63 results about "Tunable laser" patented technology

This invention provides a wind erosion monitoring system and method based on distributed optical fiber, belonging to the field of optical-based wind and sand monitoring technology. It includes: constructing a wind erosion monitoring system comprising a linearly tunable laser, an optical isolator, a first coupler, an upper branch, a lower branch, a sand particle capture sensor, a photoelectric detection and acquisition module, and a host computer; utilizing the Rayleigh scattering signal of the linearly swept laser in the sensing optical fiber and the interference with a reference light, the vibration information distributed along the optical fiber is obtained by demodulating the beat frequency signal; combining the constructed sand particle impact and optical fiber coupling model, the dynamic strain generated by sand particle impact is converted into phase changes, realizing the acquisition of sand particle impact location, sand particle size, and sand particle quantity. This invention enables continuous distributed monitoring of wind and sand flows with high spatial resolution, and has advantages such as resistance to electromagnetic interference, strong environmental adaptability, and multi-parameter sensing, and can operate stably for a long time in harsh desert environments.

This invention discloses a laser cleaning device and method for surfaces made of multiple materials, belonging to the field of industrial manufacturing technology. Addressing the problems of poor adaptability, imprecise endpoint determination, narrow material compatibility, and high process development costs in existing laser cleaning methods, the device comprises a central control module, a multi-wavelength tunable laser, a laser-induced breakdown spectroscopy device, an AI spectral model, a process digital twin system, and a multi-physics field coupling simulation module, forming a closed-loop control system. The cleaning method achieves cleaning by constructing a digital twin model, using LIBS-AI coupling to identify material states, simulating and optimizing parameters, monitoring cleaning across multiple modes, intelligently determining the endpoint, and iteratively optimizing the process. In this invention, the device effectively improves adaptability and cleaning accuracy through real-time component identification, dynamic wavelength adjustment, multi-source signal fusion criteria, and simulation prediction. It can adapt to a wide range of spectral materials, shorten the process cycle, and is suitable for high-precision laser cleaning of multiple materials and complex surfaces.

The application discloses a frequency modulation rate variable laser linear frequency modulation device and a frequency modulation method thereof. The device comprises a wideband tunable laser, a micro-optical lens, a beam splitter, an adjustable optical delay unbalanced MZ interferometer, a balanced photodetector, a phase discriminator, a loop filter, an up / down switch control circuit and an integrator. The adjustable optical delay unbalanced MZ interferometer comprises two couplers and an adjustable optical fiber delay line unit. According to the relationship between the linear frequency modulation light frequency and time of the upper and lower arms of the interferometer, when the delay amount of the adjustable optical fiber delay line unit changes, the frequency modulation rate of the output laser can be changed. The application changes the time delay of the light by using the adjustable optical fiber delay line, so that the frequency modulation rate can be changed.

The application discloses a microwave photon filter and a control method thereof, and belongs to the field of optical fiber communication. The filter comprises an optical ring cavity, a tunable laser source, an electro-optic intensity modulator, a photoelectric detector and an electric vector network analyzer. The first input end of the electro-optic intensity modulator is connected with the output end of the tunable laser source, the second input port of the electro-optic intensity modulator is connected with the output end of the electric vector network analyzer, and the output end of the electro-optic intensity modulator is connected with the input end of an optical circulator in the optical ring cavity. The output end of the optical circulator in the optical ring cavity is connected with the input end of the photoelectric detector, and the output end of the photoelectric detector is connected with the input end of the electric vector network analyzer. The application can overcome the problem that the device parameters cannot be adjusted after the structure of the microwave photon filter is determined.

This invention relates to the fields of optical fiber communication and microwave photonics. Existing tunable dual-passband microwave photonic filters suffer from poor passband stability and cannot meet practical application requirements. This invention provides a narrow-band tunable dual-passband microwave photonic filter using a Brillouin fiber laser. It generates dual-tone pump light to excite the Brillouin using a tunable laser source and an intensity modulator. Combined with a Brillouin fiber oscillator and a cascaded Fabry-Perot cavity, the Brillouin gain spectrum is narrowed to the kHz level. Simultaneously, the different periodic resonant frequencies of the two ring cavities effectively suppress side modes, filtering out the desired frequency band signal. Furthermore, by synchronously tuning the center frequencies of the two passbands of the filter by changing the pump light wavelength, and simultaneously controlling the output frequency of the signal generator, the frequency interval between the two passbands is changed, ultimately realizing a narrow-linewidth tunable dual-passband microwave photonic filter.

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.

The present application relates to the technical field of industrial park environmental governance, and discloses a park waste gas collaborative monitoring and carbon flow regulation system and method based on edge computing, which comprises a sampling pretreatment module, a sensor integration module, an edge computing unit, a dynamic regulation module and a wireless communication module, and the sensor integration module comprises a shared optical chamber, a tunable laser emitter and a detector array. Through the integrated sensing design of the shared optical chamber combined with time division multiplexing laser detection, the present application realizes the synchronous and accurate collection of multiple pollutants and carbon flow concentrations, and breaks the monitoring data island. At the same time, through the local closed-loop processing of the edge computing unit and the collaborative index threshold trigger mechanism, the present application eliminates environmental interference and avoids the problem of pollution reduction and carbon increase, and greatly improves the response speed and regulation coordination.

The application relates to the technical field of optical fiber sensing and pressure monitoring, and discloses a fiber grating high-speed sensing system for pressure detection. The system comprises a light source module, a sensor module and a detection, collection and demodulation module. The light source module is based on an MG-Y tunable laser and outputs high-speed linear scanning light; the sensor module is composed of a pressure conduction device, a pressure testing device, a temperature compensation device, a sealed shell and a fixing structure, and converts the measured pressure and environmental temperature change into optical signals with different wavelength drift characteristics; the detection, collection and demodulation module adopts high-speed photoelectric detection and a double-FPGA processing unit to synchronously collect and real-timely demodulate the reflected spectrum. The application is collaboratively designed through a pressure conversion structure and an MG-Y high-speed sweep frequency demodulation platform, high-precision, high-stability and high-speed real-time detection of pressure signals are realized, different ranges can be expanded by changing the thickness of the pressure diaphragm, and long-term creep drift is reduced through an oxygen-free glue welding fixing mode.

The application relates to a 9-shaped cavity laser with independently and continuously tunable wavelength and pulse width, which comprises a 9-shaped cavity oscillator and a laser parameter tuning and state monitoring feedback system. The 9-shaped cavity oscillator can realize self-starting fundamental mode locking through the introduction of a non-reciprocal device and the optimization of the positions of the devices in the 9-shaped cavity oscillator and the lengths of the optical fibers. The laser parameter tuning and state monitoring feedback system can continuously tune the wavelength and pulse width of the 9-shaped cavity oscillator, and can monitor the output state of the oscillator in real time to determine whether the oscillator is in a stable mode-locked state and control the angle of a half-wave plate and the current value of a laser diode by using a random collision recovery algorithm so that the 9-shaped cavity oscillator can always keep in a stable mode-locked state. The application can realize the independent and continuous tuning of the wavelength and pulse width of the 9-shaped cavity laser in a stable mode-locked state, and has a wide application prospect in the field of tunable lasers.

This invention proposes a high-precision method for measuring airflow thrust by extracting the Doppler frequency shift difference from the scanning absorption spectrum. A tunable laser performs forward and reverse scanning of the absorption spectrum. The laser wavenumber scanning waveform is symmetrical about the lowest wavenumber point. The laser beam is split into two beams, which cross the longitudinal section of the airflow center. The target gas absorption spectrum curve is obtained by measuring the laser intensity curve. The sum of the central wavenumbers of the absorption spectrum in both forward and reverse scans along the airflow path is calculated, as is the sum of the central wavenumbers in both forward and reverse scans against the airflow path. The Doppler frequency shift difference is extracted from the difference between the two sums of central wavenumbers, thus measuring the airflow velocity. The static temperature of the airflow is obtained using colorimetric thermometry, and the static pressure of the airflow is obtained using a nonlinear fitting method. The thrust is calculated by combining the airflow velocity, static temperature, and static pressure. This invention achieves airflow velocity measurement resistant to temporal noise interference and has significant application prospects in the field of integrated space-ground thrust measurement for engines.

The application discloses a driving circuit of a tunable laser and the tunable laser, and belongs to the technical field of laser driving circuits.The driving circuit of the tunable laser comprises a signal control module, a voltage follower module, a switch signal conversion module, a signal superposition module and a voltage-controlled current source module; the signal control module is connected with the input ends of the voltage follower module and the switch signal conversion module; the signal superposition module is connected with the output ends of the voltage follower module and the switch signal conversion module; the output end of the signal superposition module is connected with the input end of the voltage-controlled current source module, and the output end of the voltage-controlled current source module acts on the tunable laser; and the output signal of the voltage follower module and the output signal of the switch signal conversion module are converted into the working current of the tunable laser through the signal superposition module and the voltage-controlled current source module, so that the tunable and stable working current is provided for the multi-wavelength array laser, and the quick and stable switching of the wavelength of the tunable laser is realized.

This invention discloses a high-efficiency nonlinear optical frequency converter based on high-power continuous optical transmission using quartz micro / nano fiber, comprising a wavelength-tunable laser, an optical fiber amplifier, a quartz micro / nano fiber, a sealed cavity, and an optical fiber low-pass filter; the quartz micro / nano fiber includes a first untapered portion, a second untapered portion, a first tapered transition region, a second tapered transition region, and a waist region, transmitting an optical field TE. 01 The mode cutoff method precisely controls the waist diameter of micro / nano fiber and accurately tunes the input light wavelength. The nonlinear light frequency conversion process excited by high-power continuous light transmitted in quartz micro / nano fiber satisfies perfect phase matching. The fundamental mode of the input light and the higher-order mode fields of the harmonic signal light have high overlap in the waveguide mode, which can efficiently generate continuous second and third harmonic signal light. The device has high stability, high efficiency, and low cost, and can be applied in fiber lasers, all-optical signal processing, fiber optic sensing and other fields.

The application discloses a kind of dual-frequency modulation transfer spectroscopy laser frequency stabilization device and method, construct the dual-frequency modulation signal including first frequency component and second frequency component, according to dual-frequency modulation signal driving fiber electro-optic phase modulator to laser is carried out dual-frequency electro-optic phase modulation;Photoelectric detector carries out detection to the polarized beam splitter output light and obtains saturated absorption signal, to saturated absorption signal in turn carries out quadrature demodulation and low-pass filter processing and obtains first error signal and second error signal, first error signal and second error signal are superimposed to obtain dual-frequency error signal;Further, tunable laser is carried out closed-loop feedback control, realizes laser frequency stabilization.The application obtains two different frequency components error signal using dual-frequency modulation transfer spectroscopy detection technology, improves slope and intensity by adding operation, improves frequency discrimination sensitivity and anti-interference ability, is conducive to peak search determination and realizes the precision locking of laser frequency to rubidium absorption peak, with good practicability.

An opto-electronic system including a PIC that includes a semiconductor-based tunable laser source that can achieve single-mode lasing thereby emitting optical radiation having a predefined linewidth at a predefined operating wavelength. The PIC also includes an optical measurement unit that can receive the optical radiation emitted by said laser source, and provide a signal representative for the received optical radiation to a control unit of the opto-electronic system that is operatively connected with said laser source and the optical measurement unit. The opto-electronic system enables omitting external optical measurement equipment thereby enabling a faster and cheaper way of locking of the predefined operating wavelength of said laser and achieving the predefined linewidth. A method of improved tuning of a semiconductor-based tunable laser source of an opto-electronic system.

This invention discloses an optically pumped tunable vertical-cavity surface-emitting laser (VCSEL), a mirror, and their applications. The wavelength-selective mirror includes a phase-matching region and an optimization region arranged sequentially along the vertical direction. The phase-matching region is formed by periodically alternating stacks of x pairs of first high-refractive-index material layers and first low-refractive-index material layers along the vertical direction. The optimization region is formed by y pairs of second high-refractive-index material layers and z pairs of second low-refractive-index material layers, which are alternately stacked along the vertical direction, and the optical thicknesses of the second high-refractive-index material layers and the second low-refractive-index material layers are unequal. This invention breaks away from the traditional single optimization paradigm centered on lasing light in DBRs, significantly improving optical pumping efficiency while ensuring a wide tuning range and free spectral range, thereby realizing a highly efficient wide-tunable single-longitudinal-mode output MEMS-VCSEL, laying the foundation for next-generation high-performance tunable lasers.

The application discloses an ultra-narrow linewidth Littman tunable laser, comprising a semiconductor laser diode, a collimating lens, a blazed grating and a tunable mirror which is arranged opposite to the grating plane of the blazed grating and is angle-adjustable, wherein the semiconductor laser diode, the collimating lens and the blazed grating are located on the same optical axis, and the grating plane of the blazed grating is distributed in intersection with the optical axis; and the application further comprises a cavity length-adjustable F-P etalon, which is located on the output light path of the zero-order diffraction light of the blazed grating, and the zero-order diffraction light is output as laser after passing through the F-P etalon. In this way, the semiconductor laser diode, the collimating lens, the blazed grating and the tunable mirror form a standard Littman tunable laser, and the cavity length-adjustable F-P etalon is additionally arranged, so that the cavity distance of the F-P etalon is adjusted to match the narrow-band filtering characteristics of the F-P etalon with the output wavelength of the semiconductor laser diode.

1. Name of the product in this design: Output linewidth compressor. 2. Application of this design: This design is mainly used for the compression of the output spectral linewidth of tunable lasers, as well as for research and development and production in fields such as high-speed optical communication and silicon-based optoelectronic chip testing. 3. The key design feature of this product is its shape. 4. The image or photograph that best illustrates the design's key points: a 3D model.

The application provides a tunable laser multi-point absolute frequency locking device and method, and belongs to the technical field of lasers. The device comprises: a tunable laser unit provided with a frequency tuning port for receiving an external control signal; an interference measurement unit comprising a first beam splitter and an interference system; a frequency reference unit comprising a phase modulator, a gas absorption chamber and a photodetector arranged in sequence on the same optical axis; a locking and scanning control unit for identifying absorption peak characteristics according to an electrical signal, dynamically outputting a compensation signal to the frequency tuning port to realize frequency locking and control the interference system to perform interference measurement, or outputting a scanning signal to the frequency tuning port to control the tunable laser unit to perform frequency scanning. The application can obtain an interference signal with high contrast and high signal-to-noise ratio during measurement, is conducive to continuously and quickly locking multiple absolute frequency points on a wide spectrum, and greatly improves the efficiency, accuracy and application range of sweep frequency interference measurement.

An oscillation wavelength adjustment type TLD for adjusting a control amount of a resonator length L, independently from physical property values of a waveguide material when a waveguide is used in the phase adjustment, without an external resonator structure in accordance with a MEMS technology employs a reflective phase adjuster including a multi-mode interference waveguide, which is optically coupled to an optical gain waveguide and has a configuration including one input port and five output ports, and a reflective delay line array connected to an output waveguide on a side of the five output ports of the multi-mode interference waveguide. Five reflective delay lines provided in the reflective delay line array are capable of adjusting the intensity of reciprocating light in accordance with a wavelength change of transmitted light.

This application proposes a Littman external cavity tunable laser, relating to the field of laser technology, comprising: a semiconductor optoelectronic device for outputting a broadband optical signal; a focusing module for collimating and focusing the broadband optical signal, projecting the focused light onto a mode-spot conversion polarization rotating beam splitter; a mode-spot conversion polarization rotating beam splitter for adapting the mode size and controlling the polarization state of the focused light, filtering out non-target polarization components, outputting a target polarized optical signal with a single polarization state, and also for adapting the mode size of the reflected external cavity feedback light; and a tuning output module for spatial dispersion separation of different wavelength components, generating zero-order diffracted light as the laser output light, and generating first-order diffracted light as the external cavity feedback light, and achieving laser wavelength tuning by changing the wavelength of the external cavity feedback light. This application can solve the defect of unstable polarization state during the tuning process of traditional Littman lasers.

The present application provides an integrated device, comprising: a substrate; a modulation region, a front grating region, a laser gain region, and a back grating region arranged in sequence on the same surface of the substrate; the modulation region comprises at least two sub-modulator regions, wherein the band gap wavelength of the modulation region is shorter than that of the laser gain region, and the band gap wavelengths of the at least two sub-modulator regions are different; the front grating region, the laser gain region, and the back grating region constitute a wide tunable laser for emitting laser with a wide tunable wavelength; the at least two sub-modulator regions are used for switching according to the lasing wavelength of the laser or sharing the at least two sub-modulator regions to modulate the intensity of the laser. Another aspect of the present application provides a preparation method of the above integrated device.

The present application relates to the field of optical fiber sensing technology, and more particularly to a kind of FP-FBG fusion spectrum demodulation method based on discrete spectrum analysis, comprising: driving tunable laser quasi-continuous scanning FP-FBG sensor and obtaining discrete reflection spectrum sequence through photoelectric acquisition circuit, determining the index of FBG peak in the sequence and obtaining FBG center wavelength by using centroid method fitting, selecting target neighborhood with the index as center and replacing the neighborhood sequence value with the intensity mean of spectrum sequence to obtain processed FP spectrum sequence, performing autocorrelation transformation on the processed FP spectrum sequence to obtain autocorrelation sequence, and finding the peak-to-peak distance between main peak and adjacent peak in the autocorrelation sequence, and finally calculating the sensing demodulation result according to the calibration relationship.The present application can effectively remove the shielding of narrow-band FBG to FP spectrum period information, suppress random noise and significantly improve the demodulation accuracy of low-quality spectrum.

A tunable laser comprising at least two gain chips configured to generate light and a wavelength selection circuit. The wavelength selection circuit comprising a first waveguide coupled to a first gain chip of the at least two gain chips, a second waveguide coupled to a second gain chip of the at least two gain chips, a first wavelength selective photonic ring resonator optically coupled to the first waveguide, a second wavelength selective photonic ring resonator optically coupled to second waveguide, a third waveguide optically coupled to the first wavelength selective photonic ring resonator and the second wavelength selective photonic ring resonator; and a control circuit. The control circuit is configured to apply a first current to the first gain chip to bias the first gain chip, tune the first wavelength selective photonic ring resonator to a target wavelength, and tune the second wavelength selective ring resonator off-resonance.

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 relates to the field of radio frequency signal measurement technology, and proposes a microwave photonic system and method for nanosecond-level measurement of frequency and angle of arrival. The system includes: an optical frequency comb generation module, in which a narrow-linewidth laser generated by a tunable laser is amplified by an erbium-doped fiber amplifier and then excited by the Kerr nonlinear effect to generate a coherent optical frequency comb; an antenna receiving module, which receives a first radio frequency signal and a second radio frequency signal; an electro-optic modulation module, in which the first radio frequency signal and the second radio frequency signal are respectively input to a first sub-modulator and a second sub-modulator, and a third sub-modulator is used to combine the first and second modulated lights and introduce a preset phase difference to obtain a target optical pulse signal; and a frequency-time mapping and detection module, in which the target optical pulse signal is frequency-time mapped via a dispersive fiber, a photodetector converts the mapped optical signal into an electrical pulse train, and an oscilloscope is used to observe the time interval between adjacent peaks and the pulse amplitude information of the electrical pulse train to obtain the characteristic parameters of the radio frequency signal.

This invention discloses a closed-loop precise control method and system for laser-induced acoustic pressure wave (APW) in complex intravascular lesions. This method belongs to the field of laser medical technology. This application employs a physical model for APW generation coupled with a laser-plasma-liquid medium, and designs an APW simulation calculation and tunable laser control system based on this model. By adjusting parameters such as the wavelength, pulse width, and peak power density of the tunable laser, precise forward control of the generated APW intensity is achieved. Simultaneously, based on the target APW intensity required clinically, the optimal laser parameter combination can be iteratively calculated in reverse, forming a closed-loop design from "treatment target" to "laser parameters." This invention combines a laser physical model with clinical needs, realizing the quantification, predictability, and controllability of APW intensity, providing a precise and intelligent technical solution for the treatment of intravascular calcification. It can significantly simplify physician operations and improve the safety and effectiveness of treatment.

This invention discloses a method for polarization detection based on the superposition of orthogonal vortex beams, comprising the following steps: An incident beam generated by a tunable laser passes sequentially through a linear polarizer and a quarter-wave plate (QWP). The transmission axis α of the linear polarizer and the fast axis β of the QWP are rotated to achieve an arbitrary polarization state in the transmitted beam. An optical lens is used to focus the incident light with the arbitrary polarization state. The beam reflected from the metasurface is then processed by an objective lens to magnify the beam. The focused incident beam illuminates the optical metasurface, and the composite beam generated from the metasurface is collected by a CCD camera after passing through an analyzer. This invention overcomes the problems of large size and poor integration inherent in traditional polarization measurement systems. Metasurfaces offer potential for vertical integration and design flexibility, and provide a new direction for combining polarization information with other related technologies. It also meets the requirements of device miniaturization and system integration.

This invention provides a multi-stage fiber-coupled semiconductor laser, belonging to the field of fiber-coupled semiconductor technology. It includes: a fiber coupling module for outputting a wavelength-locked and tunable laser beam; a multi-stage spectral synthesis unit for performing step-by-step spectral synthesis on the laser beam to output a multi-path spectrally synthesized beam; and a fiber combining unit for combining the multi-path spectrally synthesized beam and outputting the synthesized laser beam from a single output fiber. This invention solves the technical problem in existing semiconductor lasers where it is difficult to balance beam quality and brightness when increasing power, achieving a balance between high power and high brightness, improving system synthesis efficiency and scalability, and enhancing output beam quality and availability.