140 results about "Mode transformation" patented technology

The invention relates to a compact polarization rotation beam splitter, which comprises an input waveguide, a mode conversion region, a mode coupling region and an output waveguide, a TM0 mode optical signal in the optical signals is converted into a TE mode high-order optical signal in the mode conversion area; the mode coupling region is used for coupling the TE mode high-order optical signal into a TE0 mode optical signal with the first adiabatic coupling waveguide; and the output waveguide is used for outputting a TE0 mode optical signal which is not subjected to mode conversion in the optical signals, and outputting a TE0 mode optical signal obtained after mode conversion of the mode conversion area and the second adiabatic coupling waveguide. According to the invention, the polarization rotation path can be shortened through high-order mode conversion in the mode conversion area, efficient beam splitting is realized by using the asymmetric adiabatic coupling waveguide in the mode coupling area, the size reduction of a redundant structure is avoided through function integration, the performance of the beam splitter is ensured, and the problems of large size and low cost of the existing polarization rotation beam splitter are solved. And the performance is not good.

The invention provides a fault positioning method and system for an overhead line of a power distribution network, and a storage medium. The method comprises the steps of obtaining a plurality of fault traveling wave magnetic field signals; performing the following steps on any signal: performing phase-mode transformation on the signal, extracting and decomposing a line mode component, determining a modulus maximum point, and determining the time corresponding to the point as a first fault traveling wave head arrival moment; carrying out clock synchronization on the moment, and obtaining a wave head arrival moment of a second fault traveling wave; obtaining a to-be-detected fault point and a line parameter; based on the wave head arrival moments of the plurality of second fault traveling waves, extracting a head end arrival moment and a tail end arrival moment; and performing fault positioning on the overhead line of the power distribution network based on the head end arrival time, the tail end arrival time and the fault line parameters. According to the fault positioning method for the overhead line of the power distribution network, interference to normal operation of the power distribution network can be avoided, and high-precision non-intrusive positioning of the overhead line of the power distribution network is realized through the tunneling magnetoresistive sensor.

The invention relates to a high-order transverse mode compression state preparation device based on optical parameter resonant cavity mode selection, and belongs to the technical field of quantum state light field generation. Fundamental frequency light and pump light output by the laser source generate a high-order transverse mode light field through the mode conversion module, and then the high-order transverse mode light field enters the optical parametric resonant cavity to be subjected to parametric down-conversion with the nonlinear crystal. The cavity length of the optical parametric resonant cavity is locked at the optimal pumping mode position corresponding to the high-order transverse mode compression state, so that resonance of an impurity mode in the optical parametric resonant cavity can be avoided, and the compression level of a high-order transverse mode light field is improved. Under injection of high-order transverse mode pump light, the pump mode is purified through the optical parametric resonant cavity of the annular structure, the compression level of a high-order transverse mode light field is enhanced, adjustment is easy, practicability is high, productization is easy, and wide application prospects are achieved in the fields of quantum space measurement, biological measurement, atomic force microscope detection and the like.

The invention relates to the technical field of tunneling equipment, in particular to a mode conversion system of a multi-mode shield tunneling machine in a composite stratum, which comprises a prediction layer, a sensing layer, a data bus layer, a decision-making layer and an execution layer: the prediction layer acquires front geological and hydrological information through TSP advanced geological forecast and an infrared water detector; the sensing layer integrates multiple sensors to collect tunneling parameters, and the tunneling parameters are processed through a data fusion algorithm; the data bus layer realizes data space-time alignment based on a distributed stream processing platform; the decision-making layer adopts a CNN + fuzzy logic + reinforcement learning hybrid model to generate a conversion instruction; and the execution layer drives an execution mechanism to complete EPB / SPB / TBM mode conversion, and safety is guaranteed through feedback correction. According to the method, adaptive decision making and seamless execution of mode conversion are achieved, the conversion time is remarkably shortened, tool abrasion is reduced, and the construction efficiency and safety of the composite stratum are improved.

A photonics device including a waveguide and an index smoothing structure is described. The waveguide is configured to carry an optical signal and includes a thin film lithium-containing electro-optic (TFLCEO) material. The waveguide has a first portion, a transition portion, and a second portion. The optical signal has a first mode in the first portion and a second mode in the second portion. The transition portion transfers the optical signal between the first portion and the second portion and transitions between the first mode and the second mode. The index smoothing structure corresponds to the transition portion. The index smoothing structure is configured to transition a first effective index of refraction for the first mode to a second effective index of refraction for the second mode. The index smoothing structure having an intermediate effective index of refraction.

The invention discloses a broadband polarization rotation beam splitter based on a thin-film lithium niobate platform, an LN ridge waveguide structure is prepared on the thin-film lithium niobate platform, and the broadband polarization rotation beam splitter comprises five parts: two gradually-changed conical structures, a straight waveguide, an S bend, a phase shifter and a 2 * 2MMI coupler based on general interference. For TM0 input, a TM0 mode is converted into a TE1 mode through a conical structure, and then the TM0 mode is divided into two TE0 modes with the phase difference being pi; for TE0 input, the TE0 mode is kept unchanged and is divided into two TE0 modes with the phase difference of 0; under the two conditions, a phase difference of pi / 2 is introduced before multimode interference, and for TE0, the phase difference is pi / 2, so that the TE0 is output from CH2, and crosstalk in CH1 is minimized; for TM0, the phase difference is-pi / 2, resulting in the output of TM0 from CH1, minimizing crosstalk in CH2. According to the invention, mode conversion and polarization beam splitting are realized in a compact size.

The invention discloses a polarization rotator and a manufacturing method thereof. The polarization rotator comprises a first waveguide, a first coupling waveguide, a mode conversion waveguide, a second coupling waveguide and a second waveguide which are sequentially connected in a first direction, the first waveguide is used for introducing external first mode polarized light; the first coupling waveguide is used for coupling the first waveguide and the mode conversion waveguide; the mode conversion waveguide is used for converting the first mode polarized light guided by the first waveguide into second mode polarized light, and the mode conversion waveguide has geometric asymmetry in a first direction; the second coupling waveguide is used for coupling the mode conversion waveguide and the second waveguide; the second waveguide is used for exporting the second mode polarized light converted by the mode conversion waveguide; wherein the first direction is a light propagation direction. According to the polarization rotator and the manufacturing method thereof, the device structure can be effectively shortened, and meanwhile efficient conversion rate is achieved.

The invention relates to the technical field of precision optical control, in particular to a sum-difference mode cooperative control double-actuator visual axis stable imaging method and system, and the method comprises the steps: calculating a sum mode variable and a difference mode variable between the angular velocity information of a first actuator and the angular velocity information of a second actuator; performing inverse mode transformation on the two mode variables to obtain independent control commands for respectively controlling the first actuator and the second actuator; the two independent control commands are correspondingly input into the first actuator and the second actuator after being processed through a control algorithm based on data driving. The ultra-high precision of the two actuators is effectively combined, stable control over the optical axis of the optical imaging system is achieved, and the imaging definition and stability of the optical imaging system in the disturbance environment are remarkably improved.

The invention provides a fault position calibration method and system for a flexible DC four-end looped network, and the method comprises the steps: collecting an original voltage traveling wave signal of a fault voltage traveling wave, and carrying out the preprocessing of the original traveling wave signal; performing polarity separation on the preprocessed original traveling wave signal, and performing phase-mode transformation on the original traveling wave signal after polarity separation; carrying out wave head identification on the original traveling wave signal after phase-mode transformation, and judging a path through which each wave head passes; selecting a preset number of wave heads from each wave head, and determining a calculation expression of the preset number of wave heads; and calculating a plurality of different distance measurement results according to the calculation expression of the preset number of wave heads, carrying out weighted average on the plurality of different distance measurement results, and calibrating the initial distance measurement result to obtain the position of the fault point. According to the invention, the position of the fault point can be accurately determined, so that the position of the fault point of the flexible direct-current four-end looped network can be quickly and accurately found out.

The application relates to the technical field of optical communication, and particularly discloses a photon orbital angular momentum mode order multiple transformation device, which comprises an optical coordinate transformation module, an optical 4f low-pass filter module and a reflection module; the optical coordinate transformation module comprises a first phase part and a second phase part with an optical field phase modulation function; a vortex optical field carrying photon orbital angular momentum is emitted from the first phase part, the vortex optical field is transmitted to the reflection module after spiral decomposition and phase modulation of the first phase part, and then is transmitted to the second phase part; the second phase part changes the phase distribution from an angular spiral phase into an angular scaled spiral phase, and then outputs ideal vortex light through the optical 4f low-pass filter module; the photon orbital angular momentum mode order multiple transformation device realizes mode transformation of various multiples, greatly improves the efficiency of mode multiple transformation and the purity after change, and can be widely applied to the field of optical field regulation.

The invention discloses a spiral structure waveguide for vortex light topological charge conversion and an implementation method thereof, and belongs to the field of optical waveguides. The circular waveguide and the spiral structure are combined, the spiral structure is used for regulating and controlling the vortex light mode according to the mode conversion matching condition, and vortex light conversion between any topological charge orders is achieved; according to the invention, complete conversion between different vortex lights is realized, two vortex light mixed beams with different proportions can be generated, and the requirements of generation and utilization of vortex lights with different orders in an integrated photonics on-chip structure are met. According to the method, the problem that topological charges cannot be freely converted among different vortex light modes in a waveguide structure is solved, the application value of the waveguide structure in the aspect of vortex light regulation and control is expanded, and the possibility is provided for an integrated photon platform to utilize vortex light topological charge degree-of-freedom coding information and process calculation tasks. According to the invention, information coding, optical communication, calculation and other applications are carried out by changing the topological charge of the vortex light.

A mode transformation device may include a tapered waveguide having a first face and a second face separated along a guiding direction, where a cross-section of the tapered waveguide at the first face comprises an arrangement of three or more guiding structures, and where the three or more guiding structures include at least a first guiding structure surrounded by a second guiding structure surrounded by third guiding structure. A cross-sectional dimension of at least one of the three or more guiding structures adiabatically changes along the guiding direction such that light propagating through the tapered waveguide has a first optical mode profile at the first face and a second optical mode at the second face, where the light transitions from the first optical mode profile to the second optical mode profile as it propagates along the guiding direction.

The invention refers to a method for coupling of waveguides, providing simultaneous interfacing and polarization and mode conversion between waveguides supporting modes and polarization states with similar or substantially different characteristics, and to a chip (100) comprising a converter structure, and to such converter structure. The invention merges functionalities of mode spot size conversion, mode coupling and transfer, mode type conversion, polarization conversion and polarization splitting. The converter structure is based on vertically stacked waveguides forming a vertical directional coupler (1) connected with different polarization branches (8) integrated into the chip (100).

The present application provides an optical modulator and a control method thereof. The optical modulator includes: an input waveguide for receiving an initial optical signal; a tunable ring resonator, which is coupled to the input waveguide and is used for resonating and modulating the initial optical signal and outputting a first optical signal; a feedback loop waveguide, which is coupled to the tunable ring resonator and is used for receiving and transmitting the first optical signal; a first mode converter, which is coupled to the feedback loop waveguide and is used for performing mode conversion on the first optical signal and outputting a second optical signal; the tunable ring resonator is further used for resonating and modulating the second optical signal and outputting a third optical signal; an output waveguide, which is coupled to the tunable ring resonator and is used for receiving and outputting the third optical signal. The optical signal can be subjected to secondary resonance processing through the tunable ring resonator to improve the extinction ratio of the optical signal.

The invention discloses an active mode demultiplexing module which comprises a mode converter, two optical circulators and a bidirectional semiconductor optical amplifier. The mode converter is used for converting a high-order mode into a fundamental mode to complete primary mode demultiplexing, fundamental mode signals after primary demultiplexing are injected into the bidirectional semiconductor optical amplifier through the two optical circulators from the positive direction and the negative direction respectively, and the signals after being shaped by the bidirectional semiconductor optical amplifier are output by the corresponding optical circulators. A bidirectional symmetrical injection structure is formed, different propagation is beneficial to separation of different signals, and mutual interference, namely mode crosstalk, between forward and reverse signals can be effectively reduced, so that a mode demultiplexing function is better completed, and an output signal has higher signal quality than a primary demultiplexing signal. Besides, by optimizing and adjusting the driving current of the bidirectional semiconductor optical amplifier or an auxiliary optical pumping mode, not only can the gain of the mode channel be dynamically adjusted, but also the power balance of the mode channel and the demultiplexing of a high extinction ratio mode can be realized; the method is especially suitable for receiving few-mode signals in a mode division multiplexing (MDM) optical transmission system and constructing optical switching nodes in a multi-dimensional multiplexing optical network.

The invention discloses an optical polarizer and an optical fiber gyroscope. The optical polarizer comprises a mode hybridization region, a mode coupling region and a light beam combination region, the input end of the mode coupling area is coupled with the output end of the mode hybridization area, and the first output end and the second output end of the mode coupling area are respectively coupled with the first input end and the second input end of the light beam combination area; the mode hybridization region receives input light containing a TE0 mode and a TM0 mode, converts the TM0 mode into a TE1 mode, and then inputs the TE1 mode and the original TE0 mode into the mode coupling region; the mode coupling region outputs the original TE0 mode from the first output end of the mode coupling region, converts the TE1 mode into the TE0 mode, and then outputs the converted TE0 mode from the second output end of the mode coupling region; and the light beam combining area is used for carrying out beam combining processing on the two received beams in a TE0 mode. According to the scheme, the polarization purpose can be achieved, and meanwhile the effect of reducing optical power loss is achieved.

The application provides a method, device and system for light field vector mode conversion, the method comprising: acquiring a cylindrical vector beam field, a fundamental mode Gaussian light array field and a first geometric phase multi-plane light transformation field; determining a first light field and a second light field based on the cylindrical vector beam field, the fundamental mode Gaussian light array field and the first geometric phase multi-plane light transformation field; acquiring a second geometric phase corresponding to a preset condition based on a difference between orthogonal basis vectors of the first geometric phase, the first light field and the second light field and the preset condition; determining a second geometric phase multi-plane light transformation field by using a vector wavefront matching mode based on the second geometric phase; and converting the fundamental mode Gaussian light array field and the cylindrical vector beam field based on the second geometric phase multi-plane light transformation field, thereby realizing multiplexing and demultiplexing of the cylindrical vector beam field, greatly improving the channel capacity of the optical fiber and improving the transmission efficiency of the optical fiber communication.

A device includes a first mode converter and a second mode converter that define a region between the first mode converter and the second mode converter. The region can contain a plurality of optical modes including at least three modes. The first mode converter and the second mode converter can generate a near-field via a conversion between the plurality of optical modes. The first mode converter can receive an input wave of a first mode and the second mode converter can generate an output wave of a second mode different from the first mode. The first mode converter and the second mode converter can generate a confined near-field via a conversion between the plurality of optical modes.

A 2x2 photonic splitter includes two mode converting Y-junctions. A first stage mode converting Y-junction includes input branch ports adapted to receive an input optical signal propagating in a fundamental spatial mode at either of the input branch ports, a first trunk port, and a first mode converting region. The first mode converting region is adapted to convert at least a first power portion of the fundamental spatial mode of the input optical signal when received via at least one of the input branch ports to a higher order spatial mode at the first trunk port. The second stage mode converting Y-junction includes output branch ports adapted to emit output optical signals having the fundamental spatial mode, a second trunk port, and a second mode converting region optically coupling the output branch ports to the second trunk port. A connected trunk section photonically links the trunk ports.

The invention discloses a mode division multiplexing device based on topological optimization and a mode division multiplexing circulating system, and relates to the field of photon integration and optical communication. The manufacturing method of the mode division multiplexing device comprises the following steps: dispersing the whole design area into adjustable material pixels, wherein the design area is silicon on insulator; determining a target function of a mode division multiplexing device by taking maximization of mode conversion efficiency as a target; by taking the objective function as an optimization objective, automatically updating the distribution of material pixels in the whole design area to obtain a quasi-optimal structure; and optimizing the pixels which cannot meet the manufacturing requirements in the optimal structure until the manufacturing requirements can be met. When a mode division multiplexing device is manufactured, an optimal structure can be automatically searched in a continuous or discrete material parameter space, so that a complex geometrical shape which is difficult to intuitively conceal can be excavated, and ultra-compact, low-loss, low-crosstalk, broadband and robust mode division multiplexing multifunctional photonic devices and the like can be realized in an extremely small size.

The application discloses a driving mode control method, a motor driving method and system, and a photographing module. The driving mode control method comprises the following steps: acquiring a first starting time of a signal synchronization process of the photographing module in a photographing process, a second starting time corresponding to an analog-digital conversion process, and a switching time of switching from a first mode to a second mode; acquiring a first difference t1 between the first starting time and the second starting time; acquiring a second difference t2 between the switching time and the second starting time; calculating a delay time according to at least one parameter in a mode conversion period of the analog-digital conversion process, the first difference t1 and the second difference t2, wherein the delay time is used for delaying a mode switching operation, and the analog-digital conversion process is avoided from the second mode; and switching from the second mode to the first mode by taking the delay time as a reference after detecting a synchronization signal. The application can improve the quality of a photographed image.

The application discloses a collaborative protection control method and system for a light storage and charging integrated system. The method comprises the following steps: generating an injection control instruction and sending the injection control instruction to a harmonic feature injection module to perform harmonic injection; continuously collecting impedance monitoring data in an interval time and generating impedance reference data; then, detecting whether the newly collected impedance monitoring data deviates from the impedance reference data according to an island detection rule; if the newly collected impedance monitoring data deviates from the impedance reference data, sending a signal blocking instruction and a shutdown instruction to a bidirectional grid-connected converter; sending a mode conversion instruction to the bidirectional grid-connected converter to switch to a network construction type working mode and monitoring the impedance monitoring data to determine whether a touch risk occurs; if the touch risk occurs, sending a low-power operation instruction to the bidirectional grid-connected converter and issuing a warning information. The above method realizes island detection and touch protection through a harmonic feature injection mode, and improves the reliability of collaborative protection control of the light storage and charging integrated system.

The invention discloses a high-energy pulse column vector fiber laser, which comprises a gain switch pulse seed source, a pre-amplification unit, a mode conversion unit and a main amplification unit which are arranged in sequence, wherein the pre-amplification unit comprises a pre-amplification beam combiner and a pre-amplification double-cladding gain optical fiber which are arranged in sequence, and the pumping end of the pre-amplification beam combiner is connected with a pre-amplification pumping source; the mode conversion unit comprises a mode converter and a polarization controller which are arranged in sequence; the main amplification unit comprises a beam splitter, a plurality of paths of main amplification channels and an optical fiber coupler which are arranged in sequence; wherein each main amplification channel comprises a main amplification beam combiner, a main amplification double-cladding gain optical fiber and a phase delayer which are arranged in sequence, and the pumping end of the main amplification beam combiner is connected with a main amplification pumping source. The pulse column vector fiber laser is combined with a column vector light mode converter and a fiber amplification structure outside a cavity, and high-quality, high-stability and adjustable-repetition-frequency high-power pulse column vector fiber laser output is obtained.

The application provides a display panel and a display device, wherein the time length of the bias adjustment stage and the time length of the non-emitting stage are set to be non-same ratio change, when the display panel is converted from a first mode to a second mode based on the change requirement of brightness, the time length of the non-emitting stage is in a state of being shortened, at this time, the time length of the bias adjustment stage is adjusted in a W1 / L1W2 / L2 mode, so that the change amplitude of the time length of the bias adjustment stage caused by the mode change of the working state is relatively small; that is, the time length of the bias adjustment stage in the second mode is relatively large, and the phenomenon of flicker of the display panel during the mode adjustment in the second mode is avoided. Therefore, the technical scheme provided by the application improves the flicker problem of the display panel under different brightness modes, and ensures that the display device has good display effect.

The invention discloses a dual-terminal distance measurement method and system based on traveling wave attenuation characteristics, and relates to the field of power system fault distance measurement. Voltages and currents of buses at the two ends of a line are measured, and phase-mode transformation and traveling wave decomposition are carried out; establishing a fault traveling wave frequency domain wave equation according to results of phase-mode transformation and traveling wave decomposition, and converting the fault traveling wave frequency domain wave equation into a time domain wave equation; and determining a measured fault traveling wave data window, and substituting traveling wave data in the fault traveling wave data window into the time domain wave equation for solving to obtain a fault distance. Dependence of a traditional method on data synchronization is overcome, and accuracy and practicability of power transmission line fault distance measurement are improved.

The invention relates to the field of silicon-based optoelectronic integration, and particularly discloses an on-chip adaptive wave combination method and feedback system for a polarization diversity MZM, and the system comprises an optical coupling and mode conversion module, a polarization diversity electro-optical modulation module, an optical power collection and photoelectric conversion module, a signal processing and feedback control module, and a tunable wave combination module. After coupling conversion and modulation, two paths of optical power are collected and subjected to photoelectric conversion, a power difference voltage is obtained through an analog circuit, a bias voltage is superposed to generate a control voltage, and an adjustable combiner is driven to dynamically adjust the beam splitting ratio to complete wave combination. The problems that the output power of the polarization diversity MZM fluctuates randomly along with the polarization state, and an existing polarization control scheme is slow in response, complex in architecture and difficult to integrate with a silicon-based process are solved, real-time accurate compensation of power fluctuation is achieved, it is guaranteed that the combined wave output power is stable, the system architecture is simple, power consumption is low, integration with a silicon-based chip monolithic chip is easy, and the application range is wide. And the performance and the compatibility of the integrated photonic link are improved.

This invention relates to a dispersion-compensated ring reflector and its fabrication method. It includes a substrate, a silicon waveguide core layer disposed on the substrate, and a first 1×2 multimode interferometer, a first curved tapered waveguide, a second curved tapered waveguide, a first mode converter, a second mode converter, and a first coupling waveguide disposed on the silicon waveguide core layer. The first 1×2 multimode interferometer has one port at its first end and two ports at its second end. The port at the first end is connected to the incident and exit waveguide cross-sections via a first single-mode waveguide. The two ports at the second end are connected to the inputs of the first and second mode converters via the first and second curved tapered waveguides, respectively. The outputs of the first and second mode converters are connected via the first coupling waveguide. The device provided by this invention is adaptable to various material platforms and has good integration with other devices.

This invention provides a method and system for realizing millimeter-wave ring beams, belonging to the field of millimeter-wave transmission and near-field beamforming technology. It solves the problem in existing technologies that there is no research on the feasibility and implementation method of ring beams to improve the power capacity of the dielectric window. The method includes: S1, constructing a phase correction model for the ring beam realization system; S2, based on the phase correction model, performing a mirror design process for the two sets of reflectors in the ring beam realization system; S3, after completing the mirror design process, obtaining a first set of reflectors and a second set of reflectors; S4, arranging the first set of reflectors and the second set of reflectors in the system, placing the dielectric window between the first set of reflectors and the second set of reflectors, and realizing a millimeter-wave ring beam at the dielectric window by mode transformation of the electromagnetic wave beam through the reflector sets. This invention reduces the peak field strength and maximum temperature rise while maintaining existing hardware costs, significantly increasing the transmission power at the dielectric window.

The invention relates to an optical processing device (DR) for optically processing an incident light beam (I0) which has propagated through a free space and whose phase front is susceptible to distortion. The optical processing device (DR) comprises: mode conversion means (M) configured to break down at least a portion of the incident light beam (I0) into at least two elementary light beams (to); and an integrated photonic device (C) configured to coherently recombine the at least two elementary beams (to) and to produce at least one recombined beam () on the output optical port (P2). The basic light beam (arrival) propagates between the input optical port (P1) and the output optical port (P2) along at least two separate optical paths, respectively. The optical processing device (DR) is characterized in that at least one of the optical paths comprises at least one static delay element (D1, D2, D3) configured to equalize the propagation time of the elementary optical radiation along the optical path.