PGT PHOTONICS S.P.A. Patent applications |
Patent application number | Title | Published |
20120057881 | DISPERSION TOLERANT OPTICAL SYSTEM AND METHOD - An optical communication system and method of use are described. The system comprisesan optical source adapted to receive a digitally encoded data signal comprising sequences of data at a data rate (B) and comprising two signal levels representing a first state and a second state of the data signal, the optical source being adapted to produce an optical signal substantially frequency modulated with frequency excursion Δν comprising a first instantaneous frequency (ν | 03-08-2012 |
20100232802 | OPTICAL TRANSMISSION SYSTEM WITH OPTICAL CHROMATIC DISPERSION COMPENSATOR - Optical transmission system ( | 09-16-2010 |
20100196014 | METHOD AND DEVICE FOR HITLESS TUNABLE OPTICAL FILTERING - The method for filtering an optical signal comprising a plurality of channels lying on a grid of optical frequencies equally spaced by a frequency spacing and occupying an optical bandwidth, comprises: a) operating an optical filter comprising a plurality of resonators, wherein a first resonator of the plurality is optically coupled to the optical signal and the remaining resonators are optically coupled in series to the first resonator, so that a respective resonance of each one of the plurality of resonators falls within a first frequency band having bandwidth less than or equal to 15 GHz; b) operating the optical filter so as to obtain a separation between said respective resonance of at least one resonator with respect to said respective resonance of at least another different resonator, the separation being greater than or equal to 25 GHz; c) operating the optical filter so that said respective resonance of each one of the plurality of resonators falls within a second frequency band, different from the first frequency band, having bandwidth less than or equal to 15 GHz, wherein during the procedure from step a) to step c), at least one among said respective resonance of the at least one resonator and said respective resonance of the at least another different resonator is moved also outside a frequency region spanning between, and including, the first and the second frequency band. A corresponding device for filtering an optical signal is disclosed. | 08-05-2010 |
20100189441 | METHOD AND DEVICE FOR HITLESS TUNABLE OPTICAL FILTERING - The method for filtering an optical signal comprising a plurality of channels lying on a grid of optical frequencies equally spaced by a given frequency spacing and occupying an optical bandwidth, comprises: a) splitting the optical signal into a first and a second portion spatially separated, wherein the first portion comprises the channels which lie on a first sub-grid comprising a first set of the optical frequencies equally spaced by the double of the frequency spacing and the second portion substantially comprises the remaining channels; b) operating a first optical filter comprising a plurality of resonators, wherein a first resonator of the plurality is optically coupled to the first portion and the remaining resonators are optically coupled in series to the first resonator, so that a respective resonance of each one of the plurality of resonators falls within a first frequency band having bandwidth less than or equal to 15 GHz and comprising a first channel belonging to the first portion; c) operating a second optical filter comprising a plurality of respective resonators, wherein a respective first resonator of the plurality is optically coupled to the second portion and the remaining resonators are coupled in series to the first resonator, so as to obtain a first separation between each resonance of at least one resonator of the second optical filter falling within the optical bandwidth and a respective resonance of at least another different resonator of the second optical filter nearest to said each resonance, the first separation being greater than or equal to 25 GHz; and d) recombining the first and second filtered portions. A corresponding optical device for filtering an optical signal is disclosed. | 07-29-2010 |
20100183312 | METHOD AND DEVICE FOR HITLESS TUNABLE OPTICAL FILTERING - The method for filtering an optical signal comprising a plurality of channels lying on a grid of optical frequencies equally spaced by a frequency spacing and occupying an optical bandwidth, comprises: a) operating an optical filter comprising a plurality of resonators each having a respective free spectral range, wherein a first resonator of the plurality is optically coupled to the optical signal and the remaining resonators are optically coupled in series to the first resonator, so that a respective resonance of each one of the plurality of resonators falls within a first frequency band having bandwidth less than or equal to 15 GHz; b) operating the optical filter so as to obtain a separation between any resonance of at least one resonator falling within the optical bandwidth with respect to a resonance of at least another different resonator nearest to the any resonance, the separation being greater than or equal to 150 GHz and no more than 1 THz; c) tuning all the resonators of the optical filter so as to move all respective resonances of the resonators by a respective frequency interval greater than the frequency spacing while maintaining a distance between the any resonance of the at least one resonator with respect to the nearest resonance of the at least another different resonator not less than 150 GHz and no more than 1 THz; and d) operating the optical filter so that a further respective resonance of each one of the plurality of resonators falls within a second frequency band, different from the first frequency band, having bandwidth less than or equal to 15 GHz. A corresponding device for filtering an optical signal is disclosed. | 07-22-2010 |
20100091804 | PHASE CONTROL BY ACTIVE THERMAL ADJUSTMENTS IN AN EXTERNAL CAVITY LASER - The present invention relates to a wavelength tuneable external-cavity laser module, the laser being tuneable across a predetermined wavelength range and comprising: a thermally stabilised substrate; a gain medium for emitting an optical beam passing through the external cavity along an optical axis, said gain medium being placed in thermal contact with the thermally stabilised substrate; an end mirror for receiving and reflecting the optical beam within the external cavity, and a phase element for controlling the phase of the optical beam and being positioned within the external cavity between the gain medium and the end mirror, wherein said phase element comprises a material having a refractive index that varies in response to changes in temperature and has a transmissivity substantially independent of wavelength across said predetermined wavelength range. The thermally-controllable phase element in the laser external cavity is configured so as to induce a phase variation that compensates the drop in the output power due to ageing or to external temperature variation. According to a preferred embodiment, a heating element is placed in thermal contact to the phase element. The temperature of the phase element can be increased to “bring back” the output power to a value very close to the initial value. Preferably, the phase element is a silicon plate. By thermally controlling an intra-cavity phase element it is possible to vary continuously the output power as a function of the injection current. Therefore, the solution has the advantage that it is possible to configure the ECL to laser at a desired value of the output power selected along a mono tonic function of the injection current. | 04-15-2010 |
20100040382 | DISPERSION TOLERANT OPTICAL SYSTEM AND METHOD - An optical communication system and method of use are described. The system comprises an optical source adapted to receive a digitally encoded data signal comprising sequences of data at a data rate (B) and comprising two signal levels representing a first state and a second state of the data signal, the optical source being adapted to produce an optical signal substantially frequency modulated with frequency excursion Δν comprising a first instantaneous frequency (ν | 02-18-2010 |
20090252188 | Misalignment Prevention in an External Cavity Laser Having Temperature Stabilisation of the Resonator and the Gain Medium - The present invention relates to an external-cavity laser module comprising a thermoelectric cooler (TEC) including an upper carrier plate having an upper surface, said TEC being configured to stabilise the temperature of the upper surface at a substantially constant temperature. The laser module further comprises a laser assembly mounted on an optical bench, which is in thermal coupling with said upper surface, said laser assembly comprising a gain medium for emitting an optical beam into the external cavity and an end mirror. | 10-08-2009 |