Abstract: A method and apparatus is provided for reducing impairment to an adiabatically chirped optical signal propagating in an optical communication system. The method begins by receiving an adiabatically chirped optical signal that has traversed one or more network components in the optical communication system. The optical signal has a parameter characteristic of signal quality (e.g., an extinction ratio) that is reduced at least in part by a fidelity-degrading transmission slope accumulated in the one or more network components. A fidelity-enhancing transmission slope imparted to at least one wavelength of the adiabatically chirped optical signal at one or more select points along a transmission path of the communication system so that the optical signal experiences an increase in said parameter characteristic of signal quality.

Abstract: An optical fiber connector plug includes a housing through which extends a cable containing at least one optical fiber. A ferrule, which is supported by the housing, is provided for receiving the optical fiber. The ferrule has a mating facet and an opposing rear facet located in the housing. The ferrule has at least one guide pin thru-hole and at least one optical fiber thru-hole extending between the mating facet and the opposing rear facet. The guide pin thru-hole has an opening portion extending inward from the mating facet. The opening portion is tapered outward to meet the mating facet in an oblique manner such that the opening portion has a diameter in the plane of the mating facet that is greater than a diameter of a remainder of the guide pin thru-hole.

Abstract: An optical fiber connector plug includes a housing through which extends a cable containing at least one optical fiber. A ferrule, which is supported by the housing, is provided for receiving the optical fiber. The ferrule has a mating facet and an opposing rear facet located in the housing. The ferrule has at least one guide pin thru-hole and at least one optical fiber thru-hole extending between the mating facet and the opposing rear facet. The guide pin thru-hole has an opening portion extending inward from the mating facet. The opening portion is tapered outward to meet the mating facet in an oblique manner such that the opening portion has a diameter in the plane of the mating facet that is greater than a diameter of a remainder of the guide pin thru-hole.

Abstract: A method of packaging an optical fiber laser incorporates an optical fiber laser (11) in a matrix of a curable viscous material (15). The matrix has a loss coefficient/dissipation factor high enough to dampen acoustic vibrations and a thermal diffusivity low enough to reduce transient heat flow into the optical fiber laser.

Abstract: An optical attenuator and a method of making an optical attenuator is disclosed. The method begins by arranging a first end of a first optical fiber and a second end of a second optical fiber so that they face one another in close proximity. The first and second ends of the optical fibers are then laterally offset from one another and the first end of the first fiber is fused to the second end of the second fiber to create a fusion splice. Next, the attenuation imposed on an optical signal transmitted from the first to the second optical fiber and through the fusion splice is measured to determine an initial deviation in attenuation from a prescribed value. The fusion splice is then re-fused while exerting an axially directed force on the first and second ends of the optical fiber. The measurement step is repeated to determine a subsequent deviation in attenuation from the prescribed value and the re-fusion step is repeated to reduce the subsequent deviation in attenuation.

Abstract: A method of temperature stabilizing an optical waveguide having positive thermal optical path length expansion, in particular a stable single polarization mode optical fiber distributed feed back laser or a distributed Bragg reflector optical fiber laser, comprising affixing optical waveguide to at least two points of a composite material having negative thermal expansion; said composite material comprising a resin matrix having embedded therein fibers having a negative thermal expansion coefficient, and optionally fibers having a positive thermal expansion coefficient. Further a method of packaging optical fiber lasers that acts to reduce frequency jitter and hence reduce the spectral linewidth of the laser through damping of thermal fluctuations and acoustic vibrations originating from the environment; said packaging method comprising encapsulating the fiber laser within a curable viscous substance such as silicone or other elastomer.

Abstract: A method of temperature stabilizing an optical waveguide (11, 12) having a positive thermal optical path length expansion affixes the optical waveguide to at least two points of a material having a negative thermal expansion and comprises the material of a composite of a resin matrix having embedded therein fibers having a negative thermal expansion coefficient and optionally fibers having a positive thermal expansion coefficient, whereby to provide the negative thermal expansion.

Abstract: A tunable semiconductor laser comprises a gain section having an MQW active region, a uniform pitch grating DFB region, and first waveguide. A composite reflector, including a second MQW region and a second waveguide, forms a cavity resonator with the DFB region. A tuning voltage applied to the composite reflector induces refractive index changes, thereby allowing the center wavelength to be altered.

Abstract: A tunable semiconductor laser comprises a gain section having an MQW active region, a uniform pitch grating DFB region, and first waveguide. A composite reflector, including a second MQW region and a second waveguide, forms a cavity resonator with the DFB region. A tuning voltage applied to the composite reflector induces refractive index changes, thereby allowing the center wavelength to be altered.

Abstract: A tunable semiconductor laser comprises a gain section having an MQW active region, a uniform pitch grating DFB region, and first waveguide. A composite reflector, including a second MQW region and a second waveguide, forms a cavity resonator with the DFB region. A tuning voltage applied to the composite reflector induces refractive index changes, thereby allowing the center wavelength to be altered. A dither signal applied the composite reflector broadens the spectrum of the laser output, thereby reducing SBS in fiber optic systems.

Abstract: An upgrade method in which Raman amplification is added to an existing transmission system to provide an increase in power budget and permit a substantial increase in transmission capacity either by time division multiplexing (TDM), wavelength division multiplexing (WDM), or a combination thereof. The power budget improvement permits higher transmission capacity by increasing either a single channel data rate and/or the number of wavelength division multiplexed data channels that can be accommodated by existing fiber links.

Abstract: The specification relates to a repeaterless branch powered fiber optic communications system. The system comprises an optical fiber cable trunk, configured in ring topology, with one or more telecommunications hub, and one or more branching unit serially interconnected therein. Branching units are provided as convenient add/drop points along the trunk ring from which branch fiber optic cable radially extend to cable stations. Cable stations insert and extract telecommunications traffic from the trunk ring over the branch fiber optic cables. In addition, the branch fiber optic cables are also coupled to light emitting power sources. The branch fiber optic cables deliver the energy produced from these power sources to optical amplifiers serially embedded within the branch fiber optic cables, the branching units, or the optical fiber cable trunks. The optical amplifiers convert the energy delivered from the branch fiber optic cables into amplified telecommunications signals.

Abstract: In accordance with the invention, a Ge-doped optical fiber having reduced Brillouin scattering loss is made by modulating the tension applied to the fiber during draw. The draw tension is modulated between a low range 10-50 g and a high in the range 150-250 g. The result is SBS suppression with no significant change to end-to-end fiber loss or dispersion factors.

Abstract: In accordance with the invention a multiwavelength optical fiber transmission system is provided with a passive all-fiber optical router for add/drop multiplexing. The passive router is comprised of three fiber components: 1) a fiber directional coupler, 2) a fiber reflective grating filter and 3) a fiber notch filter. The specification describes optical routers from these components ranging in complexity from a three wavelength router to an N-wavelength router.

Abstract: In accordance with the invention a multiwavelength optical fiber cross connect is provided with an active all-fiber optical router for multiplexing/demultiplexing. The router is comprised of one electronic component--a phase controller--and four fiber components: 1) a fiber directional coupler, 2) a fiber reflective grating filter, 3) a fiber tap, and 4) a fiber phase modulator. The application describes how to make optical routers from these components ranging in complexity from a single wavelength drop router to an N-port, N-wavelength router for add/drop multiplexing. The application also describes how optical wavelength routers can be combined to create optical fiber Cross connect (OXCs), ranging in complexity from 2.times.2 single wavelength OXCs to NXN, M-wavelength OXCs.