Patent application number | Description | Published |
20080285907 | Systems and methods for creating localized refractive index modulations in an optical fiber - A technique is described for creating a localized modulation of an optical fiber's refractive index profile. A segment of optical fiber is loaded into a heating unit having a resistive heating element with a localized heating zone. A selected portion of the fiber segment is positioned within the heating zone, and the heating unit is used to create a refractive index modulation the selected fiber portion. The localized modulation is repeated along the length of the fiber segment to write a fiber grating. Also described is a resistive heating system for performing the described technique. | 11-20-2008 |
20110097046 | Stretcher Fiber and Module - A stretcher fiber has a core region, inner trench region, ring region, outer trench region, and outer cladding region. The fiber regions are structured to provide the stretcher fiber with a relationship between dispersion and wavelength, such that the second and third derivatives of the stretcher fiber's propagation constant with respect to angular frequency have a shape and wavelength range matching those of a selected compressor module. | 04-28-2011 |
20130223851 | Dispersion-Compensating System And Dispersion-Compensating Fiber with Improved Figure of Merit - A dispersion-compensating system and a dispersion-compensating fiber have an improved figure of merit and effective area. The dispersion-compensating system comprises a bulk dispersion-compensating module for providing optical-domain bulk dispersion compensation for an optical signal transmission. Additionally, the system may further comprise residual dispersion compensation, which can be performed in the electrical domain following coherent detection of both amplitude and phase of an optical signal. The dispersion-compensating fiber comprises an up-doped core region; a down-doped trench; an up-doped ring; and an outer cladding, and is configured to have a high figure of merit (FOM). | 08-29-2013 |
20140093205 | Step-Index Few-Mode Fiber Designs For Spatial Multiplexing - A few-mode optical fiber comprises a core surrounded by a cladding, having a step index profile that is structured to support propagation of a plurality of desired signal-carrying modes, while suppressing undesired modes. The core and cladding are configured such that the undesired modes have respective effective indices that are close to, or less than, the cladding index such that the undesired modes are leaky modes. The index spacing between the desired mode having the lowest effective index and the leaky mode with the highest effective index is sufficiently large so as to substantially prevent coupling therebetween. | 04-03-2014 |
20140119700 | NON-LINEAR FIBER RESISTANT TO PERTURBATIONS - Embodiments of the present invention relate to a fiber design that achieves high nonlinearity, an effective index providing phase matching for an illustrative wavelength conversion process, and a low sensitivity to perturbations in fiber scaling. In one embodiment, a fiber comprises an inner core having an inner core radius and an inner core index, an outer core having an outer core radius and an outer core index, the outer core index being lower than the inner core index, an inner cladding, having an inner cladding radius and an inner cladding index, the inner cladding index being less than the outer core index, and an effective index of the fiber, the effective index being greater than the inner cladding index and less than the outer core index, wherein the fiber has a low perturbation sensitivity factor of dispersion to scaling less than about 20 ps/nm/km along the length of the fiber. | 05-01-2014 |
20140126915 | METHOD OF REDUCING THE MODAL GROUP DELAY IN A MULTIMODE TRANSMISSION SYSTEM - Systems and methods for reducing modal group delay when transmitting a plurality of optical signals over a transmission line that supports a plurality of modes are disclosed. The modes are converted at a plurality of positions along the transmission line so the signals in the end have minimal group delay. The method comprises the steps of receiving N number of optical signals into a multimode fiber having at least N modes, transmitting each of N signals into a mode of the at least N modes of the multimode fiber, and converting each of the N modes into another of the N modes at N positions along the transmission line, such that the net modal group delay generated between the N signals along the transmission line is minimized. | 05-08-2014 |
20140139907 | FIBER STRETCHER MODULE FOR USE IN THE 1550 NM WAVELENGTH RANGE - Embodiments of the present invention are generally related to embodiments of the present invention relate to a fiber stretchers module for use in the 1550 nm wavelength range. In one embodiment of the present invention, a fiber stretcher module for use in the 1550 nm wavelength range comprises a first fiber comprising a relative dispersion curve value of greater than about 0.0002 nm | 05-22-2014 |
20140238080 | Systems and Techniques For Fabricating Optical Fiber Gratings - A resistive heating element is used to fabricate a long-period grating mode converter. The resistive heating element creates a localized heating zone for creating an asymmetric perturbation at a periodic series of axial locations along the length of a segment of optical fiber that supports the propagation of both a symmetric mode and an asymmetric mode. In a further technique, a grating is written with an index contrast value that is higher than a selected optimum value. The heating element is then used to anneal the fiber segment so as to reduce the contrast value of the grating to the selected optimum value. | 08-28-2014 |
20140254616 | Fiber Designs For Wavelength Tunable Ultra-Short Pulse Lasers - Embodiments of the present invention generally relate to fiber designs for wavelength tunable ultra-short pulse lasers. More specifically, embodiments of the present invention relate to systems incorporating fiber designs for higher order mode fibers capable of soliton self frequency shifting where a system comprises a first fiber for shifting the wavelength from a pump wavelength to a transfer wavelength and a second fiber for shifting the pulse from the transfer wavelength to an output wavelength. In one embodiment of the present invention, a wavelength tunable short pulse fiber laser system comprises: a pulse generator for providing a pulse having an input wavelength; a mode-converter; a first designed fiber for shifting the pulse from the input wavelength to a transfer wavelength; and a second designed fiber for shifting the pulse from the transfer wavelength to an output wavelength. | 09-11-2014 |
20140334766 | OPTICAL MODE CONVERSION BY NONLINEAR EFFECTS - Embodiments of the present invention generally relate to optical mode conversion by nonlinear effects. More specifically, embodiments of the present invention relate to nonlinear mode conversion utilizing intermodal four-wave mixing to convert light between modes having different wavelengths for complex applications. In one embodiment of the present invention, a fiber comprises an input end for receiving light in a first mode at a first wavelength, and an output end for outputting light in a desired second mode at a desired second wavelength, wherein the first wavelength and the second wavelength are not the same. In many embodiments, the fiber comprises a higher-order mode fiber. | 11-13-2014 |
20150016792 | HIGHLY NONLINEAR OPTICAL FIBER WITH IMPORVED SBS THRESHOLD AND MODERATE ATTENUATION - A highly nonlinear optical fiber having an improved stimulated Brillouin scattering threshold is provided. The fiber includes a central core region made substantially from silica doped with aluminum, a trench region surrounding the central core region, and a silica cladding surrounding the trench region. The refractive index profile of the fiber is optimized. A refractive index difference of the central core region relative to the cladding (Δn+) is less than 26×10 | 01-15-2015 |