Pirelli & C. S. P. A.

Corning Incorporated

Avanex Corporation

Corning O.t.i. Spa

Corning Oil Spa

Google Inc.

Maurizio Tormen

Marco Romagnoli

Camilla Bonati

Matteo Cherchi

Giacomo Antonio Rossi

Giacomo Gorni

Guido Oliveti

Michele Belmonte

Elisabetta F Rondinella

A device for crossing optical beams. At least a first input optical waveguide is directed along a first axis, a second optical waveguide is directed along a second axis inclined with respect to the first axis, and a photonic crystal having a regular periodicity in an optical crossing region at the intersection of said first and second axis has, opposite the first and second input waveguides, a first and a second output waveguide to provide for exit beams.

Device for crossing optical beams, in particular in an integrated optical circuit

A method for guiding electromagnetic radiation by providing a photonic crystal made of a bulk material with a predetermined refractive index and having a periodic array of holes with predetermined radius, and feeding to that region an electromagnetic radiation having a wavelength in the fundamental photonic band and so related to the refractive index of the bulk material, to the radius of the holes and to the period of the array that, starting from an isotropic distribution of the wave vectors within a first angular range that is twice the angular extension of the first irreducible Brillouin zone of the photonic crystal, the corresponding group velocity vectors are rearranged as concerns direction and module so that at least 50% of them become directed within a second angular range that is about one-third of the first angular range and the width at half-maximum of the distribution of the modules of the vectors is lower than about two-thirds of the second angular range.

Method for guiding an electromagnetic radiation, in particular in an integrated optical device

A device for varying the direction of an optical beam. A first waveguide is directed along a first direction, a second waveguide is directed along a second direction different from the first direction, and a bending region is interposed between the first and the second waveguide. The bending region has a photonic crystal having a regular periodicity and at least a first and a second crystal axes substantially aligned with the first and second directions, and a reflecting surface delimiting the photonic crystal and so positioned and oriented as to reflect an optical beam coming from the first waveguide toward the second waveguide.

Device for bending an optical beam, in particular in an optical integrated circuit

An optical wavelenth selective filter on an optical waveguide and a method of making the same is provided. The filter is able to transmit a first predetermined band of wavelengths and to reflect a second predetermined band. The filter further includes a plurality of transmissive couples and reflective couples in series, with each of the couples including a first zone of high refractive index and a second zone of low refractive index adjacent to each other so as to form a structure with a high gap modulated refractive index.

Optical multi/demultiplexer device, optical wavelength selective filter and method of making filter

An optical signal amplification device ( ) comprises an optical amplifier ( ) having a wavelength-dependent gain and an equalization device ( ) optically coupled in series to the optical amplifier and having a wavelength-dependent transmission function that substantially equalize the gain of the optical amplifier, the equalization device comprising a waveguide Bragg grating having a substantially constant refractive index envelope and a chirp rate that varies in such a way as to obtain the wavelength-dependent transmission function.

Gain flattening optical filter, optical amplifier comprising such an optical filter and method for manufacturing such an optical filter

To produce a fiber laser ( ) a double-cladding active fiber ( ) doped with Yb is predisposed to receive, near a first end ( ), a UV radiation suitable to write a first Bragg grating; during the writing process, a scanned pumping radiation is fed to the first end of the active fiber in order to excite an amplified stimulated emission between the first grating and the reflecting surface of a second end ( ) of the active fiber, previously cut and cleaned, and to consequently induce a laser emission from the active fiber; the optical power of the laser emission is measured and processed to obtain the laser efficiency; when a maximum value of the efficiency is reached, the writing process is stopped; similar steps are used to write a second grating near the second end ( ) of the active fiber.

Method for producing a fiber laser

A method for writing a Bragg grating in a waveguide comprises the steps of placing the waveguide in a writing position in which the waveguide extends essentially along one axis; generating a beam of ultraviolet radiation; executing a first and a second scan with the said beam along the waveguide through a phase mask, in such a way as to generate interference fringes capable of modifying the refractive index along the said waveguide in a predetermined way; moving the phase mask, during the first or the second scan, with an oscillatory motion about one of its equilibrium positions and along a direction lying at an angle of less than 90&deg; to the axis of the said waveguide, in such a way as to produce, in this scan, an essentially zero envelope of the refractive index; and varying the intensity of the energy of the ultraviolet radiation in a controlled way along the waveguide during the first and the second scan, for example by controlling the scanning velocity.

Method and equipment for writing a Bragg grating in a waveguide

In order to create a diffraction grating in an optical fiber with a predetermined pattern of the refractive index, an ultraviolet radiation beam ( ) is scanned ( ) along a phosensitive portion (F&prime;) of the fiber through a phase mask ( ) and, during the scan, the beam intensity ( ) and the mask-fiber distance ( ) are controlled moment by moment in such a way as to obtain the desired patterns of the mean value and of the envelope of the refractive index, respectively.

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Belluno, Italy

Maurizio Tormen