Abstract: The invention concerns a rolling bearing with relieved cylindrical rolling elements maintained in a cage (4) between a cylindrical inner raceway on an inner steel ring (2) and a cylindrical outer raceway on an outer steel ring (1) and bordered by at least and annular lateral flange (11) projecting substantially radially inwards on the outer ring (1). Said rolling bearing is such that at least the rolling elements (3) are made of deep nitriding steel, comprising 0.3% of C. 3% of Cr. 1% of Mo. 0.25% of V, and 0.15% of Ni, prepared by double vacuum smelting and whereof at least the white nitride surface layer has been completely eliminated from at least all the working surfaces of the rolling elements (3) coming into contact with the rings (1, 2) and/or the cage (4). The invention is useful for mounting in rotation in particular stages of aircraft turbo-compressor rotors and turbojets.

Abstract: A method of inducing phase changes in a FIR filter is provided. The FIR filter consists of a concatenation of tunable couplers and tunable delay lines made of planar waveguides fabricated in SiON technology, forming a plurality of interferometers, at least one of which carries a heater on at least one of its waveguide arms. The method includes the step of exposing at least one of the arms of the interferometers to an irradiation at UV or a smaller wavelength, thereby inducing a change in the refractive index of the waveguide arms which induces the phase difference change. The method provides a procedure that will lead to temperature-stable changes of the refractive index of the waveguides. The resulting device is temperature-stable such that it can be afterwards be heated with chromium heaters to dynamically tune its spectral response without destroying the UV-induced changes.

Abstract: Methods and systems allow an in situ determination of the magnitude of PMD in an optical network and provide an estimate of the PMD impairment in the transmitted signal even when PMD is time dependent.

Abstract: A fiber optic security sensor cable and system for using the cable. The cable includes a optical fiber encased in a first jacket, a power cable encased in a second jacket, and an overjacket encasing both the first jacket and the second jacket where the fiber is utilized to securely transmit data and provide a response to a sensed disturbance to the sensor cable. The system provides secure data transmission and power distribution via the sensor cable where one optical sensing fiber along the path of a data fiber responds to a sensed disturbance to the sensor cable. The system's sensor cable is enabled to detect disturbances at a processing unit where the sensor cable is either physically routed adjacent to the processing unit or within the processing unit. The system can further include more than one processing unit in the form of auxiliary units such as repeaters, power amplifiers, power outlets, data routers, and any similar electronic device.

Abstract: A fiber optic sensor system for acoustic measurements over a 6 kHz bandwidth, the design of which allows for multiplexity of the input side of the system, and where the optical part of the system is based on low coherence fiber-optic interferometry techniques which has a sensor Fabry-Perot interferometer and a read-out interferometer as well, that allows a high dynamic range and low sensitivity to the wavelength fluctuation of the light source, as well as the optical intensity fluctuations. A phase modulation and demodulation scheme takes advantage of the Integrated Optical Circuit phase modulator and multi-step phase-stepping algorithm for providing for high frequency and real time phase signal demodulation. The system includes fiber tip based Fabry-Perot sensors which have a diaphragm, which is used as the transducer. Pressure microphone, velocity sensor, as well as accelerometer, are built based on the fiber tip based Fabry-Perot sensors.

Abstract: Semiconductor devices having various combinations of curved waveguides and mode transformers are described. According to some exemplary embodiments, the mode transformer itself can be fabricated as all or part of the curved waveguide. For these exemplary embodiments it can be beneficial to use mode transformers whose active regions are relatively small to minimize losses associated with the introduced curvature, e.g., mode transformers that employ resonantly coupled waveguides and a tapered active waveguide in the mode transformation region. According to other exemplary embodiments, the mode transformer can be disposed along a straight portion of the waveguide, e.g., between the curved portion of the waveguide and the back facet. The present invention also provides flexibility in manufacturing by permitting different types of devices to be generated from a wafer depending upon where the devices are cleaved.

Abstract: Printed circuit/wiring boards having optical wavguides integrated into conductive layers. More specifically, copper layers used to form pads and traces are also used to form optical waveguide mirrors and other structures, preferably by removing copper from areas in which waveguides are to be formed while leaving sufficient copper in appropriate locations to be used in waveguide structures.

Abstract: This invention pertains to a novel design for an integrated optical communications device utilizing the thermo-optic effect to condition, manipulate, or alter an optical signal transmitted thereto.

Abstract: Systems and methods for back-of-die, through-wafer guided-wave optical clock distribution systems (networks) are disclosed. A representative back-of-die, through-wafer guided-wave optical clock distribution system includes an integrated circuit device with a first cladding layer disposed on the back-side of the integrated circuit device, and an core layer disposed on the first cladding layer. The core layer, the first cladding layer, or the second cladding layer can include, but is not limited to, vertical-to-horizontal input diffraction gratings, a horizontal-to-horizontal diffraction gratings, and horizontal-to-vertical output diffraction gratings.

Abstract: A recessed area formed on a substrate surface is filled with heat sink material to form a heat sink. The heat sink material has thermal conductivity greater than that of the substrate. The heat sink may have a substantially flat surface substantially flush with the substrate surface. The substrate may further include: a planar optical waveguide formed thereon positioned for optical coupling with an optical device mounted on the substrate in thermal contact with the heat sink; and/or an electrical contact layer formed thereon positioned for establishing electrical continuity with an optical device mounted on the substrate in thermal contact with the heat sink. The electrical contact may also provide thermal contact between the device and heat sink. The substrate may further include a low-index optical buffer layer formed on its surface. Materials for the substrate, buffer layer, and heat sink may include silicon, silica, and diamond, respectively.

Abstract: Optical transceivers have loopback and pass-through paths for diagnosing transceiver components and optical networks connected to the optical transceiver or for routing data out of the transceiver in a pass-through mode. The loopback paths are selectively configured so that a selected number of the components in the transceiver are included in the loopback path. Where more than one loopback path is present, a network administrator can select which components will be included in a particular test so that, depending on whether a signal is returned on the loopback path as intended, the network administrator can determine which components are operating correctly and which are faulty. The loopbacks can be configured to run on the electrical side of the transceiver from input port to output port or on the optical side from receiver to transmitter. The pass-through paths can be used to connect the transceiver to other devices.

Abstract: An optical switch comprises input channels with input optical free-space elements, an intermediate optical free-space element, and input tunable optical lenses with adjustable projection characteristic for projecting lightwaves received from the input optical free-space elements into the intermediate optical free-space element. The switch further comprises output channels with output optical free-space elements, and output tunable optical lenses with adjustable reception characteristic for capturing the lightwave from the intermediate optical free-space element and for feeding the lightwave to the output optical free-space elements. The optical switch can be integrated into a substrate. The tunable lens can be implemented with an individually tunable heater. By adjusting the heaters one can control the projection characteristic of the light beam emitted into a free-space element. Also an asymmetrical switch arrangement is possible.

Abstract: A method for calibrating a preferred disposition for a moveable first mirror of an optical switch core of a photonic crossconnect device relative to a second mirror thereof, the method comprising the steps of determining approximate geometric coordinates of the first mirror relative to the second mirror, effecting a laser light crossconnection between the first and second mirrors to produce data from which to provide first order corrections to refine the geometric coordinates, and effecting a further laser light crossconnection between the first mirror and a third mirror, to produce data from which to provide second order corrections to further refine the geometric coordinates, whereby to calibrate the first mirror such that upon initiation of a laser light crossconnection involving the first mirror, a switching element detects deviation of the first mirror from the preferred disposition thereof and effects corrective changes.

Abstract: The invention provides an optical shutter (400) for a communication system of a type comprising first (B1, B2) and second (A1, A2) communication paths along which information-bearing radiation propagates in opposite directions. The shutter (400) comprises: an optical tap (440) and a power monitor (430) for monitoring power of information-bearing radiation propagating along the first path (B1, B2) and for generating a corresponding radiation power indicative signal; a control unit (420) for comparing the indicative signal with a threshold value to generate a control signal (control); and shutter switch (410) for selectively substantially transmitting or blocking radiation propagating along the second path (A1, A2) in response to the control signal.

Abstract: In a folded three-dimensional free-space optical switch including a set of fibers and an optical system for producing collimated beamlets aligned to intersect an array of dual axis micromirrors of coplanar input and output mirror elements, and a folding mirror, the input and output micromirrors are arranged in a pattern wherein either the input or output mirror set is disposed along an annulus and wherein the complementary output or input mirror set is disposed within the annulus in order to globally minimize maximum tilt angles for a two-dimensional locus of tilt angles of the micromirror set. The beamlets are routed from assigned input fibers to corresponding input moveable mirrors to assigned output fibers via the static folding mirror and corresponding output moveable mirrors.

Abstract: An optical system and method of exciting and measuring fluorescence on or in samples treated using fluorescent pigments using such an optical system having at least one first laser (1); a mirror (4); a deflection element (7); an optic (8); and a unit (10), which includes mirror (4) and optic (8) mounted fixed in relation to one another. The unit (10) is positioned so it is linearly movable back and forth along the optical axis (5) and is mechanically connected to an oscillating linear drive (11). The optic (8) additionally acts as a collimator and the mirror (4) additionally acts to deflect the collimated light (12) parallel to the optical axis (5).

Abstract: An optical switching system that switches the path of an optical signal by moving a microstructure onto which a light-guiding structure is mounted. The microstructure is formed by a MEMs and semiconductor process to be integral to the substrate. The light-guiding structure may include waveguides. The microstructure moves from one position to another position (e.g., laterally, vertically, rotationally) such that incoming optical signals align over a small air gap to different optical paths, depending on the position of the movable microstructure. As a result, the optical signal propagate along different optical paths (e.g., straight pass through or cross over) depending on the position of the movable microstructure. The optical paths have a large radii of curvature so as to change the direction of the optical signal gradually, thereby reducing insertion losses.

Abstract: A monochromator arrangement for isolating or recombining a narrowband optical signal from a broadband signal is proposed. The arrangement has a body of rotational symmetry of a dispersive medium. In its simplest form the body is a cylinder with a continuous outer wall and two planar end surfaces. The outer wall may alternatively have a polygonal cross-section. The body forms a multi-reflective cavity, wherein a broadband optical signal entering the cavity through a planar end surface at an angle of incidence to the outer wall is repeatedly totally internally reflected off the outer wall. At least one exit point is provided in the outer wall for permitting egress of a spectral component. For recombination, narrowband optical signals are coupled into the body at different locations on the outer wall and propagated in substantially helical paths that converge at a planar surface. This arrangement permits the propagation path within the dispersive medium to be lengthened in a relatively compact space.

Abstract: An optical communication system using a four-wavelength add/drop type wavelength division multiplexer (WDM) is provided for extending a communication coverage without adding an optical line and a repeater by installing a wavelength-pass add/drop type optical module at an optical line connected between an existing transmitting station or base station and an existing receiving station or repeater. The optical communication system includes a slave unit including, a first WDM for dividing or mixing a first wavelength and a second wavelength, a second WDM which is connected to the first WDM and divides or mixes the first wavelength and the second wavelength to allow them travel through a predetermined path, a third WDM which is connected to the first WDM and divides a third wavelength and a fourth wavelength from a communication line of the second wavelength; and a fourth WDM which is connected to the second WDM and multiplexes or demultiplexes the third wavelength and the fourth wavelength.

Abstract: An apparatus for transmission of free space optical communication system signals employing a spatially-extended light source and method of using the same. A laser beam source directs an optical signal into a free end of a segment of multimode fiber. As the optical signal passes through the segment of multimode fiber, the optical signal is converted into a mode-scrambled optical signal. This mode-scrambled signal may then be used as a spatially-extended light source that is directed outward as an optical beam through the use of a collimating lens.

Abstract: Disclosed is a Fabry-Perot laser device connected with an optical transmission link. The device comprises an optical circulator for forming an optical waveguide loop and circulating light through the optical waveguide loop and for outputting light from the optical waveguide loop through an external port; an optical fiber amplifier located on the optical waveguide loop and for amplifying the light circulating in the optical waveguide loop; a laser light source connected with the exterior port and being self-seeded by the light inputted through the exterior port and for outputting wavelength-locked light to the exterior port; and, a first splitter located on the loop for splitting a portion of the circulating light and for outputting the split-off light to the optical transmission link.

Abstract: A fiber laser sensor has a fiber laser (FL) with two reflectors in the form of a first and a second Bragg grating (4, 5) and a fiber segment (3) arranged in between. The first Bragg grating (4) is arranged in a temperature-sensitive fashion. The second Bragg grating is a chirped Bragg grating (5) whose central wavelength is stabilized with regard to temperature changes. By means of this sensor, temperature and pressure can simultaneously be measured separately from one another, beat frequencies of orthogonal polarization eigenmodes of the fiber laser (FL) being a measure of the pressure and beat frequencies of longitudinal modes being a measure of the temperature.

Abstract: The present invention is directed to a novel method for preparing chirped Bragg gratings and optical communications devices fabricated therewith.

Abstract: A structure for effecting a transition from a passive waveguide to an active waveguide or from an active waveguide to a passive waveguide of the present invention. The inventive device comprises a first cladding; a first core disposed within the first cladding; and a ground plane disposed over the first cladding and the core. A second cladding is disposed on the ground plane. A second core is disposed on the second cladding. A third cladding is disposed on the second cladding and the second core and an electrode is disposed on top of the third cladding. The inventive structure enables the construction of a novel an advantageous switch comprising an input port; an output port; and plural waveguides disposed between the input port and the output port. Each waveguide includes a first cladding; a first core disposed within the first cladding; and a ground plane disposed over the first cladding and the core. A second cladding is disposed on the ground plane. A second core is disposed on the second cladding.

Abstract: An optical coupler comprises an optical tip having a small cross section. The coupler is tapered from a waveguide width to the small cross section tip. In one embodiment, the length of the taper is approximately 40 um long. The waveguide width is approximately 450 nm wide, and the tip is approximately 150×250 nm wide. The tip couples to an optical fiber, which in one embodiment is approximately 4 um wide. In a further embodiment, the waveguide tapers into a combination of multiple tips to provide a better overlap between a mode profile of the fiber and the coupler.

Abstract: A tap detector monitors an optical signal propagating through a waveguide as a portion of the optical signal is tapped and directed to the monitor detector. A precisely formed grating structure formed within the waveguide surface causes a portion of the propagating optical signal to be coupled out of the waveguide at a particular angle. The grating structure produces an angular separation of light propagating through the waveguide in opposite directions and which is directed out of the waveguide by the grating structure. A monitor detector is positioned to detect the light tapped from the optical signal and to avoid being influenced by any other signals that may be propagating in a direction opposite the optical signal and that are diffracted out of the waveguide by the grating structure.

Abstract: An optical device for use with an optical signal propagating therein comprising a first waveguide having a core which is terminated at an endface, in which either (a) the endface of the waveguide is uncontrolled (for instance not being smooth, not being optically flat, and/or not being at an angle optimised to avoid deleterious back-reflection) or (b) the first waveguide a polymer waveguide or (c) both. A second waveguide is terminated at an endface within about 50 &mgr;m of the endface of the first waveguide so that the waveguides are optically coupled. A pigtailing material is situated in the gap between the first waveguide and the second waveguide and has a refractive index within about 0.03 of the refractive index of the core of the first waveguide. When the first waveguide is a polymer waveguide, its core preferably has an effective refractive index either less than about 1.4 or greater than about 1.57 (at 1550 nm).

Abstract: An optical connector is constituted of a connector housing, a shielding case, and optical elements. The shielding case is split into a case main body section and a heatsink mechanism section, both joined together to constitute housing recesses. While the case main body section and the heatsink mechanism section are joined together, element main body sections are held between them. A non-joint plane of the heatsink mechanism section is housed in a case housing recess of the connector housing in an outwardly exposed state. A corrugated heatsink fin section is formed in the non-joint plane. The housing recesses into which the element main body sections are to be housed are partitioned from each other.

Abstract: A ferrule-less optical connector comprising: (a) a housing having a front end portion and a back end portion, the housing having at least one passageway extending from the back end portion to the front end portion to accommodate at least one fiber, the housing defining a cavity along a first portion of the passageway such that a fiber in the passageway is deflected into the cavity when the connector is in the mated state; (b) a barrier along a second portion of the passageway, the barrier preventing a fiber from being deflected into the second portion when the connector is in the mated state; (c) a fiber retainer at the back end portion, the fiber retainer adapted to restrict a fiber's backward movement with respect to the housing when in the mated state; and (d) the front end portion being configured to mate with an alignment member such that a fiber in the passageway is received within a passage of the alignment member.

Abstract: A splice module for optically interconnecting ends of first and second optical fibers (200, 300), each of which has a predetermined radius (Rf). The splice module comprises first and second plates (20, 30), both of which are made of silicon. The first plate 20 is provided with grooves (22). The second plate (30) is arranged on the first plate (20) to cover the grooves (22) and to define passage ways (26) for receiving and aligning the ends of the first and the second optical fibers (200, 300). The passage way (26) has an inscribed circle (28), which has a radius (Rj) larger than the predetermined radius (Rf) by a predetermined difference (D) between 0.5 &mgr;m and 1.0 &mgr;m, both inclusive.

Abstract: A fiber optic connector for coupling focused radiant energy from a laser to a fiber optic conductor includes a secondary transmission path and one or more reflectors and/or heat sinks for deflecting errant radiant energy to a location where it be safely dissipated. In addition, coupling of the radiant energy to the cladding of the fiber is minimized by stripping or at least partially removing the cladding to reduce the amount of cladding in the area that extends to the focal plane of the radiant energy source.

Abstract: An illuminant USB cable is constructed to include two USB connectors, each USB connector having a light permeable housing and a circuit board with a LED that emits light when the illuminant USB cable connected to a computer, a cable electrically connected between the circuit boards of the USB connectors, the cable having a light permeable tubular outer shell, and a fiber optic axially mounted within the tubular outer shell of the cable and connected between the light emitting elements of the USB connectors to receive light from the LEDs of the USB connectors and to refract light through the outer shell of the cable to the outside, the fiber optic having recessed portions for producing light spots when refracting light from the LED.

Abstract: An optical receiver comprises (a) an optical fiber, (b) a rear-illuminated type PD for receiving incoming light emerging from the optical fiber, (c) a submount supporting the PD, (d) a coaxial type package housing the submount, and (e) a preamplifier IC for amplifying electric signals from the PD. In particular, the submount is provided with a reflecting face for reflecting the incoming light so that the light can enter the PD. The submount may be provided with an optical path-forming groove having at least one reflecting face for introducing and reflecting the incoming light so that the light can enter the light-receiving portion of the PD mounted on the submount. This structure enables the production of an optical receiver most suitable for high-speed response and excellent in productivity. A method of producing the optical receiver is also offered.

Abstract: An optical connector is constituted of a connector housing, a shielding case, and optical elements. The shielding case is split into a case main body section and a heatsink mechanism section, both joined together to constitute housing recesses. While the case main body section and the heatsink mechanism section are joined together, element main body sections are held between them. A non-joint plane of the heatsink mechanism section is housed in a case housing recess of the connector housing in an outwardly exposed state. A corrugated heatsink fin section is formed in the non-joint plane. The housing, recesses into which the element main body sections are to be housed are partitioned from each other.

Abstract: The disclosed invention relates to a bi-directional optical transceiver module and method of improving the efficiency and reliability of the same, where interference from optical crosstalk and electromagnetic waves are minimized and a wavelength division multiplexing filter can be easily mounted at a predetermined inclination angle, thereby improving the efficiency and reliability of the bi-directional optical transceiver module.

Abstract: A system is provided for fusion splicing at least one pair and, more typically a plurality of pairs (e.g., 24 pairs), of optical fibers together. The system includes a pair of electrodes and a controller. The optical fibers are positioned between the pair of electrodes. In this regard, the electrodes are capable of passing an electric current therebetween to create an electric arc capable of heating an end of each of the optical fibers. The controller is capable of controlling the electrodes to thereby pass the current therebetween to create the electric arc. Advantageously, the controller is capable of controlling the electrodes to pass an initial current to thereby create and maintain an initial electric arc and thereafter pass a processing current to thereby create and maintain a processing electric arc, where the initial current is higher than the processing current.

Abstract: An optical fiber coupler reinforcing member comprises an approximately rectangular member formed by a hard material, and has a flat surface along the longitudinal direction thereof. In addition, the shape thereof in cross-section is a hexagonal shape which inscribes a cylindrical member. Furthermore, a recess having a U-shaped cross-section is formed in the longitudinal direction of the above-mentioned approximately rectangular member and houses coupling section. The coupling section housed within the recess is fixed at both ends of the recess by an adhesive or the like. In addition, both ends of the inner wall surface of the recess have been given bevel sections. As a result, the optical fiber coupler reinforcing member having high reliability at low cost, with which the strength with respect to external force is improved and with which processability and the assembly operations of the optical fiber coupler are easy, are provided.

Abstract: An optical cable includes an outer jacket comprised of a cross-linked medium density polyethylene having at least 10% of an inorganic filler therein. The filler preferably comprises at least 75% by weight MgO. In particular embodiments, the ATH content of the filler is less than 1% by weight. Also disclosed is a method for manufacturing the cable in which a jacket of thermoplastic MDPE is extruded onto a cable core and subsequently cross-linked. Moisture activated cross-linking processes are specifically disclosed.

Abstract: An optical panel includes a plurality of stacked optical waveguides bound by black cladding to collectively form an inlet face and an opposite display screen. An inlet diffuser has an inlet surface, and an opposite outlet surface adjoining the inlet face of the waveguides. Asymmetric diffusion of image light is effected by the inlet diffuser for increasing field of view, with ambient light being absorbed through the display screen for increasing contrast. Alternatively, an outlet diffuser may be provided at the display screen to complement the inlet diffuser by differently diffusing the image light spatially at the display screen.

Abstract: The present invention relates to a transmission optical fiber. The transmission optical fiber including a core and a cladding made of SiO2 is characterized in that GeO2 and F are doped in SiO2 of the core and the cladding. Therefore, a high Raman gain coefficient could be obtained while a desired dispersion value and a non-linearity are maintained, by controlling the refractive index of the core and the cladding. Further, the pump power of the laser diode could be reduced and the cost of the laser diode could be lowered accordingly. In addition, the life of the laser diode is extended since the laser diode needs not to be operated at a high output.

Abstract: The present invention provides devices and methods for dispersion compensation. According to one embodiment of the invention, a dispersion compensating device includes a negative dispersion fiber having an input configured to receive the optical signal, the negative dispersion fiber having a length and dispersion sufficient to remove any positive chirp from each wavelength channel of the optical signal, thereby outputting a negatively chirped optical signal; an amplifying device configured to amplify the negatively chirped optical signal; and a nonlinear positive dispersion fiber configured to receive the negatively chirped optical signal. The devices of the present invention provide broadband compensation for a systems having a wide range of variable residual dispersions.

Abstract: The present invention is directed to the creation of zones of permanently altered refractive index characteristics in glass waveguiding devices, including optical fibers and optical waveguides pre-existed in a glass substrate. Such zones in which the refractive index has been permanently altered are created in glass using a very high intensity laser beam which is produced by focusing the light output from an ultrafast pulsed laser at a predetermined target region in the glass. The preferred laser is a Ti:Sapphire amplified, frequency-doubled Erbium-doped fiber laser system, providing light pulses of approximately 100 femtosecond duration, each with an energy of between about 1 nanojoule and 1 millijoule, and preferably at a pulse repetition rate of between 500 Hz and 1 GHz. The repetition rate is chosen to deliver pulses faster than the thermal diffusion time over the dimensions of the volume element being modified.

Abstract: A process produces a glass overcladding tube from a silica gel body. The process includes passing the gel body through a hot zone under conditions that cause partial sintering of the gel body and repassing the gel body through the hot zone under conditions that further sinter the gel body into a glass overcladding tube.

Abstract: An optical element comprising an elongated channel for light travel comprising a light transmitting polymeric central core and further comprising multilayer particles, wherein a majority of the particles have both a longest dimension less than 1 micrometer and an aspect ratio of longest to smallest dimension of from 1000:1, to 10:1, wherein the particles are arranged in a concentration differential in at least a portion of a plane normal to the length of the channel so as to create a refractive index gradient in that plane.

Abstract: A microstructured fiber having a cladding comprising a number of elongated features that are arranged to provide concentric circular or polygonial regions surrounding the fibre core. The cladding comprises a plurality of concentric cladding regions, at least some of which comprising cladding features. Cladding regions comprising cladding features of a relatively low index type are arranged alternatingly with cladding regions of a relatively high index type. The cladding features are arranged in a non-periodic manner when viewed in a cross section of the fiber. The cladding enables waveguidance by photonic bandgap effects in the fiber core. An optical fiber of this type may be used for light guidance in hollow core fibers for high power transmission. The special cladding structure may also provide strong positive or negative dispersion of light guided through the fibre-making the fibre useful for telecommunication applications.

Abstract: An optical waveguide comprising cladding 1 and core segment 20 buried in cladding 1 and serving as a waveguide, wherein a combination of glass material constituting the core segment 20 and another glass material constituting the cladding 1 is so selected that an absolute value of difference in coefficient of thermal expansion between these materials (&agr;1−&agr;2) is within a range of 0 and 9×10−7/° C., where &agr;1 denotes a coefficient of thermal expansion of the former material and &agr;2 denotes that of the latter material.

Abstract: A wavelength tunable device for operating on at least a portion of energy propagating through a waveguide is disclosed. The wavelength tunable device includes an upper cladding and a lower cladding having a core substantially disposed there between and suitable for optically coupling to the waveguide, a pattern of nanostructures positioned substantially on the upper cladding distal to the core so as to define a reflectivity for energy propagating through the waveguide, and, a movable membrane aligned with the pattern of nanostructures so as to at least partially define a gap there between. This gap may be selectively controlled upon actuation of the movable membrane so as to cause a corresponding change in the reflectivity.

Abstract: A method for manufacturing an optical waveguide component with several layers stacked on a silicon substrate. The layers include a buffer layer, a first substrate, a guiding layer on the buffer layer and including an optical waveguide, and an outer layer as protection against external stresses. The layers are made from an organic-inorganic hybrid using a sol-gel process. An additional layer is disposed on the guiding layer so that a symmetrical structure is produced that has the same refractive index around the waveguide in the guiding layer.

Abstract: Electrically activated, wavelength-selective optical switches, a tunable wavelength selector, and a wavelength-tunable light modulator. In one preferred embodiment, an electrically activated, wavelength-selective optical switch comprises on a common substrate a first waveguide, a second waveguide comprising an electro-optic material, a set of Bragg gratings, and a means for generating an electrical field across the second waveguide. When the electrical field is applied, the refractive index of the electro-optic material and the Bragg phase-matching condition of the Bragg gratings are changed, causing one of the multiplexed input optical signals in the first waveguide to be guided by mode coupling into the second waveguide.

Abstract: The invention provides a waveguide comprising a channel 12 on an optical substrate 11, the refractive index of the channel being higher than that of the substrate. The waveguide includes at least one guide layer 13 arranged on the channel, the index of said guide layer being higher than that of the substrate. In addition, the channel 12 is integrated in the substrate 11. advantageously, the waveguide further includes a covering layer 14 deposited on the guide layer 13, the index of said covering layer being lower than that of the guide layer and lower than that of the channel. The invention also provides a method of fabricating the waveguide.