Abstract: A method for manufacturing a large-area volume grating includes: (1) splitting a laser beam into two or more laser beams, converging the two or more laser beams into a sample at an angle less than 60° to form a first plasma grating; (2) moving the sample in a longitudinal direction of a plane vertical to the first plasma grating to etch out a first prefabricated volume grating; (3) moving the sample laterally to form a second plasma grating, an effective cross section of the first prefabricated volume grating partially overlapping with that of the second plasma grating, then moving the sample in a longitudinal direction of a plane vertical to the second plasma grating to etch out a second prefabricated volume; and (4) repeating steps (2) and (3) n times to obtain a volume grating in any size.

Abstract: A method for producing a conductive glass fiber mesh with laser induced coating graphene comprises: (I) preparing a glass fiber paper coated with a carbon-containing precursor material; (II) subjecting the glass fiber paper coated with the carbon-containing precursor material to laser irradiation to reduce the carbon-containing precursor material into the laser induced coating graphene, obtaining a glass fiber paper coated with the laser induced coating graphene; and (III) folding the glass fiber paper coated with the laser induced coating graphene to obtain the conductive glass fiber mesh with laser induced coating graphene.

Abstract: A Raman spectrometric imaging method, including: placing a sample on a two-dimensional translation stage; emitting a first light beam by a first optical comb light source; dividing the first light beam into a pump light beam and a depletion light beam to illuminate the sample; guiding the pump light beam to illuminate a region of the sample to excite molecules of the sample in the region; guiding the depletion light beam to the region of the sample to make excited molecules at a periphery of the region to return into a vibrational ground state; emitting a second light beam as a probe light beam by a second optical comb light source to the remaining excited molecules to generate a CARS signal; recording the CARS signal for imaging; moving the two-dimensional translation stage to scan other regions of the sample to form an image of the sample.

Abstract: Provided is a method for preparing a graphene-copper calcium titanate CCTO based ceramic composite dielectric material, which includes: dissolving metal ion sources in respective solvents to obtain respective solutions, and mixing the solutions evenly to obtain a precursor collosol of the CCTO based ceramic; allowing the precursor collosol of the CCTO based ceramic to stand for aging, followed by adding a graphene oxide dispersion to mix with the precursor collosol evenly, drying the resulting mixture to obtain dry precursor powders of the graphene-CCTO based ceramic, which are then grinded into fine powders, followed by irradiating by a low-power laser to obtain graphene-CCTO based ceramic composite powders; and compacting and molding the graphene-CCTO based ceramic composite powders, followed by catalytic synthesis with a high-power laser to obtain the graphene-CCTO based ceramic composite dielectric material.

Abstract: A method and a system for controlling an optical frequency comb, where the working power of the pump source is dynamically adjusted and controlled, which not only greatly shortens a control time of a stable mode-locking and realizes a fast mode-locking control, but also quickly stabilizes the power control of stable working condition, thereby reducing unnecessary power consumption caused by power reciprocating oscillation tracking controls and better achieving the energy-saving effect of the power adjustment control process. The temperature of the working environment of the pump source is dynamically adjusted and controlled, so that the environment temperature can quickly reach the reference environment temperature required for mode-locking, which not only creates a good temperature condition for the mode-locking of the optical comb system, but also improves the efficiency of environment temperature stability control in the stable working conditions.

Abstract: Disclosed is a method for preparing a carbon-reinforced metal-ceramic composite material, including: mixing raw materials of carbon, copper, zinc, titanium, copper oxide, calcium oxide and titanium dioxide, ball-milling the raw materials with a medium of ethanol to obtain a mixture, drying and milling the mixture to obtain a powder, sintering the powder with a laser having an irradiation power ranging from 100 to 600 W and an irradiation period of 3 min to 10 min to obtain a product, and rapidly cooling the product to allow a temperature of the product to be decreased to the room temperature within 5 min to obtain the carbon-reinforced metal-ceramic composite material.

Abstract: The present disclosure discloses a method and apparatus for manufacturing a microfluidic chip with a femtosecond plasma grating. The method is characterized in that two or more beams of femtosecond pulse laser act on quartz glass together at a certain included angle and converge in the quartz glass, and when pulses achieve synchronization in time domain, the two optical pulses interfere; Benefited by constraint of an interference field, only one optical filament is formed in one interference period; and numbers of optical filaments are arranged equidistantly in space to form the plasma grating. The apparatus for manufacturing the microfluidic chip includes a plasma grating optical path, a microchannel processing platform, and a hydrofluoric acid ultrasonic cell.

Abstract: The present disclosure discloses a method and apparatus for preparing a femtosecond optical filament interference direct writing volume grating/chirped volume grating. The method is characterized in that optical filaments are formed in glass by using femtosecond pulse laser, and plasma is controlled to quickly scan in the glass and etch a volume grating or chirped volume grating structure by adjusting the focal length of convex lens, laser energy and movement of motor machine. The apparatus includes a femtosecond pulse laser module, a pulse chirp management module, a pulse time domain shaping module, a laser separation and interference module, a glass volume grating processing platform module and a camera online imaging module.

Abstract: Provided are a method and a system for measuring a transient time width of an ultrashort pulse in real time. The method includes: performing an interaction of a laser pulse to be measured with a linear chirped pulse in a second-order non-linear medium, to generate a sum-frequency beam, wherein an intensity sag occurs in the chirped pulse after the interaction; performing a time spreading by a time stretching system on the chirped pulse with the intensity sag; detecting the spread chirped pulse with the spread intensity sag by a photoelectric detector, and measuring and recording a time width ?? of the spread intensity sag by an oscilloscope; and obtaining the transient time width ? of the laser pulse to be measured according to a formula of ?=??/M, where M is an amplification coefficient of the time stretching system.

Abstract: A device and a method for direct printing of a microfluidic chip based on a large-format array femtosecond laser. The large-format array femtosecond laser with multi-parameter adjustable laser beam state is used to achieve large-format laser interference. The interference state, interference combination and exposure mode of the large-format array femtosecond laser are regulated, and multiple exposures are superimposed to output the desired pattern for the microfluidic chip, enabling the direct printing processing of the microfluidic chip.

Abstract: A silicon nitride phased array chip based on a suspended waveguide structure, which includes a silicon nitride waveguide area and a suspended waveguide area. The silicon nitride waveguide area includes a silicon substrate, a silicon dioxide buffer layer, a silicon dioxide cladding layer and a silicon nitride waveguide-based core layer. The silicon nitride waveguide-based core layer includes an optical splitter unit, a first curved waveguide, a thermo-optic phase shifter and a spot-size converter. The suspended waveguide area includes a second curved waveguide and an array grating antenna.

Abstract: A method for processing a micro-channel of a micro-fluidic chip using multi-focus ultrafast laser, in which an array-type multi-focus femtosecond laser is used to perform fractional ablation on the micro-fluidic chip, and then pulse laser is used to perform secondary ablation on the micro-fluidic chip. Ultrasonic-assisted hydrofluoric acid etching is performed on the micro-fluidic chip after ablation to obtain a true three-dimensional micro-channel on the micro-fluidic chip. A device for processing a micro-channel of a micro-fluidic chip using multi-focus ultrafast laser is also provided.

Abstract: A method and a system for automatically controlling mode-locking of an optical frequency comb, where the stored control parameters of the working condition in the mode-locked state is combined with the collected working feedback parameters of the optical frequency comb system to dynamically adjust and control the working power of the pump source or/and the temperature of the working environment of the pump source, which not only greatly shortens the control time for stable mode-locking and realizes a fast mode-locking control, but also reduces unnecessary power consumption, thereby further guaranteeing the energy-saving effect of power adjustment control process. The present disclosure well maintains the stable working conditions of the optical comb system, and realizes the mode-locking optimization control of an update mode for the big data, thereby effectively improving the mode-locking control process of the optical frequency comb system, and providing higher operation stability and measurement accuracy.

Abstract: A method and a system for controlling an optical frequency comb, where the working power of the pump source is dynamically adjusted and controlled, which not only greatly shortens a control time of a stable mode-locking and realizes a fast mode-locking control, but also quickly stabilizes the power control of stable working condition, thereby reducing unnecessary power consumption caused by power reciprocating oscillation tracking controls and better achieving the energy-saving effect of the power adjustment control process. The temperature of the working environment of the pump source is dynamically adjusted and controlled, so that the environment temperature can quickly reach the reference environment temperature required for mode-locking, which not only creates a good temperature condition for the mode-locking of the optical comb system, but also improves the efficiency of environment temperature stability control in the stable working conditions.

Abstract: Provided is a system for measuring gas temperature and component concentrations in a combustion field based on optical comb. The system includes two pulse laser devices, two continuous laser devices, a beam splitting device, a measurement path, an interference signal detecting device, an optical processing and electrical processing device and a signal acquisition and analysis device. The measurement path refers to the combustion field to be measured. The interference signal detecting device outputs an interference signal. The optical processing and electrical processing device includes several optic elements and electrical elements, and outputs an adaptive compensation signal and an asynchronous sampling clock signal after a series of processing on output of the two pulse laser devices and two continuous laser devices. The signal acquisition and analysis device outputs the measurement result based on the adaptive compensation signal, the asynchronous sampling clock signal and a stable interference signal.

Abstract: The disclosure provides a super-resolution fast-scanning coherent Raman scattering imaging method. The method: using pump light and Stokes light; combining the pump light and the Stokes light to obtain combined light; expanding/collimating the combined light; the combined light after the expanding/collimating entering a galvanometer, passing through a group of a scanning lens/a tube lens and being focused on a back focal plane of a microobjective and incidenting into a biological sample, such that the biological sample is excited to emit anti-Stokes light; collecting the excited anti-Stokes light by a detector. This method is characterized by deflecting, at different angles, a single light spot focused on the microobjective through a diffractive optics group including DOE and a dispersive element, into a plurality of 1×N light spots to incident into the biological sample, such that the anti-Stokes light excited from smaller molecules and being condensed and filtered, is collected by the detector.

Abstract: The present disclosure relates to a gain optical fiber heat-dissipating device for high power ultra-fast laser, including a gain optical fiber and a heat-dissipating structure. The heat-dissipating structure includes a metal tube, a flexible heat-conducting layer and a water-cooling structure. The gain optical fiber is passed through the metal tube, and the flexible heat-conducting layer is provided between the metal tube and the gain optical fiber. The water-cooling structure is provided on the metal tube to reduce temperature of the gain optical fiber. The gain optical fiber heat-dissipating device according to the present disclosure can dissipate the heat through a water-cooling mode, and realize rapid heat dissipation, thus improving heat-dissipating efficiency.

Abstract: Provided are a time and frequency control method and system for optical comb. The method includes: controlling an optical comb measuring system to start and to generate an optical comb; obtaining monitoring data, wherein the monitoring data comprises a working temperature, a mode-locked frequency and a light pump power, wherein the mode-locked frequency comprises a repetition frequency and a carrier envelope phase locked at the end of starting the optical comb measuring system; determining whether an offset of the mode-locked frequency exceeds a self-feedback adjustment range of a hardware adjustment circuit; and in response to any of the repetition frequency and the carrier envelope phase exceeds the self-feedback adjustment range, adjusting the working temperature and the light pump power until the mode-locked frequency returns back into the self-feedback adjustment range.

Abstract: A three-port silicon beam splitter chip includes an input waveguide, three output waveguides, and a coupling region disposed between the input waveguide and the output waveguides and being in a square shape. The input waveguide and the output waveguide have a same width K, where 490 nm<K<510 nm, the coupling region, the input waveguide and the output waveguide have a same thickness H, where 210 nm<H<230 nm, and the coupling region has a length L, where 1600 nm<L<2000 nm. The three-port silicon beam splitter chip of the present disclosure has a high integration degree and a small size, and is capable of improving the portability of the wavefront reconstruction device.

Abstract: The disclosure provides a super-resolution fast-scanning coherent Raman scattering imaging method. The method: using pump light and Stokes light; combining the pump light and the Stokes light to obtain combined light; expanding/collimating the combined light; the combined light after the expanding/collimating entering a galvanometer, passing through a group of a scanning lens/a tube lens and being focused on a back focal plane of a microobjective and incidenting into a biological sample, such that the biological sample is excited to emit anti-Stokes light; collecting the excited anti-Stokes light by a detector. This method is characterized by deflecting, at different angles, a single light spot focused on the microobjective through a diffractive optics group including DOE and a dispersive element, into a plurality of 1xN light spots to incident into the biological sample, such that the anti-Stokes light excited from smaller molecules and being condensed and filtered, is collected by the detector.