17 results about "Laser modulation" patented technology

An optical device includes a generator, a light emitter, a modulator, an optical amplifier, a current source, a storage, and a controller. The generator generates an electric signal of a multilevel amplitude modulation method. The light emitter emits laser light. The modulator modulates the laser light using the electric signal and outputs an optical signal. The optical amplifier optically amplifies the modulated optical signal according to a drive current. The current source adjusts the drive current to be supplied to the optical amplifier. The storage previously stores an information with respect to input-output characteristics of the optical signal in the optical amplifier relative to drive current value of the drive current. The controller acquires, from the storage, the input-output characteristics corresponding to the drive current value of the drive current supplied to the optical amplifier and controls the electric signal based on the acquired input-output characteristics.

The application relates to the technical field of magnetic field measurement, in particular to a double-frequency resonance locking system of an NMOR atomic magnetometer based on FPGA, which comprises an FPGA, a laser modulation driving unit and a signal acquisition and processing unit, a homologous synchronous reference signal source, a first demodulation branch and a second demodulation branch are arranged in the FPGA, signals corresponding to a single Larmor frequency and double Larmor frequency are synchronously demodulated respectively to obtain corresponding in-phase signals and quadrature signals. The FPGA determines corresponding weight coefficients according to the output signals of the two demodulation branches, fuses corresponding frequency correction amounts and obtains a frequency control amount to adjust the laser modulation frequency. The system is also provided with a frequency sweeping and peak searching logic and a host computer parameter configuration module. The application is used for realizing that there is always a feedback signal with sufficient signal-to-noise ratio in the whole space range, so that the measurement blind area of the single-frequency NMOR magnetometer is eliminated.

The application discloses a tuning fork type optical fiber photoacoustic spectrum detection method and device, and belongs to the technical field of spectrum detection, which comprises a tuning fork, a first detection optical fiber and a second detection optical fiber, the tuning fork is arranged in a to-be-detected gas environment, and the two detection optical fibers respectively form Fabry-Perot cavities with the outer surfaces of two vibration arms of the tuning fork. The method comprises the following steps: after modulating excitation laser, the modulated excitation laser is incident to the gap between the two vibration arms of the tuning fork, and the to-be-detected gas absorbs the modulated excitation laser to generate a photoacoustic signal; the photoacoustic signal drives the two vibration arms of the tuning fork to generate mechanical vibration, so that the cavity lengths of the two Fabry-Perot cavities change; the change amounts of the corresponding reflected interference spectra of the two Fabry-Perot cavities when the cavity lengths change are detected respectively, the change amounts of the two obtained reflected interference spectra are added, a harmonic signal is extracted, and the concentration information of the to-be-detected gas is inversely calculated through the amplitude of the harmonic signal. The spectrum detection method and device are high in sensitivity, high in accuracy, low in cost, easy to integrate, capable of resisting electromagnetic interference and suitable for long-distance detection.

The present application relates to the technical field of transformer on-line monitoring, in particular to a transformer oil quality analysis photoacoustic spectrum detection system and method. The method extracts transformer oil sample through a circulating oil pump, and removes dissolved gas in the oil by using an oil-gas separation membrane assembly under a negative pressure environment. After preheating by a spiral coil, the removed gas is filtered and homogenized by a micro-porous membrane structure, and then sent into a resonant photoacoustic cell. A main controller dynamically adjusts a laser modulation frequency according to a gas flow rate, so as to maintain the stability of an acoustic resonance field in the resonant photoacoustic cell. The modulation laser excites the measured gas to generate a photoacoustic signal, and after collection and processing, the concentration of the multi-component dissolved gas is decoupled and calculated, and the transformer fault early warning is carried out accordingly. The present application has the advantages of stable degassing, high detection sensitivity, strong anti-interference ability, and suitability for multi-component continuous detection.

This invention provides a non-invasive stimulation device based on acoustic field modulation using a concave fiber bundle. The device comprises a pulsed laser module, a laser modulation control module, a multi-channel concave fiber bundle, and a photoacoustic transducer coating. The pulsed laser, after processing by the modulation module, is input into the fiber bundle. Its output end is concave, and the photoacoustic transducer coating on the surface converts the laser into ultrasonic waves. The concave structure achieves initial geometric focusing of the ultrasonic waves, forming the geometric focus of the acoustic field. The modulation module has control channels corresponding one-to-one with the fiber transmission channels, allowing for dual-dimensional control of the emission time delay and pulse intensity of each channel's pulsed laser. This enables hardware-free axial and lateral scanning of the focus; intensity control maximizes the focus sound pressure and minimizes the sidelobe sound pressure. This invention significantly improves sound pressure gain and spatial resolution through the combination of concave fiber bundle geometric focusing and a high-efficiency photoacoustic transducer coating.

An optical microscope contains a light source that emits coherent laser light with a wavelength of less than 550 nm; an optical system; and an electronic module. The microscope generates two copies of the laser light, modulates the phase or amplitude of the first copy relative to the second copy, and recombines the first and second copies to form an excitation beam. The microscope focuses the excitation beam onto a position on a material and measures a response beam from the material using an optical detector. The response beam contains transmitted and reflected light from the material. The microscope extracts a response signal from the response beam, which represents a nonlinear optical response of the material and indicates a property of the material. The optical detector is a semiconductor photodiode. The type of semiconductor photodiode is selected based on the photon energy of the laser beam.

The application relates to the field of laser cutting, and particularly provides a laser cutting machine light path coaxial calibration device and method.The device comprises: a calibration module body provided with a mechanical interface consistent with a cutting head nozzle mounting interface; a radial polarized light modulation module fixed in the body and used for modulating laser into radial polarized light; an annular polarization sensor array fixed in the body and located downstream of the modulation module, comprising a plurality of polarization sensors uniformly distributed along a circumference, each sensor detection surface is located on an array inner wall surface, used for detecting a polarization angle in a respective direction and outputting a signal, and a geometric center of the array represents a nozzle theoretical axis position during calibration module installation; and a data processing and display module in communication connection with each sensor, used for calculating an offset amount of a laser beam center relative to the geometric center based on the polarization angle signal and visually outputting. The application improves the precision and efficiency of laser cutting machine light path coaxial calibration.

The application discloses a micropore array laser processing system and a processing method, and relates to the technical field of laser micro-nano manufacturing. The micropore array laser processing system comprises a light source system, a modulation beam splitting module, a telecentric acousto-optic scanning module, a two-dimensional galvanometer system, an f-θ field lens and a processing platform. The light source system is used for outputting a single high-power laser. The modulation beam splitting module is arranged on the outgoing optical axis of the light source system and is used for dynamically splitting the single high-power laser into a laser beam array. The telecentric acousto-optic scanning module is arranged on the outgoing optical axis of the modulation beam splitting module. The two-dimensional galvanometer system is arranged on the outgoing optical axis of the telecentric acousto-optic scanning module. The f-θ field lens is arranged on the outgoing optical axis of the two-dimensional galvanometer system. The processing platform is used for positioning a workpiece to be processed, and the processing platform is within the outgoing optical axis range of the f-θ field lens, so that high-efficiency and high-precision processing of array micropores can be realized through the laser beam array.

The application discloses a SPR phase imaging system based on an inclination angle spectrum, comprising: an incident light path for generating a surface array laser and being incident at a preset inclination angle; an SPR module for receiving the surface array laser and performing SPR sensing to obtain a surface array laser modulation result related to a substance to be measured; an imaging light path for spatially amplifying and light filtering the modulation result to form an image on a four-polarization array; a data processing unit for performing matched filtering and double-differential phase calculation on the four-polarization image to obtain a preliminary imaging result; constructing an SPR imaging process equivalent model based on the measured light field intensity information containing the inclination angle of the four-polarization array, inputting the preliminary imaging result into the model to obtain the light field information of p-polarized light, and performing inclination angle spectrum modeling and reverse propagation on the light field information of the p-polarized light based on an angle spectrum propagation theory to obtain a clear imaging result. The application improves the global spatial resolution under a large field of view to the level of a focusing region.

The application relates to the technical field of acceleration detection by using optical force, and discloses an optical force accelerometer based on spin cooling and a use method, which realizes acceleration detection by using laser-suspended microspheres, and improves detection precision by using the spin cooling effect of the microspheres in an optical field to inhibit thermal motion of the microspheres. Laser is processed into circularly polarized light suitable for capture and rotation driving by a laser modulation unit, and is input into a capture cooling unit; the capture cooling unit utilizes a potential well formed by an optical field to realize capture and rotation cooling of microparticles, simultaneously outputs laser carrying state information of the microparticles, and a displacement detection unit realizes acceleration response output by analyzing and monitoring the displacement state of the microparticles in real time through analysis of outgoing laser; a test unit provides auxiliary illumination and completes visual observation of behaviors of the microparticles, and together forms an optical capture and measurement system. The spin cooling method is adopted to realize cooling of a sensitive mass of the optical force accelerometer, the structure of a cooling system is simplified, performance requirements are reduced, practical potential is high, and cost is low.

This invention relates to the field of noise reduction technology, specifically to an AI-based intelligent noise reduction method for laser-modulated speech, comprising the following steps: Analog-to-digital conversion: A high-speed, high-precision analog-to-digital conversion module is used to convert analog data into digital signals, and noise reduction is performed only on human voices according to the usage scenario; Digital filtering: Bandpass filtering technology is used to filter out all out-of-band signals; AI intelligent processing: Spectral subtraction is used to eliminate background noise. By constructing a collaborative processing link of "high-precision analog-to-digital / digital-to-analog conversion—64th-order narrow transition band FIR filtering—dynamic spectral subtraction based on AI model library", for slow-changing and stable specific background noise such as mechanical vibration thermal noise of the laser itself and ambient optical path scattering interference, a 10-millisecond non-overlapping time slice and a joint decision mechanism of three parameters (mean, variance, and entropy) of Mel frequency cepstral coefficients are used to achieve accurate dynamic tracking of noise targets and adaptive stripping of speech signals.

This invention provides a multiphoton, multichannel optical measurement device for fiber characteristics in lung adenocarcinoma, comprising a laser modulation and scanning unit, a multichannel spectrophotometer, and a fiber characteristic measurement and classification unit connected sequentially by optical paths or signals. The laser modulation and scanning unit is configured to output femtosecond pulsed laser light to excite a sample to generate a nonlinear optical radiation signal through two-dimensional scanning, and to collect the backpropagating nonlinear optical radiation signal generated by the sample. The multichannel spectrophotometer is configured to perform spectral separation on the nonlinear optical radiation signal to form at least two independent optical detection channels, perform synchronous quantitative measurement of light intensity, and obtain optical radiation parameters of the corresponding wavelength band. The fiber characteristic measurement and classification unit is configured to extract the structural characteristic parameters of the two types of fibers and calculate the spatial distribution relationship characteristic parameters of the two types of fibers, and generate classification characteristic data characterizing the differences in fiber spatial configuration through a pre-trained classification model.

The present application relates to the technical field of laser cutting, in particular to a metal material laser cutting device and process for sheet metal production, comprising a processing bed, a moving device and a laser device, the laser device is installed above the processing bed through the moving device, further comprising a laser modulation mechanism installed below the laser head of the laser device, the laser modulation mechanism comprises a mounting ring, a suspended flow guide ring, an inertial pendulum ring and a universal connecting rod. The present application can produce pre-compensation in advance when the cutting head turns through the linkage of the inertial pendulum ring and the suspended flow guide ring, and automatically returns to the normal position through the pressure difference of the flow field formed by the water column deflection, so as to suppress the lateral tail of the water column. At the same time, the stable spiral flow field formed by the spiral turbulence sleeve around the water column can constrain its cross section, and the circumferential self-rotation of the water column is adaptively damped by the reverse inertia despinning sleeve, effectively solving the problem of precision decline caused by unstable water column during high-speed complex trajectory cutting of water jet laser.

The application provides a recoil displacement detection device and method for a gun barrel, the gun barrel is connected to a barrel seat; the device comprises a detection device main body and a laser reflection ruler arranged at the breech of the gun barrel; the detection device main body comprises a signal acquisition module and a laser modulation and demodulation module; the signal acquisition module is configured to emit a laser signal to the laser reflection ruler; the laser reflection ruler is used for forming a modulated reflection of the laser signal to form a reflected light signal; the reflected light signal is received and converted into an electric signal by a photoelectric detector; and the electric signal is transmitted to the laser modulation and demodulation module; the laser modulation unit is configured to receive a first pulse signal and a second pulse signal; the laser demodulation unit is configured to receive the reflected light signal; based on the reflected light signal, a detection signal is generated; and the detection signal is used for determining the recoil displacement information of the gun barrel, so as to solve the problem that the current recoil displacement detection of the gun mainly adopts an artificial detection mode, resulting in low detection efficiency and precision.