Abstract: An optical arrangement includes a plurality of planar substrates with at least one planar integrated optical waveguide on each planar substrate. At least one optical waveguide structure has at least one end connected via an optical connecting structure to one of the planar integrated optical waveguides. The optical waveguide structure is positioned at least partly outside the integration plane for the planar integrated optical waveguide and a refractive index contrast between a core region and a cladding region of the optical waveguide structure is at least 0.01.

Abstract: In an integrated optical circuit, light from a light source is polarized and coupled to a first and second strip waveguide. A waveguide coupling element couples the two optical signals from the two strip waveguides to different polarization modes of an optical fiber line. The optical fiber line is connected to a measuring head, which reflects the optical signal and in which a phase difference between the two optical partial signals is modulated in a magnetic field. In the waveguide coupling element, the reflected signal is split into two optical partial signals having the same polarization and the phase difference between the two partial signals is determined. A phase modulator device provides for closed-loop operation. Compared to fiber-optical concepts, the number of splices is reduced.

Abstract: An optical arrangement includes a plurality of planar substrates with at least one planar integrated optical waveguide on each planar substrate. At least one optical waveguide structure has at least one end connected via an optical connecting structure to one of the planar integrated optical waveguides. The optical waveguide structure is positioned at least partly outside the integration plane for the planar integrated optical waveguide and a refractive index contrast between a core region and a cladding region of the optical waveguide structure is at least 0.01.

Abstract: A method for making optical connections with optical waveguides includes mounting the optical waveguides or a device comprising the optical waveguides, on a component carrier. A partial region of the optical waveguides is embedded in a volume of resist material. Positions of the optical waveguides to be connected are detected with reference to a coordinate system using a measuring system. Favorable, three-dimensional geometries are determined for optical waveguide structures for connecting the optical waveguides to each other at predetermined connecting locations and the optical waveguide structure geometries are converted to a machine-readable dataset. The optical waveguide geometries in the volume of the resist material are three-dimensionally structured using a direct-writing lithography device operating on the basis of the machine-readable dataset.

Abstract: An electro-optical device for processing an optical signal, comprises an electrode that is arranged and designed so that the optical signal at least partially intrudes the electrode when the optical signal is processed in the electro-optical device. An insulator is arranged adjacent to the electrode so that one face of the electrode contacts the insulator. A gate is arranged so that a voltage is applicable between the electrode and the gate such that a charge layer is induced on the face of the electrode that is contacting the insulator.

Abstract: An optical detector for detecting an optical signal beam (OSB) modulated in a way that it includes an in-phase and/or a quadrature component, includes: a polarisation beam splitter arranged to split the OSB into two polarised OSBs; a non-polarisation beam splitter arranged to further split each of the two polarised OSBs into two split polarised OSBs; at least one birefringent element providing a phase shift, the birefringent element being arranged in a path of at least one polarised OSB and/or in a path of at least one split polarised OSB so that an in-phase and quadrature phase offset between two split polarised OSBs originating from the same polarised OSB is formed in output signal beams; and at least two detection means arranged to receive at least one output signal beam that includes a in-phase and/or quadrature component of the OSB.

Abstract: An optical device having a semiconductor optical amplifier (SOA) coupled to an optical filter, which device may be used for optical performance monitoring. One embodiment of the invention provides an optical regenerator/monitor (RM), in which an SOA is used both for optical regeneration of a communication signal applied to the RM and for evaluation of the quality of that signal. The RM has (i) a 2R regenerator, which includes the SOA and an optical filter, and (ii) a relatively simple signal processor configured to receive optical signals from two or more sampling points located at the regenerator. In one configuration, the processor evaluates the quality of the communication signal by comparing optical power tapped from the input and output of the regenerator. The RM, so configured, can be used, for example, to monitor chromatic dispersion and/or optical noise in the communication signal.

Abstract: The specification describes an optical pulse generator in a return-to-zero format in which a phase-modulated (PM) optical signal is converted to intensity-modulated (IM) optical pulses using chromatic dispersion. Compared with Mach-Zehnder-modulator-based pulse generators, this scheme is potentially more efficient (lower insertion loss). The pulse generator of the invention is suitable for very high data rates, e.g. 40 Gb/s. The structure of the pulse generator is a phase-modulated pulse source combined with a dispersive element having the required dispersion.

Abstract: Systems and techniques for generating optical pulses exhibiting a progressive phase shift, and the use of those pulses to transmit data, are described. One embodiment of the invention employs a Mach-Zehnder modulator using electrical signals chosen to introduce a predetermined frequency shift at the center of each pulse generated by the pulse generator. This frequency shift is achieved by introducing a timing difference between the electrical input signals. Another embodiment of the invention employs a chirp free pulse generator and a separate phase modulator to induce the desired frequency or phase shift. These progressively phase shifted pulses may be further modulated to transmit data by introducing phase or amplitude modulation on the optical pulses, depending on the data to be transmitted.

Abstract: A method and apparatus for providing optical 3R regeneration involving: 1) generating an encoded optical clock signal from at least an optical signal; 2) introducing the encoded clock signal into a delay interference section of a regenerator such that an amplitude modulated clock signal is produced; andoutputting the amplitude modulated clock signal wherein the output amplitude modulated clock signal preserves information present within the input optical signal.

Abstract: An optical filter apparatus for processing an optical signal comprising a spectrum broadening device for spectrally dividing one or more channels of the optical signal into a discrete set of spectral components for each channel, a collector for collecting the spectral components on a discrete number of corresponding light channels, one or more processors for individually processing one or more of the spectral components on the light channels, and a combiner for recombining the spectral components on the light channels.

Abstract: An optical device having a semiconductor optical amplifier (SOA) coupled to an optical filter, which device may be used for optical performance monitoring. One embodiment of the invention provides an optical regenerator/monitor (RM), in which an SOA is used both for optical regeneration of a communication signal applied to the RM and for evaluation of the quality of that signal. The RM has (i) a 2R regenerator, which includes the SOA and an optical filter, and (ii) a relatively simple signal processor configured to receive optical signals from two or more sampling points located at the regenerator. In one configuration, the processor evaluates the quality of the communication signal by comparing optical power tapped from the input and output of the regenerator. The RM, so configured, can be used, for example, to monitor chromatic dispersion and/or optical noise in the communication signal.

Abstract: Systems and techniques for generating optical pulses exhibiting a progressive phase shift, and the use of those pulses to transmit data, are described. One embodiment of the invention employs a Mach-Zehnder modulator using electrical signals chosen to introduce a predetermined frequency shift at the center of each pulse generated by the pulse generator. This frequency shift is achieved by introducing a timing difference between the electrical input signals. Another embodiment of the invention employs a chirp free pulse generator and a separate phase modulator to induce the desired frequency or phase shift. These progressively phase shifted pulses may be further modulated to transmit data by introducing phase or amplitude modulation on the optical pulses, depending on the data to be transmitted.

Abstract: A delayed interference all-optical wavelength converter is arranged to convert and reshape a pulsed input signal Pin at &lgr;1 into the wavelength converted signal Pconv at &lgr;2, where &lgr;1 and &lgr;2 are different. A delayed interference all-optical wavelength regenerator is similar, but is arranged to reshape a pulsed input signal Pin into the wavelength converted signal Pconv, where the wavelengths of the input signal and the converted signal are the same. The converter/regenerator comprises an input-signal coupling unit for receiving the pulsed input signal and supplying it to one input of a modulation section, the other input to which is a carrier signal Pcw. The output of the modulation section Pint, which is generally speaking, a phase modulated signal which may also have an amplitude modulated component, is applied to a delay interference section arranged to transform Pint into a primarily amplitude-modulated signal.

Abstract: An optical transmitter is disclosed including a laser source, a modulator for generating a differential phase shift keyed signal, and a delay interferometer having at least one optical input and at least one optical output. The delay interferometer is adapted to provide a time delay of about one bit period. Also disclosed is a method of transmitting alternate mark inversion and/or duobinary signals. The method includes the steps of providing a differential phase shift keyed signal, inputting the differential phase shift keyed signal into a delay device adapted to split the differential phase shift keyed signal into at least two signals on at least two arms and to delay the signal on at least one arm by about one bit period, and coherently combining the signals on the arms to produce alternate mark inversion and/or duobinary signals.

Abstract: An optical filter apparatus for processing an optical signal comprising a spectrum broadening device for spectrally dividing one or more channels of the optical signal into a discrete set of spectral components for each channel, a collector for collecting the spectral components on a discrete number of corresponding light channels, one or more processors for individually processing one or more of the spectral components on the light channels, and a combiner for recombining the spectral components on the light channels.

Abstract: In accordance with the invention, a train of RZ or CSRZ pulses is produced by passing phase modulated laser light through a delay interferometer. The parameters of the phase modulation and the delay interferometer are calculated from the desired pulse train characteristics (e.g. repetition rate, RZ or CSRZ, duty cycle). A directly modulated CW laser, or a CW laser followed by a phase modulator, produces the constant amplitude, phase modulated light. The phase modulated signal is split into two paths. One signal path is delayed with respect to the other by the calculated delay. The signals are recombined in an optical coupler to produce an RZ pulse train and/or a CSRZ pulse train.

Abstract: The specification describes an optical pulse generator in a return-to-zero format in which a phase-modulated (PM) optical signal is converted to intensity-modulated (IM) optical pulses using chromatic dispersion. Compared with Mach-Zehnder-modulator-based pulse generators, this scheme is potentially more efficient (lower insertion loss). The pulse generator of the invention is suitable for very high data rates, e.g. 40 Gb/s. The structure of the pulse generator is a phase-modulated pulse source combined with a dispersive element having the required dispersion.

Abstract: In accordance with the invention, a train of RZ or CSRZ pulses is produced by passing phase modulated laser light through a delay interferometer. The parameters of the phase modulation and the delay interferometer are calculated from the desired pulse train characteristics (e.g. repetition rate, RZ or CSRZ, duty cycle). A directly modulated CW laser, or a CW laser followed by a phase modulator, produces the constant amplitude, phase modulated light. The phase modulated signal is split into two paths. One signal path is delayed with respect to the other by the calculated delay. The signals are recombined in an optical coupler to produce an RZ pulse train and/or a CSRZ pulse train.

Abstract: A wavelength converter with a monolithically integrated delay loop in a delayed interference configuration that needs only one SOA or other non-linear optical element coupled to the input fiber, a first coupler arranged to split the output of the SOA or other non-linear optical amplifying element into two paths having controllable delay and phase shift characteristics, and at least one output coupler to combine the signals present on the two paths to provide the converter output. One embodiment of the invention has a monolithically integrated delay loop utilizing one or more asymmetric couplers. Another embodiment of the invention has a coupler that does not require an asymmetric splitting ratio, and has either a gain element in one of the paths, an attenuation element in one of the paths, or both.