Abstract: An optical demultiplexer (13, 30) for wavelength division multiplex WDM optical radiation comprising a plurality of wavelength channels (Ch1 . . . Ch16) spaced over a wavelength spectrum said demultiplexer being for separating the WDM radiation into individual wavelength channels is described. The demultiplexer comprises a first demultiplexer (12) for dividing the W-DM radiation into a plurality of sub-bands (Ch1 . . . Ch4, Ch5 . . . Ch8, Ch9 . . . Ch12, Ch13 . . .

Abstract: A method of piloting an optical polarization controller including a cascade of variable polarization transformers that can be driven individually to realize overall a polarization transformation between an input optical signal and an output optical signal with each transformer having predetermined maximum and minimum end driving limits. For each transformer the method includes cyclically the steps of finding an error signal output to the controller and driving a first transformer polarization variation by a predetermined amount CS in one of the two directions to check whether with this variation the error signal is reduced and, if not, driving in the opposite direction. The decision of which of the two directions to drive first is made each time and is not fixed. Equipment in accordance with the method is also described.

Abstract: A method of piloting an optical polarization controller including a cascade of variable polarization transformers that can be driven individually to realize overall a polarization transformation between an input optical signal and an output optical signal with each transformer having predetermined maximum and minimum end driving limits. For each transformer the method includes cyclically the steps of finding an error signal output to the controller and driving a first transformer polarization variation by a predetermined amount CS in one of the two directions to check whether with this variation the error signal is reduced and, if not, driving in the opposite direction. The decision of which of the two directions to drive first is made each time and is not fixed. Equipment in accordance with the method is also described.

Abstract: An optical demultiplexer (13, 30) for wavelength division multiplex WDM optical radiation comprising a plurality of wavelength channels (Ch1 . . . Ch16) spaced over a wavelength spectrum said demultiplexer being for separating the WDM radiation into individual wavelength channels is described. The demultiplexer comprises a first demultiplexer (12) for dividing the W-DM radiation into a plurality of sub-bands (Ch1 . . . Ch4, Ch5 . . . Ch8, Ch9 . . . Ch12, Ch13 . . .

Abstract: The present invention relates to a shelf for holding printed circuit boards; the shelf comprises a first frame and a second frame, adapted to hold printed circuit boards, and a panel provided with two opposite sides, wherein the first frame is mounted on a first of the two sides and the second frame is mounted on a second of the two sides; the shelf comprises further cooling means adapted to generate an airflow for cooling the printed circuit boards held by the first frame and deflecting means adapted to deflect at least part of said airflow for cooling the printed circuit boards held by the second frame.

Abstract: A resonant optical modulator includes an electro-optical substrate, an optical waveguide formed in the substrate and having a variable index of refraction, and an active modulator electrode formed on the substrate in relation to the waveguide to effect electro-optical variation of the index of refraction upon application to the electrode of a modulating signal. An interface port formed on the substrate provides the modulating signal to the electrode from a signal source and has an impedance. An electrical structure, formed on the substrate and coupled to the interface port and the electrode, makes an impedance of the optical modulator substantially equal to the impedance of the signal source. The electrical structure includes a delay line and a stub formed on the substrate.

Abstract: A resonant optical modulator includes an electro-optical substrate, an optical waveguide formed in the substrate and having a variable index of refraction, and an active modulator electrode formed on the substrate in relation to the waveguide to effect electro-optical variation of the index of refraction upon application to the electrode of a modulating signal. An interface port formed on the substrate provides the modulating signal to the electrode from a signal source and has an impedance. An electrical structure, formed on the substrate and coupled to the interface port and the electrode, makes an impedance of the optical modulator substantially equal to the impedance of the signal source. The electrical structure includes a delay line and a stub formed on the substrate.

Abstract: A resonant optical modulator includes an electro-optical substrate, an optical waveguide formed in the substrate and having a variable index of refraction, and an active modulator electrode formed on the substrate in relation to the waveguide to effect electro-optical variation of the index of refraction upon application to the electrode of a modulating signal. An interface port formed on the substrate provides the modulating signal to the electrode from a signal source and has an impedance. An electrical structure, formed on the substrate and coupled to the interface port and the electrode, makes an impedance of the optical modulator substantially equal to the impedance of the signal source. The electrical structure includes a delay line and a stub formed on the substrate.