Abstract: The present invention provides a stabile construct to facilitate connecting a spinal fixation rod to a plurality of vertebral bodies. The construct or implant comprises a housing and an insert. The housing and insert are shaped to cooperatively engage the bone screw and rod to provide a stable construct that allows for polyaxial orientation between the bone screw and the remainder of the construct.

Abstract: A photonic integrated circuit (PIC) chip comprising an array of modulated sources, each providing a modulated signal output at a channel wavelength different from the channel wavelength of other modulated sources and a wavelength selective combiner having an input optically coupled to received all the signal outputs from the modulated sources and provide a combined output signal on an output waveguide from the chip. The modulated sources, combiner and output waveguide are all integrated on the same chip.

Abstract: A digital signal channel bypass is provided as bypass around an optical network optical amplifier, in particular, an analog type optical amplifier, such as an EDFA, in an optical transport network or system. The digital signal bypass provides for an ability to maintain the existing optical amplifier OO amplification site while inserting a bypass that provides ultra low-cost OEO REGEN in a digital optical network (DON) utilizing both semiconductor electronic integrated circuit chips and semiconductor photonic integrated circuit (PIC) chips where all the optical components are in semiconductor integrated chip form providing 1R, 2R, 3R or 4R regeneration as well as other signal caring functionality. A salient feature of the digital signal bypass is to regenerate signals in the optical span that are outside the gain bandwidth of the EDFA or other such amplifier.

Abstract: A photonic integrated circuit (PIC) chip comprising an array of modulated sources, each providing a modulated signal output at a channel wavelength different from the channel wavelength of other modulated sources and a wavelength selective combiner having an input optically coupled to received all the signal outputs from the modulated sources and provide a combined output signal on an output waveguide from the chip. The modulated sources, combiner and output waveguide are all integrated on the same chip.

Abstract: A monolithic transmitter photonic integrated circuit (TxPIC) chip comprises an array of modulated sources formed on the PIC chip and having different operating wavelengths according to a standardized wavelength grid and providing signal outputs of different wavelengths. Pluralities of wavelength tuning elements are integrated on the chip, one associated with each of the modulated sources. An optical combiner is formed on the PIC chip and the signal outputs of the modulated sources are optically coupled to one or more inputs of the optical combiner and provided as a combined channel signal output from the combiner. The wavelength tuning elements provide for tuning the operating wavelength of the respective modulated sources to be approximate or to be chirped to the standardized wavelength grid. The wavelength tuning elements are temperature changing elements, current and voltage changing elements or bandgap changing elements.

Abstract: A wavelength division multiplexer (WDM) in an optical fiber transmission system launches analog signals, for instance a multi-channel television signal. The WDM enhances signal quality by transmitting along a single fiber two different optical wavelength signals, each carrying identical RF information. This results in a 3 dB improvement in carrier to noise ratio. The WDM combines two or more wavelengths centered around for instance 1550 nm or 1310 nm. A typical difference between the two wavelengths is 3 nm. In other embodiments, more than two wavelengths are used. The receiver is for instance a single photosensitive element. The phase of the two RF signals is adjusted in the optical or RF domain to be the same upon arrival at the receiver. In other embodiments, the receiver includes two photosensitive elements, each receiving from a receiver end WDM a single wavelength. In this case, the phase adjustment may be applied at the receiver in the optical or RF domain.

Abstract: An optical transmission system enables launching at least 17 dBm of optical power at 1550 nm wavelength into an e.g. 50 km long span of standard telecommunications single-mode optical fiber, without incurring unacceptable penalties from stimulated Brillouin scattering, damage to optical phase modulators from excessive drive power or thermal effects, or signal degradations caused by the SBS suppression. High frequency modulation of the laser drive current is combined with lower frequency modulation of the phase of the laser output light that is itself varied over a range of approximately 25 MHz. This two tone modulation raises the SBS threshold to greater than 17 dBm in the 1550 nm wavelength region when the laser has a line width less than 10 MHz, under cw operation. By thereby dividing the task of spectral partitioning between the laser and the phase modulator, the RF input power level to the phase modulator is manageable and the laser operates in a regime that does not cause clipping.

Abstract: The optical fiber/metallic conductor composite cable has a cable core with an optical fiber subgroup and an insulated metallic conductor subgroup. The optical fiber subgroup can be a loose tube construction, a slotted core construction, a unitube/monotube construction or a tight buffer tube construction. The individual insulated wires of the insulated metallic conductor subgroup extend longitudinally within the composite cable. Preferably, the optical fiber subgroup is on the outer periphery of the cable core to provide easy accessibility, but it can be centrally located.

Abstract: A branch point for an optical fiber stub or drop cable from a main distribution cable has an optical fiber cable splice module for protecting the optical fibers and splices from moisture and mechanical damage, providing a strong anchoring point for the optical fiber drop cable, and insuring that the minimum fiber bend radius is not violated. The splice module forms an enclosure for the splices which are held in place mechanically by rows of pins. The stub cable may also be preconnectorized.

Abstract: The present invention provides a means of inducing unidirectional oscillation in monolithic and composite ring lasers in which the light path is planar. The intracavity optical diode that enforces unidirectional oscillation in the planar ring oscillator is achieved by a combination of the nonreciprocal Faraday effect, a linear birefringence effect in which the principal axes of the birefringence are not parallel and perpendicular to the plane of propagation of the ring light path, and one or more partial polarizer effects. The present invention enables experimental optimization of polarization transformations within a planar ring oscillator, even if the oscillator is monolithic, and also provides a means of tuning the frequency of the planar ring oscillator.

Abstract: A predetermined optical fiber cable has a main trunk cable comprising a plurality of optical fibers disposed therein and multiple drop cables spliced to the trunk cable at various branch points, the preterminated fiber optic cable being completely assembled at the time of manufacture and is easily installed thereafter. At each branch point an optical fiber cable splice closure is utilized for protecting the optical fibers and splices from moisture and mechanical damage, providing a strong anchoring point for the optical fiber drop cable, and insuring that the minimum fiber bend radius is not violated. The splice closure is cylindrical in shape and has a cavity providing room for the splices and for excess optical fiber storage.

Abstract: A monolithic nonplanar ring oscillator having an optically isotropic solid-state laser body for propagating laser radiation about a nonplanar ring path internal to the laser body is disclosed. The monolithic laser body is configured to produce a 2N reflection nonplanar ring light path, where N is an integer greater than or equal to 2, comprising 2N-1 total internal reflections and one reflection at a coupler in a single round trip. Undirectional traveling wave oscillation of the laser is induced by the geometry of the nonplanar ring path together with the effect of an applied magnetic field and partial polarizer characteristics of the oblique reflection from the coupler.

Abstract: A pulling eye assembly for optical fiber cables is formed of a housing having a gripping device for gripping the multiple strength members. The first embodiment uses longitudinally extending cavities which communicate with radially directed threaded set-screw holes for receiving epoxy and/or set-screws. In the second embodiment, a pair of collets are used to grip the strength members. In both cases, a crimping sleeve is attached to an end of the cylindrical housing and being crimpably engageable with an outer surface of an optical fiber cable.

Abstract: The optical fiber cable has a plurality of centrally located optical fibers. Carrying the optical fibers is a gel-filled plastic buffer tube. A plurality of radial strength yarn threads extended along the outside of the buffer tube in a contra-helical pattern. In the armored cable embodiment, a strength and protective member in the form of a corrugated steel armor layer may be provided for additional protection against possible rodent damage. The armor is usually coated with a thin layer of plastic material in the form of a water blockable flooding compound. A ripcord is provided to assist in removal of the armor. A final polyethylene outer jacket is provided for additional cable protection. Embedded within the outer jacket is a pair of diametrically opposed, longitudinally extending strength members.

Abstract: A monolithic Nd:glass nonplanar ring laser and method for determining optimal nonplanar ring oscillator geometry for a monolithic nonplanar ring oscillator, including an arrangement for determining for a given material of a specific index of refraction and an accompanying angle of incidence the most suitable geometry for creating a monolithic nonplanar ring oscillator out of said material to produce unidirectional operation with simultaneous high differential loss and lowest overall loss. The index of refraction and angle of incidence being within a predefined range. The geometries include four, five and six bounce monolithic nonplanar ring oscillators.

Abstract: A pulling assembly for connectorized optical fiber cables is formed of a flexible metal braided hose portion for conveying a pulling force to said cable and for providing a chamber in which the cable connectors may be housed during a cable pulling operation. A cylindrical housing is attached to one end of said braided metal hose and includes a concentrically-arranged central strength member gripping apparatus and a buffer tube alignment structure disposed about the central strength member gripping apparatus. A crimping sleeve is attached to an opposite end of said cylindrical housing fixing said concentric arrangement within the cylindrical housing and being crimpably engageable with an outer surface of an optical fiber cable.

Abstract: An optical fiber cable contains a central strength member surrounded by a plurality of fiber-carrying guides traversing the length of the cable along reversing helical paths. A plurality of strength members are provided in lieu of selected symmetrically spaced guides. The strength members provide axial and torsional stability due to their reversing helical path. Periodic bandmarks are provided on each fiber for identification. An excessive length of fiber is provided in each guide to minimize fiber stress.

Abstract: Particles which enclose cavities can be produced by adding a water-insoluble solid, liquid or gaseous cavity generating compound to an aqueous solution of a matrix material. Subsequent to forming particles by dispersion in a water-insoluble dispersion medium, the matrix is rendered insoluble in water by cooling, by covalent cross-linking or by polymerization. The cavity generating compound is washed out, whereafter the particles can be used as ion exchangers in gel filtration processes, in hydrophobic chromatography or in affinity chromatography, optionally subsequent to derivatizing the particles. The particles can also be used to advantage as microcarriers in the cultivation of anchorage dependent cells.

Abstract: Reinforcement elements intended for use in door leaves of the kind consisting of fabric or similar flexible material. The reinforcement elements preferably are in the shape of tubes and have end pieces attached to their ends for cooperation with a profiled guiding member mounted in the door-frame of the door leaf in such a manner that when the door is being closed said reinforcement elements will be positioned at different predetermined levels of the door leaf, thus strengthening the latter to prevent bulging of the door leaf when the latter is exposed to heavy winds.

Abstract: A method of producing a container of plastic material capable of being oriented and/or crystallized, in which a substantially tubular blank is, in at least two mutually consecutive and mutually separate shaping phases or shaping stages, reshaped into the container. The blank is reshaped into the container by mechanical forming elements (34,42) which stretch the material in the axial direction of the blank, and in the circumferential direction of the blank. By stretching the material in each separate shaping stage to a regulated degree, there will be accumulated in the material a total stretching corresponding to the requisite stretching in order to impart to the material the desired and predetermined orientation and thereby the requisite strength properties.