Abstract: The present disclosure relates to an imaging system comprising an impulsion light source for an input light beam oriented toward an observed area and an optoelectronic sensor having a photosensitive surface with a visibility capable of substantially covering the observed area. An impulsion of the incident light beam is backscattered by only by a portion of the observed area into a backscattered spot on the photosensitive surface. A deflection device deflects the impulsions of the incident light beam onto the respective portions of the observed area. A device acquires the thumbnail images corresponding to the backscattered spots resulting in impulsions of the incident light beam. The system combines said thumbnail images to produce an image having a sufficiently high signal-to-noise ratio for portions of interest of the observed area, a high spatial resolution, and a greater insensitivity to motion blurs.

Abstract: The present disclosure relates to an imaging system comprising an impulsion light source for an input light beam oriented toward an observed area and an optoelectronic sensor having a photosensitive surface with a visibility capable of substantially covering the observed area. An impulsion of the incident light beam is backscattered by only by a portion of the observed area into a backscattered spot on the photosensitive surface. A deflection device deflects the impulsions of the incident light beam onto the respective portions of the observed area. A device acquires the thumbnail images corresponding to the backscattered spots resulting in impulsions of the incident light beam. The system combines said thumbnail images to produce an image having a sufficiently high signal-to-noise ratio for portions of interest of the observed area. a high spatial resolution, and a greater insensitivity to motion blurs.

Abstract: The invention relates to a very broad band wavelength multiplexed transmission system, typically having a bandwidth greater than 150 nm or 200 nm, and in which energy transfers between channels caused by the Raman effect are compensated. The depletion of channels at shorter wavelengths is compensated by amplification which is preferably distributed, while the enrichment of channels at longer wavelengths is compensated by attenuation.

Abstract: A method of dynamically adjusting an optical module in an optical system including a plurality of transmission channels includes the following steps: measuring the quality of the optical signal at the output of the system as defined by an error function, varying an optical parameter of at least one module of the system, measuring a differential error introduced by each variation on the error function of the optical signal at the output of the system, estimating an operating point of the system corresponding to an expected reduction of the error function, and adjusting a parameter of an optical module toward the operating point of the system.

Abstract: The present invention provides a WDM optical communication system, comprising input means and output means for an optical signal, an optical fibre path connecting signal-transmissively said input and output means, wherein the optical signal is amplified by means of Raman amplification and said optical fibre path comprises at least one Raman amplifier, further comprising WDM means for coupling at least two polarized pump radiation wavelengths with wavelengths less than the signal radiation wavelength into said Raman amplifier, wherein one pump radiation wavelength has a selected different polarization with respect to the polarization of the other pump radiation wavelengths.

Abstract: The present invention relates to a method for the modulation of the signal power in optical transmission systems comprising an optical amplification device. Also a method for the detection of bit errors in the processing of digitalized transmitted data is disclosed whereby the data are transmitted by an optical transmission system.

Abstract: A four-port optical circulator has two planar lightwave circuit polarisation beam splitters (40, 54). Two ports of the circulator are formed by two input ports (32, 36) of the first splitter (40). The two other ports of the circulator are formed by two input ports (34, 38) of the second splitter (56). The circulator further has an assembly of a wave plate (46) and a Faraday rotator (48). A first light path through this assembly connects a first output port (42) of the first splitter (40) and a first output port (50) of the second splitter (54). A second light path through the assembly connects a second output port (44) of the first splitter (40) and a second output port (52) of the second splitter (54). The circulator is easy to integrate into a planar lightwave circuit. It may also be used as isolator.

Abstract: A method of dynamically adjusting at least one optical module in an optical system including a plurality of transmission channels includes the following steps:

Abstract: The present invention relates to a method for the modulation of the signal power in optical transmission systems comprising an optical amplification device. Also a method for the detection of bit errors in the processing of digitalized transmitted data is disclosed whereby the data are transmitted by an optical transmission system.

Abstract: The present invention provides an optical fiber Raman amplifier comprising input means and output means, an optical fiber path connecting signal-transmissively said input and output means, wherein said optical fiber path comprises a plurality of single stage Raman amplifiers, further comprising means for coupling at least one pump wavelength having a shorter wavelength than a signal wavelength into each single stage Raman amplifier, wherein each single stage Raman amplifier has an individual local gain curve, wherein the local gain curves of teh single stage Raman amplifiers are selected to provide an overall flat gain curve.

Abstract: The present invention provides an optical fiber amplifier comprising input means and output means, an optical fiber path connecting signal-transmissively said input and output means, wherein said optical fiber path comprises a Raman fiber amplifier and a rare-earth-doped fiber amplifier, wherein said Raman fiber amplifier and said rare-earth-doped fiber amplifier are set in a serial arrangement, whereby the Raman amplification fiber and the rare-earth-doped fiber are pumped by the same pump wavelength. Furthermore the present invention provides an optical fiber communication system comprising said optical fiber amplifier.

Abstract: The present invention provides a WDM optical communication system, comprising input means and output means for an optical signal, an optical fibre path connecting signal-transmissively said input and output means, wherein the optical signal is amplified by means of Raman amplification and said optical fibre path comprises at least one Raman amplifier, further comprising WDM means for coupling at least two polarized pump radiation wavelengths with wavelengths less than the signal radiation wavelength into said Raman amplifier, wherein one pump radiation wavelength has a selected different polarization with respect to the polarization of the other pump radiation wavelengths.