63 results about "Laser linewidth" patented technology

The invention discloses an external cavity tunable laser linewidth compression system for realizing wavelength phase locking based on mutual injection of gain chips. The external cavity tunable laser linewidth compression system comprises a red light semiconductor laser main gain chip, a first collimation optical system, a blazed grating, a tuning rotating mirror, a reflector, a power supply driving system and a double-path feedback amplification system, the double-path feedback amplification system comprises a first secondary gain chip, a second secondary gain chip, a second collimation optical system, a third collimation optical system and a polarization-free beam splitter prism; and the red light semiconductor laser main gain chip, the first secondary gain chip and the second secondary gain chip are all connected with the power supply driving system. Therefore, the technical problems of low output infrared light power, poor stability and narrow mode-hopping-free tuning range in the prior art are solved, and high-power, narrow-linewidth, high-stability and large-range mode-hopping-free continuous tuning red light output can be realized.

The invention relates to the technical field of optoelectronic devices, in particular to a laser based on two different gratings and a metal grating with a phase interval of lambda / 2, which comprises a gain chip, a gain chip optical waveguide, an optical waveguide substrate, an optical waveguide, an annular resonant optical waveguide and a metal BRAGG reflecting grating. A unique outer cavity structure is adopted, a traditional interlayer semiconductor grating is abandoned, a top metal grating is adopted, a traditional DFB sandwich type secondary epitaxy manufacturing process is greatly simplified and avoided, the production cost is reduced, particularly, the metal grating is divided into two parts with similar but different grating constants, and the phase positions of the two gratings are pulled by lambda / 2, so that the performance of the DFB is improved. According to the design, the side mode rejection ratio (SMSR) of laser beams can be effectively improved, the laser line width is compressed, a guarantee is provided for stable work of the laser in a high-performance application scene, and the grating reflection efficiency is effectively improved by combining a'mouth-to-mouth 'coupling butt joint mode of the gain chip and the optical waveguide substrate.

The invention provides a start key type soliton micro-comb multi-line multiplexing system and a control method, and the system comprises a first soliton micro-comb generation and control module, a second soliton micro-comb generation and control module, a distance measurement module, a gas spectrum analysis module, a communication module and a processing module. The first soliton micro-comb generation and control module and the second soliton micro-comb generation and control module respectively generate a first soliton optical frequency comb and a second soliton optical frequency comb; the distance measurement module, the gas spectral analysis module and the communication module respectively output distance measurement data, gas spectral analysis data, a modulation signal and a local oscillation signal based on the first soliton optical frequency comb and the second soliton optical frequency comb; and the processing module receives the distance measurement data, the gas spectral analysis data, the modulation signal and the local oscillation signal and outputs a distance measurement result, a gas spectral analysis result and a modulation result. The system is simple in structure and operation, narrow in laser line width and excellent in performance, has no special requirements on the environment, and has reliability and robustness.

A surface inspection system can be provided with a laser spot size or a laser line width that is selectable based on a measurable aspect of the objects under test that project upward or downward from a surface under test. The larger laser spot size or line width can be selected to cover a larger area of the surface under test at a time, which can increase scanning speed over the surface under test and enhance system measurement throughput.

The invention relates to the technical field of sensing, and discloses a demodulator chip with a phase noise compensation function and an optical fiber sound wave sensing system, and the demodulator chip comprises an optical port module, a first polarization filter, a beam splitter module, a modulator, a coherent receiving module and a phase noise extraction module. The optical port module is used for acquiring an incident laser signal, outputting probe light, acquiring scattered light and coupling with the delay optical fiber; the first polarization filter is connected with the optical port module; the beam splitter module is connected with the first polarization filter; the beam splitter module is connected with the optical port module through the modulator; the coherent receiving module is connected with the beam splitter module; the coherent receiving module is connected with the optical port module; the beam splitter module is connected with the phase noise extraction module, and the phase noise extraction module is connected to the delay optical fiber; the phase noise extraction module is used for extracting phase noise through a delay self-coherence mode; the requirement for the laser line width can be lowered, and the sensing performance under the same laser line width level is improved.

This invention provides a self-heterodyne detection system capable of stably and over long periods of time measuring broadband laser linewidths. [Solution] The present invention discloses a self-heterodyne detection system. The system may include a frequency comb light source that generates light, a photodetector that detects the light, an electrical spectrum analyzer connected to the photodetector that analyzes the frequency and wavelength of the light using the detection signal of the photodetector, an interferometer including an input coupler provided between the frequency comb light source and the photodetector to receive the light, a branch waveguide branched by the input coupler, and an output coupler connected to the branch waveguide, and a programmable filter provided in the branch waveguide to select the peak wavelength of the light.

The invention discloses a printing method for modulating the line width through double lasers, and belongs to the technical field of 3D printing. The method comprises the following steps that two sets of long-strip-shaped laser beams are set, and the scanning widths of the two sets of long-strip-shaped laser beams are both D; the to-be-printed pattern is divided into a plurality of printing blocks, and the width of the printing blocks is not larger than D; and when each printing block is printed, the sum of the power of the two sets of long-strip-shaped laser beams is modulated to be equal to the power needed by metal melting, the two sets of long-strip-shaped laser beams conduct synchronous scanning in the length direction of the printing blocks, and in the scanning process, according to the actual line width d of the current printing position, the laser overlapping area of the two sets of long-strip-shaped laser beams is adjusted, the width of the overlapping area is the same as the actual line width d at the current position, and the position of the overlapping area is overlapped with the position of the current to-be-printed part. According to the invention, thickness modulation can be carried out at microsecond-level time in the printing process, and when the same line is scanned, the size of the line width can be changed at will according to a printing pattern, so that the printing efficiency is improved.

Disclosed is an optical feedback cavity ring-down spectroscopy system without phase control. The system comprises: a light source module, used for generating a laser of a predetermined wavelength; an optical feedback module, used for feeding back a part of the laser generated by the light source module into the light source module, and generating strong feedback or moderate feedback, so as to narrow the line width of the laser; an optical cavity module, used for increasing the effective action distance between the laser and a target detection substance, and exciting an optical cavity ring-down signal by means of achieving resonance between the laser and an optical cavity; a trigger light-cutting module, used to instantaneously cut off incident light of the optical cavity module to facilitate detection; a detection module, used to detect a transmitted optical signal outputted by the optical cavity module, convert the transmitted optical signal into a voltage signal, to be used as an optical cavity ring-down signal; and a data acquisition module, used to acquire the optical cavity ring-down signal outputted by the detection module, and perform exponential fitting on the optical cavity ring-down signal to obtain a ring-down time.

The invention provides a narrow-linewidth high-power output external cavity semiconductor laser, and relates to the technical field of laser. The narrow-linewidth high-power output external cavity semiconductor laser comprises a packaging shell, a gain chip, a collimating lens assembly, an etalon assembly, a volume Bragg grating and a laser output assembly, a cavity is formed in the packaging shell, and the gain chip, the collimating lens assembly, the etalon assembly and the volume Bragg grating are all arranged in the cavity. A volume Bragg grating is adopted as a mode selection feedback element, and a single longitudinal mode can be selected in combination with a gain curve; the etalon assembly is arranged on the laser light path between the collimating lens assembly and the volume Bragg grating, the etalon assembly can improve the Q value of the laser resonant cavity and compress the laser line width, the laser line width can reach the kHz magnitude, the output power can reach tens of mW, and the whole laser has the advantages of being compact in structure, high in stability and high in environmental adaptability.

The application relates to a kind of multi-channel short delay optical fiber laser linewidth measurement methods, the laser to be measured is divided into multiple channels by coupler after passing through optical isolator, wherein the first group of optical signals are frequency-shifted by acousto-optic modulator, the remaining optical signals are coupled with the first group of frequency-shifted optical signals after passing through different lengths of short delay optical fiber, converted into optical signals after input to photodetector, finally output to oscilloscope or spectrum analyzer to extract the power difference of power spectrum first-order envelope peak and second-order envelope peak, and finally the linewidth parameter of the laser to be measured is obtained by correlation processing. The application can effectively reduce the length of delay optical fiber, reduce the sensitivity of the system to environmental vibration interference by 100 times, and the multi-channel information collection of different lengths of delay optical fiber can obtain the average level of the laser linewidth output in a time period and under a working state at one time, which is beneficial to eliminate the accidental error influence in linewidth measurement.

The utility model discloses a laser line width measuring device based on a short optical fiber, relates to the technical field of delayed self-heterodyne measurement, and aims to solve the problem that a laser line width measuring result is inaccurate due to the existence of 1 / f frequency noise in the conventional delayed self-heterodyne technology. In the device, laser to be measured is divided into two laser beams through the first coupler, one laser beam enters the acousto-optic modulator, the other laser beam enters the gear-adjustable short optical fiber delay line device, and the laser emitted from the acousto-optic modulator and the laser emitted from the gear-adjustable short optical fiber delay line device are combined through the second coupler and then are transmitted to the second coupler. And the high-speed photoelectric detector is used for detecting, and detection data is sent to the electric spectrum analyzer. The shift-adjustable short optical fiber delay line device has a plurality of shifts, different shifts correspond to delay optical fibers with different lengths, 1 / f frequency noise can be effectively avoided, the laser line width measurement precision is improved, the laser line width measurement range is expanded, and the shift-adjustable short optical fiber delay line device is suitable for measurement of lasers with various line widths.

The invention relates to the technical field of optoelectronic devices, in particular to a laser based on two different gratings and a metal grating with a phase interval of lambda / 2, which comprises a gain chip, a gain chip optical waveguide, a grating optical waveguide substrate, an optical waveguide and a metal BRAGG reflecting grating. A unique outer cavity structure is adopted, a traditional interlayer semiconductor grating is abandoned, a top metal grating is adopted, a traditional DFB sandwich type secondary epitaxy manufacturing process is greatly simplified and avoided, the production cost is reduced, particularly, the metal grating is divided into two parts with similar but different grating constants, and the phase positions of the two gratings are pulled by lambda / 2, so that the performance of the DFB is improved. According to the design, the side mode rejection ratio (SMSR) of laser beams can be effectively improved, the laser line width is compressed, a guarantee is provided for stable work of the laser in a high-performance application scene, and the grating reflection efficiency is effectively improved by combining a'mouth-to-mouth 'coupling butt joint mode of the gain chip and the grating optical waveguide substrate.

The utility model provides a frequency-doubled laser linewidth narrowing device. The device comprises a pumping module and a laser resonant cavity, the pumping module is used for providing linearly polarized light in a specific polarization direction to a light path; the laser resonant cavity is internally provided with a gain medium, at least one birefringence optical filter and a frequency doubling crystal which are sequentially arranged along an optical path, and the at least one birefringence optical filter is inserted into the optical path at a Brewster angle; wherein the linearly polarized light is focused in the gain medium, the central wavelength of the linearly polarized light is the same as the absorption peak wavelength of the gain medium, and the polarization direction of the linearly polarized light is the same as the maximum absorption direction of the gain medium. According to the invention, the birefringence optical filter (group) inserted into the laser resonant cavity can be specifically adjusted, so that narrow-band filtering can be conveniently and quickly realized in various intracavity frequency doubling lasers, and compared with the prior art, the introduced power loss is relatively small.

The application discloses a narrow-linewidth laser external cavity coupling system and method based on linewidth test feedback, adopts a self-feedback mechanism to perform external cavity coupling, wherein through optical power real-time feedback, the laser can be ensured to be in the best working state when measuring the linewidth, so that the accuracy of the linewidth measurement can be improved, and reliable data can be provided for subsequent external cavity position adjustment; after the linewidth measurement is completed, the external cavity clamp displacement table can be controlled to adjust the position of the external cavity of the narrow-linewidth laser according to the linewidth, until the linewidth of the laser output by the external cavity reaches a preset target, and the best coupling position of the external cavity can be determined; thus, the application comprehensively considers the optical power and the laser linewidth to perform external cavity coupling, can ensure that the actual performance meets the design index, ensures the parameter consistency, and the whole process is fully automated, without the intervention of personnel, effectively avoiding the subjective influence of the operator, so that the process stability and the production efficiency are improved.

The invention relates to the technical field of laser, and provides a wide-tuning narrow-linewidth mid-infrared light parameter laser generation device, which comprises a pump laser oscillation cavity and an optical parameter laser oscillation cavity, and is characterized in that the pump laser oscillation cavity is used for generating pump laser; the pumping laser oscillation cavity comprises a pumping laser gain module, a pulse modulation module, a line width narrowing module, an optical isolation module, a first reflecting mirror and at least two second reflecting mirrors; the optical parametric laser oscillation cavity comprises an optical parametric oscillation nonlinear crystal module, a line width narrowing module, a first reflecting mirror and at least two third reflecting mirrors, the pumping laser oscillation cavity and the optical parameter laser oscillation cavity are both annular cavities and are nested with each other. The annular pump laser oscillation cavity and the optical parameter laser oscillation cavity are nested with each other, and high-stability simultaneous narrowing control of the pump laser line width and the wide tuning optical parameter signal laser line width is realized by using the same line width narrowing module, so that the requirement of wide tuning narrow line width intermediate infrared idler frequency light stable output is met.

This invention discloses a method and apparatus for detecting the linewidth of a narrow-linewidth laser. The method includes acquiring data information pre-collected using a data acquisition card; preprocessing the data information using a cumulative averaging algorithm; performing a fast Fourier transform on the preprocessed time-domain data information; processing the data using a moving average algorithm; fitting the moving averaged data using an L-M algorithm; and detecting the linewidth of the fitted data using a time-delayed self-heterodyne method to calculate the laser linewidth data. This invention uses a time-delayed fiber beat frequency method to measure the linewidth of a narrow-linewidth laser, which greatly enhances the accuracy of laser linewidth measurement while reducing the number of components used. This method uses a data acquisition card for data acquisition, fast Fourier transform for analysis and processing, and moving average and L-M algorithms for data processing, reducing costs while accurately detecting narrower laser linewidths.

Provided in the embodiments of the present application are a copper-grid-line solar cell and a preparation method therefor. When the copper-grid-line solar cell is prepared, a first exposure and a second exposure are sequentially performed on a photosensitive region of a negative photosensitive ink layer (700), wherein a laser line width and an energy density during the first exposure are both different from a laser line width and an energy density during the second exposure; development processing is then performed, so as to remove the part in a shading region and form gridline grooves; and electroplating processing is then performed, so as to form copper gridlines (800) in the gridline grooves.

The invention relates to the technical field of lasers, in particular to a line width adjustable distributed feedback fiber laser, which is characterized in that a phase shift grating and piezoelectric ceramics are mechanically coupled, and a signal generator is configured to output a voltage noise signal with adjustable amplitude or bandwidth to the piezoelectric ceramics so as to apply dynamic strain to the phase shift grating in the working process of laser, so that the phase shift grating can be subjected to dynamic strain; and the effective refractive index or pitch of the phase shift grating is changed, so that the line width of the output laser is broadened, and the controllable adjustment of the line width is realized. By applying a voltage noise signal to the piezoelectric ceramic, a dynamic pulling force can be applied to a phase-shift grating in the distributed feedback fiber laser to realize laser line width broadening of the distributed feedback fiber laser; the line width of the distributed feedback fiber laser can be controlled by applying voltage noise signals with different voltage amplitudes or different bandwidths to the piezoelectric ceramics.

The application provides a laser linewidth adaptive narrowing optical resonant cavity design method and system, temperature distribution data of an optical resonant cavity surface is collected, the temperature distribution data contains coordinate information and temperature values of each temperature measurement point; based on the temperature distribution data, a deformation gradient of the optical resonant cavity is calculated; the deformation gradient is linearly converted to generate an initial compensation signal, and based on a preset deformation threshold, an electrical compensation signal is obtained; according to the electrical compensation signal, an adjusted cavity mirror spacing is obtained; the deformation gradient is compensated by using the adjusted cavity mirror spacing to offset the instantaneous deformation, and the cavity structure of the optical resonant cavity is stably adjusted by using a preset thermal expansion coefficient, so as to cooperatively realize adaptive narrowing of the laser linewidth; the technical scheme provided by the application realizes dynamic adjustment of the cavity mirror spacing to compensate for the instantaneous thermal deformation, thereby adaptively narrowing the laser linewidth, and the frequency stability and output precision of the laser are improved.

The application discloses a chipped wavelength standard device and a preparation method thereof, and belongs to the field of wavelength standards. The device comprises a frequency discrimination module, a pumping module, a locking module and a substrate. The frequency discrimination module comprises a MEMS atomic gas chamber, a micro-ring resonant cavity and a photodetector; the pumping module mainly comprises a laser and a control circuit thereof; the locking module comprises a phase-locked amplifier, a reference signal source and a PID circuit. The substrate comprises a copper or ceramic heat sink and a TEC temperature controller. The application combines the micro-ring resonant cavity and the MEMS atomic gas chamber, directly pumps the micro-ring resonant cavity integrated optical path by the laser, locks the laser wavelength on the micro-ring resonant cavity resonance peak based on the micro-cavity self-injection locking method, reduces the laser noise and realizes the laser linewidth compression. The micro-cavity evanescent field excites the atomic transition in the atomic gas chamber, and the frequency is discriminated by detecting the fluorescence. The laser frequency is locked by controlling the laser current and the micro-cavity temperature through the frequency discrimination signal, and the chip-level wavelength metrology and value traceability are realized.

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 provides a mid-infrared laser linewidth measurement device and method based on a hollow-core anti-resonant fiber, and belongs to the technical field of precise laser parameter measurement. The device comprises a mid-infrared single-frequency laser, a first collimating lens, a beam splitter, an acousto-optic modulator, an aperture, a first mirror, a converging lens, a hollow-core anti-resonant fiber, a second collimating lens, a second mirror, a beam combiner, a photodetector and a spectrum analyzer. The method is as follows: after the laser is split, one path is frequency-shifted, and the other path is introduced into a time delay through the fiber; beat frequency signals are generated by interference of the two paths of light; and the linewidth is obtained through photoelectric conversion and spectrum analysis. The application takes a low-loss hollow-core anti-resonant fiber as a core delay element, solves the problem of difficulty in realizing long optical path delay in the mid-infrared waveband, has the advantages of compact structure, convenient adjustment, wide applicable waveband and high measurement precision, and is suitable for precise linewidth measurement of a 2-5 mu m single-frequency laser.

An integrated optical linewidth reduction system based on optical feedback and a low-speed electronic control loop to control the optical feedback. Light is tapped and reflected back to the laser with an amplitude, phase or both amplitude and phase adjustment such that the linewidth of the laser is lower than the free-running laser linewidth. The amplitude of the feedback signal may be controlled using an optical attenuator. The phase of the feedback signal may be controlled using a phase shifter. The amplitude of the optical feedback may be monitored by means of a filter and a photodetector, or just a photodetector. The amplitude and / or phase of the optical feedback is monitored by means of a frequency / phase noise discriminator. The phase shifter can be an endless phase shifter.

The invention discloses a narrow linewidth laser external cavity coupling system and a narrow linewidth laser external cavity coupling method based on linewidth test feedback, external cavity coupling is carried out by adopting a self-feedback mechanism, and through real-time feedback of optical power, the laser can be ensured to be in an optimal working state when the linewidth is measured, so that the accuracy of linewidth measurement can be improved, and the measurement accuracy is improved. Reliable data can be provided for subsequent adjustment of the position of the external cavity; after the line width measurement is completed, the outer cavity clamp displacement table can be controlled to adjust the position of the outer cavity of the narrow-line-width laser according to the line width until the line width of the laser output by the outer cavity reaches a preset target, and the optimal coupling position of the outer cavity can be determined; therefore, the optical power and the laser line width are integrated to perform external cavity coupling, the actual performance can be ensured to conform to the design index, the parameter consistency is ensured, the whole process is automatic and does not need personnel intervention, the subjective influence of operators is effectively avoided, and the process stability and the production efficiency are improved.

The invention discloses an image processing method and device for steel rail profile detection, and relates to the technical field of steel rail maintenance. The method comprises the following steps: based on an image brightness linear response coefficient calibration method, calculating according to environment illumination, a target gray value range and laser power to obtain an exposure time sequence, and carrying out image acquisition to obtain a steel rail profile image containing laser rays; based on the signal-to-noise ratio of the laser line, calculating according to the steel rail profile image to obtain the width of the laser line; based on a preset reference width, performing image fusion of multiple exposure times according to the laser line width, and extracting a laser center line image; based on a polynomial curve fitting method, performing segmentation and denoising processing according to the laser center line image to obtain a rail head center line image and a rail waist center line image; and splicing the rail head center line image and the rail waist center line image to obtain a processed steel rail profile image. The method is an efficient and accurate image processing method for steel rail profile detection.

According to the laser frequency locking device and method, the self-injection locking technology is introduced into the tunable laser, laser frequency locking is achieved in a wide tuning range in an all-optical feedback mode, a feedback control circuit does not need to be externally connected, miniaturization packaging can be achieved, the laser line width can be narrowed, and low-frequency noise can be restrained; and the channel switching speed can also be improved. Comprising a laser for outputting laser with tunable wavelength; the wavelength locker locks laser wavelengths output by the laser to a plurality of specified wavelengths and outputs the laser wavelengths, the wavelength locker comprises a filtering unit and an optical feedback unit, and the laser output by the laser is fed back to the laser through the optical feedback unit after being filtered by the filtering unit. The filtering unit is used for realizing self-injection locking of laser, a transmission spectrum or a reflection spectrum of the filtering unit is provided with a plurality of harmonic peaks respectively corresponding to the plurality of specified wavelengths, and the wavelength tuning range of the laser covers the plurality of specified wavelengths.

The application relates to the technical field of sensing, and discloses a demodulator chip with a phase noise compensation function and an optical fiber acoustic wave sensing system, which comprises an optical port module, a first polarization filter, a beam splitter module, a modulator, a coherent receiving module and a phase noise extraction module; the optical port module is used for acquiring an incident laser signal, outputting detection light, acquiring scattered light and coupling with a delay optical fiber; the first polarization filter is connected with the optical port module; the beam splitter module is connected with the first polarization filter; the beam splitter module is connected with the optical port module through the modulator; the coherent receiving module is connected with the beam splitter module; the coherent receiving module is connected with the optical port module; the beam splitter module is connected with the phase noise extraction module, and the phase noise extraction module is connected to the delay optical fiber; the phase noise extraction module is used for extracting phase noise through a delay self-coherence mode; the laser linewidth demand can be reduced, and the sensing performance under the same laser linewidth level can be improved.

This invention belongs to the field of optical communication and relates to a signal phase recovery method, apparatus, device, and medium based on maximum a posteriori probability symbol decision error. The method includes the following steps: performing symbol decision on the received signal based on maximum a posteriori probability and calculating the symbol decision error; constructing an error function based on the symbol decision error and calculating the gradient of the error function with respect to the phase noise value; updating the phase estimate along the gradient descent direction; and performing phase noise recovery of the symbol based on the phase estimate to obtain the phase-recovered output signal. Compared with existing technologies, this invention combines the error gradient descent algorithm with high-performance phase recovery to meet the compensation requirements for severe linear random phase noise generated by laser linewidth in coherent transmission. Simultaneously, the symbol decision error-based approach improves the accuracy of phase noise estimation while effectively avoiding the use of time windows, thus reducing computational complexity.

This invention belongs to the field of laser equipment technology, specifically disclosing an ultra-narrow linewidth vertical external cavity surface-emitting laser (VECS), including a laser resonator unit and an intracavity control unit. The laser resonator unit is used to generate laser oscillation, and the intracavity control unit is used to perform polarization control, mode control, wavelength tuning, and linewidth narrowing of the fundamental frequency light. The laser resonator unit includes a pump light emission system, a gain chip, a folded output mirror, and a back-end mirror. The intracavity control unit includes a beam splitter, a polarization element, a mode control element, a wavelength tuning element, a linewidth narrowing element, and an output coupling mirror. The second harmonic self-suppression of the mode control element is used to control the laser mode in the resonant cavity to achieve single-frequency lasing, which simplifies the design and adjustment difficulty of the mode control element in the resonant cavity of the VECS. The self-injection locking characteristic of the microcavity device in the linewidth narrowing element is used to narrow the output linewidth of the laser, which can achieve a deep narrowing of the laser linewidth and realize ultra-narrow linewidth output.

The invention provides a device and a method for measuring the line width of a laser, which can be applied to the technical field of laser. The measuring device comprises a filter which is configured to have a tunable transmission center wavelength so that the variable quantity of the transmission center wavelength covers the line width of a laser to be measured and filter output laser of the laser to be measured, a transmission spectrum of the filter has a predetermined line type and a predetermined line width, and an output spectrum of the laser has a predetermined line type; the detector is configured to detect the filtered laser to obtain the power of the output laser penetrating through the filter under different penetrating central wavelengths; the processor is configured to fit each transmission center wavelength and the power corresponding to each transmission center wavelength based on a predetermined line type to generate a power spectrum; and based on the line width of the power spectrum and the predetermined line width of the transmission spectrum, determining the line width of the output spectrum of the to-be-measured laser.