Abstract: The invention provides a variable optical attenuator or array with low PDL by using an embedded polymer channel waveguide with a plurality of resistive heaters fabricated on the top cladding of the polymer waveguide. The resistive heaters create a strong thermal gradient in the polymer layer stack which is associated with a strong refractive index gradient with the lowest refractive index under the heater. This refractive index gradient causes the optical mode in the channel to shift towards the buffer layer. Attenuation is induced by transition losses between heated and unheated regions in the polymer waveguide when an optical signal passes through these regions of the polymer waveguide.

Abstract: A variable optical attenuator is disclosed which comprises a plane-parallel birefringent element for separation/synthesis which separates light beams having orthogonal polarization directions on the same optical path, the birefringent element synthesizing light beams on different optical paths; a light converging lens disposed adjacent to the birefringent element for separation/synthesis; a reflecting mirror disposed at a focal point of the lens opposite to the birefringent element for separation/synthesis with respect to the lens; a variable polarization rotating device; and an input port and an output port which are disposed at the end of the birefringent element for separation/synthesis; the variable polarization rotating device being disposed at any position between the birefringent element for separation/synthesis and the reflecting mirror, the variable polarization rotating device controlling the rotational angle of the polarization direction of incident light beams from the input port, to thereby contr

Abstract: Apparatus controls optical coupling attenuation of an input optical beam to one of a plurality of output optical facilities. The apparatus includes a plurality of lenses, each lens aligned to couple a received optical beam to one of the plurality of output optical facilities and to couple the beam to a corresponding co-axially aligned output facility. Contiguous pairs of the plurality of lenses are arranged to have a predetermined space between such contiguous pairs, so that when the direction of a received beam is misaligned to a destination lens of a contiguous pair, only a first portion of the received beam gets coupled to the corresponding output facility of that destination lens and a second portion of the received beam propagates into the predetermined space so as not to be coupled to any of the plurality of output facilities.

Abstract: The present invention relates to an in-line fiber optic device including a housing and an opening extending through the housing defining an optical pathway, the pathway including an optically significant element for altering a signal transmitted through the pathway, and the device including a housing with a removable portion to permit access to the optical path. The present invention also relates to a fiber optic device with a housing defining an optical path with a first and second ferrule, the optical path including an optically significant element and a first end of the housing about an outer end of the first ferrule removable to permit access to the first end of the first ferrule. The present invention further relates to a system for altering the signal being transmitted through an optical fiber telecommunications connection. The present invention also relates to a method of providing an optically significant element in an optical fiber telecommunications assembly.

Abstract: An optical amplifying and relaying system capable of easily and highly accurately monitor troubles in optical amplifiers provided in an up and a down optical fiber transmission line opposing each other is disclosed. Monitoring light signal folding-back lines including variable optical attenuators 4a and 4b and wavelength selective reflecting means 5a and 5b, respectively, are provided between optical transmission lines L1 and L2, which oppose each other and on which optical amplifiers 4a and 4b are disposed each other.

Abstract: An optical attenuator having a multi-mode waveguide segment and a perturbation element. An incident single-mode optical signal is converted to a multi-mode optical signal in the multi-mode waveguide segment. The optical attenuator couples incident light into higher order modes of the multi-mode waveguide segment resulting in attenuation of the incident optical signal.

Abstract: In one embodiment of the invention, an optical attenuation device has an input/output 6 on which a multiplexed optical input stream is received. A multiplexer/de-multiplexer (MUX/DEMUX) 2 separates the received stream into individual optical signals on individual channels and has an output/return path 12 from the MUX/DEMUX 2 for each of the channels. Reflector means 4 in each output/return path 12 reflects all or a proportion of the optical signal on the respective channel back along the output/return path 12 to the MUX/DEMUX 2. At the MUX/DEMUX, the optical signals are combined into a multiplexed stream which is output on the input/output 6. In an alternative embodiment, the device has first and second MUX/DEMUX 2, 20, an output path 12 from the first MUX/DEMUX 2, attenuation means 40 at the end of each output path 12 and return paths 120 from the attenuation means 40 to the second MUX/DEMUX 20.

Abstract: The present invention provides a waveguide, a method of manufacture therefore, and an optical communications system including an optical device comprising the waveguide. The waveguide may comprise a substrate, a planar waveguide core located over the substrate and a cladding layer located adjacent the planar waveguide core, the cladding layer comprising a silsesquioxane oligomer.

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 variable attenuator assembly (1) includes a variable attenuating connector (VAC) (11), a coupling sleeve (12), and a second plug-type connector (13). The VAC includes a housing (20) and an attached double screw mechanism (110). The double screw mechanism is finely adjustable because it uses an adjusting knob (40) having an external thread (401) and an internal thread (402) with different screw pitches. The external thread engages with an internally threaded bore (303) of a connecting nut (30) attached to the housing. The internal thread engages with outer threading (602) on a ferrule holder (60) received in the adjusting knob. When the adjusting knob is rotated, the knob moves in one direction, and the ferrule holder is moved in the opposite direction, the total distance of ferrule holder movement relative to the housing being proportional to the difference between the screw pitches.

Abstract: A device for variable attenuation of an optical channel includes an elongated core surrounded by a cladding. Optical energy propagating along the longitudinal axis of the core is normally confined thereto by the difference in refractive indices between the core and cladding. The thermo-optic coefficients of the core and cladding are closely matched such that waveguide confinement is substantially invariant with respect to ambient temperature. The device further includes a thermal source arranged above the core. The thermal source is operable to generate a temperature gradient of controllable magnitude along a vertical axis extending through the core. The temperature gradient causes reduction of the local refractive index within the core relative to surrounding regions of the cladding such that a portion of the optical energy is deflected away from the thermal source and extracted from the core.

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: An equalizer is disclosed. The equalizer includes a light distributor configured to distribute light signals received through an inlet side across an outlet side. Each of the light signals is associated with a different wavelength. The equalizer also includes optics configured to cause different light signals to separate as the light signals travel through the light distributor. The equalizer also includes a plurality of attenuators configured to attenuate the light signals in a region of the light distributor where the light signals are separated from one another.

Abstract: An optical device includes a ridge waveguide defined by a ridge extending from a slab of a light transmitting medium. The optical device also includes trenches extending into the slab of light transmitting medium on opposing sides of the ridge. At least one of the trenches is associated with a trench displacement that tapers from a first displacement to a second displacement. The trench displacement is the distance between the ridge and the side of a trench closest to the ridge. The optical device also includes at least one electrical contact positioned in at least one of the trenches.

Abstract: A variable-wavelength light source unit for sending output light of an arbitrary wavelength selected in a variable-wavelength light source section 1 has an optical variable attenuator 2 placed on the output side of the variable-wavelength light source section and a control circuit 4 for controlling the attenuation amount of the optical variable attenuator in response to light output provided by splitting a part of the output light.

Abstract: An optical apparatus for transmitting an optical signal includes a static filter, a Faraday rotator and a reflector. The Faraday rotator makes a first change in polarization of an optical signal in a first direction, and a second change in polarization of the optical signal received from the reflector in a second direction. This produces a polarization of the optical signal that is substantially orthogonal to an initial polarization state of the optical signal.

Abstract: An optical network, an optical device, and one or more MEMS optical components are disclosed. The optical network comprises one or more optical input sources, one or more optical output collectors, and the optical device. The optical device is optically coupled between the one or more optical input sources and the one or more optical output collectors. The optical device is formed on a intergrated MEMS chip. The optical device comprises the one or more MEMS optical components formed on the integrated MEMS chip. In fact, each MEMS optical component may be monolithically fabricated on, self assemblable on, and reconfigurable or moveable on the integrated MEMS chip.

Abstract: Novel light switches and attenuators are disclosed. In one form of the invention, a novel 1×2 switch is formed by positioning a moveable cantilever mirror having an opening intermediate three fiberoptic lines. In another form of the invention, a novel n×n switch is formed by positioning a moveable cantilever mirror having n openings intermediate n sets of three fiberoptic lines. In still another form of the invention, a novel variable optical attenuator is formed by incrementally positioning a moveable cantilever mirror having an opening intermediate a set of three fiberoptic lines.

Abstract: An optical amplifying and relaying system capable of easily and highly accurately monitor troubles in optical amplifiers provided in an up and a down optical fiber transmission line opposing each other is disclosed. Monitoring light signal folding-back lines including variable optical attenuators 4a and 4b and wavelength selective reflecting means 5a and 5b, respectively, are provided between optical transmission lines L1 and L2, which oppose each other and on which optical amplifiers 4a and 4b are disposed each other.

Abstract: A method and apparatus are provided for transmitting an optical communications signal. The method includes the steps of securing an optical device onto an optically transparent substrate with an optically transparent adhesive such that an axis of transmission of the optical device passes directly through the optically transparent adhesive and a portion of the body of the optically transparent substrate, darkening a portion of the optically transparent adhesive with a laser; and transmitting light from the optical device through the darkened portion of the optically transparent adhesive such that at least some of the light from the optical device is absorbed by the darkened portion.

Abstract: Disclosed is a MEMS variable optical attenuator. The MEMS variable optical attenuator comprises a substrate having a flat upper surface; optical transmitting and receiving terminals arranged on the upper surface of the substrate; a movable optical waveguide arranged at a location such that it attenuates the maximum amount of light transmitted between the optical transmitting and receiving terminals; a micro actuator arranged on the substrate for moving the movable optical waveguide; and a voltage supply unit for supplying driving voltage to the micro actuator, wherein the micro actuator moves the movable optical waveguide so that the light attenuation amount is decreased in accordance with the increase in the driving voltage supplied from the voltage supply unit.

Abstract: A fiber optic attenuating element is formed of a thermoplastic polymer having (i) a refractive index in the range of between about 1.42 and 1.47 as measured at a temperature of 230° C. and a wavelength of 1550 nm, (ii) a glass transition temperature of at least 105° C., and (iii) an intrinsic loss of less than one dB/mm at 1310 and 1550 nm. In disclosed embodiments, the polymer includes at least one monomer including fluorinated moieties and, optionally, one or more additional monomers. A main body portion of the element has a first planar contact face on a first side and a second planar contact face on a second, opposite side. The contact faces are dimensioned to couple optically with first and second optical fibers when ends of the fibers are urged against the faces by parts of an attenuator device in which the element is mounted.

Abstract: An electrical variable optical attenuator (10) of the present invention has a housing (1), a cover (2), an attenuating means (3), an optical module (4), an electrical driving element (5), an input fiber (87) and an output fiber (86). The attenuating means includes a carrier (30) having a guide groove (301) and an inner screw (302). A filter (32) is fixed on the carrier. The optical module includes a guide pole (41). The electrical driving element has a screw rod (552), which couples with the inner screw. The attenuating means is assembled inside the optical module with the guide pole being received in the guide groove to confine the direction of movement of the carrier along the screw rod, thus helping to avoid trembling of the filter when the screw rod is rotated.

Abstract: The object of the present invention is to provide a highly reliable optical fixed attenuator and the manufacturing process thereof being free of the conventional cumbersome processes including the process for inserting the optical fiber into the ferrule and fixing thereto. In the present invention, the surface of an optical fiber is metalized to serve as an electrode of the electroforming process so that a metal layer to serve as the ferrule 11 is directly formed over the outside surface of the optical fiber 10, and, as a result, a long ferrule, wherein the optical fiber 10 and the metal layer are fully integrated, is made available, whereby an optical device to constitute the desired optical fixed attenuator can be obtained by simply cutting such a long ferrule to any desired length.

Abstract: Cholesteric liquid crystal cell units are used for reflecting or transmitting incident light responsive to control signals. A cholesteric liquid crystal cell unit has a first cholesteric liquid crystal cell and a second cholesteric liquid crystal cell. The second cholesteric liquid crystal cell respectively reflects or transmit lights from the first cholesteric liquid crystal cell responsive to a control signal when the first cholesteric liquid crystal cell reflects circularly polarized light of one state or transmits the incident light. In one embodiment of the cell unit, a &pgr;-phase waveplate element is located between the first and second cholesteric liquid crystal cells. With the cholesteric liquid crystal cell units, devices such as optical switches, and WDM add/drop multiplexers, and optical switch systems with arrays of input and output optical fibers between a switching matrix formed by the cholesteric liquid crystal cell units, may be constructed.

Abstract: A beam splitter wave guide apparatus and method for enabling the selection of one of a plurality of distinct spectra of an optical input signal and for enabling an intensity of a resulting output signal to be adjusted. The apparatus comprises a cylindrical optical element having an input end and an output end. The input end includes a pair of spaced apart surfaces that each include a suitable filter formed thereon. A first one of the filters passes a first spectrum of light and reflects all other light outside the first spectrum. The second filter passes a second spectrum of light but reflects all other light outside of the second spectrum. Rotating the cylindrical optical element allows either the first or second spectrum to be selected such that an optical output signal is generated having the desired spectrum. Controlled rotational movement of the cylindrical optical element further allows the intensity of the resulting optical output signal to be varied as needed.

Abstract: A reflection-type variable optical attenuator comprises: a main attenuator unit including a first birefringent crystal plate, a Faraday rotational angle varying unit, and a second birefringent crystal plate arranged in this order; an input port and an output port that are arranged on a side of one end of the main attenuator unit; and a two-point reflection-type optical path varying reflector that is arranged on a side of the other end of the main attenuator unit. Light that comes in from the input port makes a round trip in the main attenuator unit and goes out through the output port.

Abstract: An optical device including dynamic channel equalization is provided. In an exemplary multiplexer or line amplifier configuration the device includes a plurality of separate optical paths, each of which receiving a separate group of optical signals. Each group of optical signals is provided to an associated variable optical attenuator. Separate inputs of an optical combiner are each coupled to an output of an associated one of the variable optical attenuators. The optical combiner has an output providing the separate groups of optical signals in an aggregated form on an aggregate optical signal path. An optical performance monitor is coupled to the aggregate optical signal path, and is configured to detect an optical signal to noise ratio of each of the separate groups. The monitor supplied a feedback signal to corresponding ones of the variable optical attenuators for adjusting a respective attenuation associated with each of the attenuators in dependence of the detected optical signal to noise ratios.

Abstract: The invention provides a planar lightwave circuit type variable optical attenuator in which a small PDL is maintained even when an attenuation is large. The variable optical attenuator is constituted by a Mach-Zehnder interferometer comprising a substrate, two optical waveguide arms buried in a clad formed on the substrate, and thin-film heaters disposed on the surface of the clad and adjusting optical lengths of the optical waveguide arms. The optical waveguide arms are each made of a silica-based glass material, and a difference &Dgr;L0 between arm lengths is set to be in the range of 0.38 &mgr;m to 0.52 &mgr;m.

Abstract: A variable optical attenuator has a first waveguide and a second waveguide that are optically coupled together. At least one of the waveguides has a movable cantilever portion that is movable relative to the other to control attenuation of an optical signal traveling between the two. Preferably, electrically driven actuators deflect the movable waveguides to a relative position at which a desired optical attenuation value is achieved. Each movable waveguide may deflect in an opposite direction to the other waveguide. The electrically driven actuator receives a drive signal that controls the amount of deflection. The electrically driven actuator may be an electrostatic, electrothermic, or electromagnetic actuator. In the example of an electrostatic actuator, one electrode may be disposed on a movable waveguide and another adjacent the moveable waveguide to create the electrostatic force that moves the waveguide.

Abstract: An electrically variable optical attenuator and associated methods are disclosed. In one aspect, the attenuator includes at least one sensor that provides a sensor output with respect to a variable that affects attenuation. Methods of characterizing the attenuator include obtaining a set of attenuation/sensed variable data, and generating a relationship (such as a look-up table or mathematical function) relating the sensed variable to the attenuation. Aspects of the invention also include characterizing the control input/attenuation output to be related by a selected mathematical function.

Abstract: Disclosed is a MEMS (Micro Electro Mechanical System) variable optical attenuator. The MEMS variable optical attenuator comprises a substrate having a flat upper surface; an electrostatic attenuator disposed on the upper surface of the substrate; transmitting and receiving terminals disposed on the substrate so that optical axes of the terminals coincide with each other; and a beam shutter moved to a designated position between the transmitting and receiving terminals by the actuator, wherein the beam shutter is provided with a first coating layer made of a material with a reflectivity of more than 90% and formed on a surface of the beam shutter, and a second coating layer made of a material with a reflectivity of less than 80% so that a part of light is transmitted by the second coating layer and with a photodisintegration rate of the transmitted light determined by a thickness of the second coating layer.

Abstract: A method for operating a planar lightwave circuit at a constant power consumption, comprises providing a matrix of integrated active elements, heating independently each active element with a separate heating power, and cooperatively operating the heating powers of the active elements to keep a sum of the operating heating powers constant in time independently on the dynamic operation of the element. The active element has two connecting configurations and is operative to have a phase change in a light beam passing through each of the connecting configurations, both connecting configurations being constantly heated. The active element is operable in both analog and digital modes with a constant power consumption.

Abstract: A motor driven variable optical attenuator (10) comprises a base (12), a cover (13), an attenuation device (11), and a motor (19). The attenuation device comprises a fixed collimator (111), a movable collimator (112) retained in a holding device (113), and an adjusting device. The two collimators are aligned end-to-end. The adjusting device comprises a first screw rod (114), and a second screw rod (115). The first screw rod comprises a thread portion (1141) rotatably engaged in the holding device, and a gear (1142). The second screw rod comprises a thread portion (1151), and a head (1152). The thread portion of the second screw rod meshes with the gear of the first screw rod. The motor comprises a cylindrical projection (195) engaged in the head of the second screw rod. The motor rotates the second screw rod, which drives the first screw rod, which laterally moves the holding device.

Abstract: A waveguide includes a waveguide core that has a bottom surface and a top surface that defines an angle. The waveguide also includes a cladding layer adjacent to the bottom surface. The cladding layer has a thickness equal to or greater than an evanescent tail of a mode to be transmitted along the wave guide core.

Abstract: A fiber optic cable suitable for blowing into and through ducts containing pressurized gas, such as natural gas, has the fibers therein arranged in arrays that form longitudinally extending vents. The vents are blocked from transmission of any gas by each being filled with a compliant member which assumes the cross-sectional shape of the vents thereby blocking it. In a second embodiment of the invention, the first and third ferrules are fixed within the housing with their offset bores in alignment. A second ferrule is interposed between the first and third ferrules and is mounted in a rotatable member for misaligning the bore in the second ferrule with the bores in the first and third ferrule to produce attenuation of a signal passing through the ferrules by misaligning the fibers contained in the bores.

Abstract: A modular optical platform for selective wavelength switching that can be adapted to perform various other functions, such as dynamic gain equalization (DGE) and add/drop multiplexing (ADM) provides the versatility and modularity that will be essential to the future of the fiber optics industry. The basic platform includes a first lens for directing an optical signal, a diffraction grating for dispersing an optical signal into its component wavelength channels, a second lens for directing the component wavelength channels, and a modifying device for conducting one or more of a variety of functions including switching, DGE and ADM. The first and second lens are preferably replaced by a single concave reflective mirror having optical power.

Abstract: A method of controllably attenuating a beam of light coupled into a port includes directing the beam of light against a mirror, and controlling an orientation of the mirror such that a predetermined fraction of the beam of light is coupled into the port. The predetermined fraction is less than a maximum fraction corresponding to optimal coupling of the beam of light into the port. The method may be implemented with a variable optical attenuator including a first port, a second port, a mirror located to direct light output by the first port to the second port, and a controller coupled to the mirror to align it such that the predetermined fraction of light is coupled into the second port. The method may also be implemented with an optical switch.

Abstract: A first waveguide holding member has a first transverse surface region and a first optical waveguide having an end terminating at the first transverse surface region. A second waveguide holding member has a second transverse surface region which confronts the first transverse surface region of the first waveguide holding member and a second optical waveguide having an end terminating at the second transverse surface region. A guide member is operatively coupled to the first and second waveguide holding members and guides the first waveguide holding member in a transverse direction relative to the second waveguide holding member so as to selectively optically couple and decouple the ends of the first and second optical waveguides.

Abstract: An optical attenuator has a planar MEMS substrate supporting two optical fibers; an actuator; and a silicon vane actuatable by said actuator for a movement into and out of the optical beam passed between the fibers. The vane is configured to divert at least a portion of the optical beam off the optical axis when the element is moved into the optical beam. The vane has at least one surface disposed non-perpendicularly relative to the optical axis of the beam. The vane may be of a wedged shape.

Abstract: A saturable optical absorber component is made of an inhomogeneous absorption material including a plurality of sets of quantum boxes formed in stacked layers. The sizes of the quantum boxes of each set define an absorption wavelength associated with the set.

Abstract: An array antenna apparatus for producing a time-delay beamformed RF signal includes a laser, a modulator for RF modulating the laser optical signal, a first plurality of optical paths coupling the modulator output to a dispersive prism, another plurality of optical paths coupling the dispersive prism outputs to a corresponding plurality of time delay trimmers, an attenuator coupled to each time delay trimmer, and an optical switching matrix to which the time delay trimmers outputs are input. The inputs to the optical switching matrix accordingly are time and amplitude adjusted to remove front end errors prior to rerouting. This is repeated in the back end of the apparatus, in which the switching matrix outputs are each applied to a corresponding attenuator, the outputs of which are then each applied to a photodetector to generate a plurality of replica RF signals that are each applied to a time shifter, thereby producing an error-corrected output that is then applied to an antenna array.

Abstract: A variable attenuator has first and second substantially identical ferrules or capillaries, each being mounted in a barrel or splice housing and extending toward each other, with their distal ends being separated by a gap of a first width. The width of the gap is controlled by a sleeve into which the ferrules are inserted, the ends of the sleeve butting against the front faces of the barrels. The ferrules are made by producing a glass rod mounted between the barrels and having a bore offset from and parallel to the centerline of the rod and breaking or cleaving the rod at its longitudinal center. The broken ends are then polished. The barrels are keyed to a housing member so that the offset bores are coincident in the zero position as defined by the keys.

Abstract: An electrical variable optical attenuator (10) includes a housing, an attenuating device (3), an optical module (4), and an electrical controlling unit (5). The housing encases the attenuating device, optical module and electrical controlling unit. The electrical controlling unit includes an electrical resistor (57), a terminal holder (56), and a stepping motor (55). The terminal holder includes a plurality of terminals (562), and a plurality of terminal sleeves (563) depending from an insulating plate (561). The terminal holders are fittingly received in positioning holes (131) defined in the housing, so that the terminals can electrically connect the stepping motor and the electrical resistor with an external power supply. The insulating plate is made of rubber, which is softer than a material of the housing. A diameter of the terminal sleeves is slightly greater than a diameter of the positioning holes. Thus the terminal sleeves provide an airtight and watertight seal.

Abstract: A method of measuring a power spectrum of an optical signal. The optical signal is transmitted through an optical fiber. A power of at least one wavelength of the optical signal is coupled from a first mode to a second mode of the waveguide. The power of the optical signal coupled from the first mode to the second mode is measured at a detector.

Abstract: Disclosed is an optical waveguide fiber preform and an optical waveguide fiber drawn therefrom, in which the density and thus the effective refractive index of the clad layer is caused to change in a pre-selected way axially along the waveguide preform and the associated waveguide fiber. The axial change in density of the clad layer is due to the fraction of the clad volume that is air or a glass of a composition different from that of the base clad glass. The axially variation in clad index changes the signal mode power distribution, thereby changing key waveguide fiber parameters such as magnitude and sign of dispersion, cut off wavelength and zero dispersion wavelength. The invention includes methods of making the structures having an axially varying clad layer. The invention relates to preforms and associated waveguide fibers which guide light due to difference in refractive index between core and clad.

Abstract: An optical variable attenuator is provided including polarizers for extracting a predetermined polarized wave component from an input optical signal, an array of Faraday rotators formed of a ferromagnetic material and arranged in series for rotating the plane of polarization of the input signal, electromagnetic coils for supplying magnetic fields to the Faraday rotators, and current supply control circuits for setting the polarization-rotating angle of the array by controlling the intensity of the magnetic fields supplied to the Faraday rotators. The polarization-rotation angle of the array can be finely adjusted and maintained, even when the magnetic fields are not continuously supplied to the Faraday rotators.

Abstract: The optical component includes an array of array waveguides. The optical component also includes a first light distributing component configured to distribute a first light signal to the array waveguide. The first light signal is distributed such that a fraction of the first light signal enters each array waveguide as a light signal fraction. The optical component also includes a second light distribution component configured to received the light signal fractions from the array waveguides. The light signal fractions are received so they combine to from a second light signal with a periodic intensity distribution.

Abstract: The invention relates to an optical device comprising an emitting source and a partly-reflective element which is adapted for receiving an emitted light beam. This element is tilted in a small angle with respect to the emitted light beam. A portion of the emitted light beam is reflected by the partly-reflective element towards a transmittive element which is arranged in close proximity to the emitting source and adapted to receive and transmit the reflect portion. The transmittive element is arranged for at least partly fixing or positioning an optical fiber, which is emitting the input light beam, and provided for transmitting the laterally offset reflected portion of the input light beam away from the input fiber.

Abstract: The invention features the drawbridge assembly and its applications in optical switches, optical crossconnects, optical add/drop multiplexers and variable optical attenuators. In optical switches and optical crossconnects, an array of the drawbridge assemblies can be used to redirect the multiple input lights to multiple outputs. In add/drop multiplexers, the drawbridge assemblies can select the light channels to be added and dropped. In the attenuator embodiment, a vertical mirror is inserted into two fibers, the first one as the input and the second one as output. The drawbridge assembly controls the position of the vertical mirror for blocking a certain portion of the light and enabling the attenuation. The continuous change of the mirror position results in variable attenuation. A series of VOA form a multi-channel VOA system on a single substrate.