69 results about "Pulse broadening" patented technology

This application discloses an assembly and adjustment device for a pulse broadening unit, comprising: a visible light source device, a pulse broadening unit, a phase delay element, a linear polarizer, and a reticle; the pulse broadening unit includes a beam splitter and a mirror assembly; the output beam from the visible light source device is incident on the beam splitter; the beam splitter splits the received output beam into a first reflected beam and a transmitted beam; the first reflected beam, after passing through a reflective lens assembly, is incident on the exit surface of the beam splitter, and after being reflected by the exit surface, it illuminates the reticle together with the transmitted beam; the linear polarizer is disposed in the optical path from which the transmitted beam exits, and the angle between its transmission direction and the polarization direction of the transmitted beam transmitted from the beam splitter satisfies the following condition: eliminating part of the energy of the transmitted beam; the phase delay element is disposed in the optical path before the first reflected beam is incident on the exit surface of the beam splitter, and is used to rotate the polarization direction of the first reflected beam by the same angle.

A laser device includes an oscillator outputting pulse laser light; an amplifier amplifying the pulse laser light; an optical pulse stretcher extending a pulse width of the pulse laser light; a beam divergence angle adjuster including an upstream lens arranged on an optical path of the pulse laser light, a downstream lens arranged downstream of the upstream lens, and an optical path length changing mechanism for changing an inter-lens optical path length between the upstream lens and the downstream lens; and a processor controlling the beam divergence angle adjuster and obtaining a repetition frequency or a duty of the pulse laser light, and to change, when the repetition frequency or the duty changes by a preset threshold or more, the inter-lens optical path length so that the beam divergence angle of the extended pulse laser light becomes small in accordance with the repetition frequency or the duty after the change.

The application discloses a kind of photonic auxiliary microwave signal time-frequency amplitude phase measurement system and method, pulse light source output light pulse in the system enters input end dispersion medium and completes pulse broadening, then enters electro-optic modulation module, simultaneously power divider receives microwave signal and it is divided two-way input electro-optic modulation module in upper and lower sub-modulator to modulate light pulse;The modulated light signal output by the electro-optic modulation module passes through output end dispersion medium, completes time convolution process, after this, output light signal will pass through optical coupling module and be divided into two paths, in turn pass through polarization controller, polarization beam splitter, photodetector, analog-digital converter, digital signal processor, the position information and amplitude information of electric pulse are collected, and the time, amplitude, frequency and phase information of microwave signal are obtained.The application can simultaneously measure the time, frequency, amplitude, phase information of microwave signal, and does not need complex post-processing, and processing speed is fast.

The application discloses a time-to-digital converter based on pulse stretching. The time-to-digital converter structure combines frequency multiplication delay locked loop, pulse stretching circuit and calibration circuit, guarantees high resolution, effectively increases the range of the time-to-digital converter, and can reduce the influence of PVT. The calibration circuit has simple structure, low calibration cost, and is suitable for the calibration of the pulse stretching circuit. In addition, the calibration algorithm for the static phase error of the frequency multiplication delay locked loop only needs to increase a 1bit counter, the additional circuit cost is very small, and the influence of the static phase error of the frequency multiplication delay locked loop can be overcome.

The invention relates to the technical field of microscopic imaging, and particularly provides a stimulated Raman scattering microscopic imaging system capable of simultaneously scanning double Raman frequency shift spectrums, which comprises a laser light source driving and modulating unit and a signal detecting and data processing unit, the laser light source driving and modulating unit comprises a dual-channel laser synchronous excitation module, a light beam polarization regulation and power distribution module, a pulse broadening and spectrum focusing module, a dual-channel dual-phase modulation module, a common-path different-time dual-frequency difference module and a laser scanning and telecentric focusing module; and the signal detection and data processing unit comprises a dual-channel orthogonal demodulation module and a scanning driving and signal synchronous acquisition module. Compared with the prior art, the dual-Raman frequency shift spectrum scanning stimulated Raman microimaging device has the advantages that dual-Raman frequency shift spectrum scanning stimulated Raman microimaging with higher acquisition speed, high resolution and wide spectrum coverage range is realized, and the problem of long time consumption for acquiring the complete spectrum of the to-be-tested sample by the traditional single-frequency resonance spectrum scanning stimulated Raman microimaging is solved.

This laser device is provided with: a laser oscillator which includes an optical resonator and a pair of electrodes for generating discharge by applying a voltage to a laser gas, and which outputs a first pulsed laser light; a first optical pulse stretcher that transmits a portion of the first pulse laser light, surrounds the other portion of the first pulse laser light by one circle, and outputs a first transmitted light and a first one-circle surrounding light, which have a first shift amount and spatially overlap a portion of the first transmitted light and the first one-circle surrounding light, thereby outputting a second pulse laser light in which the pulse time width of the first pulse laser light has been expanded; and a second optical pulse stretcher that transmits a part of the second pulse laser light, surrounds the other part of the second pulse laser light by one circle, and outputs second transmitted light and second one-circle surrounding light that have a second offset amount different from the first offset amount and spatially overlap a part of the second transmitted light and a part of the second one-circle surrounding light. As a result, a third pulse laser beam having an extended pulse time width of the second pulse laser beam is output.

Apparatus for and method of aligning optical components such as beam splitters in an optical pulse stretcher in which a landing spot of a beam which has traversed a portion of the optical beam splitter and a coincident landing spot of a beam split from a retroreflected input beam are made to align on a target spot. Also disclosed is an apparatus and method for aligning the retroreflector to facilitate proper beam alignment. A fluorescent material may be used to render a beam landing spot visible.

The application relates to an underwater laser pulse time domain expansion measurement system and method, wherein the measurement system comprises a receiving lens for directly aiming at a pulse laser to be measured and receiving a laser beam output by the pulse laser to be measured; a laser processing unit connected with the receiving lens in an optical path to perform collimation, attenuation and light filtering processing on the laser beam; a high-speed photoelectric detector connected with the laser processing unit in an optical path, used for collecting the processed laser beam and converting the laser pulse electrical signal W1; a data acquisition board electrically connected with the high-speed photoelectric detector, used for collecting the laser pulse electrical signal W1 and sending the laser pulse electrical signal W1 to an analysis processing unit; and the analysis processing unit receives the laser pulse electrical signal W1, calculates the pulse width of the laser pulse electrical signal W1, and calculates the time domain expansion of the laser beam according to a pulse expansion calculation method. The application realizes direct measurement of the time domain expansion of an underwater laser pulse, and improves the measurement accuracy.

The invention provides a femtosecond laser pulse compression system with a compact structure and an adjustable pulse width, and relates to the technical field of femtosecond lasers, the system sequentially comprises a seed source, a pulse stretcher, an amplification chain and a pulse compression device along a light path, the pulse compression device comprises a polarization beam splitting unit, an electro-optical polarization modulation unit, a single compression grating and a light path turn-back unit; wherein the polarization beam splitting unit, the electro-optical polarization modulation unit, the single compression grating and the light path turn-back unit jointly form a multi-channel folding compression light path; a voltage signal with a specific time sequence is applied to the electro-optical polarization modulation unit, and the polarization state of a light beam is dynamically switched, so that the light beam is selectively controlled to complete back-and-forth transmission of a preset number of times in a multi-channel folding compression light path in different polarization states, and the compression ratio of laser pulses and the width of output pulses are continuously adjusted. On the premise that large-spread-width matching is guaranteed, the system is extremely compact, and the pulse width is continuously and flexibly adjusted in an electric control mode.

The application provides a method and device for intra-channel and inter-channel nonlinear joint compensation of a WDM system based on an improved LDBP and electronic equipment, and belongs to the technical field of optical fiber communication. The method compensates dispersion by using a linear filter in the time domain, the corresponding network structure is designed as one-dimensional convolution, and the pulse broadening effect is combined in the overlap reservation method, the physical model of nonlinear compensation is improved by considering the interference of intra-channel dispersion pulse broadening and the walk-off effect between channels, and the purpose of intra-channel and inter-channel nonlinear joint compensation is achieved. The application fully utilizes the random interaction between inherent dispersion and nonlinearity in the optical fiber communication system to compensate the phase shift caused by the nonlinear effect, can effectively equalize the nonlinear distortion of the signal under the condition of controlling the calculation complexity and reducing the implementation cost, and is expected to play a better role in the long-distance transmission of the large-capacity WDM system.

A pulse stretcher includes a beam splitter splitting pulse laser light into two beams of pulse laser light, first concave mirrors arranged side by side in a predetermined direction, and second concave mirrors arranged side by side in the predetermined direction as having the same number as the first concave mirrors and facing the first concave mirrors, respectively. One beam of pulse laser light split by the beam splitter travels to one first concave mirror among the first concave mirrors and is reflected alternately by the first concave mirrors and the second concave mirrors 12 times or more as even number times to return to the beam splitter. A number of overlapping of the one beam at each of concentration points where at least part of the one beam of pulse laser light overlaps at beam waists of the one beam is two.

An optical pulse stretcher for stretching the pulse width of pulsed laser light, the optical pulse stretcher comprising: a polarizer that separates a component of incident pulsed laser light that has a specific polarization direction; delay optics including a plurality of mirrors for propagating the pulsed laser light that has been reflected by or transmitted through the polarizer; and a first Faraday rotator that includes a first magnet and a first Faraday material, is disposed on the optical path of the delay optics, and rotates the polarization direction of the pulsed laser light.

This invention discloses a device for real-time analysis of multidimensional information of spatiotemporally mode-locked pulses using an all-fiber structure, belonging to the field of ultrafast optics technology. It includes an all-fiber spatiotemporally mode-locked laser platform, a raw pulse beam profile measurement module, an optical circulator, a sub-pulse beam profile measurement module, and a dispersive Fourier transform and real-time spectral information detection module. Based on the generalized multimode nonlinear Schrödinger equation, this invention constructs a theoretical model of the spatiotemporally mode-locked laser, explores the multidimensional parameter coupling mechanism during spatiotemporal mode-locking, clarifies the mapping relationship between modes and frequencies, and provides a theoretical basis and method for high-precision mode differentiation and multidimensional real-time information extraction. This invention aims to rationally design the parameters of each fiber grating according to the spectral width and temporal interval of the spatiotemporally mode-locked pulse, reflecting more sub-pulses while ensuring that the pulse temporal domains do not overlap, achieving high-precision spatial mode resolution, and maximizing pulse broadening to obtain high-resolution real-time spectral information.

A laser apparatus includes an oscillator configured to output a pulse laser beam, a random phase plate disposed in an optical path of the pulse laser beam, and an optical pulse stretcher disposed in the optical path of the pulse laser beam that has passed through the random phase plate and configured to stretch a pulse time width of the pulse laser beam by transmitting part of the pulse laser beam, making the other part circulate at least once through a delay optical path, and outputting transmitted light and circulating light.

The invention discloses a preparation method of a small pulse broadening drift tube for ultrafast diagnosis and the pulse broadening drift tube thereof. The method comprises the following steps: 1) brazing a front shell and a rear shell, and carrying out indium filling, indium melting and indium turning operation on the front shell; 2) performing spot welding to obtain a first grid mesh assembly, a second grid mesh assembly and a third grid mesh assembly; 3) preparing a substrate, a conductive film layer and a sealing film layer, and assembling to obtain a cathode input window; (4) sealing the metal anode flange, the frit ring and the optical fiber panel at high temperature, and plating a metal layer on the small surface of the optical fiber panel to prepare an anode assembly; (5) the first grid mesh assembly and the second grid mesh assembly are assembled on the front shell to obtain the front shell provided with the front assembly; and 6) preparing a cathode input window and a cathode at the rear end, degassing at high temperature, electronically brushing and sealing indium at high vacuum degree to obtain the small pulse broadening drift tube which can meet the requirements of the technical fields of nuclear detection, high-energy physics and the like on ultrafast diagnosis equipment.

A mid-infrared laser generation system based on dispersion-managed soliton bunch pulses. The system can achieve high-power, high-efficiency and high-proportion mid-infrared laser output, and has the advantages of an all-fiber configuration, a compact structure and a high power proportion in a longer-wavelength region of a mid-infrared spectrum. A pulsed fiber laser device generates a nanosecond pulse laser in a 1.5-micron band. A fiber pulse stretcher is made of a single-mode silica fiber, splits nanosecond pulses into a plurality of ultrafast soliton pulses by means of a nonlinear effect, and performs spectral energy conversion from 1.5 microns to 2.4 microns. A fiber laser amplifier further increases the output power of a stretched pulse laser and extends a spectrum to a 2.7-micron band, and also increases pulse energy beyond a 2.3-micron band. A fiber mode field adapter efficiently couples into a nonlinear fiber pulses generated in the fiber laser amplifier. The nonlinear fiber extends a laser to a mid-infrared 3-5-micron band, thereby achieving high-power, high-efficiency and high-proportion mid-infrared laser output.

The application discloses a LOS state detection circuit for an SFP optical module, which comprises an input inversion module, a signal conditioning and pulse expansion module and a threshold comparison and decision module connected in sequence. The input inversion module comprises a receiving original port link state indication signal, which is used for logical inversion of the original signal and enhancement of driving capacity. The signal conditioning module converts the data pulse stream output by a PHY chip into a smooth direct current voltage by using peak holding and RC expansion technology. The threshold comparison module intelligently judges whether the voltage represents valid signal activity through a hysteresis comparator, and finally outputs a hardware LOS signal which strictly conforms to the SFP MSA standard and is highly stable. The application realizes reliable optical signal loss detection in a full hardware mode, solves the problems of unstable output and easy misjudgment of a traditional scheme, and has the advantages of low cost, small area, fast response and high reliability, and is particularly suitable for integrated SFP optical module design.

The application belongs to the field of laser emitting devices, and provides a system and method for compensating high-order dispersion through cooperative adjustment of stretching and compression, calculating second-order dispersion and third-order dispersion introduced by a pulse amplifier; adjusting the introduced third-order dispersion by changing the grating incident angle in a pulse stretcher, so that the third-order dispersion is offset with the total third-order dispersion of the system; calculating the second-order dispersion value required to be provided by the pulse compressor according to the second-order dispersion change generated after the angle adjustment of the pulse stretcher, and accurately compensating by adjusting the effective distance of the grating pair; feeding back the third-order dispersion of the pulse compressor after adjustment to correct the angle of the pulse stretcher again, and repeating the above steps until the total second-order dispersion and third-order dispersion of the system tend to be zero, so as to realize near transform limit compression. The application adjusts the grating incident angle of the stretcher and the effective distance of the grating of the compressor, so that the second-order dispersion and third-order dispersion in the ultrafast laser system are simultaneously compensated, and near transform limit pulse output is obtained.

The present application provides a kind of wideband pulse light source device with excellent performance, which solves the problem of SC light with seed light wavelength region remaining at high intensity. The light from the pulse laser source (1) is made to generate nonlinear effect by the nonlinear element (2) to generate supercontinuum light, and the light of the oscillation wavelength of the residual pulse laser source (1) is attenuated when being split by the dichroic mirror (32). The split light is pulse stretched by the optical fiber (41), and is multiplexed by the multiplexing element (33) to irradiate the object (S). The light transmitted through the object (S) is received by the light receiver (6), and the output signal thereof is converted into a spectrum by the operation unit (7).

This invention discloses a multi-stage cascaded laser frequency doubling device, belonging to the field of laser frequency doubling technology. It includes a front-end frequency doubling module and at least one cascaded frequency doubling module arranged sequentially along the optical path. The cascaded frequency doubling module includes a second-harmonic crystal, a third-harmonic crystal, a beam splitter, a delay adjustment device, and a beam combiner. The front-end frequency doubling module, beam splitter, second-harmonic crystal, beam combiner, and third-harmonic crystal are connected sequentially. By extending the multi-stage continuous cascaded crystal architecture, the long crystal is split into a sequence of thin frequency doubling crystals, suppressing time drift and pulse broadening. Each stage is equipped with a multi-band fully transparent film system to reduce dispersion. Furthermore, a beam splitting and beam combining bypass and dynamic time delay compensation are designed to achieve precise spatiotemporal beam combining of ultraviolet light, enabling femtosecond lasers to possess both high efficiency, low broadening, and excellent pulse quality.

The invention relates to the technical field of optical fiber communication, and provides a submarine network communication time service synchronization method and system, and the method comprises the steps: obtaining a first pulse broadening of a source end, and a second pulse broadening of a sink end; according to the first pulse broadening and the second pulse broadening, calculating a one-way optical fiber receiving length between wave combining and wave splitting to obtain a first optical fiber length and a second optical fiber length; and obtaining a time compensation value according to the first optical fiber length and the second optical fiber length. Through obtaining pulse broadening data of a source end and a sink end, the actual length of a unidirectional transmit-receive optical fiber between a combined wave and a split wave is reversely calculated, and a precise time compensation value is calculated by using the length of a first optical fiber and the length of a second optical fiber. Time deviation caused by link physical structure difference can be effectively counteracted by compensating time of a core error of'unequal lengths of transmitting and receiving optical fibers', the problem of error accumulation in a traditional time service technology is solved, the precision of submarine network time service is greatly improved, and the high-precision requirement of underwater observation and monitoring equipment for data time relevance is met.

The application discloses a chirp pulse stretching and compressing device and an amplification system, and relates to the field of lasers. The chirp pulse stretching and compressing device comprises a first polarization beam splitter prism, a pulse stretching and compressing device and a dispersion regulator. The chirp pulse stretching and compressing device has a stretching port and a compressing port arranged oppositely, is divided into a stretching light path part and a compressing light path part, the two light path parts share one main stretching and compressing module, and the stretching light path part is additionally provided with a dispersion regulator to provide adjustable and additional dispersion compensation. The chirp pulse stretching and compressing device provided by the application can be flexibly adapted to different amplification systems, so that the output light pulse reaches near-zero chirp and ultra-short pulse width is realized.

The application discloses a kind of ultra-short pulse width multi-path broadening system and method, it is related to high-power ultra-short pulse amplification field.The multi-path broadening system includes at least one body bragg grating and polarization reflection unit;The multi-path broadening system utilizes optical path design to make pulse laser multiple times through body bragg grating, realizes the multi-path body bragg grating pulse broadening of pulse laser in system by adjusting the polarization state of light beam.Compared with prior art, the application utilizes optical path design to make pulse laser multiple times vertically through body bragg grating, realizes the multi-path body bragg grating pulse broadening of pulse laser in system by adjusting the polarization state of light beam, so as to realize the great broadening of pulse width to nanosecond above, greatly reduce the complexity of system without the help of additional devices such as optical fiber, increase the stability of system, and realize high-power laser output.

The present application provides a laser device and a manufacturing method of an electronic device, the laser device according to one aspect includes: a discharge excitation type laser oscillator which outputs pulsed laser in an ultraviolet wavelength region; a first optical pulse stretcher which includes a beam splitter and a plurality of concave mirrors, and which expands a pulse width of the pulsed laser; and a relay lens which includes a first lens and a second lens arranged on an optical path of the pulsed laser after the pulse width is expanded, the first lens being a spherical plano-convex lens, and the second lens having a focal length in a long side direction of a beam cross section of the pulsed laser which is shorter than a focal length in a short side direction.

A laser apparatus according to an aspect of the present disclosure includes a laser oscillator configured to emit a pulse laser beam, and a first optical pulse stretcher, a second optical pulse stretcher, and a third optical pulse stretcher that are disposed on an optical path of the pulse laser beam. When L1 represents an optical path length of a delay optical path of the first optical pulse stretcher, L2 represents an optical path length of a delay optical path of the second optical pulse stretcher, L3 represents an optical path length of a delay optical path of the third optical pulse stretcher, and n represents an integer equal to or larger than two, L2 is an integral multiple of L1 by an integer equal to or larger than two and L3 satisfies the following condition: (n−0.75)×L1≤L3≤(n−0.25)×L1.

The application provides an optimization method of a grating monochromator, including obtaining a boundary wavelength satisfying a preset parameter limit condition, and determining a grating parameter ternary diagram corresponding to the boundary wavelength; in the grating parameter ternary diagram, determining a target grating line density and a to-be-corrected focal constant corresponding to a convex grating monochromator; adjusting a grating curvature radius and a variable-line-spacing parameter of the convex grating monochromator and correcting the to-be-corrected focal constant according to the preset parameter limit condition, to obtain a target variable-line-spacing parameter, a target grating curvature radius and a target focal constant; and determining grating parameters corresponding to each light wavelength in the convex grating monochromator according to the target variable-line-spacing parameter, the target grating line density, the target grating curvature radius and the target focal constant, wherein the grating parameters include one or more of a spot size, an energy resolution, a pulse broadening, a grazing incidence angle and a grating blaze angle. The application solves the technical problem of a narrow wavelength range of the grating monochromator applied to an X-ray waveband.

This invention discloses a detection system and method for cable fault location, relating to the field of cable fault location technology. It acquires nanosecond-level pulse propagation front-end change trajectory data and echo peak width change data to establish a high-frequency attenuation continuous-time distribution map; extracts pulse broadening growth segments and performs front-end compression control to form a compressed pulse front-end shape; rearranges the peak time position to separate low-amplitude reflection signals; tracks its amplitude trajectory and identifies local insulation anomaly segments by comparing with the peak width evolution trajectory; establishes a distance-back mapping and corrects the echo time coordinates to obtain the fault location interval. This invention improves the ability to identify early insulation defects by constructing a continuous-time distribution map and compressing pulse broadening segments, shortening the peak diffusion time, and separating low-amplitude reflection signals within the peak; simultaneously, it improves fault location accuracy and stability by establishing a distance-back mapping relationship and dynamically correcting the echo time coordinates.

The invention discloses a linear multi-path optical pulse broadening system which comprises a pulse broadening module and a turn-back module, the pulse broadening module is used for broadening pulses, and the turn-back module is arranged at the incident end of the pulse broadening module along an optical path so that the broadened pulses can be reflected into the pulse broadening module again. According to the system, the laser pulse can linearly reciprocate for multiple times in the broadening device according to preset times, so that multi-pass broadening is realized, and the system is compact in overall structure and easy to debug.

The utility model provides a kind of ultrasonic sensor, second matching layer is integrated with piezoelectric ceramic in the accommodating space of first matching layer, form integrated packaging structure, i. e. first matching layer is used as the shell of ultrasonic sensor, also as matching layer, eliminate the acoustic wave reflection interface between the shell of traditional ultrasonic sensor and matching layer, make sound energy transmission efficiency significantly improve;At the same time, the inner wall of accommodating space and second matching layer directly abut, reduce the acoustic impedance mismatch problem between multilayer medium, reduce liquid-sensor interface echo loss, improve the signal-to-noise ratio of flow detection signal;Use 0-3 type composite piezoelectric ceramic, the composite structure of its polymer matrix and piezoelectric ceramic particle can widen sensor operating bandwidth, have lower QM value and faster response rate, eliminate the pulse broadening problem caused by the QM value of traditional PZT piezoelectric ceramic in liquid medium is too high, further improve detection precision.

This invention relates to the field of optical detection technology, specifically providing a coherent anti-Stokes Raman scattering imaging method and apparatus, comprising: splitting an initial light emitted from a driving light source into a driving light and a Stokes beam; processing the driving light into a signal light based on an optical parametric amplifier; performing pulse broadening processing on the signal light in a first optical path, or performing pulse broadening processing on the Stokes beam in a second optical path; combining the signal light and the Stokes beam into a third optical path, and performing pulse broadening processing on the signal light and the Stokes beam in the third optical path to obtain chirped signal light and Stokes beam; and performing coherent anti-Stokes Raman scattering imaging on a target sample based on the chirped signal light and the Stokes beam. This addresses the problem that related technologies cannot simultaneously achieve high-quality and fast hyperspectral imaging.