Abstract: An unpolarized monochromatic light source with wavelength tunable capability wherein a monochromatic laser source (10) is connected to an incoherent cascaded fiber-ring depolarizer (14) through a single mode fiber (16) under the condition that Ld>>LC wherein Ld is the length of fiber-ring delay line (18) and LC is the coherence length of the light source (10). The combination of the monochromatic laser source (10) and the incoherent cascaded fiber ring depolarizer (14) can be further connected to an external modulator (30) for amplitude modulation, frequency modulation, or phase modulation of the light signal.

Abstract: The invention relates to a device for making a comparison between N nominal wavelength values (&lgr;ei) and the wavelength values of optical signals coupled respectively to input ports (GEl) of a phasar whose structure comprises a grating (R) of guides (Gj). According to the invention, the phasar comprises two monitoring output ports (A,B) respectively placed about focal points corresponding to two interference orders of the grating (R) designed to collect the combination of the said signals, and its structure is designed so that the transmission function approximates to a triangular shape in order to widen the monitoring span. The invention applies notably to the wavelength 15 monitoring of a tuneable optical source.

Abstract: A scheme is described for controlling adjacent channel crosstalk so that an optical receiver can accurately detect the presence of a signal in its respective optical channel after a loss of signal condition occurs. According to illustrative embodiments of the invention, crosstalk-induced cross-traffic is prevented so that traffic from an adjacent channel is not carried in a channel that is out of service due to a loss of signal condition. More specifically, adjacent channel crosstalk, which might otherwise exceed the receiver sensitivity threshold of the failed channel, is substantially reduced or eliminated so that a receiver will not improperly identify and lock onto an adjacent channel thereby causing the cross-traffic condition.

Abstract: The present invention relates to a method and a device for modulating optical signals based on modulating bending losses in bend, quantum well semiconductor waveguide sections. The complex refractive index of the optical active semiconducting components of the waveguide section is modulated by applying a variable electric or electromagnetic field. The modulation of the complex refractive index results in a modulation of the refractive index contrast and the absorption coefficient for the waveguide at the frequency of the light. By carefully adjusting the composition of the semiconducting components and the applied electric field in relation to the frequency of the modulated radiation, the bending losses (and possibly coupling losses) will provide extinction of light guided by the bent waveguide section. The refractive index contrast may be modulated while keeping the absorption coefficient substantially constant and small, whereby the guided light can be modulated only by bending losses.

Abstract: Disclosed is an optical fiber, which comprises a core and a clad of a two-layer structure including an innermost layer and an outermost layer, and has a refractive index distribution structure satisfying the conditions of 0.8% ≦&Dgr;1≦1.3 % and−0.7 % ≦&Dgr;2≦−0.4%, and also satisfying the conditions of −20≦D≦0, −0.1≦S<0 and 0≦(D/S)≦200 in a specified wavelength band having a band width of at least 20 nm in a 1.5 &mgr;m wavelength band.

Abstract: A Mach-Zehnder interferometer includes a continuous arm defining a first optical path having a length and a non-continuous arm having first and second parts with a trench defined therebetween, the non-continuous arm defining a second optical path the length of which differs from that of the first optical path. A phase shifter is selectively movable between a first position in which the phase shifter introduces no phase shift to a signal traveling along the second optical path and at least a second position at which the phase shift introduces a phase shift to the optical signal traveling along the second path relative to a signal traveling through the first optical path. A M×M optical switch using such a Mach-Zehnder interferometer.

Abstract: A method and device for tuning an optical device including an optical fiber having a core, a cladding and a Bragg grating imparted in the core to partially reflect an optical signal at a reflection wavelength characteristic of the spacing of the Bragg grating. The cladding has two variation regions located on opposite sides of the Bragg grating to allow attachment mechanisms to be disposed against the optical fiber. The attachment mechanisms are mounted to a frame so as to allow the spacing of the Bragg grating to be changed by an actuator which tunes the reflection wavelength. In particular, the variation region has a diameter different from the cladding diameter, and the attachment mechanism comprises a ferrule including a front portion having a profile substantially corresponding to diameter of the variation region and a butting mechanism butting the ferrule against the optical fiber.

Abstract: An illuminated surgical retractor includes a handle having an elongated first blade portion connected at one end to one end of the handle and an elongated second blade portion extending along the length of the first blade portion. One end of the second blade portion defines an illumination input end to which a connector is coupled. The connector is shaped to optically couple the illumination input end to a source of illumination so that at least a portion of one of the first and second blade portions is illuminated.

Abstract: An optical switch is disclosed which includes hollow waveguide structures having cantilevered beam deflectors to couple light out of the waveguide plane. An array of such waveguides with deflector combinations may be fabricated on a substrate. By combining substrates, devices such as all-optical cross bar switches, image display and scanning devices may be created.

Abstract: An optical fiber ribbon in which the location of a particular fiber contained in the ribbon can be easily identified in the field. The optical fiber ribbon includes a plurality of optical fibers arranged in parallel with and adjacent one another, and a ribbon matrix bonded to the outer coatings and encasing the plurality of optical fibers, wherein the ribbon matrix includes indicia on an outside thereof for directionally identifying a particular one of the optical fibers. According to a first aspect of the invention, the indicia includes triangle, with an apex of the triangle pointing in the direction of the particular fiber. Alternatively, according to a second aspect of the invention, the indicia includes an arrow pointing in the direction of the particular fiber. The indicia is preferably repeated at regular intervals along the length of the ribbon to allow the particular fiber to be identified along the entire length of the ribbon.

Abstract: A fiber optic transmission cable fiber protector includes a splice tube positioned over the ends of a pair of fiber optic cables having an outer capillary tube containing at least one optical fiber within an inner capillary tube. The optical fiber protector includes a pair of optical fiber strain relief mechanism positioned near the ends of the optical fibers; the strain relief mechanisms are captured within a heat sink tube that is inserted into each end of the outer capillary tubes. The splice tube is welded to the outer capillary tubes. Heat generated by the welding process dissipated by the heat sink and gases generated during the welding process are vented through a hole in the outer capillary tube into the optical fiber splice area. In an alternate embodiment a weld coupling is welded to each end of the splice tube and is further welded to the outer capillary tubes. A sealing mechanism is positioned on the inner capillary tubes within the outer capillary tubes forming a seal therebetween.

Abstract: An apparatus which couples light to a fiber from a light source at an input plane while reducing back reflections includes returning light reflected back through such that the returning light does not substantially overlap with an output of the light source in the input plane. This apparatus may include a mode matching element and/or an angular distribution altering element. The apparatus may be reciprocal. The reciprocal apparatus may prevent light traversing the apparatus again having a change in phase of light from substantially overlapping an original object in an input plane.

Abstract: An integrated photonic apparatus that includes a glass substrate having a major surface, wherein the glass substrate includes a plurality of regions, each region having a different index of refraction, including a first region having a first index of refraction and a second region having a second index of refraction lower than the first index of refraction, and a first waveguide formed along the major surface of the substrate, wherein the first waveguide has a higher index of refraction than an intrinsic index of refraction of adjacent portions of the substrate, and wherein the first waveguide passes through the first region and through the second region of the glass substrate.

Abstract: Provided is a light emitting module that capable of adjusting the wavelength of light generated under operating conditions. The light emitting module is provided with a semiconductor light emitting device 16, first and second photodetectors 20, and an etalon 18. The semiconductor light emitting device 16 has a first end face 16b and a second end face 16a, and an active layer between the first end face 16b and the second end face 16a. Each of the photodetectors 20a, 20b is located so as to receive transmitted light from the first end face 16b of the semiconductor light emitting device. The etalon 18 has a portion of a first thickness d1 located between the first end face 16b and the photodetector 20a, and a portion of a second thickness d2 located between the first end face 16b and the photodetector 20b. The first thickness d1 of the etalon 18 is different from the second thickness d2.

Abstract: Optical waveguides made of quartz glass with reduced infrared absorption and reduced attenuation coefficients are made of glass material composed of atoms having mass numbers higher than that of the natural isotope distribution. The quartz glass or doped quartz glass is made of silicon atoms, of which most or all have the mass numbers 29 and/or 30, as well as of oxygen atoms, of which most or all are composed of isotopes with the mass numbers 17 and/or 18. Atoms of the 76Ge isotope are preferably used for doping with germanium atoms having higher mass numbers than in the natural isotope mixture. Glass with atoms of preferably 30Si and/or 18O are preferably used for optical waveguides based on quartz glass having attenuation coefficients below 0.15 dB/km. As indicated, such optical waveguides are also suitable for transmitting high-energy, pulsed or continuous laser light in a wavelength range from 2.0 to 3.0 &mgr;m. These optical waveguides are also suitable for transmitting holmium laser light at 2.

Abstract: An apparatus and method is disclosed for detecting an analyte using a fiber optic electrochemical sensor that includes a fiber optic layer, an electrically conductive translucent metallic layer and a light energy absorbing dye layer.

Abstract: A jacket for a communication cable is made from a resin that has high aspect ratio filler materials, and possibly coupling agents, dispersed therein. The fillers and the coupling agents reduce the post-extrusion shrinkage of the jacketing compound such that the strength members used in the communication cable need have only negligible compressive stiffness. The communication cable may further include a skin coating surrounding the outer jacket.

Abstract: The present invention relates to a dispersion-shifted optical fiber suitable for an optical transmission line having an optical fiber amplifier with a wider amplification band. In particular, the dispersion-shifted optical fiber according to the present invention has a zero-dispersion wavelength of 1610 nm or more but 1750 nm or less, and a cutoff wavelength of 1.1 &mgr;m or more at a length of 2 m in order to suppress the bending loss to a practically permissible range, and has, with respect to light having a wavelength of 1550 nm, an effective area of 45 &mgr;m2 or more and a dispersion slope of 0.15 ps/nm2/km or less in order to suppress the occurrence of nonlinear phenomena.

Abstract: Disclosed is a low profile lighting apparatus that is particularly advantageous for use as a backlight for illuminating a display. The lighting apparatus includes a waveguide coupled to a light source for injecting light into the waveguide. The waveguide includes a plurality of elongate structures for ejecting light propagating within the waveguide through a predetermined surface of the waveguide. Another embodiment of the waveguide includes a central region of reduced thickness that redirects light propagating within the waveguide. The lighting apparatus has a low profile so it is particularly useful in areas of limited space.

Abstract: A waveguide for optical transmission having a mechanically active core material comprised of a silicon-rich silicon nitride in a mechanically active region. In the mechanically active region, the silicon-rich silicon nitride core can have no cladding (ie. an air cladding) or a cladding comprised of a silicon nitride over at least a portion thereof. The silicon-rich silicon nitride core is comprised of a silicon nitride compound having a ratio of silicon to nitrogen atoms greater than that of stoichiometric silicon nitride, Si3N4.