1380 results about "Optical modulator" patented technology

The invention relates to the technical field of optical fiber frequency transmission, in particular to a distributed optical fiber optical frequency transmission method and system.The distributed optical fiber optical frequency transmission system is composed of a sending end and a plurality of receiving ends which are connected through an optical fiber link. An optical signal transmission module of a sending end divides laser generated by a laser into reference light and modulated light, the modulated light is transmitted to a receiving end after being subjected to positive frequency shift and wavelength division multiplexing, and return light is received at the same time. The signal processing module performs beat frequency processing on the reference light and the return light to obtain a radio frequency signal, performs phase processing to obtain an instantaneous frequency value, and modulates and converts the instantaneous frequency value into an optical signal through the optical transmitter. And the optical modulator module at the receiving end demodulates the modulated optical signal to obtain an instantaneous frequency value, and drives the modulator at the receiving end by using the frequency value to obtain a final optical frequency signal. According to the system, distributed high-precision optical frequency transmission is realized.

The invention provides a high-power multimode fiber laser amplifier based on wavefront shaping. The high-power multimode fiber laser amplifier comprises a seed light wavefront control unit, a multimode gain fiber amplification unit and an output light spot detection and feedback unit, the seed light wavefront control unit is used for carrying out wavefront modulation on the seed light output by the polarization seed laser by using a spatial light modulator loaded with a phase diagram; the multimode gain optical fiber amplification unit is used for performing power amplification on the seed light which is output by the seed light wavefront control system and is subjected to output wavefront modulation; and the output light spot detection and feedback unit is used for outputting the laser of most power of the multimode gain fiber amplification system, collecting the rest laser of a small part of power for far-field light spot information detection, calculating the corresponding far-field barrel medium power based on the detected far-field light spot information, and outputting the far-field barrel medium power. And the power in the far-field barrel is used as an evaluation function to operate an optimization algorithm to generate an optimal phase diagram, and the optimal phase diagram is loaded on the spatial light modulator to realize closed-loop feedback control.

The invention discloses a signal-to-noise ratio improvement method based on a multi-core optical fiber dual-channel distributed acoustic sensing system, and the method comprises the steps: carrying out the light splitting of light emitted by a narrow linewidth laser through a first coupler C1, enabling one path of light to generate a pulse signal through an acoustic optical modulator (AOM), enabling the other path of light to pass through a second coupler C2, and enabling the other path of light to pass through a second coupler C1; the pulse light is divided into two beams of transmission light, the two beams of transmission light are injected into a connected sensing optical fiber through two groups of erbium-doped optical fiber amplifiers (EDFA), two groups of filters, two groups of circulators and a fan-in coupler Fan-in Coupler, and the pulse light is subjected to backward Rayleigh scattering in the sensing optical fiber; based on a dual-channel DAS system, a multi-core optical fiber is used as a sensing optical fiber, three cores and four cores of the multi-core optical fiber are connected in series to form two sensing channels, seven-core space division signals are multiplexed, the equivalent self-noise pressure suppression effect of the seven-core space division signals is analyzed, after noise correlation is removed through a time domain dislocation-frequency domain phase shift method, the signal-to-noise ratio gain can be increased to 8.65 dB, and the signal-to-noise ratio gain can be increased to 8.65 dB. And the detection capability of the system on low-frequency weak signals can be improved.

The invention discloses an equivalent self-noise pressure suppression method and device based on a multi-core optical fiber space division multiplexing signal, light emitted by a narrow linewidth laser is split through a first coupler C1, one path of light passes through an acousto-optic modulator AOM to generate a pulse signal, and then the pulse signal passes through a second coupler C2 to generate a pulse signal; the pulse light is divided into two beams of transmission light, the two beams of transmission light are injected into a connected sensing optical fiber through two groups of erbium-doped optical fiber amplifiers (EDFA), two groups of filters, two groups of circulators and a fan-in coupler Fan-in Coupler, and the pulse light is subjected to backward Rayleigh scattering in the sensing optical fiber; based on the dual-channel DAS system, the multi-core optical fiber serves as the sensing optical fiber, three cores and four cores of the multi-core optical fiber are connected in series to form two sensing channels, seven-core space division signals are multiplexed, the equivalent self-noise suppression effect of the seven-core space division signals is analyzed, and the detection capacity of the system for low-frequency weak signals can be improved.

The invention discloses a rapid polarized light acoustic imaging device which comprises an excitation source, a light beam shaping module, a rapid polarization modulation module, an energy feedback module, a rapid scanning module and an acquisition processing module. And receiving photoacoustic signals corresponding to the exciting light in four different polarization states for calculation, and extracting anisotropy information of the sample. Compared with multiple times of scanning a sample or modulating the polarization state by rotating a half-wave plate, the problems of dislocation of multiple times of polarization acquisition points and false positive calculation are avoided, meanwhile, the time interval generated by continuously modulating the laser pulses is short, and energy fluctuation among the four pulses and errors caused by fluctuation are reduced. According to the invention, the limitation of the precision and speed of polarized light acoustic microscopic imaging is overcome, the microstructure characteristics in the target sample can be rapidly, accurately and highly sensitively detected, and the method has great application prospects in biomedical imaging and high-precision material detection.

The invention discloses a jitter calibration system and method for a superconducting nanowire single-photon detector. Comprising an FPGA platform used for generating periodic pulse calibration signals, a radio frequency pulse amplifier, a lithium niobate electrooptical modulator and a bias voltage controller thereof, a 1550nm 3kHz linewidth distributed feedback laser, a program control optical attenuator, a three-paddle polarization controller, an SNSPD single photon detector, a multichannel TDC module and an upper computer used for processing data. The calibration method is simple and low in cost, can calibrate a correction curve of the relation between SNSPD detection photon additional jitter and detection recovery time caused by pulse accumulation, compensates additional jitter, and can effectively solve the problem of jitter deterioration generated by SNSPD under a high counting rate in high-speed detection application.

The invention discloses an MZ silicon optical modulator phase bias point adjusting method, electronic equipment, a medium and a program product thereof, and belongs to the technical field of optical communication. The minimum value and the maximum value of the sampling voltage of a photoelectric detector in any period and the current value range of a Heater corresponding to a monotone increasing interval or a monotone decreasing interval are searched; and then a set phase offset point is indexed in the current value range of the Heater. According to the invention, ADC sampling I / O port resources of a pair of differential photoelectric detectors and a micro control unit (MCU) of an MZ silicon optical chip are utilized, and the detection voltage of a photoelectric detector (MPD) of the MZ modulator is periodically changed in a sine rule along with the current change of a thermo-optic phase shifter (Heater); and the phase offset point locking value only needs to select one working point of any period as the modulation locking point of the optical module.

An optical modulator includes an electro-optic layer including an electro-optic material, and a material layer arranged below the electro-optic layer and having a dielectric constant lower than a dielectric constant of the electro-optic layer. The optical modulator includes a core layer arranged below the material layer and having a refractive index higher than refractive indices of the electro-optic layer and the material layer, and an electrode that applies an electric signal to the electro-optic layer. The refractive index of the material layer is 0.85 times the refractive index of the electro-optic layer or higher.

An optical device includes: a first optical system; and a second optical system. The first optical system includes a first light splitting device configured to split measurement light emitted from a first light source into a first measurement light and a second measurement light and then mix the split measurement light, a first mirror configured to add a first modulation signal by being moved in an entering direction of the first measurement light and reflecting the first measurement light, a second mirror configured to reflect the second measurement light, and a first light receiving device configured to receive the measurement light including a sample-derived signal and the first modulation signal and output a first light receiving signal. The second optical system includes a second light source configured to emit laser light, an optical modulator configured to add a second modulation signal to the laser light, and a second light receiving device configured to receive the laser light including a displacement signal generated by reflection on the first mirror and the second modulation signal and output a second light receiving signal.

The invention relates to a packaging structure and packaging method for an optical module and an optical chip, and the packaging structure comprises a receiving end assembly, a stepped metal heat sink, and a silicon-based optical interconnection assembly which is pasted on the stepped metal heat sink. The silicon-based optical interconnection assembly comprises a laser, a silicon light beam splitter, a lens group, a light transmission compensation gasket, a silicon light modulator and an optical fiber array; coplanar coupling is formed between the laser and the silicon light beam splitter. The silicon light beam splitter and at least part of the collimating lens in the lens group are fixed on the light transmission compensation gasket; the optical fiber array and the silicon light modulator realize waveguide matching in an active coupling mode; the silicon light modulator and the receiving end assembly are separately arranged at least at a preset interval, and the optical fiber array and / or the receiving end assembly are / is covered with a metal isolation cover. According to the invention, the problems of high cost of multiple light sources, easy pollution of an open light path and yield bottleneck caused by low-reliability glue in the prior art are solved, and finally, a packaging scheme which is compact in structure, stable in process and high in mass production is formed.

Disclosed herein is an optical frequency comb generator for a distributed acoustic anomaly detection system. The system can include a continuous wave frequency modulated laser source configured to generate a laser signal. The system can include an acousto-optical modulator configured to modulate the laser signal by altering an amplitude and / or frequency of the laser signal based on an RF drive signal applied to the AOM, and to output an optical pulse with multiple frequency sidebands based on the modulation. The output can form an optical frequency comb usable detecting and locating acoustic anomalies within a structure under observation.

A system for optically modulating a plurality of optical channels includes a power delivery module adapted to convert a coherent light beam into a plurality of optical channels, at least one optical modulator, optically coupled to the power delivery module, the at least one optical modulator adapted to optically modulate each of the plurality of the optical channels, and a vacuum chamber having a trapping plane therein, the vacuum chamber adapted to generate an addressable array of trapped particles at the trapping plane, wherein each of the plurality of optical channels is optically coupled to at least one of the trapped particles of the addressable array.

The invention relates to the technical field of measurement and detection, and discloses an endoscopic imaging and temperature sensing integrated system, which comprises an optical imaging and temperature measuring device, a signal detection device and a control terminal, and is characterized in that the optical imaging and temperature measuring device comprises an excitation light path module, a grating fiber module and a sample control module; the signal detection device comprises a fluorescence detection module and a spectral measurement module, and the control terminal is used for calculating a hologram according to the light field information, sending the hologram to the light modulator to enable the light modulator to carry out wavefront shaping on the first laser based on the hologram, generating a fluorescence imaging graph according to a fluorescence signal, and sending the fluorescence imaging graph to the spectral measurement module. And determining the temperature of the to-be-measured sample according to the spectral information. By utilizing the wavefront shaping technology, the influence of the Bragg grating engraved in the multimode fiber on the light spot output by the multimode fiber can be reduced, the endoscopic imaging quality is improved, and high-quality images can be obtained while the temperature is measured based on the single multimode fiber.

The invention discloses a novel phi-OTDR (optical time domain reflectometry) system with low sampling rate requirement and polarization suppression, which belongs to the field of distributed optical fiber sensing and consists of a laser, three optical splitters, two acoustic optical modulators, three 3dB couplers, three balance detectors, a polarization controller, two polarization beam splitters, a data acquisition card and a computer. On the basis of a traditional phi-OTDR, a double-path AOM structure is introduced, and one path of optical signal is led out as a reference signal to participate in signal demodulation after light splitting and coupling, so that the requirement of a system on a DAQ sampling rate is reduced. And meanwhile, a polarization fading suppression structure is added in the system to adjust the optical signal, so that the output of two paths of cross-polarization signals is realized, and the influence of polarization fading is suppressed in combination with a phase optimal selection algorithm based on a time domain window. While the requirement of a traditional phi-OTDR system for the DAQ sampling rate is effectively reduced, the influence of polarization fading on phase extraction is suppressed, and the precision of system disturbance monitoring is improved.

Methods, systems, and apparatus, including computer programs encoded on computer storage media, for generating, transmitting, directing, receiving, and processing optical subcarriers. In some implementations, a system includes a Tier 1 switch that supplies a plurality of data channels; a transmitter that receives the plurality of data channels, the transmitter including an optical modulator that supplies a plurality of optical subcarriers based on the plurality of data channels; an optical platform that receives the plurality of optical subcarriers, the optical platform having a plurality of outputs, each of which supplying at least one of the plurality of subcarriers; a plurality of receivers, each receiving one or more of the plurality of optical subcarriers and supplying one or more of the plurality of data channels; and a plurality of servers, each of which receiving one or more of the plurality of data channels.

The invention relates to a construction method of a photon neural network, an image processing method, equipment and a medium, and the construction method comprises the steps: forming a silicon waveguide on a silicon-based substrate, periodically arranging phase change units on the surface of the silicon waveguide to form a two-dimensional array, and constructing a phase change metasurface with a beam splitting function by regulating and controlling the state of the phase change units. An input port and an output port are connected through a tapered waveguide to form an optical power beam splitter; output optical signals pass through a crossed waveguide and a directional coupler and are arranged according to a convolution kernel matrix structure, and a photon convolution kernel is constructed. A multi-wavelength laser source, an optical modulator and a photoelectric detector are integrated, the state of a phase change unit is dynamically regulated and controlled, and a photon neural network is established. And after matrix operation, the optical signal is converted into an electric signal by the photoelectric detector and is output to the processing module, so that the network performance is remarkably improved, and an efficient and low-energy-consumption scheme is provided for deep learning.

An optical computation system includes a light source configured to produce a pump beam, an optical modulator configured to modulate the pump beam based on the modulation mask to generate a modulated beam, a non-linear medium configured to convert a portion of the modulated beam to a second harmonic (SH) beam and to produce an output including the SH beam and an unconverted portion of the pump beam, and a dichroic mirror configured to receive the output of the non-linear medium and to decouple the SH beam and the unconverted portion of the pump beam, a detector configured to detect a first optical power of the unconverted portion of the pump beam and to detect a second optical power of the SH beam, and a controller configured to generate an updated modulation mask based on the first and second optical powers for transmission to the optical modulator.

According to the optical fiber interference sensor and the application method thereof, an electro-optical frequency comb is introduced to screen out two comb lines to form a photon-assisted millimeter wave light source, interference is carried out in two frequency spectral regions subsequently, common phase fluctuation is counteracted based on inherent phase coherence, and the strict requirement for the line width index of a laser is avoided. Meanwhile, the two acoustic optical modulators connected in parallel are introduced into the reference arm and the interference arm for frequency shift, the problem of co-frequency crosstalk caused by residual zero-order diffraction of the acoustic optical modulators is solved, and the sensing precision is substantially improved.

An optical modulator with which electrical connection between a signal electrode and signal wiring of a wiring substrate can be reliably made even in a case where a width of the signal electrode in an action portion of an optical control substrate is narrow is provided. An optical modulator includes an optical control substrate (1) that includes an optical waveguide (OW) including at least a branched waveguide which branches one light wave into two light waves, and that includes a control electrode for applying an electrical field to the branched waveguide, and a wiring substrate provided with a wiring which relays an electrical signal to be applied to the control electrode or with a wiring which terminates the electrical signal, in which the control electrode is provided with a signal electrode(S), the wiring is provided with signal wiring, and in a part (Sc) in which electrical connection is made between the signal electrode(S) and the signal wiring, a clearance (W1) in which the branched waveguide (OW) sandwiches the signal electrode is wider than a clearance (W2) in which the branched waveguide sandwiches the signal electrode in an action portion in which the control electrode applies the electrical field to the branched waveguide.

An optical modulator includes, a semiconductor substrate, an optical waveguide portion disposed on the semiconductor substrate, a first P-N junction disposed on the semiconductor substrate, and a second P-N disposed on the semiconductor substrate. The optical waveguide portion provides an optical path for light that is to be modulated. The first P-N junction is disposed on the semiconductor substrate along the optical path and defines a border between an N-doped portion disposed on the semiconductor substrate and a P-doped portion disposed on the semiconductor substrate. The second P-N junction is disposed on a portion of the semiconductor substrate alongside the optical path and spaced apart from the first P-N junction.

A delay control circuit includes a delay circuit configured to provide a predetermined delay to signals input to a plurality of electrode segments provided in series along one or both of two waveguides forming a Mach-Zehnder interferometer of an optical modulator, a control circuit configured to select two electrode segments from the plurality of electrode segments, and control a delay amount between the two electrode segments that are selected, a frequency filter configured to extract a predetermined frequency component from output light of the Mach-Zehnder interferometer, in a state where identical signals that vary at random are input to the two electrode segments, and a monitor configured to monitor a power of the extracted predetermined frequency component. The control circuit controls the delay amount between the two electrode segments based on a monitored result of the extracted predetermined frequency component.

Disclosed are a heterogeneously integrated optical modulator and a manufacturing method thereof. The modulator includes a substrate having a trench, an input waveguide disposed at one side of the trench, an output waveguide disposed at the other side of the trench, a first Mach-Zehnder interferometer including first branch waveguides disposed between the input waveguide and the output waveguide and a heater disposed on one of the first branch waveguides, and second Mach-Zehnder interferometers connected to each of the first branch waveguides.

The invention discloses an equivalent self-noise pressure suppression method based on a dual-channel distributed acoustic sensing system, and the method comprises the steps: carrying out the light splitting of light emitted by a narrow-linewidth laser through a first coupler C1, enabling one path of light to generate a pulse signal through an acoustic optical modulator (AOM), enabling the other path of light to pass through a second coupler C2, and enabling the other path of light to pass through a second coupler C1; the pulse light is divided into two beams of transmission light, the two beams of transmission light are injected into a connected sensing optical fiber through two groups of erbium-doped optical fiber amplifiers (EDFA), two groups of filters, two groups of circulators and a fan-in coupler Fan-in Coupler, and the pulse light is subjected to backward Rayleigh scattering in the sensing optical fiber; according to the invention, based on a dual-channel DAS system, two fiber cores of the multi-core optical fiber are used as sensing optical fibers, and the space division signals of the two cores are multiplexed, so that the performance that the equivalent self-noise pressure drop is 2.54 dB in the frequency band of 100-1000Hz is realized under the condition that the noise correlation coefficient of the dual-core signals is 0.11, and the detection capability of the system on low-frequency weak signals can be improved.

An optical modulator including a driving module, waveguide(s), and differential electrodes is described. The driving module has a first number of differential inputs and a second number of differential outputs. The second number is equal to the first number multiplied by an even integer. The waveguide(s) include a thin film lithium-containing (TFLC) electro-optic material. Each of the waveguide(s) has multiple arms. The differential electrodes are coupled to the second number of differential outputs, each of the plurality of differential electrodes including a positive electrode and a negative electrode, at least a portion of an arm of the plurality of arms between a portion of the positive electrode and a portion of the negative electrode.

Provided are a laser interferometer capable of reducing the frequency of a signal calculated and processed in a demodulation circuit and reducing the cost of the demodulation circuit, and a spectroscopic device provided with the laser interferometer. A laser interferometer is provided with: an optical modulator that adds a modulation signal to laser light using a resonator element; a light receiving element that detects a change in the intensity of the laser light including the sampled signal and the modulated signal, and outputs a laser reception signal; a signal oscillation unit that generates a reference signal of a first frequency with the vibration element as a source vibration; and a demodulation circuit that demodulates the sampled signal from the laser reception signal on the basis of the reference signal, the demodulation circuit comprising: a DC offset removal unit that removes the offset; a first phase regulator that regulates the phase of the reference signal; a first multiplier that multiplies the laser reception signal by a reference signal; a first filter; a second multiplier multiplying the first multiplication signal by a reference signal; a second filter; and a phase calculator that calculates a phase.

The invention provides a dual-mode gravitational acceleration precision measurement system and method based on a light floating effect. According to the system, a 1064nm laser double-beam correlation structure is adopted, a strong focusing light trap is formed in a gravity orthogonal direction, and micron-sized silicon dioxide particles are stably captured. In the absolute measurement mode, the acousto-optic modulator is used for controlling the on-off of the laser, the high-speed position detection module is used for detecting and recording the free falling motion trail of the particles and the displacement amplitude showing the resonance state after re-capturing, and the absolute gravitational acceleration parameter is inverted. In a relative measurement mode, weak focusing 532nm laser is configured along the gravity direction to construct a gravity compensation light trap, and after absolute gravitational acceleration reference measurement is completed, the laser is modulated by an acoustic optical modulator to accurately balance the gravity of particles, so that the particles enter a quasi-balance state. When the external gravitational field changes slightly, the characteristic displacement of the particles in the gravity direction is extracted, and the change of the relative gravitational acceleration can be monitored continuously.

This spatial optical communication transceiver comprises: a light source (1101) that generates laser light; an optical modulator (1102) that superimposes a communication signal on the laser light generated by the light source (1101); an OHPA (1103) that amplifies the laser light after superimposition by the optical modulator (1102); a collimator (1105) that includes a fiber connector (11051) and a collimator lens (11052), converts the laser light after amplification by the OHPA (1103) into spatial light, and emits transmission light, which is the spatial light; an optical telescope (1108) that expands the beam width of the transmission light emitted by the collimator (1105) and emits the same onto a spatial transmission path; a drive mechanism (1112) capable of adjusting the focal length of the collimator lens (11052); and a drive controller (1113) that determines a drive amount of the drive mechanism (1112) such that the product of a free space loss calculated from the distance between the host device and a communication partner spatial optical communication transceiver (11) and a transmission gain determined by a beam divergence angle of the transmission light is constant.

Methods, devices, and systems for driving optical modulators. In one aspect, a driver includes a first circuit having a first switch coupled between a first input and a first output and a second circuit having a second switch coupled between a second input and a second output. Each of the first and second switches is configured to receive a control signal adjustable to control a corresponding signal path with a corresponding input electronic signal. The first and second circuits are configured to control a rising edge and a falling edge of an output electronic signal at an output of the driver that is based on a first output electronic signal at the first output and a second output electronic signal at the second output. The output of the driver is electrically coupled to the optical modulator to provide the output electronic signal to modulate an optical signal.

The invention relates to the field of performance testing of high-precision fiber-optic gyroscopes, and discloses an automatic testing method and system for the extinction ratio of a high-precision fiber-optic gyroscope, and the method comprises the following steps: constructing a signal light path and a reference light path, and combining the output light of the signal light path and the reference light path into a combined light signal in an orthogonal polarization state; integrally measuring the extinction ratio of the combined optical signal by using an extinction ratio tester to obtain a measured value; the control unit compares the measured value with a target value of 0dB and generates a control instruction based on a difference value; the voltage controller automatically adjusts the voltage of the integrated optical modulator in the signal light path according to the instruction, and iterative optimization is carried out through closed-loop feedback until the actually measured extinction ratio reaches a target value; and finally recording and solidifying the optimal voltage value. According to the invention, single and accurate extinction ratio overall measurement is used for replacing two times of error-prone independent optical power measurement, full-automatic closed-loop control is realized, the precision, efficiency and consistency of optical power balance are remarkably improved, and the skill requirements on operators are reduced.

The invention discloses a TGD-OFDR / OCC-BOTDR integrated multi-parameter sensing system and a working method thereof, and relates to the technical field of optical fiber sensors. The multi-parameter sensing system comprises a laser, an optical fiber coupler, an electro-optical modulator, an optical fiber circulator, an optical fiber Bragg grating, an acoustic optical modulator, an erbium-doped optical fiber amplifier, a random scrambler, a piezoelectric ceramic tube, a heating vessel, a delay optical fiber, a photoelectric balance detector, a filter and detector, a data acquisition card, a polarization controller, a direct-current power supply and a microwave source. An arbitrary waveform generator and the like. According to the invention, multiple parameters can be represented at the same time, the measuring speed is fast, and the sampling rate of the system can be effectively improved under the condition that sensing parameters are the same; the method has the advantage of high spatial resolution; the sensor has the advantages of high fusion and low cost, can realize simultaneous measurement of vibration and temperature / strain through single sensing, and is high in fusion and effective in cost control.