58 results about "Optical interleaver" patented technology

An optical interleaver comprising: an interferometer which includes a coupler, a first phase shifter and a combiner; wherein the coupler splits incident light into a first light beam and a second light beam and couples the first light beam and the second light beam to the first phase shifter; wherein the first phase shifter includes a first light propagation element that propagates the first light beam along a first path between the coupler and the combiner and that includes a second light propagation element that propagates the second light beam along a second path between the coupler and the combiner, the first and second paths having different path lengths that contribute to a phase shift between light of the first light beam propagated along the first path and light of the second light beam propagated along the second path; wherein the combiner couples the first light beam with and the second light beam; a second phase shifter which receives first light beam light propagated along the first path between the coupler and the combiner and imparts a first wavelength dependent variation in phase to the received first light beam light; a third phase shifter which receives second light beam light propagated along the second path between the coupler and the combiner and imparts a second wavelength dependent variation in phase to the received second light beam light.

ROADM node systems and methods of operation are disclosed. ROADM node systems may include transponder aggregators including transponders to add signals for switching through the ROADM node. The transponder aggregators include optical couplers constrained that are from coupling added signals on adjacent channels for simultaneous use. The ROADM system may include an optical interleaver that can provide an additional filtering function for the coupled signals prior to transmission of the signals on a WDM network.

A reconfigurable optical interleaver/deinterleaver device combines/separates a pair of optical input signals from and/or to an optical WDM input signal. The interleaver device includes a spatial light modulator having a micro-mirror device with a two-dimensional array of micro-mirrors that flip between first and second positions in a “digital” fashion in response to a control signal provided by a controller in accordance with a switching algorithm and an input command. A pair of collimators, diffraction gratings and Fourier lens collectively collimate, separate and focus the optical input channels and optical add channels onto the array of micro-mirrors. Each optical channel is focused on a plurality of micro-mirrors of the micro-mirror device, which effectively pixelates the optical channels.

An apparatus includes an interleaver configuration for at least one of combining or separating odd and even channel groups to achieve channel density doubling; and an optical equalizer for suppressing inter symbol interference within the channels to provide intra-channel equalizing in the optical path, the equalizer being integrated into the interleaver. Preferably, optical equalizer and interleaver are integrated together as a single monolithic device, the optical equalizer includes a passband that has a dip in the channel center to achieve a raised-cosine filtering profile in the optical signal path to achieve inter-symbol interference ISI suppression, and the equalizer includes integration into the optical path of the interleaver to realize a monolithic device combining or separating odd and even channel groups to achieve channel density doubling. Preferably, also, the optical equalizer includes a first equalizer with half the depth of required ripple dips at both a first output port and an input port and a second equalizer with half the depth of required ripple dips at a second output port.

An optical interleaver for use in a range of telecommunications applications including optical multiplexers/demultiplexers and optical routers. The optical device includes an optical processing loop which allows multi-stage performance characteristics to be achieved with a single physical filtration stage. Optical processing on the first leg and second legs of the loop is asymmetrical thereby improving the integrity of the optical signals by effecting complementary chromatic dispersion on the first and second legs. A fundamental filter cell within the interleaver filters optical signals propagating on each of the two legs of the optical loop which intersects the fundamental filter cell.

An optical add/drop multiplexer (OADM) having reduced crosstalk is disclosed. The OADM uses an optical interleaver to separate channels of a wavelength division multiplexed signal into a plurality of branches. The branches then separately act on the widely spaced channels to add or drop channels. After the add/drop function is completed, the channels on the branches are recombined.

Systems and methods for data transport, including submarine reconfigurable optical add/drop multiplexers, branching units configured to receive signals from trunk terminals (TTs), and dummy light filters configured to pass useful signals through the filters, and to reflect dummy light. Optical interleavers are configured to separate useful signals into two or more groups of optical channels, and the optical channels are set to a frequency of either a left or a right portion of a total channel bandwidth. De-interleavers merge signal groups together from trunk terminals, and lasers at each of the transponders at the source terminals are configured to adjust a destination of a channel by fine tuning a frequency or wavelength of the one or more signals.

An optical bypass element for an optical communication system. The optical bypass element, formed of an optical interleaver, is positioned in parallel with a regenerator. Data requiring regeneration is caused to be provided to the regenerator while data not requiring regeneration is bypassed about the regenerator by way of the optical bypass element. Once bypassed around the regenerator and once regenerated at the regenerator, the respective data is recombined and subsequently routed to communication endpoints.

Provided is an all-optical gain-clamped fiber amplifier, comprising transmission and isolation means for periodically transmitting an optical signal or reflecting amplified spontaneous emission (ASE) back to a gain medium. The transmission and isolation means can be embodied by an optical interleaver or a number of optical fiber Bragg gratings. Accordingly, an optical signal can be amplified across the entire C-band, and an ASE reflector-based gain-clamped fiber amplifier having a wider dynamic range than conventional amplifiers can be implemented.

Optical interferometers with variable dispersion are shown. These interferometers are useful as optical interleavers and through the control of their design, are made to have negative and near-zero dispersion. The N-type interleaver has a negative dispersion slope near the center of the pass band. The Z-type interleaver has a dispersion that is close to zero within the pass band. These interleavers can be arranged in various systems to produce low dispersion optical networks. The non-linear phase etalons in the N- and Z-type interleavers taught herein contribute to the device dispersion. The N-Type interleaver includes a linear cavity length that is 1.5 times that of a non-linear cavity. The Z-type interleaver includes two non-linear cavities that are out of phase with each other such that the net dispersion is close to zero.

An optical interleaver for use in a range of telecommunications applications including optical multiplexers/demultiplexers and optical routers. The optical device includes an optical processing loop which allows multi-stage performance characteristics to be achieved with a single physical filtration stage. Optical processing on the first leg and second legs of the loop is asymmetrical thereby improving the integrity of the optical signals by effecting complementary chromatic dispersion on the first and second legs. A fundamental filter cell within the interleaver filters optical signals propagating on each of the two legs of the optical loop which intersects the fundamental filter cell.

The invention discloses a one-dimensional membrane cavity structure-based different-bandwidth optical interleaver. The interleaver comprises an input optical fiber, a collimating lens, eleven optical dielectric layers, a focusing lens and an output optical fiber and is characterized in that: along the forward direction of a light beam, the eleven optical dielectric layers orderly comprise: a first layer and an eleventh layer of B-type dielectric layers, a second layer and a tenth layer of C-type dielectric layers, a third layer and a ninth layer of the B-type dielectric layers, a fourth layer and an eighth layer of A-type dielectric layers, a fifth layer and a seventh layer of D-type dielectric layers and a sixth layer of a C-type dielectric layer; the C dielectric layers are isotropical optical glass; the A, B and D dielectric layers are optical thin films with different refractive indexes; the optical thicknesses of the A, B and D dielectric layers are all 1/4 of a central wavelength; and the expression of the optical thickness of the C dielectric layer is C/(2*delta f). The interleaver has the characteristics of low cost, high performance and high reliability; and both a pass band and a stop band have flat filter characteristics, so the interleaver is used for performing the selection of wavelength signals, noise filter of an optical amplifier, gain equalization and the like in a wave division multiplex communication system.

The cavity in the mirror arm of a conventional interleaver is replaced by a wedge integral with the beamsplitter structure of the interleaver. Thus, the light reflected from the AR-coated surface of the wedge is dispersed away from the optics of the device. The beam emerging from the wedge surface is directed toward a tilted mirror that reflects it totally on-axis. As a result of the diversion of the light reflected from the wedge surface and the non-parallel disposition of the wedge surface with respect to the mirror, phase errors are virtually eliminated. In another embodiment, a second wedge is used with a second antireflective surface disposed in parallel to the first wedge's antireflective surface, and with a mirror normal to the optical axis of the device.

Consistent with the present disclosure optical interleaver and deinterleaver circuits are integrated onto a substrate. The inputs to the interleaver and the outputs of the deinterleaver are each coupled to a corresponding variable optical attenuator (VOA) and optical tap, which are also provided on the substrate. The optical taps supply a portion of the output of each VOA to a corresponding photodetector. A control circuit, which is coupled to the photodetector, in turn, supplies a control signal to each VOA based on the output of the photodetector. Accordingly, optical multiplexing and demultiplexing components, as well as monitoring and power regulating components are provided on the same chip. Such a chip may be compact, relatively inexpensive, and has reduced power consumption compared to optical multiplexer and demultiplexer equipment including discrete components.

A method includes modulating lightwaves to provide first and second OFDM signal sidebands at a first polarization direction and first and second OFDM signal sidebands at a second polarization direction, and combining sidebands that are oppositely positioned and joined from the first and second OFDM signal sidebands at each polarization direction to provide a polarization multiplexing OFDM signal.

A light source includes a first set of first beam sources having parallel output beams lying in a first-beam-source plane and a second set of second beam sources having parallel output beams lying in a second-beam-source plane. The first-beam-source output beams are parallel to the second-beam-source output beams, but are spatially offset in a direction perpendicular to the first-beam-source output beams. A spatial optical interleaver disposed receives the first-beam-source output beams and the second-beam-source output beams. The first-beam-source output beams pass unimpeded through a set of first-beam openings in the spatial optical interleaver, and the second-beam-source output beams are reflected parallel to the first-beam-source output beams and in the first-beam-source plane.

An optical system for providing all-optical up-conversion of a baseband signal including an all-optical up-converter responsive to baseband signals to provide corresponding dual sideband signals about a suppressed optical carrier, said dual sideband signals each having the same polarization direction, being phase locked, having the same optical power and having a fixed frequency spacing; and an optical filter for filtering the carrier signals and providing wavelength division multiplexed signals without optical carriers. In a preferred embodiment, the all-optical up-converter includes an intensity modulator for generating two pump lightwaves that are carrier suppressed in response to the intensity modulator receiving a laser light source and being driven by an RF signal, wherein the intensity modulator is DC biased at a null point, an optical combiner for combining the baseband signal and the two pump lightwaves, a nonlinear medium for four wave mixing the baseband signal and two pump lightwaves to generate the baseband signal and corresponding dual sideband signals, and an optical interleaver for removing the baseband signal and two pump lightwaves to provide said sideband signals about the suppressed optical carrier.

A method and apparatus is provided for reformatting or interleaving a WDM signal that includes a plurality of optical channels having a first bandwidth and a first channel spacing. The method begins by receiving the WDM signal and dividing it into first and second subsets of optical channels each having a second channel spacing. Next, the first subset of optical channels are divided into third and fourth subsets of optical channels each having a third channel spacing. In addition, the second subset of optical channels is divided into fifth and sixth subsets of optical channels each having a fourth channel spacing. The third and fifth subsets of optical channels are combined to generate a first output WDM signal, while the fourth and sixth subsets of optical channels are combined to generate a second output WDM signal.

The invention discloses an optical interleaver with adjustable high speed isolation and centre wavelength. A single optical fiber collimator, a first polarization displacement crystal, a first half wave plate group, a first electro light delay plate, a quarter-wave plate, a double refraction crystal, a second half wave plate group, a second electro light delay plate, a third half wave plate group, a second polarization displacement crystal, a fourth half wave plate group, a ridge prism, a third polarization displacement crystal and a double optical fiber collimator are sequentially put in the direction of the same horizontal optical path; parallel beams separated by the second polarization displacement crystal are collimated by the fourth half wave plate group, the ridge prism, the third polarization displacement crystal and coupled to the double optical fiber collimator; the high speed adjustment of the channel separation of the optical interleaver is realized by controlling the first electro light delay plate; the high speed adjustment of the centre wavelength of the optical interleaver is realized by controlling the second electro light delay plate. The invention realizes the high speed adjustment of the isolation and the centre wavelength of the optical interleaver, and is characterized by the compact structure, the low cost, the stable performance, etc.

The invention relates to a one-dimensional film-cavity type unequal bandwidth optical interleaver design method at any duty ratio. The structure is formed by cascading the dielectric cavities with the multilayer films vapor-deposited on the left and right sides. The multilayer film structure between the dielectric cavities is equivalent to be a reflector to obtain a simplified structure of a multi-cavity reflector cascading structure. z transformation of a digital signal processing theory is introduced to obtain a reflection transmission function expression of the simplified structure, and on this basis, through the combination with the Butterworth digital filter design method, the optimal reflection coefficient of each reflector can be obtained by means of a genetic algorithm. At the end, the multilayer film structure between the dielectric cavities is constructed based on the optimal reflection coefficient to realize the design of the one-dimensional film-cavity type unequal bandwidth optical interleaver. The method is simple by means of the mature digital filter design method, and the designed one-dimensional film-cavity type unequal bandwidth optical interleaver is simple in structure and easy to manufacture in actual condition; and moreover, the optical interleaver at any duty ratio can be designed, and the output spectrum with high flatness characteristic can be obtained.