of backscatter; using a receiving telescope to collect the continuous stream of backscatter; using an interferometer operatively connected to the receiving telescope to produce two outputs, wherein one output is the continuous stream of backscatter, and wherein the other output is a delayed replica of the first output; and using a data collection and analysis unit operatively connected to the interferometer to produce a measurement of the sound.

Abstract: Rare earth doped fiber lasers can be robust and efficient sources of high quality light, but are usually limited to the highest gain transitions of the active species. But rare earths typically possess a multitude of potentially useful transitions that might be accessed if the dominant transition can be suppressed. In fiber lasers this suppression is complicated by the very high net gain the dominant transitions exhibit; effective suppression requires some mechanism distributed along the length of the fiber. We have developed a novel waveguide with resonant leakage elements that frustrate guidance at well-defined and selectable wavelengths. Based on this waveguide, we have fabricated a Large Mode Area Neodymium doped fiber with suppression of the four-level transition around 1060 nm, and demonstrated lasing on the three-level transition at 930 nm with good efficiency.

Abstract: An Nd3+ optical fiber laser and amplifier operating in the wavelength range from 1300 to 1450 nm is described. The fiber includes a rare earth doped optical amplifier or laser operating within this wavelength band is based upon an optical fiber that guides light in this wavelength band. The waveguide structure attenuates light in the wavelength range from 850 nm to 950 nm and from 1050 nm to 1150 nm.

Abstract: An optical source capable of enhanced scaling of pulse energy and brightness utilizes an ensemble of single-aperture fiber lasers as pump sources, with each such fiber laser operating at acceptable pulse energy levels. Beam combining involves stimulated Raman scattering using a Stokes' shifted seed beam, the latter of which is optimized in terms of its temporal and spectral properties. Beams from fiber lasers can thus be combined to attain pulses with peak energies in excess of the fiber laser self-focusing limit of 4 MW while retaining the advantages of a fiber laser system of high average power with good beam quality.

Abstract: Measurement of a distance change between a reference surface and a target is provided. A substrate has a first surface facing the target and including a grating. The grating and target combine to form an optical interferometer responsive to changes in distance between the grating and the target. A second surface of the substrate coincides with the reference surface and faces away from the target. Thickness information pertaining to the substrate is combined with results from the optical interferometer to provide a measurement of distance change between reference surface and target. The substrate is preferably a rigid material having picometer level dimensional stability.