Abstract: A method of dynamically adjusting an optical module in an optical system including a plurality of transmission channels includes the following steps: measuring the quality of the optical signal at the output of the system as defined by an error function, varying an optical parameter of at least one module of the system, measuring a differential error introduced by each variation on the error function of the optical signal at the output of the system, estimating an operating point of the system corresponding to an expected reduction of the error function, and adjusting a parameter of an optical module toward the operating point of the system.

Abstract: An all-optical 3R regenerator (AO3R) and a method for using the AO3R to retime, reshape and retransmit an optical signal are described herein. The AO3R includes a polarizer that receives an input optical signal which is of unknown, potentially varying phase and outputs a stable polarized input optical signal. The AO3R also includes a first interferometer (e.g., interferometric converter module) that retimes and reshapes the polarized input optical signal and transmits the retimed and reshaped polarized input optical signal as a polarized output optical signal. The first interferometer is able to retime the polarized input optical signal with the aid of a laser and a clock recovery mechanism.

Abstract: An integrated optical device includes a substrate, at least a face of the substrate providing a first cladding layer, the first cladding layer including a mesa formation; a waveguide core formed on the first cladding layer so that the waveguide core substantially covers the mesa formation; and a second cladding layer formed over the waveguide core and the first cladding layer.

Abstract: An assembly for providing thermal compensation to a fiber optical device is described. The optical fiber device is secured in a support structure made of a material having a negative coefficient of thermal expansion. The securing means located at on end of the support structure is made of a material having a positive coefficient of thermal expansion. The securing means is also adjustable lengthwise so as to provide longitudinal adjustment to the tension on the optical fiber device. By selecting the appropriate materials and dimensions the assembly can exactly compensate for the thermal dependency of the optical device with an overall length much smaller than assemblies based on materials with dissimilar positive CTEs.

Abstract: In an arrayed waveguide grating (AWG) comprising fist and second slab waveguides and an array of waveguides optically coupled therebetween, the angle of the array waveguides at the slab waveguides is chirped according to the following equation: &thgr;i=ArcSine (i.&Dgr;&thgr;), where i=−(N−1)/2, −(N−1)/2+1, . . . , +(N−1)/2 where i is the array waveguide number, N is the number of array waveguides, and &Dgr;&thgr; is a constant. The chirping removes third-order aberration (COMA) which would otherwise cause asymmetry in the AWG output channel signals, especially where the AWG has a flattened passband.

Abstract: An optical waveguide (1) with a multi-layer core (6) comprises a substrate (2), a composite core waveguide (7) formed on the substrate (2) and at least one upper cladding layer (8) embedding said core waveguide (7). The core waveguide (7) is characterized by a composite core layer (6) comprising a first core layer (4) with a consolidation temperature T1C formed on the substrate (2) and at least one other core layer (5) formed on the first core layer (4), wherein the softening temperature T2S of at is least one of said at least one other core layers (5) is equal to or less than the consolidation temperature T1C of at least one underlying core layer (4, 5).

Abstract: An all-optical 3R regenerator (AO3R) and a method for using the AO3R to retime, reshape and retransmit an optical signal are described herein. The AO3R includes a polarizer that receives an input optical signal which is of unknown, potentially varying phase and outputs a stable polarized input optical signal. The AO3R also includes a first interferometer (e.g., interferometric converter module) that retimes and reshapes the polarized input optical signal and transmits the retimed and reshaped polarized input optical signal as a polarized output optical signal. The first interferometer is able to retime the polarized input optical signal with the aid of a laser and a clock recovery mechanism.

Abstract: A hybrid optical component is described incorporating a planar lightguide circuit (PLC) chip 2 having at least two waveguides provided thereon which are separated by a trench, and a MEMS chip 3 attached to the PLC chip and incorporating a MEMS element displaceable relative to the trench so as to control the passage of an optical signal between the two waveguides. A cap 4 is sealingly engaged with the PLC chip 2 to form a housing therewith which houses said MEMS chip 3 hermetically therein. The component may act as a variable optical attenuator (VOA) device in which a MEMS shutter attenuates an optical signal passing between two waveguides, or may be an optical switch in which a MEMS mirror is used to switch an optical signal from a first waveguide between at least two other waveguides which intersect with the first waveguide at the trench.

Abstract: A method of dynamically adjusting at least one optical module in an optical system including a plurality of transmission channels includes the following steps:

Abstract: In an optical module comprising an arrayed waveguide grating multiplexer-demultiplexer component having at least one inlet waveguide and at least one outlet waveguide, the module is integrated and comprises at least one inlet optical fiber and at least one outlet optical fiber, said inlet waveguide presenting an optical coupling interface with the inlet optical fiber and said outlet waveguide presenting an optical coupling interface with the outlet optical fiber, and a thin film filter is inserted directly at the optical coupling interface between the inlet and/or outlet waveguide(s) of the multiplexer-demultiplexer component and the inlet/outlet optical fiber(s) of the module.

Abstract: A semiconductor optical component is disclosed which comprises a current injection region and at least one electrically isolated region referred to as a first plateau, each region containing a contact layer of an alloy based on gallium arsenide, GaAs, deposited on a semiconductor material upper confinement layer. The component further comprises in the first plateau a dielectric material isolation layer on top of the contact layer. An attachment layer is disposed between the contact layer and the isolation layer to increase the adhesion of the isolation layer to the contact layer. A method of fabricating the above kind of component is also disclosed.

Abstract: A phasar (arrayed waveguide grating) including a segmented waveguide disposed between the phasar and one of the single-mode waveguides on either the input or output side of the phasar. The segmented waveguide is optimized to produce a flattened passband of the phasar, thereby minimizing variations in the phasar spectral response. The optimization may be performed by an evolutionary algorithm which generates random variations into the design population and selects the better members in a multi-generational selection process. The flattened passband phasar is particularly useful in a wavelength-division multiplexing (WDM) fiber communications network.

Abstract: Arrayed Waveguide Grating with Reduced Crosstalk An Arrayed Waveguide Grating (AWG) having reduced adjacent crosstalk is described. Interspersed ones (21) of the output waveguides of the AWG are of different widths to the remaining output waveguides (23), along corresponding portions of their lengths, preferably in at least an initial portion of the fan-out region. Passband unifonmity is maintained by making all the output waveguides substantially of the same width at the output slab coupler. In the illustrative embodiment, alternate ones of the plurality of output waveguides are tapered to a narrower width (W2) between first and second portions (22,24) thereof and the remaining ones of the output waveguides are of a substantially uniform width (W1) between corresponding first and second portions thereof.

Abstract: An optical waveguide feedthrough comprising

Abstract: The invention is related to an optical device comprising, in an housing (1) with a defined gas atmosphere:

Abstract: The invention concerns a semiconductor optical amplifier. The optical guide structure of this amplifier comprises a rectangular cross-section active stripe (12). Its material is homogeneous and it is subjected to a tensile strain sufficient to render the amplifier insensitive to the polarisation of the light to be amplified.The invention finds an application in optical telecommunications.

Abstract: In order to facilitate resuming molecular beam epitaxy after etching a substrate or an epitaxial layer, the etching method is implemented in an ultra-high vacuum, and it consists in producing at least two simultaneous chemical beams converging towards the substrate or the layer, the beams being formed of substances, each of which is capable of reacting with elements of different types in the substrate or the layer so as to form volatile compounds. Application in particular to manufacturing photonic and optoelectronic components.

Abstract: The demultiplexer has two couplers connected together by a grating of waveguides that are all of different lengths. To make a grating component of low order and that occupies little space, each waveguide has three adjacent segments having radii of curvature that are respectively positive, negative, and positive. The demultiplexer is particularly applicable to duplex optical communications.

Abstract: A Bragg grating is produced in a semiconductor component by wet etching through a resin mask developed after holographic exposure. This causes the regions of the grating at the boundary of other parts of the component to be etched more deeply. To compensate this, the method includes further irradiation through a second mask disposed at a distance from the part of the resin mask that defines the location of the grating. Applications include opto-electronic components.

Abstract: Prior to using etching to form a plateau that is to constitute a laser ridge and that is to be provided with a cover constituting a top electrode, the surface of the cover is initially protected with a dielectric mask and the flanks of the cover are then protected with a dielectric coating. The dielectric coating is initially deposited uniformly over the surface and the flanks. It is then etched by directional means so that it remains on the flanks only. The invention is particularly applicable to making an optical amplifier.