43results about How to "Maximizing coefficient" patented technology

An optical fiber coupler capable of providing a low loss, high coupling coefficient interface between conventional optical fibers and optical waveguide devices is provided. The novel coupler, which may be polarization maintaining, if a polarization maintaining preform is used in its fabrication includes a core, a cladding, a first end for interfacing with an optical fiber and a second end for interfacing with an optical waveguide device. The sizes of the core and cladding are gradually reduced from the first end to the second end in accordance with a predetermined reduction profile. Various parameters, such as refractive indices and sizes of the core and cladding and the reduction profile are selected to produce a low numerical aperture at the first end and a high numerical aperture at the second end, while advantageously minimizing insertion loss and maximizing the coupling coefficient at each end. In another embodiment, the novel coupler includes a secondary cladding which is also reduced between the first and second ends to improve the strength of the coupler structure at the second end. In yet another embodiment, one or two novel couplers are formed along with a chiral fiber based optical waveguide device as a single continuous element. The optical fiber preform used to fabricate the novel optical fiber coupler can be etched prior to fabrication to facilitate application of the reduction profile.

An optical fiber coupler array capable of providing multiple low loss, high coupling coefficient interfaces between a predetermined number of low numerical aperture optical fibers and an optical waveguide device with at least a corresponding number of waveguide interfaces. The novel coupler array includes a plurality of coupler inner cores and a plurality of corresponding coupler outer cores, within a medium surrounding each outer core, and also includes a first end for interfacing with optical fibers and a second end for interfacing with a plurality of waveguide interfaces of an optical waveguide device. The sizes of the inner and outer cores are gradually reduced from the first end to the second end in accordance with at least one predetermined reduction profile, such that the coupler array comprises a plurality of low numerical aperture waveguides at the first end, and a plurality of high numerical aperture waveguides at the second end.

A method of operating a wind turbine having a rotor with a plurality of blades, and one or more pitch mechanisms for rotating the blades including a sub-nominal zone of operation and a supra-nominal zone of operation for wind speeds above the nominal wind speed wherein the sub-nominal zone of operation includes a first, a second and a third operational range. The first operational range extends from a cut-in wind speed to a first wind speed, wherein the rotor speed is kept substantially constant at a first value. The second operational range extends from the first wind speed to a second wind speed, wherein both the rotor speed and generator torque are varied as a function of wind speed. The third operational range extends from the second wind speed to the nominal wind speed, wherein the rotor speed is kept substantially constant at a second value, and wherein in the second operational range, the generator torque, T, is determined in accordance with T=k·co2, wherein co is the generator speed and k is non-constant over the second operational range.

The invention includes linkage assemblies comprising coupled links with metallic contact surfaces with improved stiffness. The inventors found significant mechanical problems with all previous descriptions of metallic contact links sufficient to preclude their commercial use. These metallic contact links are a significant improvement over existing plastic ball and metal joint, or all plastic beads as found in the prior art. The invention includes methods providing these links and high friction couplings between them, as well as the linkage assemblies and flexible arms resulting from these processes.