346 results about "Pulse duration" patented technology

The invention discloses a wavelength-adjustable high-power picosecond all-solid-state laser. The microchip seed source adopts a passive Q-switching principle, can directly generate laser with the pulse width as narrow as 300ps, is high in seed laser efficiency, good in beam quality and large in energy, can synchronously output TTL (transistor-transistor logic) level, and is used for controlling the pulse duration and delay of a 808nm QCW pumping source; the optical isolator protects the front-stage microchip solid laser from being damaged by returned light of the rear-stage amplifier; the single-rod two-way end pump amplifier amplifies laser pulse energy output by the microchip solid laser; the light beam shaper comprises a Galileo laser beam shrinking system and a soft edge diaphragm and is used for shaping light beams; the single-rod one-way end pump amplifier amplifies the pulse energy of the preceding-stage laser; and the frequency multiplier performs frequency conversion on the output laser, and outputs wavelength-adjustable picosecond laser with millifocus magnitude, high power and high beam quality.

The invention relates to the technical field of welding, in particular to a hot riveting welding head synchronous temperature control method and system based on the temperature change rate, and the method comprises the steps: executing full-power heating pulse triggering operation on a welding head, calculating the pulse duration according to a start timestamp and an end timestamp, calculating the temperature rise, and eliminating peak noise through a digital filtering algorithm; environment temperature and relative humidity are collected in real time, and equivalent heat capacity is calculated; the initial temperature difference between any welding heads is calculated, and a dynamic target temperature curve is constructed; and calculating an actual temperature change rate, synchronously extracting a target change rate of the dynamic target curve at a corresponding moment, calculating a change rate deviation between the two change rates, judging whether intervention adjustment is needed or not, calculating an output signal by using an incremental PID algorithm if intervention adjustment is needed, and adjusting the heating power according to the output signal. According to the scheme, the stability of the hot riveting welding quality is effectively improved by accurately quantifying the thermal characteristics of the heterogeneous welding head, dynamically planning a personalized temperature rising track and performing high-frequency closed-loop regulation and control.

A receiving device, comprising: a clock generator circuit configured to generate a base clock signal; a counter configured to count cycles or edges of the base clock signal while a measurement pulse is received over a one-wire serial bus during a first transaction conducted over the one-wire serial bus, the measurement pulse having a pulse duration defined by a number of clock cycles of a transmitter clock signal; and a controller configured to adjust a count value of the counter when the counter is timing actuation of a trigger using a correction value that represents a difference between the cycles or edges of the base clock signal counted while the measurement pulse was being received and the number of clock cycles of the transmitter clock signal that defines the pulse duration.

Embodiments of systems, devices, and methods relate to initiating beam transport for an accelerator system. An example method includes increasing a bias voltage of one or more electrodes of the accelerator system to a first voltage level and extracting a charged particle beam from a beam source such that the beam is transported through the accelerator system. The beam has a beam current at a first beam current level that results in a first transient voltage drop of the accelerator system within a threshold. The method further includes increasing the beam current at a rate that results in one or more subsequent transient voltage drops of the accelerator system until the accelerator system has reached nominal conditions. The one or more subsequent transient voltage drops are within the threshold. Another example method includes biasing one or more electrodes of an accelerator system to a voltage level and selectively extracting, according to a duty cycle function, a charged particle beam from a beam source such that the charged particle beam is transported through the accelerator system. The duty cycle function can be linear or non-linear and can include a frequency f. The duty cycle function can include a variable pulse duration such that the variable pulse duration increases over time with each selective extraction of the charged particle beam.

The invention discloses a ground wire deicing machine optimization method and system based on high-amplitude narrow-pulse-width electric pulses, and relates to the technical field of deicing machine optimization, and the method comprises the following steps: obtaining ice accumulation first data, and carrying out the type classification of ice layers, so as to obtain a swinging ice layer and a hard ice layer; if the ice layer type is a swinging ice layer, obtaining second data of the deicing environment and calculating an ice layer re-freezing occurrence probability, and carrying out secondary classification on the swinging ice layer according to the ice layer re-freezing occurrence probability; if the ice layer type is a hard ice layer, constructing a ground wire electric pulse deicing mathematical model based on the deicing environment second data and the icing first data, and obtaining an initial deicing machine pulse repetition frequency and an initial single pulse duration; respectively weakening the initial deicing machine pulse repetition frequency and the initial single pulse duration to obtain a corrected deicing machine pulse repetition frequency and a corrected single pulse duration; and deicing is carried out according to the corrected pulse repetition frequency of the deicing machine and the corrected single pulse duration, and the hard ice layer after deicing operation is converted into a swinging ice layer.

The invention discloses a medical cosmetology method and device based on a photoacoustic effect. Existing skin anti-wrinkle and anti-aging photoelectric equipment such as radio frequency and ultrasound has the problems of pain, discomfort, limited application depth, unstable flash type light source energy output and the like. According to the method, pulse laser with a specific wave band and pulse duration is utilized to irradiate the skin to generate a photoacoustic effect, 400-700nm of the pulse laser acts on a surface layer, 700-1300nm of the pulse laser can reach a deep layer of 50mm, collagen regeneration and wrinkle resistance are promoted, and the method is painless and radiation-free. The device comprises a laser generating part, a light splitting part, a combined lens part and the like, a controller coordinates all the parts to work, a steering engine adjusts a reflector to control the laser depth, and an ultrasonic sensor assists. The system has the advantages that energy is accurately controlled, the system is suitable for skin tissues of all layers, the defects in the prior art are effectively overcome, and a safer and more efficient new scheme is provided for the field of medical cosmetology.

An optical metrology device includes a selectable pump arm that is used to produce a transient response in the target sample and a probe arm and may be configured to perform static Magneto-Optic Kerr Effect (MOKE) measurements or ellipsometry measurements when the pump arm is not selected, and time resolved (TR) MOKE measurements or ellipsometry measurements when the pump arm is selected. The optical metrology device may be further configured to perform opto-acoustic measurements when the pump arm is selected. A pulse shaper in the pump arm may be used to pulse duration, phase, or both, of the incident pump beam to enable measurement of the dependence of the magnetic dynamics on the pump pulse characteristics. The optical metrology device may be configured to operate at a single selectable wavelength or multiple wavelengths in a continuous or discontinuous spectrum.

The invention relates to the technical field of cable fault detection, in particular to an insulation fault detection method, system and device for a flexible signal cable, and the method comprises the steps: obtaining the electromagnetic wave intensity of each position at different sampling moments in the working process of the flexible signal cable, extracting the local pulse segment of each high-frequency sequence, and obtaining the local pulse segment of each high-frequency sequence; constructing a pulse steep coefficient of each local pulse segment by combining the change degree of the electromagnetic wave intensity in each local pulse segment and the pulse duration; and analyzing the frequency range and the phase difference of the electromagnetic wave intensity in the frequency domain, and constructing the partial discharge frequency coefficient of each ultrahigh frequency sensor by combining the amplitude average level and the phase fluctuation, thereby obtaining the partial discharge characterization value of each ultrahigh frequency sensor so as to detect the insulation fault of the flexible signal cable. According to the invention, the influence of electromagnetic interference on insulation fault detection can be reduced, and the accuracy of insulation fault detection of the flexible signal cable is improved.

The invention provides an overcurrent protection circuit, a radio frequency front-end module, a power supply device and electronic equipment, the overcurrent protection circuit comprises a switch module, a detection module, a first timing module and a control module, the switch module is used for connecting the power supply module and a power utilization module in the radio frequency front-end module; the detection module is used for detecting the output current of the power supply module, and is also used for outputting a first trigger signal when the output current is greater than a first preset current threshold value; the first timing module performs timing when receiving the first trigger signal so as to obtain a first duration; the control module is used for controlling the switch module to be switched off when the first duration is larger than or equal to a first time threshold value so as to cut off power supply of the power module to the power utilization module, and the first time threshold value is larger than the single surge pulse duration of the power module. The over-current protection circuit can improve the reliability of the radio frequency front-end module.

According to the mask defect in-situ repairing method, the femtosecond laser is adopted for defect repairing, and all the advantages of the femtosecond laser are absorbed. Femtosecond laser is ultrashort pulse laser with'femtosecond 'as a time unit, the pulse duration time of the femtosecond laser is extremely short (femtosecond magnitude), and the peak power of the femtosecond laser is extremely high (the maximum can reach pat watt). Therefore, according to the repairing method, the repairing precision can be reduced to 15 nm, the heat affected zone is smaller than 1 micron, the repairing time can be shortened to 100 ms for the defect of 100 nm, the roughness of the repaired surface is smaller than or equal to 0.5 nm, meanwhile, the good effects of high repairing precision, low heat affected zone, high repairing speed, low equipment cost and simple operation are achieved, and the rejection rate of the mask is reduced. The method is especially suitable for repairing advanced process masks, such as EUV and ArF, and display panel masks, such as OLED and FMM, and MEMS device masks.

The invention relates to the technical field of single-photon detection, in particular to a single-photon detector performance parameter measurement method, device and equipment and a storage medium, and the method comprises the steps: building a statistical histogram of time domain interval data, and building the statistical distribution characteristics of the photon counting rate and dark counting of a single-photon detector; the probability of no photon detection event in the duration of the optical pulse and the ideal probability of no dark pulse in a preset time window are defined based on the statistical distribution characteristics, and then the probability of generating a single photon signal by the periodic optical pulse is calculated based on the obtained parameters; and finally, determining a periodic statistical peak count value based on the statistical histogram and the probability of generating the single photon signal by the periodic light pulse, and calculating an average detection photon number and a dark count rate so as to obtain the dead zone time, so that information such as the average detection photon number, the dark count rate and the dead zone time of the single photon detector is simultaneously represented through one-time data acquisition, and the detection accuracy of the single photon detector is improved. The problems that in a traditional method, the data storage amount is large, and cost is high are solved.

Methods for formation of graphene films, graphene films made thereby, and applications thereof. A method for the formation of a graphene film includes coating a polymeric graphene precursor on a substrate. The method includes irradiating the polymeric graphene precursor coated on the substrate with a pulsed high intensity light source emitting at more than a single wavelength and with a pulse duration of less than one second, to convert the polymeric graphene precursor to the graphene film.

This disclosure relates to an inertial sensor for measuring an inertial quantity along a sensing axis. The sensor comprises an atom interferometer comprising a pulse generator to generate one or more pulsed light beams, defined by a respective pulse duration to place atoms into a superposition, and re-combine the atoms to measure an interference of the atoms and calculate the inertial quantity based on the measured interference. The sensor further comprises an auxiliary acceleration sensor configured to measure acceleration transverse to one or more of the pulsed light beams; and a control system configured to calculate a transversal offset of the atoms relative to the pulsed light beams caused by the measured acceleration transverse to the one or more of the light beams, increase the pulse durations, and adjust the pulse timings to compensate for a reduced beam intensity applied to the atoms as a result of the transversal offset.

Disclosed herein is an electroporation system including a catheter shaft, at least one electrode coupled to the catheter shaft at a distal end thereof, and an electroporation generator coupled in communication with the at least one electrode. The electroporation generator configured to supply a biphasic pulse signal to the at least one electrode. The biphasic pulse signal includes a first phase having a first polarity and a first pulse duration, and a second phase having a second polarity opposite to the first polarity, and a second pulse duration. Each of the first phase and second phase has a voltage amplitude of at least 500 volts and a pulse duration of less than 20 microseconds. The second phase is generated at a non-zero interval following the first phase.

An audio authentication and identity verification system and method that encodes dynamic cryptographic information across the audible and inaudible spectrum (0 Hz→30 kHz, scalable to 124 kHz). A rolling acoustic signature simultaneously embeds identity, time, date, and GPS location using a hybrid of frequency shift keying (FSK), phase shift keying (PSK), Morse style pulse duration modulation, and time domain multiplexing. To guarantee post-event privacy and integrity, the system further incorporates a dual custody audio architecture in which every authenticated recording is split into complementary bit interleaved segments stored separately, and the decryption key is fragmented via Shamir 3-of-5 secret sharing—preventing unilateral access or tampering. The system establishes a tamper proof, real time, and offline capable authentication layer that functions in air, through conventional microphones, and via dedicated emitter hardware.

The invention provides a laser three-dimensional imaging system and method based on receiving and transmitting dual polarization modulation matching, and the method comprises the steps: enabling a pulse laser to transmit single-wavelength linear polarization pulse laser through a transmitting unit under the synchronous control of a transmitting unit controller, continuously rotating the laser linear polarization direction during the pulse duration, and enabling the laser linear polarization direction to be smaller than the single-wavelength linear polarization pulse laser; and finally, a laser pulse subjected to polarization modulation is emitted to a target through a laser beam expander. In the receiving unit, a telescopic optical system receives laser pulses returned from a target, the beam width is narrowed, wavelength selection is carried out through a wavelength filter, and the laser pulses pass through a polarization modulator of the receiving unit and are further decomposed to two orthogonal polarization directions through a polarization spectroscope. And the two groups of imaging objective lenses, the area array detector X and the area array detector Y are used for imaging and receiving. And finally, the digital signal processor carries out resolving processing on the digital signals obtained by the two detectors to obtain distance information of each point on the two-dimensional image plane. According to the invention, three-dimensional imaging with a longer distance, a higher resolution ratio and a higher speed is realized.

In accordance with an embodiment, a method for controlling a constant on-time switched mode power converter includes: generating a pulse signal having an on-time; during a soft-start phase of the power converter, successively increasing the on-time from an initial duration to a final duration, wherein the final duration is larger than the initial duration; sensing an output voltage of the power converter and generating a feedback signal proportional to the output voltage; adjusting a frequency of the pulse signal based on the feedback signal and a reference signal; and driving a power switch with the pulse signal to control the power switch and regulate the output voltage.

A keyboard system comprises a key structure including a key switch with a lighting element and phototransistor, and one or more processors that drive the lighting element for a first pulse duration. The output of the phototransistor is determined at the end of the first pulse duration, wherein the key structure is determined to be pressed when the output is below a first output value at an end of the first pulse duration, and unpressed when the output of the phototransistor is above a second output value at the end of the first pulse duration. A fall-time of the output during the first pulse duration is determined and the first pulse duration is calibrated to a second pulse duration when the fall time less than the first pulse duration, the second pulse duration being greater than the fall time and less than the first pulse duration.

A method and system for generating deep ultraviolet (DUV) laser light is disclosed, in one embodiment the DUV laser system includes a fiber laser source configured to emit a poised fundamental laser beam in the near-infrared with a pulse duration of less than 400 femtoseconds (fs), a nonlinear crystal assembly comprising first, second, and third nonlinear crystals that is configured to convert the fundamental laser beam to produce a fifth harmonic laser beam having a wavelength in a range from 200 nanometers (nm) to 230 nm, and at least one compensation plate disposed in at least one position preceding at least one of the first, second, and third nonlinear crystals and configured such that a pair of pulsed laser beams transmitted through the at least one compensation plate are spatially and temporally overlapped within the at least one of the first, second, and third nonlinear crystals.

A spacecraft thruster distribution and pulse width modulation method based on a dynamic inverse matrix comprises the following steps: calculating a torque matrix generated by each thruster in combination with the installation position, the thrust size and the thrust direction of the thruster; the control direction of each thruster is determined, and grouping is carried out according to the control directions of the thrusters; a thruster for controlling the three-axis positive direction is pre-selected, a torque matrix corresponding to the pre-selected three-axis positive axial thruster is generated, and the air injection pulse width duration of the three axes is calculated in combination with instruction control torque; according to the calculated symbol of the three-axis jet pulse width duration, reselecting a thruster, and obtaining a dynamic torque matrix of the reselected thruster; according to the instruction torque sent by the upper computer and the dynamic torque matrix of the reselected thrusters, the jet pulse width duration of each thruster is calculated based on a matrix inversion algorithm; the thruster pulse width modulation method is designed on the basis of considering the coupling influence of the three axes of the thruster, and can adapt to the large-range change of the mass center of the aircraft.

The application provides a method for regulating halogen perovskite microstructure at a frozen temperature by using a laser and an electric field, and relates to a device, which is a customized TEM in-situ sample rod equipped with a laser optical fiber and a liquid nitrogen Dewar bottle, and a Nd:YAG pulse laser system with a wavelength of 532 nm, adjustable pulse frequency and a pulse duration of 7 ns coupled into a transmission electron microscope through the optical fiber; first, at a frozen temperature, perovskite nanocrystals are etched by controlling the energy, frequency and action time of the pulse laser, then at the frozen temperature, the small crystal nucleus rotation of the perovskite nanocrystals is controlled by using a low-energy pulse laser and applying an electric field, and the perovskite nanocrystals are recrystallized along specific crystal faces, so that perovskite nanocrystals with specific exposed surfaces, reduced microstructure defects and increased radiation resistance are obtained, and the method has great value for large-scale industrial production.

A cancer treatment with improved effectiveness may feature emission of radiant energy from a laser source based upon measured parameters, particularly melanin content, in a patient's surrounding tissues. Multiple wavelengths of radiant energy, pulse durations, and intensities may be utilized in the radiant energy emission based upon the patient's tissue parameters. One embodiment of a laser source features multiple laser modules (201) which may be independently operated and adjusted for intensity and active duration.

A method for treating a metal substrate includes generating a beam from a single laser having a pulse duration less than 800 femtoseconds and a wavelength greater than 700 nanometers. The beam is split via a diffractive optical element to establish first and second separated beams angled away from each other. An optical prism alters respective pitches of the separated beams, and a focal lens receives the altered beams to angle them toward each other at or near a single focal point on the metal substrate. The combined laser irradiation from the altered, separated beams affects the metal substrate to concurrently form a plurality of microstructures and nanostructures thereon.

The present invention relates to a method and to a device for correcting the shape of an optical component (1) using pulsed laser radiation. For this purpose, the component (1) is measured and excess material (7) is determined by way of comparison with a target geometry (6) and is at least partially removed by machining using at least one pulsed laser beam (4) with pulse durations of > 1 μs in order to at least approximate the actual geometry (5) to the target geometry (6). During machining, the component (1) is rotated at a rotational speed about an axis of rotation, wherein the distance of the laser beam (4) to the axis of rotation is changed at least temporarily. The rotational speed, the beam diameter of the laser beam (4) on the component (1) and the temporal pulse interval between the pulses of the laser beam (4) are selected such that material regions of the component (1) removed by successive pulses of the laser beam (4) do not overlap.

The invention relates to the field of non-invasive monitoring, and particularly provides a method for evaluating vascular elasticity through radial artery pulse waves. The method comprises the following steps that 1, radial artery pulse waves are obtained; step 2, preprocessing the radial artery pulse wave to obtain an average pulse period; 3, calculating a dominant wave angle based on the average pulse period; step 4, calculating pulse duration based on the average pulse period; step 5, calculating rise time based on the average pulse cycle; step 6, calculating a main wave amplitude based on the average pulse period; step 7, calculating a waveform area based on the average pulse period; and 8, establishing an evaluation model, inputting the dominant wave angle, the pulse duration, the rise time, the dominant wave amplitude and the waveform area into the evaluation model, and outputting a vascular elasticity predicted value by the evaluation model. According to the method, the accuracy of predicting the vascular elasticity is high, and the cost is low.

A method and apparatus for inscribing a high-temperature stable Bragg grating in an optical waveguide, comprising the steps of: providing the optical waveguide; providing electromagnetic radiation from an ultrashort pulse duration laser, wherein the wavelength of the electromagnetic radiation has a characteristic wavelength in the wavelength range from 150 nanometers (nm) to 2.0 micrometers (μm); providing cylindrical focusing optics; providing a diffractive optical element that when exposed to the focused ultrashort laser pulse, creates an interference pattern on the optical waveguide, wherein the irradiation step comprises irradiating a surface of the diffractive optical element with the focused electromagnetic radiation, the electromagnetic radiation incident on the optical waveguide, from the diffractive optical element, being sufficiently intensive to cause permanent (Type II) change in the index of refraction within multiple Bragg grating planes in the core of the optical waveguide resulting from at least one micropore.

Apparatus and method for managing data in a non-volatile memory (NVM) having an array of ferroelectric memory cells (FMEs). A data set received from an external client device is programmed to a group of the FMEs at a target location in the NVM using a selected profile. The selected profile provides different program characteristics, such as applied voltage magnitude and pulse duration, to achieve desired levels of power used during the program operation, endurance of the data set, and latency effects associated with a subsequent read operation to retrieve the data set. The profile may be selected from among a plurality of profiles for different operational conditions. The ferroelectric NVM may form a portion of a solid-state drive (SSD) storage device. Different types of FMEs may be utilized including ferroelectric tunneling junctions (FTJs), ferroelectric random access memory (FeRAM), and ferroelectric field effect transistors (FeFETs).

We present a ground-based laser system for searching, ranging, and tracking that actively illuminates small resident space objects (RSOs) in low Earth orbit (LEO) and observes position and transit-time of reflections, enabling orbital custody of most one-to-few centimeter-sized objects. A diode-pumped alkali laser (DPAL) augmented with mode-locking and Q-switching serves as an illuminator and offers exceptionally high spectral brightness due to its output beam's sub-nanosecond pulse duration and picometer-level spectral linewidth. Kilohertz fast-rastering enables interrogations of distinct few-meter-sized sky-patches at megahertz rates. Paired on the observation side with one or more telescopes outfitted with Faraday anomalous dispersion optical filters (FADOFs), image intensifiers, multi-pixel arrays, and nanosecond timing, the combined system could offer nearly background-free discoveries of RSOs every hour, even during daytime. Periodically re-flashing previously discovered objects to maintain orbit custody expends only a small fraction of total observing time.

The invention discloses a converter transformer fault diagnosis method and system based on voiceprints and thermal signals, and the method comprises the steps: carrying out the time-frequency decomposition of each voiceprint original signal data and temperature thermal signal data of a converter transformer, and obtaining a sound time-frequency matrix and a temperature time-frequency matrix; the kurtosis and the sound pulse duration of the time-frequency matrix of the sound are calculated to serve as basic time-frequency characteristics of the sound; calculating an energy gradient and an entropy change rate of the time-frequency matrix of the temperature as basic time-frequency characteristics; coupling characteristics of the time-frequency matrixes of the sound and the temperature in the same frequency band are extracted; performing feature screening on all basic time-frequency features and coupling features by calculating a maximum mutual information coefficient, and outputting an optimal feature subset; and constructing a converter transformer fault diagnosis-oriented identification model fusing ensemble learning and random forest, and training the identification model according to the optimal feature subsets in different operation states to perform fault diagnosis. The fault risk sensing capability of the converter transformer can be effectively improved.

The invention relates to a method for producing a material board having at least one layer comprising at least a portion of natural fibers, wherein at least one of the at least one layer comprises a useful product made from a raw material comprising natural fibers, wherein the method comprises at least the following steps: i) providing a system for producing a material board, at least comprising: material preparation, gluing, shaping, pressing, and finishing, iii) breaking down the raw material under the action of a pressure shock wave having a pulse duration and a pulse frequency into at least a first, odd-indexed component and a second, even-indexed component using at least one device for breaking down the raw material under the action of a pressure shock wave having a pulse duration and a pulse frequency,iv) Separating the first, odd-indexed component and the second, even-indexed component based on at least one parameter. v) Making the (at least one) obtained odd-indexed component available for use in at least one further process step of the method. In order to be able to produce material plates in an environmentally friendly and cost-effective manner, among other things, it is proposed to provide the following step: vi) Disassembling at least one of the even-indexed components under the influence of a pressure shock wave having a pulse duration and a pulse frequency, such that at least one further odd-indexed component is created.