107results about How to "Pulse width adjustable" patented technology

The invention discloses a double-beam multi-functional z scanning optical non-linear measuring device and a double-beam multi-functional z scanning optical non-linear measuring device method. The device uses two light sources and can conveniently switch the light sources; an adjustable attenuation slice is adopted, so laser power is continuously adjustable from 0 and 100 percent; an acoustic optical modulator and a signal generator are adopted, so the pulse width and pulse period of emergent laser are adjustable; and transmission open hole and transmission closed hole data of a sample can be measured and reflecting open hole and transmission open hole data of the sample can also be measured. The device and the method not only can measure nonlinear absorption coefficient and nonlinear refractive index of a transparent sample, but also can measure nonlinear refractive index of a nontransparent sample; and a cold light source serving as an illumination light source is added into the device, a CCD camera is used for observing surface appearance of the sample and an optical filter is used for filtering the effect of the laser, so the measuring accuracy and correctness of the nonlinear absorption coefficient and nonlinear refractive index of the transparent sample and a partially transparent sample are enhanced.

The invention provides a GPS clock synchronization method for a distributed acoustic positioning system, which comprises the steps of: A. when GPS standard time is same as the preset synchronization time, synchronizing by a GPS second pulse triggering system, i.e. establishing time synchronization; B. after the synchronization is begun, according to preset clockc cycle and pulse width, generating a clock signal clkl by common crystal oscillation frequency division, and then generating synchronization pulses with corresponding pulse period and pulse width by clkl frequency division in a synchronizer; and C. when the number of the synchronization pulses reaches the preset number, triggering a GPS second pulse signal to generate a forced zero clearing signal so that all counters count again to eliminate cumulative errors caused by inaccurate common crystal oscillation. The invention is used in the distributed acoustic positioning system and can realize high-precise synchronization among all nodes, less power consumption and low cost.

The invention relates to a z scanning optical nonlinear measurement device and method capable of observing and monitoring in real time. The device mainly comprises a light source modulating and monitoring part, a data collecting part and a luminance observing part. The device adopts two light sources, so that the light sources can be switched conveniently, the pulse width and the pulse period of an emitted laser can be controlled through a signal generator, and the power is adjustable; the data of a transmission open hole and a transmission closed hole of a measured sample can be measured; and the data of a reflection open hole can be measured. According to the invention, the device and the method are suitable for not only the measurement of the nonlinear absorption coefficient and the nonlinear refractive index of a transparent material, but also the nonlinear measurement of an opaque material. A micro-objective, a lighting source and a CCD (Charge Coupled Device) camera are added for a sample moving platform in the device, so that the surface feature of the sample can be observed in real time, and the impact on the measurement data caused by the change of the feather of the sample can be avoided. While an oscilloscope is added to monitor the wave form and the power of the acting laser in real time, and the precision and the accuracy of the nonlinear measurement of material are improved.

The invention discloses an intelligent LED (light-emitting diode) video synchronizing impulse stroboscopic supplemental lighting device. The device is composed of an electronic circuit and a shell, wherein the electronic circuit has the following structure: a 220V alternating current is connected with a 24V switching power supply and a synchronization generator, the 24V switching power supply is connected with an LED lamp matrix and a +12V power supply circuit, the +12V power supply circuit is connected with a +5V power supply circuit, a light ray detection circuit is connected with a signal processing circuit, a signal input circuit is connected with the signal processing circuit, the signal processing circuit is connected with a signal output circuit, and the signal output circuit is connected with the LED lamp matrix through an actuator. With the adoption of the device provided by the invention, the phenomena of dazzling, uneven exposure and streaking can be effectively avoided, the synchronous exposure with a frame of a camera and frequency multiplication output of light can be realized, and the problem that the color of the red light in an image shot by a monitoring camera changes from red to yellow during the red light signal of traffic lights is solved.

The invention relates to an explosive detonation property testing system under a pulse high voltage and a tested explosive loading part. The microseond-stage pulse high voltage of the required pulse width is generated by a capacitive energy storage and charging unit and a pulse width control unit, and applied to the tested explosive loading part; then, a tested explosive is ignited by an ignition and explosion propagation unit in time sequence; and finally the high voltage resistance, the time sequence ignition stability, the detonation output property and the like of the tested explosive are measured by utilizing a detonating velocity and detonation voltage testing unit and a high voltage resistant testing unit under the microseond-stage pulse high voltage condition of the required pulse width. The explosive detonation property testing system and the tested explosive loading part are applicable to the explosive detonation property testing under the pulse high voltage, and have the characteristics of low cost, simple structure, adjustable pulse width and the like.

The invention provides a high power factor soft switching three-phase induction coil synthetic heating power supply, three groups of single-phase conversion circuits are adopted, each single-phase conversion circuit adopts a single-phase line for voltage input and adopts a single-phase line voltage diode for rectification respectively, a capacitor is not added for filtering, high-frequency alternating current pulse voltage which can enable output envelope lines to be sine waves and adjust the pulse width is formed by conversion through an inverter circuit, the high-frequency alternating current pulse voltage is inputted into three induction coils which are independent mutually and wound in parallel through resonant load matching of three groups of high-frequency transformers to form synthetic magnetic flux, and eddy current is generated in a workpiece which is heated for heating. Inverter bridges adopt the phase shift power control soft switching technology. Sine wave current outputted by the three single-phase inverter bridges are sampled and converted to alternating current voltage signals, the series connection is adopted for connecting the same frequency and the same phase for addition, square wave signals are formed through a zero-crossing comparison circuit, output pulses can track input square waves through a phase-locked loop circuit, three inverter bridge switching tubes are controlled through a power amplification circuit, a pulse distribution circuit and a driving circuit, and the phase-locked frequency tracking synchronization control is realized.

The invention discloses an all-fiber structural laser system capable of generating high-energy wave-free split rectangular pulse, which aims to solve the technical problems that the current erbium-doped fiber laser has low pulse energy and poor stability and is difficult to realize rectangular pulse output. The all-fiber structural laser system comprises two wavelength division multiplexers, an erbium-doped fiber, a first polarization controller, a polarization dependent isolator, a second polarization controller and an output coupler connected in turn through an intra-cavity single mode fiber, wherein the input ends of the two wavelength division multiplexers are provided with pumping light sources. The length of the erbium-doped fiber is 10 to 20 meters, the total length of the single mode fiber is 5 to 10 meters, and the whole intra-cavity net dispersion is kept in a large positive value. The all-fiber structural laser system has the advantages of simple structure, low price, good stability and the like on application; and compared with a solid laser for generating high-energy rectangular pulse, the all-fiber structural laser system has the advantages of high pumping efficiency, adjustment convenience, good pulse quality and the like, and is easy for fiber coupling.

The invention discloses a square wave generating circuit comprising a high-voltage direct current source, a tank circuit, a semiconductor switch, a charge resistor and a pulse output end used for loading tested equipment under test. Resistance value of the charge resistor can be reasonably selected by connecting the charge resistor in parallel on the pulse output end, so that charging time of semiconductor switch junction capacity can be greatly shortened, and a steep square-wave pulse of a falling edge can be realized; and meanwhile, a high-energy square-wave pulse with adjustable pulse width and level amplitude can be outputted by controlling closing time of the semiconductor switch, wide-range pulse adjustment from nanosecond level to millisecond level can be realized, and square wave generating circuit has the advantages of wide pulse adjustable range, level amplitude, convenience in control, reliable circuit and the like.

The invention discloses a laser dazzler with an adjustable laser beam divergence angle. The laser dazzler comprises a laser emitting device, a concave lens, a convex lens, a transmission motor and a control circuit; the laser emitting device, the concave lens and the convex lens are placed in sequence from left to right and are positioned on the same axis; the distance position between the laser emitting device and the concave lens is fixed, and the distance between the concave lens and the convex lens is changed through the movement of the convex lens; a control circuit comprises a laser emitting module and a motor control module; the laser emitting module is connected with the laser emitting device; the motor control module is connected with the transmission motor. The control circuit ofthe laser dazzler with the adjustable laser beam divergence angle can realize the functions of adjusting pulse frequency, pulse width and emitting power by changing the duty cycle of a driving signalof the laser emitting device.

The invention relates to a semiconductor-laser narrow pulse driving circuit and a working method thereof. The semiconductor-laser narrow pulse driving circuit comprises an external power supply interface circuit, a narrow pulse generating circuit and a MOSFET pulse driving circuit. The external power supply interface circuit provides power for the narrow pulse generating circuit and the MOSFET pulse driving circuit respectively. Through controlling a pulse width and a repetition frequency of a narrow pulse generating circuit trigger signal, a semiconductor laser can acquire a light pulse signal with the continuous adjustable pulse width and the repetition frequency. The trigger signal generated by the narrow pulse generating circuit directly drives a drain electrode switch of a MOSFET driving chip field effect transistor and a grid electrode of the field effect transistor is connected to a stable voltage so that a problem that signal rise time and fall time are too long when a pulse signal is directly used to drive the grid electrode of the field effect transistor can be avoided.

The invention provides a shift register unit, a signal generation unit circuit, a driving method and a display device. The shift register unit comprises a first node control circuit, a second node control circuit and an output circuit. The first node control circuit is used for controlling the potential of a first node. A second node control circuit controls the potential of the second node; and the output circuit is used for controlling and maintaining the potential of the first node and the potential of the second node, controlling the output end to be communicated with the second clock signal end under the control of the potential of the first node, and controlling the output end to be communicated with the second voltage end under the control of the potential of the second node. According to the invention, multi-pulse signals can be output, and the pulse number and the pulse width can be adjusted so as to correspond to threshold voltage compensation time required by different internal compensation circuits.

An object of the invention is to suppress the amount of heat generated by a light emitting diode and prevent the light emitting diode from being overheated without reducing the amount of emitted light even when the light emitting diode is a high-power light emitting diode. A light emitting device is configured so that one or more light emitting diodes 11 are lighted by a lighting circuit 12. A DC power is converted into a pulse power by a switching regulator 13 of this lighting circuit 12 and the voltage of a pulse power converted by this switching regulator is lowered by an output control portion 14. The pulse width of a pulse power lowered in voltage by this output control portion is adjusted by a pulse width adjusting oscillation means 16, and the current of a pulse power adjusted in pulse width by this pulse width adjusting oscillation means is limited by a limiting resistor 17. The light emitting device is configured so that a pulse power limited in current by this limiting resistor is outputted to a light emitting diode.

The invention discloses a device and method for detecting the thickness of a thermal barrier coating through employing a laser transmission method to excite an IR thermal wave, and the device comprises a signal generator, a power amplifier, a pulse laser, an IR thermal imager and an industrial control computer. The method comprises the steps: employing low-power and high-power pulse laser to carry out the thermal excitation of a thermal barrier coating base body side; collecting the temperature information of the coating side through the IR thermal imager; carrying out the linear fitting of the temperature difference-frame number curve data points under the two types of power; solving the slope and intercept of the fitting line; substituting the thermal diffusivity of the thermal barrier coating and the collection frame frequency of the IR thermal wave, and calculating and obtaining the thickness of the thermal barrier coating. The method overcomes the limitation of a conventional method for detecting the thickness of a thermal barrier coating through employing a coating side flash lamp for the thermal excitation of an IR thermal wave, and the surface of the coating does not need to be painted, so there is no paint layer thickness error and paint pollution risks. The method is wide in application range, and can test the thickness of an alloy base body thermal barrier coating with the poor thermal conductivity and big thickness. Meanwhile, the method employs a non-contact mode, is large in observation area, and is high in accuracy.

The invention provides a multi-module pulsed power supply based on energy storage of high-temperature super-conduction pulsing transformers, and belongs to the technical field of pulse power. The multi-module pulsed power supply comprises two or more than two single-module pulsed power supplies, wherein each single-module pulsed power supply consists of primary charging power supplies, discharging switches, a high-temperature super-conduction pulsing transformer, a power diode, a pulsed capacitor and a load; the primary charging power supplies of each single-module pulsed power supply are connected to two ends of a primary winding of the corresponding high-temperature super-conduction pulsed transformer through the corresponding switches in parallel; and each power diode and the corresponding load are serially connected with a secondary winding of the corresponding high-temperature super-conduction pulsed transformer to form a loop. The multi-module pulsed power supply is characterized in that the single-module pulsed power supplies are connected to one another in parallel, and each single-module pulsed power supply is connected with the corresponding pulsed capacitor through a switching circuit switch and is connected with a one-way conduction unit in parallel. The multi-module pulsed power supply based on energy storage of the high-temperature super-conduction pulsing transformers has the advantages that the transmission efficiency is high, pulse amplitudes and pulse widths of outputting current are adjustable, and the voltage of a discharging end of the primary winding is low.

An impulse generation circuit is provided for generating an impulse using a transmission line. Impulse characteristics of the impulse generation circuit are varied with the length of a transmission line rather than the characteristic variation of various devices used therein. The length of the transmission line is adjusted, such that a width of a generated pulse is adjusted. Because an end of the transmission line is short-circuited, the transmission line length can be easily adjusted on a substrate, and a ringing phenomenon due to re-reflection can be removed using termination impedance.

A management circuit for a self-powered microprocessor protection device microprocessor comprises a watchdog circuit, a power monitoring and resetting circuit and a logic enabling circuit, wherein the logic enabling circuit is connected with the output end of the watchdog circuit and the output end of the power monitoring and resetting circuit. When the power monitoring and resetting circuit outputs effective power signals and the watchdog circuit outputs resetting signals, resetting signals of the microprocessor are output. Resetting false operation generated in the power-on and power-off processes of an external power source are avoided. Resetting false operation caused by delayed resetting when a general watchdog circuit is used after the power is connected can be avoided. The power monitoring and resetting circuit is connected with the microprocessor and provides effective signals, synchronous with the watchdog circuit, of the external power source, real-time monitoring of the state of the external power source and synchronizing of the watchdog circuit can be achieved by the microprocessor, and false operation due to the fact that the microprocessor can not forecast the state of the watchdog circuit can be avoided. Based on the synchronous signals, active peripheral circuit management is achieved, and the power consumption is reduced.

The invention discloses an adjustable pulse generator which comprises a waveform generation circuit, a waveform delay circuit and a waveform processing circuit. After the waveform generation circuit is powered on, rectangular waves with the adjustable duty ratio and period are periodically generated. The waveform delay circuit delays the rectangular wave for a first time and outputs the delayed rectangular wave as a first output signal, and delays the rectangular wave for a second time and outputs the delayed rectangular wave as a second output signal, wherein the second time is greater than the first time, and the time difference between the two times is adjustable; and the waveform processing circuit performs waveform processing based on the first output signal and the second output signal to obtain a pulse signal with adjustable pulse width, pulse value and pulse period. Visibly, the pulse width, the pulse value and the pulse period of the pulse signal provided by the adjustable pulse generator are adjustable, so that the pulse signal can well simulate the noise signal to be input into the line to test the filtering capability of the line, and the reference value of the line filtering capability test is improved.

The invention discloses a single-photon avalanche photodiode calibration system, relates to the field of quantum communication, and solves the problem of how to accurately and automatically test SPADkey parameters. The system comprises an upper computer, an SPAD calibration system control panel, a picosecond pulse laser, a variable optical attenuator, an SPAD mounting plate and a temperature box;the SPAD calibration system control panel is connected with the picosecond pulse laser; the picosecond pulse laser is connected with the variable optical attenuator; the variable optical attenuator is connected to an SPAD to be tested through an optical fiber, and the mounting plate is provided with a gating signal interface, a bias signal interface and an avalanche signal interface. The SPAD tobe tested is mounted on the mounting plate; the mounting plate is mounted in the temperature box; the calibration system control panel is connected with the upper computer; the invention further provides a single-photon avalanche photodiode calibration method. The system has the advantages that multiple performance parameters of the SPAD to be tested can be tested in a short time, and the system is efficient, convenient, easy to operate and easy to learn.