Abstract: An interferometer includes: a first glass plate optically coupled to a second glass plate, forming an optical interferometric cavity therebetween; a first reflective coating coupled to the first glass plate within the optical interferometric cavity, where the first reflective coating is partially reflective; a second reflective coating coupled to the second glass plate within the optical interferometric cavity, where the second reflective coating is at least partially reflective; and a tuning plate residing within the interferometric cavity and optically coupled to the first and second reflective coatings, where the tuning plate comprises a photosensitive material, where a refractive index of the photosensitive material may be modified by exposure to light.

Abstract: An optical modulator comprises a Z-cut lithium niobate substrate (21) on which is formed a Mach-Zehnder interferometer having two generally parallel waveguides (23, 25) lying beneath a buffer layer of dielectric material (27). First and second ground electrodes (29, 33) and a hot electrode (31) are disposed on the buffer layer (27), the first and second ground electrodes (29, 33) being spaced either side of the hot electrode (31), the hot electrode (31) and the first ground electrode (29) being proximate to at least apart of the respective waveguides (25, 23). The electrode structure is unsymmetrical in that (a) the hot electrode and the first ground electrode each have a width substantially less than that of the second ground electrode and or (b) the spacing between the first ground and hot electrodes is different from the spacing between the second ground and hot electrodes. whereby a range of chirp values can be obtained.

Abstract: The present invention propose to use an optical multiplexer associated with an optical clock as a wavelength converter. Each RZ coded tributary will be carried by a single wavelength (channel) passively interleaved with the others without interferometric interaction hence achieving a not necessarily perfect OTDM. This input data stream as optical data signal composed of different wavelengths is then launched on at least one data access of said optical multiplexer used as a wavelength converter. An optical clock at the desired bit-rate is launched on the probe access of said optical multiplexer synchronously to the multi-wavelength data stream. At the output, the initial clock wavelength is converted on data signal using the gain conversion property of the optical multiplexer. In such a way, a data stream of substantially higher bit-rate is obtained while due to a very precise synchronization a lost of data is minimized.

Abstract: An optical module comprises a support (T) on which an optical fibre (F) is mounted. Introduced on the support (T) is a V-groove (VG) that serves only to fix the fibre (F). Applied perpendicularly to the groove (VG) is a strip-shaped contact layer (CL). The fibre (F) is pressed into the groove (VG). When the fibre (F) is pressed into the groove (VG), the contact layer (CL) forms a mechanical joint with the fibre (F) in the form of a cold weld. This functions particularly well in the case of glass fibres having a contact layer of aluminium (Al). The contact layer (CL) is preferably composed of a plurality of narrow strips extending perpendicularly to the groove (VG).

Abstract: An amplifier including a first input for a first at least two input signals having mutually distinct wavelengths, a first output for a first at least two output signals, the first at least two output signals having said mutually distinct wavelengths, a first circulator including an input port coupled to the first input, an output port coupled to the first output, and an intermediate port coupled to a first end of a selective reflection circuit, and, a second circulator including an intermediate port coupled to a second end of the selective reflection circuit, an output port coupled to a first selective splitter, and an input port coupled to a second selective splitter, wherein the first selective splitter and the second selective splitter are centered about a first selected wavelength amongst the mutually distinct wavelengths.

Abstract: The invention relates to an optical fiber presenting a core, cladding, and a grating written by irradiation and coupling at least one light mode into the cladding so that it is dissipated therein. The invention proposes causing the mean index to vary progressively along the grating, at least at the ends of the grating. The progressive variation in mean index or in the amplitude of index modulation for writing the grating serves to limit insertion losses to the filter formed by the grating. Analogously, in a written-in grating, the invention provides the equivalent of progressively varying the core size of the fiber for interconnecting two optical fibers presenting different core diameters. The invention is applicable in particular to gain-equalizing filters in WDM transmission systems.

Abstract: A self-adjusting optical add-drop multiplexer monitors the power in a drop signal and attenuates the power in an add signal to match the power in express WDM channels (signals). When used in a fiber network, and more particularly, in a metro network, the deleterious effects of optical amplification are reduced. Power attenuation is also used in an optical switching assembly particularly useful in two-fiber ring network. The optical switching assembly monitors drop channels from the two rings of the network and attenuates the add channel(s) accordingly. An optical switch operates to direct the drop signal from one of the two rings to a receiver in accordance with a control signal based on the monitored drop channels. The self-adjusting optical add-drop multiplexer also monitors the power in the drop signals and issues an alarm if the drop signal is of a power level above or below predetermined levels.

Abstract: The present invention provides a multi-functional separator which may be used as a demultiplexer or as a multiplexer in wavelength division multiplexed optical communication systems. The preferred embodiment of the multi-functional separator includes a first polarization beam splitter, a non-reciprocal rotator; a reciprocal rotator, a second polarization beam splitter, and a non-linear interferometer. Each of the polarizing input and polarizing output ports includes an optical fiber, a collimator, a birefringent walk-off plate and a non-reciprocal optical rotator. The multi-functional separator is easily aligned by adjusting the positions of each of the polarizing input and output port. Further embodiments of the present invention provide additional optical isolation, optical circulation, optical comb filtering and/or two-stage channel separation capabilities.

Abstract: The present invention relates to a method for trimming birefringence of an integrated optical device with at least one waveguide having a birefringence characteristic, comprising the steps of providing at least one electrode on top of the waveguide, and applying power equal to or above a predetermined power level to said at least one electrode for causing a change of the refractive indices of the waveguide.

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: An optical module box made of aluminum that has a reworkable glass-sealed fiber feedthru is disclosed. A fiber is inserted through a glass seal and a C-seal for hermetically sealing an opening in the optical module box. In a first embodiment, a module box employing a single-fiber fiber feedthru is described. In a second embodiment, a module box employing a 2-fiber feedthru is described. In a third embodiment, a module box employing a ribbon fiber feedthru is described. A module box having an opening with a single-fiber feedthru, comprising a C-seal; a glass sealed feedthru having a front tube and a back tube, the back tube of the glass sealed feedthru extending through the C-seal; and a fiber passing through the glass sealed feedthru and the C-seal, thereby hermetically sealed into the opening of the module box.

Abstract: A method of improving performance of an optical amplifier and an optical fiber amplifier including an optical fiber having a zero-dispersion wavelength, and at least one Raman pump that provides pump power to the optical fiber at a predetermined wavelength to allow transfer of at least a portion of the pump power to a first adjacent wavelength that is less than the zero-dispersion wavelength, and to a second adjacent wavelength that is greater than the zero-dispersion wavelength.

Abstract: An optical component comprising an optical waveguide and adjacent to it at least one grating array adapted to reflect stray light away from said optical waveguide. The use of a grating array with a plurality of structures like polygons or stripes gives the possibility to define a multiple of reflection directions. This is obtained by using polygons layed out in different orientations up to a random one or a Bragg grating preferably defined with a non-uniform period (chirped). Such grating arrays are usually structured within the same layer as the optical waveguide core layer.

Abstract: A method and structure are disclosed with a simplified approach for fabricating a LiNbO3 wafer with Ti indiffusion wafeguide on the surface that is domain inverted. The method involves indiffusing Ti into LiNbO3 with a predefined temperature and time indiffusion range, a Li enriched and dry oxygen atmosphere, which allows making optical waveguides on the z? crystal face without any significant domain inversion occurring on the z+ face of the crystal. This allows for subsequent poling without the need of any additional removal of the thin domain inverted layer which would otherwise appear on the z+ face. Even in instance where a thin domain inversion layer is formed, it is insufficient thick to prevent poling, eliminating the need for the grinding process.

Abstract: Small form factor package structures are disclosed for LiNbO3 optical modulator by reducing the package dimension for minimize the unused free space inside a modulator package. If a first aspect of the invention, the structure of the small form factor package for LiNbO3 optical modulator employs a metal round block having an inner part that is made of zirconia or glass like borosilicate BK7 or Pyrex and the outer part that is made with stainless steel or kovar. The inner and outer parts represent a two-pieces optical fiber assembly that are held together by a resin. In a second aspect of the invention, a surface of the lithium niobate chip is attached to a surface of the metal round block (or a glass block) that results in an angular positioning of the lithium niobate chip inside the optical package, which significantly reduces the mechanical stress induced by different polishing angle of the metal round block as well as the polishing angle of the lithium niobate chip.

Abstract: The invention relates to an optical module and to method for manufacturing an optical module comprising the steps of: providing a groove in a substrate for positioning an optical component, providing the optical component, bonding the optical component to the groove by means of an aluminium-oxide bonding process, whereby an aluminium layer is formed on a lower portion of the optical component.

Abstract: An optical package comprises an optical element (e.g., a filter), a reflective surface, an input optical fiber and an output optical fiber. A light signal travels through the input fiber and through the element where it is shaped or modified a first time. The shaped light signal is reflected by the reflective surface and is again transmitted through the element where it is shaped or modified a second time. The twice-shaped light signal then travels out through the output fiber. The package thereby utilizes the element two times. The package is useful in wavelength division multiplex (WDM) telecommunication systems and other light processing systems.

Abstract: The choice for the optical coupling device of a holder that has only one support makes it possible to keep this optical component compact. This is advantageously achieved in that according to the invention the support surrounds the extensible element. The carrier of the optical waveguide thus remains in the immediate environment of the support and the point at which the optical coupling device is to be attached to the optical component. The alignment of the end of the optical waveguide is thus not impaired by unavoidable curvatures of the optical component. The configuration according to the invention of the support of an alternative optical coupling device with a movable arm as an additional connection to the hinge-like web at one end of the carrier of the optical waveguide makes it possible to achieve even more precise alignment of the end of the optical waveguide.

Abstract: A multiple-port optical device uses improved fiber ferrules comprising various capillary designs and shapes to precisely position optical fibers and, in particular, the optical fiber cores. The fibers are screened for geometric characteristics which further aide in precisely positioning the fiber cores. The ferrules, capillaries, fibers, and adhesives are combined to reduce adverse thermal effects and maintain the position of the fibers over a broad range of environmental conditions in which DWDM packages and modules are required to operate.

Abstract: In accordance with an exemplary embodiment of the present invention, an optical device includes a first element which decomposes said optical signal into a first beam and a second beam with the first beam being in a first polarization state and the second beam being in a second polarization state. The first and second polarization states being orthogonal to one another and including each of said multiple channels. The optical device further includes a second element which transforms the first beam into a first elliptically polarized state having odd channels in a third polarization state and even channels in a fourth polarization state having even channels in the third polarization state and odd channels in the fourth polarization state; and a third element which combines the odd channels into a first output port and the even channels into a second output port.