Abstract: An isotopically-altered, silica based optical fiber is provided having lower losses, broader bandwidth, and broader Raman gain spectrum characteristics than conventional silica-based fiber. A heavier, less naturally abundant isotope of silicon or oxygen is substituted for a lighter, more naturally abundant isotope to shift the infrared absorption to a slightly longer wavelength. In one embodiment, oxygen-18 is substituted for the much more naturally abundant oxygen-16 at least in the core region of the fiber. The resulting isotopically-altered fiber has a minimum loss of 0.044 dB/km less than conventional fiber, and a bandwidth that is 17 percent broader for a loss range between 0.044-0.034 dB/km. The fiber may be easily manufactured with conventional fiber manufacturing equipment by way of a plasma chemical vapor deposition technique. When a 50 percent substitution of oxygen -18 for oxygen-16 is made in the core region of the fiber, the Raman gain spectrum is substantially broadened.

Abstract: An optical switch, in which focal position of beams is adjusted to provide a high switching efficiency and a high stability in action without increasing a light source output of a control light, comprising a condensing means for making a signal light and a control light convergent and incident upon a nonlinear optical thin-film and wherein irradiation of the control light causes a change of the nonlinear optical thin-film in refractive index to thereby change the signal light into a transmitted light or a reflected light to take out the same as an output signal.

Abstract: For detecting three-dimensional shapes of an elongated flexible body, a sensor cable to be placed in a passage or channel which is formed axially and coextensively within the elongated flexible body. The sensor cable has two pairs of fiber Bragg grating strands within a tubular carrier casing. A signal light beam containing Bragg wavelength bands is projected from a light source to input same to refractive index change portions in the fiber Bragg grating strands. Reflection diffraction light signals from the refractive index change portions are received by a signal processor to measure the degree of strain at each one of the respective refractive index change portions by comparing wavelengths of the reflection diffraction light signals with reference wavelength.

Abstract: The present invention provides an optical fiber which has a hollow portion extending along the axis and which reduces degradation of the optical characteristics, and a production method thereof. An optical fiber includes a hollow core portion, and a cladding portion which surrounds the hollow core portion. The refractive index of the hollow core portion is lower than that of the cladding portion. The hollow core portion is closed at both ends of the optical fiber so as to form sealed portions. The sealed portions are formed by, for example, heating the optical fiber and softening the cladding portion. This prevents foreign material and the like from entering the hollow core portion. Ferrules of optical connectors are attached to both end faces of the optical fiber.

Abstract: A cable exit trough is mountable to a lateral trough section or first trough section either during initial assembly of the cable routing system, or at a later date. The exit trough includes a bracket portion mountable to the top edge of one of the sides of the lateral trough section. Two lead-ins are provided to lead the cable in an upward direction from the lateral trough section to the exit trough. The exit trough includes an exit trough portion extending from the bracket portion upwardly away from the lateral trough section. The exit trough portion includes a convexly curved bottom trough surface, and two convexly curved upstanding sides. The exit trough portion and the lead-ins define a cable pathway from the lateral trough section to an exit point of the exit trough portion which can either lead downwardly relative to the lateral trough section, or horizontally.

Abstract: Photon-conducting receiving and transmitting media (e.g., optical fibers) are aligned by coupling the receiving medium with a thermokinetic structure, which can include a shape memory alloy. A photon beam is directed from the transmitting medium onto the thermokinetic structure, thereby locally heating the thermokinetic structure. The heated portion of the thermokinetic structure contracts to displace other portions of the structure and the receiving medium, which is coupled therewith, toward the photon beam so as to align the media.

Abstract: An index-guiding microstructured optical fiber, having a majority of the cross-section of the core and cladding regions occupied by voids. The voids are dimensioned such that an effective index of refraction of the cladding region is less than an effective index of the core region, the optical fiber propagating light by an index-guiding effect. The attenuation and dispersion characteristics of the microstructured optical fiber, when expressed in dB/km and ps/(nm-km), respectively, each decrease in approximate proportion to the percentage of cross-sectional area occupied by the voids. An appropriate void-to-cross-sectional area ratio may be selected so as to provide an optical communications link that provides substantially increased data throughput using today's installed base of conduit and communications relay stations.

Abstract: A tellurite-based glass composition for use in EDFAs exhibits higher phonon energy without sacrificing optical, thermal or chemical durability properties. The introduction of boron oxide (B2O3) into the Er3+-doped tellurite glasses increases the phonon energy from typically 785 cm?1 up to 1335 cm?1. The inclusion of additional glass components such as Al2O3 has been shown to enhance the thermal stability and particularly the chemical durability of the boro-tellurite glasses. Er:Yb codoping of the glass does further enhance its gain characteristics.

Abstract: An optical crossbar switch comprising: a first plurality of first optic fibers having optical ends, each one of which optical ends is mounted to a different first moveable element; a second plurality of second optic fibers having optical ends, each one of which optical ends is mounted to a different second moveable element and at least one motor controllable to translate each first moveable element and each second moveable element so as to align the optical end of any first fiber and the optical end of any second fiber adjacent to and facing each other.

Abstract: An optical cross-connect system is disclosed that use reduces the number of AWGs (Arrayed-Waveguide Grating) as compared to prior art systems so that the hardware complexity is reduced while simultaneously reducing its production costs. The optical cross-connect system includes N×N AWGs for performing multiplexing/demultiplexing functions, an optical circulator for transmitting bidirectional signals via the AWGs, an optical coupler for interconnecting N individual ports of the AWGs, and an optical switching block connected to the optical coupler. One of the optical signals branched from the optical coupler is input to the optical switching block having a corresponding wavelength and distributed to a desired output terminal, and the other one of the optical signals is input to an optical switching block being out of an operable wavelength range and filtered by the optical switching block.

Abstract: The present invention discloses a color display system. The color display system includes a plurality of light emitting polymer (LEP) optical fibers each formed as plurality of light-emitting segments for emitting a specific color by using a special light emitting polymer. The light emitting segments are arranged as a two-dimensional array with each of the light emitting segments controlled to turn on and off for presenting a color image by turning on a plurality of the light emitting segments. In a preferred embodiment, each of the light emitting segments includes an indium/tin oxide (ITO) layer segment covering the LEP optical fiber wherein each of the ITO segments is connected to an ITO control voltage for turning on and off the light emitting segment.

Abstract: A light guide configuration for serial bi-directional signal transmission includes an optical signal line for carrying electromagnetic radiation along a main direction of the line, optical accesses disposed along the main direction for coupling electromagnetic radiation in and out along a direction running substantially perpendicular to the main direction of the line, and diffusers disposed inside the optical signal line and allocated to an optical access, respectively. Each of the diffusers works in conjunction with the allocated optical access such that a portion of the radiation that is carried in the optical signal line can be coupled out of the optical signal line by the diffuser through the allocated optical access, and radiation entering through the optical access can be coupled into the optical signal line through the allocated diffuser. An optical circuit board having the configuration and a method for fabricating the optical circuit board are also provided.

Abstract: A wavelength monitoring device is provided having an optical reflecting element for reflecting an incoming optical signal to a detector, wherein the device features a narrowband optical reflecting element for reflecting only a narrowband portion of the incoming optical signal to the optical reflecting element. The narrowband optical reflecting element has a reflection function having a bandwidth and shape that determines the narrowband portion of the incoming optical signal. The narrowband optical reflecting element may be a Bragg grating for spectrally processing the incoming optical signal, while the optical reflecting element may be a blazed Bragg grating for reflecting the spectrally processing incoming optical signal to the detector. The detector determines an amount of optical power reflected by the Bragg grating and discriminates between reflections of individual gratings, and is a spatial filter for providing a direct correlation between individual detector elements and a specific wavelength range.

Abstract: A gap in an optical guideway is occupied, when the switch is in its diverting condition, by a quantity of air or other gas. To change the switch to its through condition, an actuator forces a column of liquid against the gas to compress (and thereby displace) the gas in the gap with the liquid. The actuator includes a preferably wide reservoir of the liquid and a diaphragm which is flexed to force the liquid up the column against the gas. When the actuator is deactivated the compressed gas forces the column of liquid out of the gap to return the switch to the diverting condition.

Abstract: A method and system of operating a variable optical attenuator to provide a required total attenuation in a planar lightwave circuit. The method comprises providing a first Mach-Zehnder interferometer having a first and a second arm carrying signals in an arbitrary polarization state, providing a second Mach-Zehnder interferometer having a third and a fourth arm carrying signals in an arbitrary polarization state, the second Mach-Zehnder interferometer concatenated in tandem with the first Mach-Zehnder interferometer, and cooperatively operating the concatenated first and second Mach-Zehnder interferometers to obtain the required total attenuation and an effectively nil polarization dependent loss.

Abstract: The invention provides an optical fiber composition which has a high resistance to aging upon exposure to hydrogen. The inventive optical fiber does not require further treatment steps, such as passivation or hermetic coating, to meet specifications for hydrogen aging. The inventive optical fiber has a core glass composition with a germania doping concentration from 0% to 4% in weight. Decreasing the dopant concentration of germanium increases the resistance of the fiber to hydrogen by reducing the number of germanium defect sites in the core of the fiber. The optical fiber composition is advantageous for rare earth-doped fibers which are particularly sensitive to hydrogen aging.

Abstract: The invention relates to inducing a refractive index change in the glass substrate of a polymer coated optical device by using a high numeric aperture lens to focus a femtosecond laser beam through the polymeric coating to the substrate without damaging the polymeric coating.

Abstract: A design for controlling optical modes in a closely spaced weakly confined waveguide array is described wherein the crosstalk between individual waveguides is suppressed by segmented deep etched trenches. One exemplary embodiment of the invention incorporates a shallow etched ridge waveguide array at the output coupler of a semiconductor optical demultiplexer. In this situation, all higher order modes and supermodes are filtered by a sequence of deep etched trenches located between the shallow etched ridge waveguides. The trenches have a minimal effect on the single fundamental mode of the individual shallow etched waveguides because the trenches are located far enough from the ridge waveguides where an evanescent tail of the fundamental mode approaches a minimal power level. The trenches affect and suppress all other modes including higher order leaky modes and array supermodes leaving the single fundamental mode propagating in the arrayed waveguides.

Abstract: An apparatus and method for aligning one or more optical fibers is disclosed. The apparatus includes a carrier having one or more through holes and one or more plugs, each of which is sized to be received in one or more of the three or more through holes. The carrier is adapted to receive one or more waveguides. The waveguides may be aligned by inserting a plug into each of one or more through holes in a carrier; attaching a waveguide to the carrier; aligning the carrier to align the one or more waveguides with respect to an optical device attached to a substrate; and tacking one or more of the plugs to the substrate to maintain the alignment of the waveguides with respect to the optical device.

Abstract: Optoelectronic packages comprise both an optical array and base chip. The array and base chip are aligned and coupled using a combination of V-grooves, wick stops, and alignment spheres (e.g., presion ball bearings). The array and base chip are passively aligned by disposeing an optical fiber having an angled endface onto V-grooves in both the array and base chip. The base chip typically comprises an optical surface device, such as a vertical cavity, surface emitting laser or photodetector.