26 results about "Polarization controller" patented technology

This application provides a semiconductor laser and a terahertz source for generating terahertz waves. The semiconductor laser includes: a substrate; a mesa located on the substrate; and a ridge waveguide and lateral coupling gratings located on the mesa, with the lateral coupling gratings located on both sides of the ridge waveguide. The lateral coupling gratings are configured such that the frequency difference between the fundamental transverse mode wavelength and the second-order transverse mode wavelength of the lasing light emitted by the semiconductor laser is 0.1 THz–10 THz. The semiconductor laser of this application, through the optimized configuration of the ridge waveguide and the lateral coupling gratings on both sides, precisely achieves simultaneous output of the fundamental and second-order transverse modes with a frequency difference on the order of terahertz. Combined with a polarization controller and a nonlinear crystal, it can stably output terahertz waves in the target frequency band. Compared with traditional solutions, the semiconductor laser of this application can simultaneously output the fundamental and second-order transverse modes with a frequency difference on the order of terahertz, offering advantages in miniaturization and low cost.

The application provides a semiconductor laser reservoir pool computing device based on silicon-based micro-resonant cavity optical feedback, and belongs to the technical field of photonic neuromorphic computing. Laser output by a driving laser is modulated by a phase modulator, and then is injected into a response semiconductor laser through a feedback cavity incoupler and a circulator; the output end of the response semiconductor laser is connected to an optical circulator in sequence through a second variable optical attenuator, a polarization controller, a silicon-based micro-resonator and a first variable optical attenuator, so as to form a silicon-based micro-resonator optical feedback loop; the output end of the feedback cavity incoupler is connected to a broadband photodetector, which is used to collect reservoir pool output signals; the phase modulator is loaded with a modulation signal containing an input signal and a random mask, so as to realize input layer signal coding. The application realizes the improvement of overall computing performance.

This invention discloses a simple, multifunctional, integrated 5G analog fronthaul in-band full-duplex communication method for remote units (RUs). This method primarily relates to the fields of optical communication technology and microwave technology. The system structure of the method, as shown in Figure 1 of the specification, includes a laser, downlink vector signal, electrical local oscillator signal, downlink interference signal, target signal, reference signal, 90° electrical coupler, dual-polarization quadrature phase-shift keying modulator, phase modulator, single-mode fiber, optical coupler, polarization beamsplitter, polarization beam combiner, polarization controller, polarizer, and photodetector. The remote unit (RU) uses a single phase (PM) modulator to achieve self-interference cancellation (SIC) combined with anti-fiber dispersion transmission and down-conversion, eliminating the need for bias control and additional local oscillator (LO) branches, resulting in a simple structure. At the central office (CO), the carried downlink signal and local oscillator signal are single-sideband modulated to achieve anti-fiber dispersion transmission. The RU uses wavelength reuse technology to perform PM cascaded down-conversion on the signal received from the uplink, and the SIC is moved from the RU to the CO to simplify the RU. The entire link has no optical filter and is reconfigurable.

The application relates to a method of an electric field sensor based on an optoelectronic oscillator, belonging to the field of optical devices and optical fiber sensing. The device comprises a laser source, a polarization controller, a phase modulator, a fiber Bragg grating with an acrylate glue cavity, a stacked piezoelectric ceramic, an electric field generator, an erbium-doped fiber amplifier, a photodetector, a power divider and an electric amplifier. The stacked piezoelectric ceramic is combined with the fiber Bragg grating with the acrylate glue cavity as a sensing head, the wavelength change of the fiber Bragg grating with the acrylate glue cavity caused by the piezoelectric effect is mapped to the frequency change of the microwave signal generated by the optoelectronic oscillator, and the electric field change value can be obtained by monitoring the microwave signal of the optoelectronic oscillator. In the loop of the optoelectronic oscillator, the electric spectrum analysis technology is used for demodulation, and high-speed and high-resolution electric field measurement can be obtained. The method has the advantages of simple structure, high measurement sensitivity and easy practicability.

This invention discloses a wavelength-tunable dual-cavity ultrafast fiber laser based on rotating optical fibers and its control method, relating to the field of laser technology. The dual-cavity ultrafast fiber laser of this invention integrates a wavelength division multiplexer within a dual-ring resonant cavity, structurally integrating two wavelength channels, each containing an independent gain fiber, to achieve dual-color soliton output and reduce gain competition. By setting an adjustable rotating fiber filter, consisting of a polarization controller, rotating optical fibers, and a polarization-dependent isolator, in the multiplexing section, the center wavelength of both wavelengths is tunable. Simultaneously, the two sub-cavities share the same saturable absorber to achieve passive synchronous mode-locking, and a delay line is introduced into one of the channels to adjust the equivalent cavity length, achieving repetition frequency matching and timing alignment between the two sub-cavities, thereby obtaining stable, tunable, and synchronous dual-wavelength ultrashort pulse output.

The application discloses an interference filter type multi-wavelength erbium-doped fiber laser based on optical path difference regulation, relates to the technical field of a ring-shaped tunable multi-wavelength erbium-doped fiber laser, and comprises a pump source, a wavelength division multiplexer, an erbium-doped fiber, an isolator, a first optical fiber coupler, a three-paddle polarization controller, a polarizer, a Mach-Zehnder interferometer filter containing an adjustable delay line, a black phosphorus saturable absorber and an extrusion type polarization controller which constitute a ring cavity. By connecting a 0-6.6 cm continuous adjustable delay line to one arm, the optical path difference of the filter two arms is accurately regulated, and continuous precise tuning of wavelength spacing of 0.3 nm to 1.54 nm is realized; meanwhile, by combining the nonlinear polarization rotation effect and the hybrid mode-locking mechanism of the few-layer black phosphorus, the mode-locking threshold is significantly reduced, and the long-term stability of the pulse is improved. The laser can realize stable emission of up to six wavelengths at the same time, the wavelength drift is less than 0.75 nm, and the power fluctuation is less than 7.0 dB.

The present application relates to fine particle sensing technology, and particularly relates to a microcavity vibration spectrum system and method for measuring inherent vibration spectrum of fine particles. The microcavity vibration spectrum system comprises an inherent vibration excitation light path unit and a microcavity detection light path unit; the inherent vibration excitation light path unit is sequentially provided with a pulsed light source, a vibrating mirror, an objective lens and a particle to be measured; and the microcavity detection light path unit is sequentially provided with a tunable laser light source, an adjustable attenuator, a polarization controller, a coupling optical waveguide, an optical microcavity, a photodetector and an oscilloscope. The present application can realize precise measurement of sound waves caused by particle vibration of mesoscale particles and biological particles with inherent vibration frequency in the sub-megahertz-gigahertz frequency range.

A diaphragm-type optical fiber micro-vibration measurement apparatus and method based on a single-pass band microwave photonic filter. The apparatus comprises a broadband light source module (1), a three-port circulator (2), an AU diaphragm optical fiber micro-vibration sensor (3), an erbium-doped optical fiber amplifier (4), a polarization controller (5), an electro-optical modulator (6), a power supply module (7), a radio-frequency source module (8), a dispersion compensation optical fiber (9), a photoelectric detector (10), a data acquisition card (11) and a computer (12), wherein the broadband light source module (1) is connected to one port of the three-port circulator (2) by means of an optical fiber connection line.

The application provides a light frequency comb generation device and method based on a series double microcavity structure. The device comprises a pump laser, an optical amplifier, a polarization controller, a first tapered lens fiber, a series double microcavity structure and a second tapered lens fiber connected in sequence. The second tapered lens fiber is connected to a spectrum analyzer and an oscilloscope through a first coupler. The optical amplifier is used to amplify the power of the output laser of the pump laser to reach the power threshold required for microcavity light frequency comb generation. The polarization controller is used to adjust the polarization mode of the output laser of the optical amplifier so that the polarization mode of the laser is the same as the polarization mode of the microcavity light frequency comb to be generated. The series double microcavity structure comprises a bus waveguide and two microcavities coupled thereto and is used to generate a light frequency comb. The application can solve the technical problems of high pump power, low energy conversion efficiency and low parameter selection freedom of the existing light frequency comb based on a single microcavity structure.

This invention discloses a laser polarization rotation state control system, method, apparatus, and storage medium. The system includes: a pump source for providing pump light; a wavelength division multiplexing (WDM) coupler connected to the pump source for coupling the pump light; an erbium-doped gain fiber connected to the WDM coupler for absorbing and amplifying the pump light to obtain signal light; an output coupler connected to the erbium-doped gain fiber for outputting and detecting the signal light; a unidirectional polarization-independent isolator connected to the output coupler for controlling the unidirectional operation of the signal light and maintaining its polarization state; an electrically driven polarization controller connected to the unidirectional polarization-independent isolator for controlling the polarization rotation state of the signal light using a SAC reinforcement learning algorithm; and a saturable absorber carbon nanotube, one end connected to the electrically driven polarization controller and the other end connected to the WDM coupler, for passively mode-locking the signal light for laser output. This invention can improve the detection efficiency of laser polarization rotation state.

This invention discloses a laser linewidth measurement device and method based on switchable channel delay self-heterodyne interferometry, belonging to the field of laser linewidth measurement technology. The laser to be measured is incident on a first fiber coupler via an isolator and splits into two paths: one path enters a computer-controlled first and second optical switches via a three-port fiber circulator, switching between different lengths of delay fiber via the first and second optical switches, rotating the polarization state by 90° via a Faraday rotating mirror before returning along the original path, and then restoring the original polarization state via a polarization controller; the other path undergoes frequency shifting via an acousto-optic frequency shifter. The two paths are combined via a second fiber coupler to generate a beat frequency optical signal, which is then acquired by a photodetector for photoelectric conversion and a spectrum analysis module. The computer fits the beat frequency power spectrum corresponding to different delay lengths to obtain the laser linewidth to be measured. This invention has strong anti-interference capabilities and can simultaneously acquire Lorentz linewidth, Gaussian linewidth, and composite linewidth, with a wide linewidth measurement range.

The application discloses a kind of dual-polarization MIMO demodulation chips and optimization methods for multi-dimensional optical fiber communication.Tunable laser is used to generate incident light beam, MEMS switch controls the incidence of light beam, polarization controller controls the polarization state of incident light, N×N silicon-based optical MIMO chip is used to demultiplex optical mode, photodetector is used to detect the light intensity of each signal, analog-to-digital converter is used to convert the optical signal obtained by detection into electrical signal, single-chip microcomputer is used to analyze the detected signal and optimize the voltage of multi-channel voltage source, multi-channel voltage source controls the dual-polarization thermo-optic phase shifter on N×N optical MIMO chip, so as to realize the demodulation of signal.At the same time, the application also discloses an optimization method of dual-polarization thermo-optic phase shifter and a simulation method of dual-polarization 3dB adiabatic coupler.The chip has the characteristics of dual-polarization, large bandwidth, high robustness, low loss, high integration and simple manufacturing.

This invention discloses a method for detecting copper ion concentration based on a hydrogel-coated PMPCF-MZI sensor and a fluorescence colorimetric dual-sensor. The detection device consists of a broadband light source, a single-mode optical fiber, a polarization controller, a flow cell, a PMPCF-MZI sensor, and a spectrometer. In the fiber optic detection path, light emitted from the broadband light source passes through the polarization controller and is input to the hydrogel-coated PMPCF-MZI, transforming into interference peaks of specific wavelengths. These peaks are displayed on the spectrometer. The hydrogel's volume and refractive index change after adsorbing copper ions, manifesting as a shift in the interference spectrum on the spectrometer. By comparing the relationship between different copper ion concentrations and the interference spectrum shift, rapid, accurate, and trace detection of copper ions in the aquatic environment is achieved. In the fluorescence detection path, the fluorescent detection solution is mixed with the test solution and irradiated with an ultraviolet lamp, inducing a change in fluorescence intensity, achieving visual qualitative detection. This invention employs a dual-system collaborative design, combining advantages such as simple structure, low detection limit, fast response time, easy operation, and high visualization. It has significant practical value and promising application prospects for rapid copper ion detection in the future.

This invention relates to a Brillouin optical time-domain analyzer chip and system, comprising: a light source selection and distribution unit, a probe light generation unit, a pump light generation unit, a light detection unit, an optical signal port, and an electrical signal port; external light source and laser signals are input through the optical signal port and respectively input to the probe light generation unit and the pump light generation unit through the light source selection and distribution unit; the probe light generation unit includes an IQ modulator and a filter based on a dual parallel Mach-Zehnder modulator structure; the pump light generation unit includes two cascaded intensity modulators based on a Mach-Zehnder modulator structure and a polarization controller; the light detection unit includes a photodetector for receiving the probe light input. Compared with the prior art, this invention integrates the core optoelectronic devices of the Brillouin optical time-domain analyzer sensing system onto a silicon photonics chip, effectively achieving temperature sensing while maintaining high performance, meeting application requirements.

The specification discloses a polarization control laser power quantum stabilization device, method and laser emitting equipment to improve the stability of laser power. The device comprises a laser power adjusting unit configured to adjust the laser polarization state of linearly polarized light output by a laser by using a polarization controller, and output the to-be-stabilized power laser after polarization maintaining transmission; and a feedback control unit configured to take the to-be-stabilized power laser as a monitoring object, introduce it into an atomic clock, change the output frequency of the atomic clock, and adjust the laser polarization state in the laser power adjusting unit based on the deviation between the output frequency and a given output frequency by using a feedback control method to stabilize the power of the output laser. The device has strong environmental interference resistance, reduces the influence of laser polarization change in the traditional method on power stability, improves the sensitivity and response capability of the system to small changes in stable power, and more accurately controls the stable laser power.

The application discloses an optical fiber gyroscope, a disturbance control method and equipment, relates to the technical field of circuit detection, and the optical fiber gyroscope comprises a wide-spectrum light source, a polarization controller, a polarization maintaining coupler, a polarization beam splitter, a second detector, a third detector and a gyro drive demodulation circuit; the polarization maintaining coupler is connected with the polarization beam splitter in an optical path, and the gyro drive demodulation circuit is electrically connected with the polarization controller; the polarization beam splitter is used for receiving first light waves emitted by the wide-spectrum light source and split by the polarization maintaining coupler, splitting the first light waves again, and sending second light waves split again to the gyro drive demodulation circuit; the gyro drive demodulation circuit is used for generating an adjusting signal based on the second light waves and sending the adjusting signal to the polarization controller; and the polarization controller is used for adjusting the polarization state of incident light based on the adjusting signal. The measurement precision and stability of the gyroscope can be improved.

An ultra-narrow laser spectral width measurement and calibration instrument relates to the fields of laser communication and optoelectronic technology. The ultra-narrow laser spectral width measurement and calibration instrument includes: an ultra-narrow laser source under test (1), a 3dB optical coupler (12), an erbium-doped fiber amplifier (2), a polarization controller (3), a polarization beam splitter (4), first to fourth optical circulators (31), (32), (33), and (34), a first fiber grating reflector (51), a second fiber grating reflector (52), a first polarization-maintaining fiber (61), a second polarization-maintaining fiber (62), a first optical isolator (71), a second optical isolator (72), a 1:9 optical coupler (6), a first adjustable Faraday polarization mirror (81), a second adjustable Faraday polarization mirror (82), a 3×3 optical coupler (7), a spectrum analyzer (9), and a digital signal processor (10).

This invention relates to the field of measurement technology, and particularly to an out-of-plane displacement measurement device and method based on Sagnac interferometry, comprising a laser transmission mechanism, a Sagnac ring, and a fiber optic balanced detection mechanism. The laser transmission mechanism includes a low-coherence light source, a fiber polarizer, a first polarization controller, and a circulator. The Sagnac ring includes a first polarization-maintaining beam splitter, a long polarization-maintaining fiber arm, a short polarization-maintaining fiber arm, and a second polarization-maintaining beam splitter. The fiber optic balanced detection mechanism includes a second polarization controller, a third polarization-maintaining beam splitter, and a balanced photodetector. By setting the long and short polarization-maintaining fiber arms in the Sagnac ring and combining them with a fiber-coupled probe to achieve a 90° rotation of the reflected light polarization state, a non-reciprocal interference optical path is cleverly constructed. This not only retains the inherent advantage of the Sagnac ring interferometer's strong resistance to environmental interference but also successfully achieves high-sensitivity measurement of out-of-plane displacement.

This invention provides a quantitative detection method for exosomes based on aptamer-functionalized tilted fiber optic gratings combined with gold nanoparticle signal amplification. The detection device consists of a broadband light source, a single-mode fiber, an electrically driven polarization controller, fiber optic clamp 1, a TFBG aptamer sensor, a reaction chamber, an optical three-dimensional adjustment frame, another fiber optic clamp 2, and a spectrometer. The detection principle can be summarized as follows: light emitted from the broadband light source is transmitted through the single-mode fiber to the electrically driven polarization controller, where the incident light is modulated into a P-polarization state. The P-state light is transmitted to the TFBG aptamer sensor, which is tightly suspended and fixed in the reaction chamber by the fiber optic clamp. The final output light signal is presented as a transmission spectrum on the spectrometer. During the detection process, the MUC1 aptamer layer on the surface of the TFBG aptamer sensor selectively captures exosomes produced by breast cancer cell lines. Furthermore, by combining with CD63 aptamers to aggregate gold nanoparticles, the refractive index change on the surface of the TFBG aptamer sensor is amplified, further amplifying the drift in the transmission spectrum. By comparing the relationship between different exosome solution concentrations and the amount of transmission spectrum drift, rapid and highly sensitive quantitative detection of exosomes is achieved. This invention provides a new method for the quantitative detection of exosomes that is highly sensitive, simple to operate, and rapid, and has broad application value in early diagnosis and prognosis in clinical medicine.

This invention relates to the field of optical communication technology, specifically proposing a high-precision two-stage endless polarization controller and control method, including a polarization beam splitting and rotation module, an endless phase shifter, a first 3dB coupler, a balanced photodiode, and a control circuit. The endless phase shifter is used to adjust the relative phase difference between the first and second optical signals according to the multi-path drive signals to obtain a third and a fourth optical signal. The first 3dB coupler is used to perform power distribution on the third and fourth optical signals to obtain a first optical power signal and a second optical power signal. The control circuit is used to perform algorithmic processing on the first and second electrical signals to generate multi-path drive signals, and sends the multi-path drive signals to the endless phase shifter. By applying the endless phase shifter to a two-stage polarization control architecture, seamless, dead-zone-free control in the entire polarization space is achieved, reducing transient bit errors caused by voltage reset, and providing a reliable hardware foundation for high-precision polarization management and coherent optical communication.

The application relates to an automatic polarization controller-based optical transmission system for short-distance high-capacity optical interconnection, comprising an optical transceiver module, an automatic polarization controller and a MIMO-free structure DSP module. The optical transceiver module divides the outgoing light field of a transmitting end laser into two parts, one part of which is modulated to obtain signal light, and the other part is used as pilot light. After passing through the automatic polarization controller, the pilot light is fed to the receiving end of the optical transceiver module together with the signal light for coherent detection, and the receiving signal is recovered through the MIMO-free structure DSP module. Meanwhile, a simple training sequence is adopted to solve the mismatch between the signal light link and the pilot light link. The application solves the problem that high-speed coherent optical communication technology is restricted by cost, bandwidth, power consumption and integration, and cannot be used in short-distance optical interconnection scenes.

The present application relates to the technical field of laser, and especially relates to a wide-tuning ultra-narrow linewidth laser, which comprises a boost type optical amplifier, a first optical isolator, an optical coupler, a first polarization controller, a Fabry-Perot filter optical fiber type ring cavity laser, a second optical isolator, an echo wall mode microcavity, a second polarization controller and a third optical isolator which are connected in sequence; wherein the output end of the third optical isolator is further connected with the input end of the boost type optical amplifier, the output end of the boost type optical amplifier is connected with the input end of the first optical isolator, the output end of the first optical isolator is connected with the input end of the optical coupler, the optical coupler has two output ends, one output end of the optical coupler is used as the output end of the wide-tuning ultra-narrow linewidth laser to output target laser, and the other output end of the optical coupler is connected with the first polarization controller. The present application is at least beneficial to make the wide-tuning ultra-narrow linewidth laser realize the characteristics of ultra-wide wavelength range tuning and ultra-narrow linewidth simultaneously.

Provided is a wavelength selective switch where crosstalk is improved and miniaturization is realized. The wavelength selective switch includes: one or more input ports; one or more output ports; a polarization controller that adjusts a polarization state of light incident from the input ports; a dispersive element that demultiplexes wavelength-multiplexed light incident from the input ports; and a deflection element that controls deflection of the demultiplexed light. The dispersive element is a liquid crystal diffraction element having a liquid crystal alignment pattern where an orientation of an optical axis derived from a liquid crystal compound changes while continuously rotating in at least one in-plane direction.

The application discloses a miniaturized time phase decoder and a QKD receiver, wherein all on-chip devices are made based on a PLC process, the difference between the lengths of interferometer arms can be accurately controlled by means of an existing process, and a phase shifter or a phase modulator or the like device does not need to be arranged in an interference ring to perform interference dimension stabilization; all functional devices are passive devices except for an external single-photon detector, and the time phase decoder has high stability and reliability; and since the mode of the PLC planar optical waveguide is basically consistent with the mode in the optical fiber, the polarization state does not need to be specially controlled before being coupled into the chip, the requirement for external polarization controllers and the like devices is reduced, and the volume of the QKD receiver is further reduced.

The application discloses a near-transform limit nanosecond pulse mode-locked fiber laser with periodic bifurcation and a producing method. The laser is a fiber ring cavity which comprises a wavelength division multiplexer, an erbium-doped fiber, a first polarization controller, a polarization detector, a dispersion control unit, an output coupler, a fiber isolator and a second polarization controller which are connected in sequence in a closed loop. The method comprises the following steps: coupling pump continuous light into the laser through the wavelength division multiplexer; absorbing the pump continuous light by the erbium-doped fiber and radiating gain pulses in a long-wave band; oscillating the generated pulses in the fiber laser cavity; through the cooperation of the first polarization controller, the polarization detector and the second polarization controller, generating equivalent saturated absorption effect by using the nonlinear polarization rotation generated when the gain pulses propagate in the fiber, and realizing pulse mode-locking; and making the fiber laser work in an abnormal dispersion region so that the generated pulses satisfy the soliton area theorem and near-transform limit pulses are generated. The application can realize nanosecond pulse periodic bifurcation output of a short-cavity fiber laser.

The application discloses a kind of based on single-double mode optical fiber laser's ultra-short pulse generation method and device, method includes: pump light enters erbium-doped optical fiber by double-mode wavelength division multiplexer, excitation erbium ion to upper level and form particle number inversion, produce stimulated emission, amplify laser signal;Pass through double-mode optical fiber coupler, a small amount of laser output to outside cavity and measure, remaining laser continues to oscillate in cavity;Remaining laser passes through polarization controller and adjusts the polarization state in resonant cavity, to ensure that laser is stably transmitted in cavity, utilize carbon nanotube saturable absorber to realize the mode locking of laser, ensure that stable ultra-short pulse is generated;Laser passes through double-mode isolator and ensures that optical pulse is unidirectional operation in resonant cavity, re-enters double-mode wavelength division multiplexer and forms circulation;After periodic mode coupling, finally form stable mode-locked pulse.The application is suitable for few-mode fiber mode-locked laser, with simple structure, easy to construct and maintain, with very high stability and reliability.