France Telecom

French State Represented by the Minister of Post, Telecommunications and

French State, Represented by the Minister of Post, Telecommunications

Jean-Pierre Goedgebuer

Henri Porte

Jean-Marc Merolla

Laurent Larger

Andre Hamel

Yvon Sorel

Jean-Claude Simon

Jean-Francois Kerdiles

Laurent Duraffourg

Vladimir Oudaltsov

Pierre-Luc Francois

Laurent Langer

Youri Mazourenko

An optical binary code transmission system comprising a sender comprising: means for generating a light beam; phase-shifter means; attenuator means whereby the intensity of the lateral modes is sufficiently low for there to exist at the most only one photon in the lateral modes. The phase-shifter means of the sender impose a phase-shift that is chosen randomly to be equal either to 0 or to &#x3c0;/2 for a first bit value or either to &#x3c0; or to 3&#x3c0;/2 for a second bit value, and the receiver comprising means for detecting the presence of a photon in the first lateral mode and means for detecting the presence of a photon in the second lateral mode, a first bit value being detected if the presence of a photon is detected in the first lateral mode and a second bit value being detected if the presence of a photon is detected in the second lateral mode.

System for secure optical transmission of binary code

A sender device for sending an encrypted signal, the device comprising a chaos generator producing an encrypted electrical signal and a feedback loop comprising delayline-forming means, non-linear means, and mixer means which receive the loop signal on one input and the signal to be encrypted on another input, wherein the feedback loop includes filter-forming means which limit the spectrum of the encrypted signals to one or more spectrum bands.

Devices for emitting or receiving signals encrypted by deterministic chaos, and a transmission system, in particular a radio transmission system, including such devices

Device for sending or receiving a signal encrypted using deterministic chaos

Method and apparatus for quantum distribution of an encryption key

The invention relates to an optical transmission system that implements encrypting of an information carrying signal by deterministic chaos. The system includes a transmitter (1), a receiver (4), and one transmission channel coupled between the transmitter (1) and the receiver (4). The transmitter (1) includes a deterministic chaos generator (3) coupled to an encoding system (2). The deterministic chaos generator (3) includes a wavelength tunable laser-emitting diode (33) and a feedback loop (34). The active layer of laser diode (33) is offset controlled by a laser signal passed through a non-linear optical element (32) and a delay line (31). The receiver (4) has a deterministic chaos generator (7) coupled to a synchronizer (6) and a decoder coupled to the synchronizer (6). Preferably, chaos generator (3) is the same as chaos generator (7). Other features are disclosed.

Optical transmission system implementing encrypting by deterministic

A multi-purpose component with integrated optics includes an optical light guide (12) formed on one face of a substrate (10) made of a double refracting material having neutral axes orientated so that one electromagnetic wave extending into the guide (12) is split up into two waves having polarizations perpendicular to each other and along the neutral axes. A power source (18) applies an electric filed perpendicular to the optical light guide (12) and uniformly along the guide (12). Two rectilinear polarizers (20, 22) with polarization directions (d1, d2) parallel to each other are each disposed at one extremity of the guide (12). The component also includes focussing means (24, 26, 28, 30). The component has particular utility for tuneable optical filtering and optical telecommunications.

Multipurpose component with integrated optics and distribution network

Device able to continuously tune a coherent and rectilinearly polarized light source. It includes an electro-optical device (5) forming a spectral filter with an electrically modulable transfer function, this electro-optical device being provided so as to select a particular longitudinal mode from all the longitudinal modes able to oscillate inside the external cavity for which the source (1) is provided and which is ended by a reflecting device (3) towards the source of the light emitted by this source, and an electro-optical device (4) for varying the optical length of the cavity, this variation device being placed in the cavity and provided so as to continuously move the position of the selected longitudinal mode, each electro-optical device including a compact electro-optical crystal.

Device for continuously tuning a coherent and rectilinearly polarized

Growing community of inventors

Pouilley les Vignes, France

Jean-Pierre Goedgebuer