Abstract: A method, system and apparatus for ultrasonically imaging boli that are swallowed, as they are passed through the esophagus. The trajectories of the boli are tracked, and image data corresponding to the esophagus thereby identified. Analysis of boli and esophagus image data enable esophageal parameters correlated thereto to be determined.

Abstract: A method, system and apparatus for ultrasonically imaging boli that are swallowed, as they are passed through the esophagus. The trajectories of the boli are tracked, and image data corresponding to the esophagus thereby identified. Analysis of boli and esophagus image data enable esophageal parameters correlated thereto to be determined.

Abstract: An optical waveguide designed to generate positive dispersion when operated in a high order mode. The optical waveguide in one embodiment is designed to generate positive dispersion slope, in another embodiment to generate negative dispersion slope and in yet another embodiment nominally zero dispersion slope. In one embodiment the high order mode is the LP02 mode and in another embodiment the high order mode is the LP03 mode. In another embodiment the optical waveguide is a few mode fiber. In an exemplary embodiment the optical waveguide is used in combination with a mode transformer, such as a transverse mode transformer to achieve the desired high order mode.

Abstract: A limited mode dispersion compensating optical fiber supporting at least one high order spatial mode comprising a plurality of core areas. The refractive index profile of the fiber are selected to result in an optical waveguide providing in the LP02 mode dispersion more negative than −300 ps/nm/km at a representative wavelength within an operative waveband, a projected zero dispersion (PZD) less more than 75 nm less than the representative wavelength and third order dispersion less than 2% over the operative waveband. Third order dispersion is defined as the maximum deviation from a best line fit for dispersion divided the best fit dispersion at the representative wavelength, with the best fit line being chosen to minimize the maximum deviation. In one embodiment the PZD lies between 1340 nm and 1420 nm, and in another embodiment the PZD lies between 1420 nm and 1475 nm.

Abstract: A family of fiber profiles is disclosed which exhibit only three well guided modes in the operative “band”. The reduction in the number of modes is accomplished with a change in the refractive index in the core area. The change in refractive index in the core area changes the order of the appearance of the modes, thus leading to fewer guided modes, and less MPI. In one embodiment the refractive index ring comprises an area of depressed refractive index, and the null energy point of one of the guided modes is found therein. In another embodiment, the change in the refractive index in the core is located coincidentally with the null point of a desired mode. In some embodiments negative dispersion on the order of −400 ps/nm/km is experienced, while MPI is minimized. In another embodiment the fiber profile is further characterized by a negative slope suitable for compensating a link of transmission fiber.

Abstract: An optical waveguide designed to generate positive dispersion when operated in a high order mode. The optical waveguide in one embodiment is designed to generate positive dispersion slope, in another embodiment to generate negative dispersion slope and in yet another embodiment nominally zero dispersion slope. In one embodiment the high order mode is the LP02 mode and in another embodiment the high order mode is the LP03 mode. In another embodiment the optical waveguide is a few mode fiber. In an exemplary embodiment the optical waveguide is used in combination with a mode transformer, such as a transverse mode transformer to achieve the desired high order mode.