Other

France Telecom

Alcatel

L'etat Francais, Represente Par Le Ministre Des Ptt, Centre National

Photline Technologies

Etat Francais Represente Par Le Ministre Delegue Aux Postes Et

France Telecom-establissement Autonome De Droit Public (centre National D'e

Alain Carenco

Louis Menigaux

Joseph Zyss

Henri Porte

Jérôme Hauden

Pascal Mollier

Elchuri K Rao

Andre Scavennec

Pierre Sansonetti

Julienne Liang

Luc Riviere

Anatole Lupu

Sylvie Fouchet

Anatolic Lupu

Regine Levenson

Herve Baratte

Anatolie Lupu

Dominique Lesterlin

An electric-optic modulator includes a block of crystal having electro-optic properties, the block extending lengthways along a long axis and having a light guide which extends between a light guide input and a light guide output. An electric modulation signal acts on an interaction zone of the block via coplanar electrodes together with the light guide via a dielectric layer. The electrodes are disposed on a main long face of the block and the interaction zone is elongated more or less along the long axis. The light to be modulated arrives through an input optical fiber which is connected to the light guide at the light guide input on a first face of the block. The modulated light leaves the modulator through an output optical fiber connected to the light guide output on a second face of the block. The first face and the second face are one single face (D) which is parallel to the long axis.

Electro-optic modulator, the production method therefor and the block for implementing same

A device is presented that is adapted to have an optical wave travel through it and to filter that wave in terms of wavelength, in which an optical parameter of the device varies along the path of the wave in such a manner that the device has a series of sections each constituted by a pair of two successive segments, one in which the values of the optical parameter are less than an average value and the other in which the values of the optical parameter are greater than the average value. The device has at least one zone of more than two sections. The two sections have lengths alternately less than and greater than an average length of the sections in that zone.

Grating-type optical filter with apodised spectral response

The invention relates to an optical multiplexer/demultiplexer able to combine and/or separate at least two optical signals amongst n propagating at different wavelengths, characterised in that it comprises at least one central waveguide ( ) and two lateral waveguides ( ), each lateral waveguide ( and ) constituting with the central guide ( ) a pair of waveguides, each pair being disposed so as to allow a bidirectional evanescent coupling of an associated wavelength between the guides in each pair ( ) and ( ), the coupling being selective with respect to wavelength and assisted by at least one etched grating (&Lgr;), the said waveguides ( ) being designed so that the multiplexer/demultiplexer has a functioning independent of the state of polarisation of the signals. The present invention applies to optical filters and/or direct-access networks for a bidirectional communication in the 1.3&plusmn;&mgr;m window simultaneously with a video distribution at 1.5 &mgr;m.

Optical multiplexer/demultiplexer with three waveguides

The invention relates to an optical multiplexer/demultiplexer able to combine and/or separate at least two optical signals amongst n propagating at different wavelengths, characterised in that it comprises at least one central waveguide ( ) and two lateral waveguides ( ), each lateral waveguide ( and ) constituting with the central guide ( ) a pair of waveguides, each pair being disposed so as to allow a bidirectional evanescent coupling of an associated wavelength between the guides in each pair ( ) and ( ), the coupling being selective with respect to wavelength and assisted by at least one etched grating (&Lgr;), the said waveguides ( ) being designed so that the multiplexer/demultiplexer has a functioning independent of the state of polarisation of the signals. The present invention applies to optical filters and/or direct-access networks for a bidirectional communication in the 1.3 &plusmn; &mgr;m window simultaneously with a video distribution at 1.5 &mgr;m.

The invention relates to a process for producing a structure with integrated optical waveguide and mirror, comprising the stages consisting in:

Process for forming a structure with integrated optical waveguide and

In a method of manufacturing a planar optical waveguide based entirely on polymer materials an active polymer is deposited onto a semiconductor substrate between two layers of buffer polymers chosen so that the difference in refractive index on each side of the active polymer is between 0.005 and 0.5 and preferably between 0.01 and 0.4.

Method for manufacturing strip optical waveguides

Method for making an integrated guide/detector structure made of a semiconductive material. This method consists of epitaxially growing on a semiconductor (2, 1) a lower confinement semiconductive film (4), a semiconductive guide film (6) and an upper semiconductive confinement film (8) with the same type of conductivity, the guide film being inserted between the confinement films having a prohibited band of energy smaller than that of the confinement films, of etching the upper film so as to form a guide strip with one extremity defining a first step (12) ending by a lateral broadening (28a) inside a plane parallel to the epitaxial films, of etching the released guide film so as to form a second step (16) adjacent to the first step, of epitaxially growing a semiconductive detector film (18) with this type of conductivity whose prohibited band of energy is smaller than that of the confinement films and the guide film, of eliminating that portion of the detective film covering the guide strip, and of forming the detector in the detecting film opposite the steps so as to embody a butt coupling between the guide film and the detector.

Method for making an integrated light guide detector structure made of a

Process for locally increasing the refractive indexes of an electrooptical material usable in guided optics and material obtained by this process. The process according to the invention consists of carrying out an implantation of ions (6) of sulphur or a metallic dopant able to take the place of a cation of the crystal lattice of the ferroelectric material (2), followed by annealing at between 300.degree. and 600.degree. C. in order to rearrange the crystal lattice disturbed during implantation and for activating the implanted ions. Ion implantation is carried out in an inclined direction (60) with respect to the normal to the surface of the monocrystalline material (2). For a LiNbO.sub.3 monocrystal, use is made of Ti ions as the dopant. This process makes it possible to produce a guide layer (4) having ordinary and extraordinary refractive indices above those of the pure monocrystal.

Process for locally increasing the refractive indexes of an

This invention relates to an increase in the low longitudinal resonance frequencies of microwave transmission lines known as symmetrical lines, comprising two coplanar and parallel narrow conductive strips. According to the invention, the line further comprises a longitudinal and wide planar conductive strip which is parallel to one of the narrow strips at a sufficient distance not to substantially disturb the characteristic impedance of the initial symmetrical line and which is connected to the narrow strip by small planar end conductors thereby forming a longitudinal flat cavity. The cavity offers a first resonance frequency much greater than those of the initial symmetrical line and consequently affords a higher useful frequency bank of signals to be transmitted. The end conductors allow the line to be connected to coaxial connectors. In other embodiments, the cavity is divided into several resonant sub-cavities in order to raise the pass-band.

Microwave transmission line of the symmetrical type and with two

Process for the production of a monolithic integrated optical device

The electrode structure comprises in each section three parallel microbands of identical width, the first and second microband covering first and second optical guides respectively and being separated by a width giving to the propagating line which they form a characteristic impedance equal to the required adaptation impedance; the third microband is far enough away from the second band for the contribution of the former to such characteristic impedance to be negligible. The covering of the first and second optical guides by the first and second microbands alternates from one section to the next section and the passage from a first section to a second section is obtained by a transition zone comprising inclined microbands.

Electro-optical directional coupler with three electrodes and

A method for balancing an integrated optical device having at least two similar arms each constituted by a light guide consists in depositing a thin metal film on at least one of the two guides, in measuring the unbalance between the light intensities transmitted by the two arms and then in adjusting the dimensions of the thin metal film in order to cancel the unbalance.

Growing community of inventors

Bourg-la-Reine, France

Alain Carenco