| Patent application number | Description | Published |
|---|
| 20090090614 | Thermophoretic fractionalization of small particles - Described is a method for fractionalizing nanoparticles according to the conductivity of the particle, thus enabling the production of large numbers of particles with uniform conductivity. The method is based on a modified thermophoresis process wherein a temperature gradient is produced in a mixture of particles and the most conductive particles are selectively deposited on a warm surface. In contrast to conventional thermophoresis methods, the temperature gradient that drives the fractionalization process is produced using a light source. | 04-09-2009 |
| 20090116800 | Large mode area fiber amplifiers with reduced stimulated brillouin scattering - A large mode area fiber amplifier suitable for high power applications includes a core region specifically configured to allow for high power operation while also limiting the amount of SBS that is generated. The composition of the core region is selected to include a dopant (such as aluminum) in selected areas to reduce the acoustic refractive index of the core and limit the spatial overlap between the acoustic and optical fields. The acoustic refractive index is also structured so that the acoustic field is refracted away from the central core area. In one embodiment, the core may comprise a depressed index center portion and surrounding ring core area, with the center portion including the aluminum doping and the ring formed to have a diameter less that the phonon decay length for the operating wavelength(s). | 05-07-2009 |
| 20090211303 | Accelerated aging of phosphorus-doped optical fibers - Adverse hydrogen aging limitations in multiply-doped optical fibers are overcome by passivating these optical fibers using a deuterium passivation process. This treatment essentially pre-reacts the glass with deuterium so that the most active glass sites are no longer available to react with hydrogen in service. Optical fibers of main interest are doped with mixtures of germanium and phosphorus. Optimum passivating process conditions are described. | 08-27-2009 |
| 20090214769 | Accelerated aging of phosphorus-doped optical fibers - Adverse hydrogen aging limitations in multiply-doped optical fibers are overcome by passivating these optical fibers using a deuterium passivation process. This treatment essentially pre-reacts the glass with deuterium so that the most active glass sites are no longer available to react with hydrogen in service. Optical fibers of main interest are doped with mixtures of germanium and phosphorus. Optimum passivating process conditions are described. | 08-27-2009 |
| 20100008633 | Segmented Gain-Doping Of An Optical Fiber - The present disclosure provides an approach to more efficiently amplify signals by matching either the gain materials or the pump profile with the signal profile for a higher-order mode (HOM) signal. By doing so, more efficient energy extraction is achieved. | 01-14-2010 |
| 20100027938 | Pumping in a Higher-Order Mode That is Substantially Identical To a Signal Mode - The present disclosure provides an approach to more efficiently amplify signals by matching either the gain materials or the pump profile with the signal profile for a higher-order mode (HOM) signal. By doing so, more efficient energy extraction is achieved. | 02-04-2010 |
| 20100034500 | Sequentially Increasing Effective Area In Higher-Order Mode (HOM) Signal Propagation - Disclosed are multi-stage optical amplifiers that propagate higher-order mode (HOM) signals. One embodiment, among others, comprises a first segment of optical fiber in which a first HOM signal propagates, a second segment of optical fiber in which a second HOM signal propagates, and a mode converter that converts the first HOM signal into the second HOM signal. | 02-11-2010 |
| 20100046898 | Large mode area fiber amplifiers with reduced stimulated brillouin scattering - A large mode area fiber amplifier suitable for high power applications includes a core region specifically configured to allow for high power operation while also limiting the amount of SBS that is generated. The composition of the core region is selected to include a dopant (such as aluminum) in selected areas to reduce the acoustic refractive index of the core and limit the spatial overlap between the acoustic and optical fields. The acoustic refractive index is also structured so that the acoustic field is refracted away from the central core area. In one embodiment, the core may comprise a depressed index center portion and surrounding ring core area, with the center portion including the aluminum doping and the ring formed to have a diameter less that the phonon decay length for the operating wavelength(s). | 02-25-2010 |
| 20100103959 | Selectively Pumping A Gain-Doped Region Of An Optical Fiber - The present disclosure provides an approach to more efficiently amplify signals by matching either the gain materials or the pump profile with the signal profile for a higher-order mode (HOM) signal. By doing so, more efficient energy extraction is achieved. | 04-29-2010 |
| 20100148383 | Method of controlling longitudinal properties of optical fiber - A method of creating optical fiber to exhibit predetermined length-dependent characteristics (e.g., chromatic dispersion, polarization mode dispersion, cutoff wavelength, birefringence) includes the steps of: characterizing the fiber's selected characteristic(s) as a function of length; and performing a “treatment” which modifies the refractive index over the given length to adjust the defined parameter to fall within a defined tolerance window. These steps may be repeated one or more times until the measure of the parameter falls with the defined tolerance limits. The treatment process may include, for example, a low energy actinic radiation exposure, anneal, mechanical strain, DC voltage, plasma application, etc. Indeed, if the treatment process is repeated, a different technique may be used to adjust the refractive index (“different” processes include, for example, modifying the strength/time of a UV exposure, temperatures for annealing, etc.). | 06-17-2010 |
| 20100290106 | Cascaded Raman Fiber Laser System Based on Filter Fiber - A light generation and amplification system includes a length of laser-active filter fiber having a refractive index profile that suppresses unwanted Stokes orders at wavelengths longer than a target wavelength and that has normal dispersion over its operating wavelength. A nested series of reflectors is provided at the fiber's input and output ends, and are configured to provide a nested series of Raman cavities, separated in wavelength by approximately the respective Stokes shifts. The first cavity in the series is a combined cavity that provides laser oscillation due to a combination of ionic gain and feedback at a selected first wavelength and that provides Raman gain to light at the first Stokes shift of the first wavelength when light at the first wavelength has an energy exceeding a Raman scattering threshold. The Raman cavities provide a stepwise transition between the first wavelength and the target wavelength. | 11-18-2010 |
