NUFERN Patent applications |
Patent application number | Title | Published |
20110310913 | OPTICAL FIBER LASER, AND COMPONENTS FOR AN OPTICAL FIBER LASER, HAVING REDUCED SUSCEPTIBILITY TO CATASTROPHIC FAILURE UNDER HIGH POWER OPERATION - Optical fiber lasers and components for optical fiber laser. An optical fiber laser can comprise a fiber laser cavity having a wavelength of operation at which the cavity provides output light, the cavity including optical fiber that guides light having the wavelength of operation, the fiber having first and second lengths, the first length having a core having a V-number at the wavelength of operation and a numerical aperture, the second length having a core that is multimode at the wavelength of operation and that has a V-number that is greater than the V-number of the core of the first length optical fiber at the wavelength of operation and a numerical aperture that is less than the numerical aperture of the core of the first length of optical fiber. At least one of the lengths comprises an active material that can provide light having the wavelength of operation via stimulated emission responsive to the optical fiber receiving pump light. Components include a mode field adapter and optical fiber interconnection apparatus, which can be used to couple the first and second lengths of optical fiber, or can couple the fiber laser to an optical fiber power amplifier, which can be a multimode or single mode amplifier. | 12-22-2011 |
20110280584 | OPTICAL FIBER WITH SUPPRESSED STIMULATED BRILLOUIN SCATTERING - The present invention relates to optical fibers useful for the transmission of electromagnetic energy at such high levels of power that stimulated Brillouin scattering (SBS) may be of importance. One aspect of the present invention is an optical fiber for the propagation of optical radiation having an optical wavelength, the optical fiber and optical wavelength having an SBS acoustic wavelength associated therewith, the optical fiber comprising a core having a geometrical center and an outer perimeter; and a cladding surrounding the core; wherein the core is rare earth doped and substantially free of germanium, the optical fiber has a refractive index profile such that the core is guiding for optical radiation having the optical wavelength, and the optical fiber has an acoustic index profile such that the core is antiguiding for an acoustic wave having the SBS acoustic wavelength. | 11-17-2011 |
20110075252 | OPTICAL FIBER LASERS AND AMPLIFIERS AND METHODS FOR PROVIDING OPTICAL GAIN - The present invention relates generally to devices for the generation and amplification of electromagnetic energy. The present invention relates more particularly to optical fiber devices, such as lasers and amplifiers, useful for generating and amplifying optical energy. Accordingly, one aspect of the present invention is an optical fiber device for providing optical gain at a selected wavelength, the optical fiber device comprising: one or more sources of optical pump energy; a first length of optical fiber having a core comprising a first cross-sectional region within which the concentration of a rare earth does not fall below 50% of its highest concentration; and a second length of optical fiber comprising a core comprising a first cross-sectional region within which the concentration of the rare earth does not fall below 50% of its highest concentration, wherein the intensity of optical pump energy is higher in the first length of optical fiber than in the second, and the first cross-sectional region of the core of the second length of optical fiber is larger in area than the first cross-sectional region of the core of the first length of optical fiber. | 03-31-2011 |
20100008634 | OPTICAL FIBER ARTICLE FOR HANDLING HIGHER POWER AND METHOD OF FABRICATING OR USING - An optical fiber preform, and method for fabricating, having a first core, a second core spaced from the first core and first and second regions, the first region having an outer perimeter having a first substantially straight length and the second region having an outer perimeter having a second substantially straight length facing the first straight length. One of the regions can comprise the first core and the other comprises the second core. The preform can be drawn with rotation to provide a fiber wherein a first core of the fiber is multimode at a selected wavelength of operation and a second core of the fiber is spaced from and winds around the first core and has a selected longitudinal pitch. The second core of the fiber can couple to a higher order mode of the first core and increase the attenuation thereof relative to the fundamental mode of the first core. | 01-14-2010 |
20090262761 | PULSED LINEARLY POLARIZED OPTICAL FIBER LASER USING UNPOLARIZED Q-SWITCHED SEED LASER AND HAVING GOOD OUTPUT POWER STABILITY - Optical fiber source for providing polarized optical pulses, comprising a Q-switched fiber laser for providing substantially unpolarized seed pulses of optical energy, where the Q-switched fiber laser can comprise a laser cavity having a Q-switch and an optical fiber comprising a gain medium, where the optical fiber need not be a polarizing or polarization maintaining optical fiber; a passive polarizing element arranged to receive and substantially polarize the substantially unpolarized seed pulses; and a polarization maintaining fiber amplifier arranged for receiving the polarized seed pulses. The polarization maintaining fiber amplifier can comprise a selected polarizing or polarization maintaining fiber having a core comprising a gain medium for amplifying the substantially polarized seed pulses, where the core can be normally multimode at a an operating wavelength of the optical fiber source. The fiber amplifier can provide substantially polarized output pulses. In one practice of the invention, the pulse power instability, over at least 100 consecutive pulses, is no greater than 10%. | 10-22-2009 |
20090208877 | METHODS OF MAKING OPTICAL FIBER GRATINGS - Optical fibers and optical fiber lasers including gratings and methods of writing gratings into fibers. A method can comprise providing a photosensitive optical fiber having a region having an original refractive index (RI) profile along the elongate direction of the fiber; exposing the optical fiber to actinic radiation to alter the original RI profile to form along a length of the fiber a grating having a RI profile including alternating higher RI and lower RI sections; and wherein the maximum RI difference between a RI of a higher RI section and a RI of an adjacent lower RI section of the grating RI profile is no greater than 85% of the difference between the average index of the grating RI profile and the original RI profile. | 08-20-2009 |
20090129735 | OPTICAL FIBER HAVING REDUCED DEFECT DENSITY - An optical fiber comprising a multimode glass core having a diameter of at least 250 microns and an index of refraction and a polymer cladding having a thickness and contactingly surrounding a glass portion of the fiber so as to define an interface between the glass portion and the polymer cladding. The polymer cladding can have a first index of refraction that is less than the index of refraction. The fiber can comprise a density of less than 0.25 non-conforming regions having a diameter of 25 microns or greater per millimeter of length along the fiber, where each of the non-conforming regions is a region visible to the human eye under an optical microscope and having at least a portion thereof within a selected distance of the interface. The selected distance can be less than or equal to the thickness of the polymer cladding. The optical microscope can have a total magnification of about 200. The polymer cladding can be applied to at least a part of the optical fiber in at least a class 1000 environment. Methods of using optical fibers, including receiving with an optical fiber optical energy from a source and guiding the optical energy with the optical fiber, wherein the optical energy comprises at least one of 1) pulses each comprising a peak power of at least 10 kW, 2) an average power of at least 50 Watts, or 3) an average power density of at least 2.9 kW/cm | 05-21-2009 |
20090080835 | OPTICAL FIBER LASER, AND COMPONENTS FOR AN OPTICAL FIBER LASER, HAVING REDUCED SUSCEPTIBILITY TO CATASTROPHIC FAILURE UNDER HIGH POWER OPERATION - Optical fiber lasers and components for optical fiber laser. An optical fiber laser can comprise a fiber laser cavity having a wavelength of operation at which the cavity provides output light, the cavity including optical fiber that guides light having the wavelength of operation, the fiber having first and second lengths, the first length having a core having a V-number at the wavelength of operation and a numerical aperture, the second length having a core that is multimode at the wavelength of operation and that has a V-number that is greater than the V-number of the core of the first length optical fiber at the wavelength of operation and a numerical aperture that is less than the numerical aperture of the core of the first length of optical fiber. At least one of the lengths comprises an active material that can provide light having the wavelength of operation via stimulated emission responsive to the optical fiber receiving pump light. Components include a mode field adapter and optical fiber interconnection apparatus, which can be used to couple the first and second lengths of optical fiber, or can couple the fiber laser to an optical fiber power amplifier, which can be a multimode or single mode amplifier. | 03-26-2009 |
20090065959 | Method of Fabricating Optical Fiber - A method of making an optical fiber article can include providing an optical fiber including at least a core; providing a preform; and subsequent to the foregoing providing of the optical fiber and the preform, drawing the preform so as to dispose a region about the optical fiber. An optical fiber article can include a core; a pump cladding disposed about the core, the pump cladding for propagating pump light; and a second cladding disposed about the pump cladding, where the second cladding can provide a photonic bandgap for tending to confine pump light to a region about which the second cladding is disposed. The second cladding can comprise a plurality of layers including a first layer having a different optical property than a second layer, and the plurality of layers can be arranged as to provide the photonic bandgap effect. | 03-12-2009 |
20090016686 | OPTICAL FIBER GRATINGS FOR HANDLING INCREASED POWER LEVELS AND METHODS OF MAKING - Optical fibers and optical fiber lasers including gratings and methods of writing gratings into fibers. A method can comprise providing a photosensitive optical fiber having a region having an original refractive index (RI) profile along the elongate direction of the fiber; exposing the optical fiber to actinic radiation to alter the original RI profile to form along a length of the fiber a grating having a RI profile including alternating higher RI and lower RI sections; and wherein the maximum RI difference between a RI of a higher RI section and a RI of an adjacent lower RI section of the grating RI profile is no greater than 85% of the difference between the average index of the grating RI profile and the original RI profile. | 01-15-2009 |
20080267575 | Apparatus and Methods for Accommodating Loops of Optical Fiber - Disclosed is an optical apparatus ( | 10-30-2008 |
20080217520 | Optical Apparatus with Light Sensing - Optical apparatus comprising a generally closed housing defining an interior, an arrangement of optical elements in optical communication, the arrangement housed within the interior of the generally closed housing, and an optical sensor within the interior and arranged for sensing interior ambient light for monitoring an optical characteristic of the arrangement of optical elements. | 09-11-2008 |