Abstract: Provided is an apparatus and method for use thereof. The apparatus, in one embodiment, includes first and second 1×N couplers integrated on a substrate and configured to receive an optical symbol having an intended time slot, N being at least three. The apparatus, in this embodiment, further includes N waveguide arms integrated on the substrate, having modulators and coupled between the first and second 1×N couplers. The apparatus, in this embodiment, additionally, includes a modulator controller configured to drive the modulators such that, following transmission over a distance, components of the optical symbol outside of the intended time slot are attenuated relative to components within the intended time slot.

Abstract: An attenuator connector comprising a housing having a front and rear orientation, a ferrule disposed in the housing, a clamping assembly disposed in the housing rearward of the ferrule and adapted to receive and retain a terminating fiber and a stub of attenuating fiber disposed in the ferrule.

Abstract: A receiver includes a waveguide defined in a layer of silicon positioned on a base. The waveguide is immobilized relative to the base along the length of the waveguide. The waveguide is unbranched and is a multi-mode waveguide. The receiver also includes a groove configured to receive an optical fiber. The groove is positioned such that when the optical fiber is positioned in the groove the waveguide receives a light signal that exits a facet of the optical fiber. The receiver also includes a light sensor configured to receive the light signal from the waveguide after the light signal is received by the waveguide, is guided through the waveguide, and exits the waveguide. The receiver also includes a tunable optical attenuator configured to attenuate the light signal as the light signal travels along the waveguide. The receiver can be formed on a chip such that the waveguide is the only optical waveguide on the chip.

Abstract: It is to provide an optical element, an optical module holder including the optical element, an optical module, and an optical connector that can attenuate with high accuracy an amount of light coupled between an optical transmission line and a photonic element using light refraction, thereby realizing appropriate optical communication while reducing manufacturing costs. A light attenuating refractive surface 7 is formed on an optical surface 4 disposed on an optical path between an optical transmission line 2 and a photonic element 3 in a main body of the optical element. The light attenuating refractive surface 7 attenuates the amount of light coupled between the optical transmission line 2 and the photonic element 3 by refracting and deflecting incident light.

Abstract: The present invention discloses an interferometer optical switch that can carry out switching over a broad band and has a high extinction ratio and large fabrication tolerance. The interferometer optical switch employs a phase generating coupler, the phase difference of the output of which has wavelength dependence, as at least one of the optical multi/demultiplexing device included in the interferometer optical switch. A wavelength insensitive interferometer optical switch is implemented by making the sum 2?{?1(?)+??L(?)+?2(?)} constant regardless of the wavelength, where ?1(?) is the phase produced by the first optical multi/demultiplexing device, 2???L(?) is the phase difference of the optical delay line with an optical path length difference of ?L, and 2??2(?) is the phase produced by the second optical multi/demultiplexing device.

Abstract: In one general embodiment, a method for deflecting an optical signal input into a waveguide is provided. In operation, an optical input signal is propagated through a waveguide. Additionally, an optical control signal is applied to a mask positioned relative to the waveguide such that the application of the optical control signal to the mask is used to influence the optical input signal propagating in the waveguide. Furthermore, the deflected optical input signal output from the waveguide is detected in parallel on an array of detectors. In another general embodiment, a beam deflecting structure is provided for deflecting an optical signal input into a waveguide, the structure comprising at least one wave guiding layer for guiding an optical input signal and at least one masking layer including a pattern configured to influence characteristics of a material of the guiding layer when an optical control signal is passed through the masking layer in a direction of the guiding layer.

Abstract: In an optical attenuator, there are a first optical waveguide 3A connected to an input optical waveguide 1, a second optical waveguide 3B connected to an output optical waveguide 2 and a connecting optical waveguide 4, which are connected with each other in series. A first recess 13A and a second recess 13B are formed in a positional relationship of opposite directions with respect to an axial direction of an optic axis of light that is inputted through the input optical waveguide 1, transmitted through the first optical waveguide 3A, the connecting optical waveguide 4 and the second optical waveguide 3B and outputted from the output optical waveguide 2.

Abstract: A fiber intensity reducer comprises a guided system fiber including a core and an outer cladding layer, an unguided fiber intensity reducing (FIR) section including a first fiber “end cap fiber” having a first end and a second end attached at its first end to the system fiber. A bond region is between the first end of the first fiber and the system fiber. The FIR section provides a softening point of at least 700° C. throughout and provides a sufficient transverse dimension along its entire length so that a beam of radiation received from the system fiber expanding therein avoids an interface with the air along its entire length. In one arrangement, the FIR section includes an outer capillary on the end cap fiber, wherein the capillary and the end cap fiber provide refractive index matching.

Abstract: A waveguide receiving light which propagates through free space is configured with a coupler and delivery fiber. The coupler, including a GREEN or multimode fiber, has a protective coating and so does the delivery fiber. Upon splicing of the coupler to the delivery fiber, the protective coatings of the respective coupler and delivery fiber are spaced apart exposing thus end regions of the respective coupler and fiber. The exposed regions are covered by a light stripper made of material having a refractive index which is substantially the same as or greater than that one of outer claddings. Accordingly, the light stripper minimizes the amount of light capable of coupling into the protective coatings of the respective delivery and coupler fibers enhancing thus a power handling capabilities of the waveguide.

Abstract: A tilting mirror MEMS variable optical attenuator attenuates light over a band of wavelengths with minimum wavelength dependent loss. The attenuator includes a lens that has a wedged input face and is made from a material that has high dispersion. The lens design causes different wavelengths to travel different paths through the attenuator such that wavelength dependent loss is reduced. The attenuator may be designed to have minimum wavelength dependent loss at a specified attenuation greater than zero.

Abstract: A method may include bending a first optical fiber of a plurality of optical fibers; measuring light leaked from the first optical fiber with a photo detector; robotically moving the photo detector to a second optical fiber of the plurality of optical fibers; bending the second optical fiber; and measuring light leaked from the second other optical fiber with the photo detector.

Abstract: In the manufacture of an optical attenuator having a desired value of the optical loss end regions of two optical fibers are placed with an offset in the traverse direction in relation to each other and having their end surface at each other. Thereafter the region at end surfaces is heated to make the ends melt to each other and the heating is then further continued. To achieve the desired loss in the finished attenuating splice the further heating is stopped for an optical loss exceeding the desired loss by a calculated value. This value can be obtained from measurements in real time of the loss for the splice during the continued heating. The measurements can be made at the beginning and end of an interrupt of the further heating. An attenuator manufactured in this way obtains an attenuation that accurately agrees with the desired value.

Abstract: Disclosed is an optical transmission device with a simple configuration that can attenuate an input optical power only when it is necessary so that it falls within a predetermined range, and can suppress insertion loss when it is unnecessary. A variable optical attenuator is configured pluggable. A pluggable variable optical attenuator is equipped with an optical connector that is an interface of an optical signal and an electrical signal connector for receiving an electrical signal that specifies the amount of control used for feedback-controlling the attenuation, and controls the attenuation depending on the input optical power of the optical transmission board. Moreover, an optical through that has the same shape as the variable optical attenuator being configured pluggable and that is configured pluggable is prepared.

Abstract: An optical transmission apparatus including a variable optical attenuator is provided. The optical transmission apparatus includes a module detection portion for detecting a type of module that receives light attenuated by the variable optical attenuator; and a variable optical attenuator control portion for controlling so as to change control parameters of the variable optical attenuator in accordance with the type of module detected by the module detection portion.

Abstract: An optical transmission fiber including a core having a first index of refraction, a cladding material located around the core and having a second index of refraction less than the first index of refraction, a first coating material located around a first portion of the cladding material and having a third index of refraction greater than the second index of refraction, and a second coating material located around a second portion of the cladding material and having a fourth index of refraction less than the second index of refraction.

Abstract: An optical transmission device includes: an attenuator that attenuates an optical signal before being input into an optical element by a predetermined attenuation amount determined so that a level of an adjustment optical signal input into the optical element falls within a predetermined dynamic range of the optical element; and a controller that adjusts the predetermined attenuation amount so that a level of the optical signal input into the optical element falls within the predetermined dynamic range.

Abstract: A variable optical attenuator for adjusting a power of light which is output from an output end of a first optical fiber and is to be led to an input end of a second optical fiber, includes a reflection member which reflects the light output from the output end of the first optical fiber, a density filter which transmits the light reflected from the reflection member and controls the power of the light which is transmitted by the density filter depending on a light-transmitting position on the density filter, and an optical member which reflects the light transmitted by the density filter to lead the light to the reflection member. The reflection member is disposed tiltably, the power of the light transmitted by the density filter attenuates along a direction in which the light-transmitting position is changed, and the light-transmitting position of the light is changed by tilting the reflection member.

Abstract: An optical transmission system which provides bandwidth restricted optical signal comprises an input terminal (10) for accepting an electrical binary signal, an amplifier (12) for amplifying said electrical binary signal to the level requested for operating an electrical-optical converter (16) such as a Mach Zehnder light modulator, a bandwidth restriction means (14) which is for instance a low pass filter for restricting bandwidth of said electrical binary signal, and an electrical-optical conversion means (16) such as a Mach Zehnder light modulator for converting electrical signal to optical signal. Because of the location of the low pass filter (14) between an output of the amplifier (12) and the Mach Zehnder light modulator (16), the amplifier (12) may operate in saturation region to provide high level output signal enough for operating the Mach Zehnder light modulator, and a signal shaped by the low pass filter (14) is applied to the Mach Zehnder light modulator (16) with excellent waveform.

Abstract: An airline (AL) optical fiber (“AL fiber”) that has an AL region with airlines, with the AL region arranged relative to the fiber core so as to make the fiber bend insensitive. The AL region is capable of supporting one or more higher-order optical modes. One method of reducing multipath interference (MPI) includes accessing a section of the AL fiber and closing at least one of the airlines in the section. This serves to attenuate one or more higher-order modes, which reduces MPI. In one example, the AL fiber has an end section wherein the airlines are filled with a blocking material. An example blocking material is a curable adhesive that is wicked into the airlines via capillary action and then cured when the adhesive reaches a certain depth from the fiber end. In another example, the blocking material is formed by heating the AL fiber section to cause the section to melt and block the airlines, so that the melted AL fiber serves as the blocking material.

Abstract: Control of attenuators used to regulate optical signals is disclosed. An assembly including an IR source and an IR sensor is provided to sense blockage of optical signals transmitted between two collimators via a fixed common light blocker that is driven by a motor. The motor is controlled to make sure that that the reset of the light blocker is properly done in an event in which a power supply is intentionally or incidentally cut off. An auxiliary power supply is provided to energize other parts in an attenuator should power supply is intentionally or incidentally cut off.

Abstract: In an optical attenuator, there are a first optical waveguide 3A connected to an input optical waveguide 1, a second optical waveguide 3B connected to an output optical waveguide 2 and a connecting optical waveguide 4, which are connected with each other in series. A first recess 13A and a second recess 13B are formed in a positional relationship of opposite directions with respect to an axial direction of an optic axis of light that is inputted through the input optical waveguide 1, transmitted through the first optical waveguide 3A, the connecting optical waveguide 4 and the second optical waveguide 3B and outputted from the output optical waveguide 2.

Abstract: A variable optical attenuator with photoelectric detector, comprising a collimator, a variable optical attenuator chip, wherein the variable optical attenuator further comprises a photoelectric detector; and the photoelectric detector receives and detects partial light from the variable optical attenuator chip. The variable optical attenuator of the invention is capable of detecting attenuation change of itself via the variable optical attenuator chip. Thus, real-time monitoring and feedback are implemented, and the attenuation performance of the variable optical attenuator is improved.

Abstract: Attenuators used to regulate optical signals are disclosed. According to one aspect of the present invention, an assembly including an IR source and an IR sensor is provided to sense blockage of optical signals transmitted between two collimators via a fixed common light blocker. The movement of the light blocker is sensed by a sensing assembly including an IR source and IR sensor. By detecting the photocurrent from the IR sensor and a feedback circuit, the attenuation of the optical signals can be well controlled.

Abstract: An ophthalmic endoilluminator includes a light source, a variable-wedge rotating-disk attenuator, a condensing lens, and an optical fiber. The variable-wedge rotating-disk attenuator attenuates the light produced by the light source. The variable-wedge rotating-disk attenuator includes a wedge capable of being adjusted over a variable angle as measured through an arc of the wedge and an axle to which the wedge is attached. The axle rotates such that the wedge rotates around a pivot defined by the axle. The condensing lens focuses the attenuated light. The optical fiber carries the focused light into an eye. The variable-wedge rotating-disk attenuator is located such that it affects the intensity of a light beam transmitted into an eye.

Abstract: A multiple dwelling unit (MDU) optical fiber splitting unit (FBU). One or more fiber strands enters the FBU at the MDU. Each strand may be connected to a variable attenuator. Each strand is subject to a one to four split. Each of the four split fibers is connected to an optical connection interface such as an SC/ACP connector. Each optical output is connected to an MDU-ONT that supplies an optical interface to copper and cable infrastructure, enabling fiber-based services to be provided to units in an MDU with reduced installation costs and utilization of existing twisted pair and coaxial distribution lines.

Abstract: In one general embodiment, a method for deflecting an optical signal input into a waveguide is provided. In operation, an optical input signal is propagated through a waveguide. Additionally, an optical control signal is applied to a mask positioned relative to the waveguide such that the application of the optical control signal to the mask is used to influence the optical input signal propagating in the waveguide. Furthermore, the deflected optical input signal output from the waveguide is detected in parallel on an array of detectors. In another general embodiment, a beam deflecting structure is provided for deflecting an optical signal input into a waveguide, the structure comprising at least one wave guiding layer for guiding an optical input signal and at least one masking layer including a pattern configured to influence characteristics of a material of the guiding layer when an optical control signal is passed through the masking layer in a direction of the guiding layer.

Abstract: A variable optical attenuator is disclosed, which attenuates a beam of light while preserving its polarization substantially independent of wavelength. The beam of light is attenuated by a filter patterned with a grating of blocking stripes with serrated edges, which partially block and partially transmit the beam of light, respectively. The serrated edges provide for low polarization dependent loss. Along a length of the filter, a mark to space ratio of blocking stripe and aperture widths increases. By a linear translation of the filter along its length attenuation can be varied to a desired value. A stepper motor with lead screw can provide a suitable linear translation to give the filter a latching property.

Abstract: A system is provided for characterizing optical fibers carrying signal traffic. The system includes a transmitter, a variable optical attenuator (VOA), a receiver, and a computing device. The transmitter propagates an optical test signal along a channel of a fiber pathway. The VOA adjusts the attenuation of the optical test signal from an initial, greater attenuation to a subsequent, lesser attenuation. At the same time, the computing device monitors at least one other channel of the fiber pathway and identifies effects upon the other channel(s) from the optical test signal. The computing device may communicate with the VOA and with other components of the fiber pathway to direct adjustment of the signal strength. A maximum optical test signal strength may thus be achieved that does not negatively affect signal traffic on the other channels, and the fiber pathway may subsequently be tested using the achieved maximum optical test signal strength.

Abstract: The invention relates to a method and a device for coupling fiber optic cables. Said device comprises at least one module, which is equipped with at least one retaining unit for retaining at least two cassettes. The invention is characterized in that: a cassette is configured with at least one coupling element; at least one strand bundle can be fixed to the module, whereby said strand bundle can be split into at least two strands comprising at least one fiber optic cable; an excess length of strand can be retained by a cassette, the fiber optic cable or cables being connected to the coupling element and the cassette together with its retained strand being detachably connected to the retaining unit.

Abstract: A method of filtering optical signals (300) utilizing an optical fiber (100A-100D). The method of filtering optical signals (300) includes the steps (304) selecting an optical fiber (100A-100D) coupled to a source of optical signals, (306) disposing a core (102) in the bore (103) of the optical fiber (100A-100D) formed of a core material (105), (308) selecting a core material (105) to provide a waveguide within the optical fiber (100A-100D), (310) disposing an optical grating (114-1) in a first optical cladding layer (104) disposed about the core (102), (312) propagating an optical signal within the optical fiber (100A-100D) guided substantially within the core (102), (314) modifying a propagation path of selected wavelengths comprising said optical signal with the optical grating (114-1), and (316) determining selected wavelengths for which the propagation path is modified by selectively varying an energetic stimulus to the core (102) thereby tuning the waveguide.

Abstract: An attenuator for optical signals includes a base. A first ferrule has a first optic fiber passing through a central bore therein and attached to a first lens at an end of the first ferrule. The first ferrule is fixed in position relative to the base. A second ferrule has a second optic fiber passing through a central bore therein and attached to a second lens at an end of the second ferrule. The second lens faces the first lens. The second ferrule is fixed to the base and can be moved relative to the base by a user adjustment feature, so that the second lens may be moved relative to the first lens. The relative placement between the first and second lens controls the attenuation of the attenuator.

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: A liquid ejecting apparatus which includes a plurality of transport belts, upstream and downstream liquid ejecting units that include a plurality of liquid ejecting heads which are arranged at predetermined intervals in a direction orthogonal to the direction that the printing medium is transported through the apparatus, a maintenance unit that is provided between the transport belts, and a positioning unit that establishes the relative position between the upstream liquid ejecting unit, the upstream transport unit, the downstream liquid ejecting unit, and the downstream transport unit by moving components of the upstream liquid ejecting unit, the upstream transport unit, the downstream liquid ejecting unit, and the downstream transport unit in a direction that is orthogonal to the transport direction such that the liquid ejecting heads of the upstream and downstream liquid ejecting units face the maintenance unit during a maintenance operation.

Abstract: A variable-wedge rotating-disk attenuator for use in an ophthalmic endoilluminator is disclosed. The attenuator includes a wedge attached to an axle. The size of the wedge can be adjusted over a variable angle as measured through an arc of the wedge. The axle to which the wedge is attached rotates such that the wedge rotates around a pivot defined by the axle. The variable-wedge rotating-disk attenuator is located such that it affects the intensity of a light beam transmitted into an eye.

Abstract: A variable light controlling device comprising a substrate, an optical waveguide disposed on the substrate, a first heater and a second heater to change the optical waveguide's temperature is fabricated. And a total amount of the power supplied to the first and the second heater, or a total amount of heat emitted from both of the first and second heater, is maintained substantially constant. Then, the substrate is protected from temperature changes, thereby, stable and quick wavelength tuning operations are realized.

Abstract: A variable optical attenuator with photoelectric detector, comprising a collimator, a variable optical attenuator chip, wherein the variable optical attenuator further comprises a photoelectric detector; and the photoelectric detector receives and detects partial light from the variable optical attenuator chip. The variable optical attenuator of the invention is capable of detecting attenuation change of itself via the variable optical attenuator chip. Thus, real-time monitoring and feedback are implemented, and the attenuation performance of the variable optical attenuator is improved.

Abstract: A device for transmitting optical signals comprises two collimator units, supported to be rotatable relative to each other about a rotation axis and one derotating optical element. A first beam splitter receives input signals and splits them into at least two signals, so that they are transferred by at least two optical channels over the collimator units and the derotating optical element. After passing the second collimator unit, the signals are combined by a second beam splitter to a single signal, resulting in largely reduced variations of attenuation during rotation.

Abstract: A system is provided for characterizing optical fibers carrying signal traffic. The system includes a transmitter, a variable optical attenuator (VOA), a receiver, and a computing device. The transmitter propagates an optical test signal along a channel of a fiber pathway. The VOA adjusts the attenuation of the optical test signal from an initial, greater attenuation to a subsequent, lesser attenuation. At the same time, the computing device monitors at least one other channel of the fiber pathway and identifies effects upon the other channel(s) from the optical test signal. The computing device may communicate with the VOA and with other components of the fiber pathway to direct adjustment of the signal strength. A maximum optical test signal strength may thus be achieved that does not negatively affect signal traffic on the other channels, and the fiber pathway may subsequently be tested using the achieved maximum optical test signal strength.

Abstract: An optical device includes a housing having a front connector interface and a rear connector interface. The housing houses optics that provide an optical pathway from the front connector interface to the rear connector interface. The front connector interface is configured to be coupled with a first optical connector such that an optical signal from the first optical connector travels along the optical pathway. The rear connector interface is configured to be coupled with a second optical connector such that the second optical connector receives the optical signal from the optical pathway. The optical device includes an attenuator in the housing. The attenuator is configured to scatter the optical signal traveling along the optical pathway such that power of the optical signal is attenuated.

Abstract: A variable optical attenuator is disclosed, which attenuates a beam of light while preserving its polarization substantially independent of wavelength. The beam of light is attenuated by a filter patterned with a grating of blocking stripes with serrated edges, which partially block and partially transmit the beam of light, respectively. The serrated edges provide for low polarization dependent loss. Along a length of the filter, a mark to space ratio of blocking stripe and aperture widths increases. By a linear translation of the filter along its length attenuation can be varied to a desired value. A stepper motor with lead screw can provide a suitable linear translation to give the filter a latching property.

Abstract: The present invention provides an ultra-thin high-precision glass optic and method of manufacturing the same. The optic has an axial thickness that is less than 1,000 microns. A pattern and/or coating is disposed on a surface of the optic to provide attenuation of light in an optical system. In an embodiment, the optic is manufactured by disposing a pattern on a surface of a reticle. The pattern is covered with a first protective coating to protect the pattern. Individual optics are cut from the reticle so that each optic includes a portion of the pattern. The optic is thinned by removing material until it has an axial thickness of less than 1,000 microns. The optic is cleaned after thinning and covered with an anti-reflective coating.

Abstract: Disclosed are an optical fuse and a device for fabricating such an optical fuse. The optical fuse comprises a medium constituting a structure in which a light-emitting end of a first optical waveguide is coupled to a light-incident end of a second optical waveguide across the medium, and a light-absorbing body adapted to absorb the light. The medium is transparent to light passing through the structure, and the light-absorbing body is disposed in contact with an outer peripheral surface of the medium in such a manner as to allow a part of light emitted from the light-emitting end into the medium to reach the light-absorbing body. The optical-fuse fabricating device comprises a pair of first and second support members formed, respectively, with first and second through-holes for supporting an optical fiber, and a beam member mechanically connecting the first and second support member together.

Abstract: A method for creating an integrated linear polarizer is provided. An electro-optical component is fabricated and may include a bottom electrode, a bottom cladding layer, side cladding features, an electro-optic polymer layer, a top cladding layer, and a top electrode. After fabrication, the electro-optical component is poled to create or enhance polarization properties of the electro-optic polymer layer. The electro-optical component may be heated to at least a first threshold temperature. An electric field may then be applied to the electro-optical component. In the presence of the electric field, the electro-optical component may be cooled to at or below a second threshold temperature that is less than the first threshold temperature. Once the electro-optical component has cooled to the second threshold temperature, the electric field may be removed.

Abstract: A light applicator (27) for medical applications is proposed whose diffusor (1) comprises diffusion regions (7, 8, 9) with paraboloidal boundary surfaces (11, 12) This configuration of the diffusor (1) permits a particularly good homogenization of the distribution of light along the longitudinal axis of the diffuser (1).

Abstract: An optical receiver circuit comprising an optical converter circuit (38), comprising a photodiode and converting optical power into electrical power, a sensor circuit for deriving a control voltage VCONTR as a characteristic value of the electrical power output by the optical converter circuit (38); and an attenuator circuit (44) having a variable attenuation, the attenuation being controlled by the characteristic value of the electrical power output by the sensor circuit so as to obtain a constant output signal level of the optical receiver circuit. An output circuit is also provided and comprises a matching network (46), an amplifier stage (48) and an output transformer (50).

Abstract: A compact optical splitter module is disclosed. One type of compact optical splitter module is a planar attenuated splitter module that includes a branching waveguide network having j?1 50:50 splitters that form up to n?2j output waveguides having associated n output ports, wherein only m<n output ports are suitable for transmitting light to the at least one external output device. This provides a 1×m splitter module wherein each output port has the attenuation of a 1×n splitter module, thereby obviating the need for external attenuation. Another type of compact optical splitter module is a direct-connect splitter module that eliminates the need for an optical fiber array when coupling to external optical fibers. Another type of compact optical splitter module is a microsplitter module that serves as device and module at the same time and that eliminates the differentiation between device and module. The integration of device and module also makes manufacturing the microsplitter module cost-effect.

Abstract: The present invention achieves highly reliable optical-fiber loss adjustment at low cost, with easy work. An optical fiber is inserted from an optical fiber insertion opening into a space between an internal wall and a plurality of optical-fiber support members and, due to its self-resilience, comes in contact with the support members on its outer side. Since the radius of curvature of the fiber is sufficiently small, a loss can be adjusted with the number of turns of the fiber. The support members have a cylindrical shape and therefore come in point contact with the fiber, which can prevent microbending. Moreover, the interval (angle) between adjacent ones of the support members and the radius thereof are set such that the fiber can be led into and out of an optical-fiber adjustor, with no stress imposed.

Abstract: A planar lightwave circuit type variable optical attenuator with a small polarization dependent loss is provided. By setting the waveguide birefringence (absolute value) in first and second optical coupler sections equal to or greater than 3.5×10?4, the polarization mode coupling is made equal to or less than ?25 dB, and the effect of the polarization dependence caused by the polarization mode coupling at the cross port of the first and second optical couplers is suppressed. In addition to or independently of this, the arm waveguide length can be designed to be equal to an integer multiple of the optical beat length obtained by dividing a used optical wavelength by the waveguide birefringence.

Abstract: An electro-optical module comprising flexible connection cable and aligning capabilities is disclosed. Electro-optical devices may be soldered on a transparent substrate such as glass or a substrate comprising an optical waveguide wherein electrically conductive traces are designed, forming an electro-optical module. When such electro-optical module is inserted and aligned into a printed circuit board, the external part of the substrate, comprising electrically conductive traces and pads, referred to as flex-cable, is bent down toward the mounting plane of the PCB allowing to establish electrical connections between these pads and the PCB. The substrate may be broken along a pre-formed groove, and the external part of the substrate can be removed leaving the flex-cable section in place.

Abstract: A device and method for the spectrally-designed and controlled attenuation of a light signal, including an attenuation structure which may be placed in the proximity of a waveguide's core and which comprises a base material system containing non-uniformities having optical properties that are different from those of the host. These non-uniformities may have various natures, geometrical forms and sizes and may be created, doped or otherwise introduced in the base material system to obtain externally controllable optical properties of the whole composite material providing a broadband spectral performance.