76 results about "Picosecond pulsed laser" patented technology

A device and a method for ultrafast picosecond pulse laser machining of a super-hydrophobicity micro-structure surface belong to the field of preparation of functional micro-structure surfaces, and aim to solve the problems of high investment and low output of an existing machining process and existing machining technology for functional elements. The device comprises an ultrafast picosecond pulse laser source, an optical isolator, five reflectors, a rotary liquid crystal polarizing film, a polarization beam splitter, two beam collectors, a half wave plate, a focusing lens, frequency-doubling generator LBO (lithium triborate) crystal, a dichroic mirror, a light control device, a beam profile curvometer, a beam amplifying component Kepler beam expander, a focusing machining lens, a machining platform, a microscopy imaging CCD (charge coupled device) component and a control system. The method includes the stepsof: fixing a steel workpiece onto a surface driven by a Z-directional guide rail of the machining platform; adjusting a light path; detecting the surface of the workpiece by a probe; and driving the workpiece to move by means of movement of an X-directional guide rail and a Y-directional guide rail of the machining platform. The device and the method are used for preparing the super-hydrophobicity micro-structure surface.

The invention discloses a method of regulating and controlling light absorption property of a metal surface by picosecond pulse laser. The method comprises the following steps: irradiating the metal surface by picosecond pulse laser; carrying out laser ablation for removal and self-assembly of the metal surface induced by picosecond pulse laser to obtain a micro-nano dual-scale structure on the metal surface thus realizing regulation and control of the light absorption property of the metal surface. The method disclosed by the invention fully exerts a picosecond laser preparation rule or the micron structure in random distribution as well as capacity of forming the self-assembled nanostructure, and is agile and controllable in processing process, low in processing cost and high in efficiency, so that the method is an economical and practical method of regulating and controlling the light absorption property of the metal surface.

In pulsed-laser apparatus for filamentary cutting a glass-sheet, a laser-beam is focused by a plano-convex focusing lens into the glass-sheet through a first surface of the sheet to a point close to a second surface of the sheet. Pulses from the laser are delivered in repeated bursts. The laser-beam fills the clear-aperture of the lens such that uncorrected spherical aberration in the focusing lens causes radial modulation of the beam between the lens and the focus point. This provides that each burst of pulses generates a filament extending between the first and second surfaces of the sheet.

The invention provides a double light path green light micropore processing device, which comprises a picosecond pulse laser, a nanosecond pulse laser, a light path calibration system and an optical focusing system, wherein the output end of the picosecond pulse laser is provided with a first reflecting mirror; the output end of the nanosecond pulse laser is provided with a second reflecting mirror; the first reflecting mirror and the second reflecting mirror are connected with a third reflecting mirror; the output end of the third reflecting mirror is provided with an optical shutter; the output end of the optical shutter is connected with a beam expanding lens; the output end of the beam expanding lens is connected with a fourth reflecting mirror; and the fourth reflecting mirror is connected with the optical focusing system through the light path calibration system. The two lasers taking the light pulse length as nanoseconds and picoseconds are adopted, the selection of light beams is controlled by a light path selection system, the use of one laser for the processing is allowed, and the two lasers can also be alternately used during the processing. A double light path system maintains the advantage that the laser processes micropores, and can aim at different processing finenesses and cost requirements to flexibly select processing modes.

The invention relates to an STED (stimulated emission depletion)-based device and method for measuring a smooth free-form surface sample, belonging to the field of the optical microscopic measurement. The device comprises a first picosecond pulse laser, a first conduction optical fiber, a first collimator objective, a first plane reflecting mirror, a second picosecond pulse laser, a second conduction optical fiber, a second collimator objective, a second plane reflecting mirror, a vortex-shaped phase modulation plate, a half-wave plate, a first dichroscope, a second dichroscope, a quarter-wave plate, a focusing object lens, a coating sample, a three-dimensional micro-displacement carrier table, an optical filter, a collection object lens, a pin hole and a photoelectric detector. The surface of the sample is coated with a fluorescent membrane, so that an industrial sample can be measured by utilizing the STED microscopy; meanwhile, the fluorescent membrane radiates fluorescence in different directions under the illumination of the laser, so that the problem that the signal light is difficult to collect caused by the mirror reflection of the light beam on a smooth free-form surface can be avoided. By adopting the device and method, the surface appearance of the smooth sample with a large angle between a normal and the optical axis direction can be high precisely measured.

The invention discloses a gain narrowing controlled all-fiber laser amplifier for high-power picosecond pulses. The laser amplifier comprises an all-fiber picosecond seed resource. An optical fiber amplifier is connected to an output end of the all-fiber picosecond seed resource, and an output module is connected to an output end of the optical fiber amplifier; the all-fiber picosecond seed resource is a mode-locked laser in an all-fiber ring cavity structure and comprises a pump laser, a wavelength division multiplexer, a gain optical fiber, an output coupler, a first polarization controller, a polarization beam splitter, a second polarization controller and a polarization independent isolator; and a polarization-maintaining output end of the polarization beam splitter serves as an output end of the all-fiber picosecond seed resource, a non polarization-maintaining output end of the polarization beam splitter is connected with an input end of the polarization independent isolator, the second polarization controller is fixed on an optical fiber between the polarization beam splitter and the polarization independent isolator, and an output end of the polarization independent isolator is connected with the other input end of the wavelength division multiplexer, accordingly, an all-fiber ring structure is formed. By means of the gain narrowing controlled all-fiber laser amplifier for high-power picosecond pulses, long-term stable high-power picosecond pulse laser is obtained easily, and the manufacture cost of a high-power optical fiber laser system can be reduced.

The invention relates to a pretreatment method and system for a material surface before laser welding. The method comprises the following steps: firstly cleaning the surface of a sample by picosecond pulse laser, acquiring surface morphology of the sample in real time by image acquisition equipment while the surface of the sample is cleaned by virtue of the picosecond pulse laser, and judging whether the surface of the sample is clean or not according to the surface morphology of the sample, if the surface of the sample is not clean, continuing to clean the surface of the sample by virtue of the picoseconds pulse laser; if the surface of the sample is clean, turning off the picoseconds pulse laser, and carrying out blackening treatment on the surface of the sample by virtue of femtosecond laser; during the blackening treatment, monitoring the blackening condition of the surface of the sample in real time by the image acquisition equipment, when the surface of the sample is completely blackened, turning off the femtosecond laser, thus completing pretreatment on the material surface before welding. The method provided by the invention has the advantages that strong reflection action of the sample on lights can disappear, a micro-nano structure is formed on the surface, absorption efficiency of a material on laser in a laser welding process is greatly improved, and laser welding efficiency and quality are effectively improved.

The invention relates to a feedback type high-peak-power picosecond-pulse fiber laser system. A pulse shaping unit is added to the rear of a seed source to shape pulses, the pulse width of the seed source is compressed, the waveform of the seed source is improved, and the quality of seed light is improved. A fiber isolator and a narrow-band filter are connected to the front of a pre-amplifier stage and the front of a main amplifier stage respectively, harmful ASE is filtered out, and the stability of the system is improved. A red light indicator is added between the pre-amplifier stage and the main amplifier stage, and thus the safety and the flexibility of operation on a laser are improved. Photodiodes are connected to the rear of the seed source and the rear of the main amplifier stage respectively, and real-time protection and dynamic power regulation of the laser are achieved through a master control unit. The feedback type high-peak-power picosecond-pulse fiber laser system is an all-fiber system, and thus the mechanical stability and the adaptability to the environment of the system can be effectively improved. The quality of light beams of the laser is improved through a fiber grating, the narrow-band filter and a pattern adapter, the nonlinear effect in a doped fiber is effectively suppressed, and high-peak-power picosecond-pulse laser output is achieved.

The invention provides a lithium ion battery, a laser manufacturing method thereof and a laser washing device. Coatings at the specific surface positions of battery pole pieces can be eliminated efficiently, environmentally and stably at high quality, so that the manufacturing technology of the lithium ion battery is simplified, and the manufacturing efficiency is improved. The laser manufacturingmethod comprises the following steps: carrying out die cutting to manufacture a first battery pole piece with a lug; manufacturing a lithium iron phosphate coating with a first thickness on an aluminum foil base body; determining an area to be washed of the aluminum foil base body, and adopting picosecond pulse lasers to scan the lithium iron phosphate coating in the area to be washed in a linearlight spot manner, so that expansion and gasification occur on the lithium iron phosphate coating, the lithium iron phosphate coating is separated from the aluminum foil base body, and an area to bewelded separated from the lithium iron phosphate coating is formed; welding a pole piece in the area to be welded so as to form a second battery pole piece; and combining and connecting the first battery pole piece and the second battery pole piece so as to form the lithium ion battery.

The invention relates to a pretreatment method before thermal spraying of a protective coating on the surface of a polyamide resin matrix composite. Through the pretreatment technology of combining resin matrix composite surface modeling and metal (or alloy) bottom layer priming, effective deposition of protective facing particles is achieved, and bonding force between the coating and a matrix isgreatly increased, wherein surface modeling adopts the laser etching technology, and a used tool is a nanosecond or picosecond pulse laser; and bottom layer priming adopts the cold spraying technology, and a used material is metal or alloy powder such as the Al powder or the Cu powder. After the pretreatment technology, the bonding strength and the heat-shock-resisting cycling capacity between theprotective coating and the matrix are both greatly improved.

The invention discloses a picosecond pulse optical fibre laser which comprises a main cavity resonator and an outer cavity feedback part. A semiconductor laser is adopted as a pumping source; a dichroic mirror and double envelope optical fibre mixing with ytterbium form the main cavity resonator which is coupled to an outer cavity through a collimating lens; a acoustooptic modulator AOM in the outer cavity adopts Raman-Nath diffraction; and a blazed grating outputs zero-level diffraction light generated by a signal light and feeds back any level light in high-level light to the cavity resonator. The invention has simple structure and high cost performance, can realize wide-tune, narrow-line-width and stable picosecond pulse laser output and can be widely applied to the fields of laser processing, laser medical treatment, laser marking, seed light source, etc.

The invention provides a picoseconds-pulse-based high-precision laser distance measuring device. The device combines a picosecond pulse laser technology and a high-speed photoelectric detection technology, and adopts a picosecond pulse laser as a laser emission source and a high-speed PIN photoelectric detector as a receiving unit. A laser light source works in a pulse mode, so the laser transmission power density is high, and consideration is given to the advantages of long measuring distance and high distance measuring precision. The overall device is stable and reliable; the precision for measuring a target away from dozens of kilometers reaches 1 millimeter; and the distance measurement precision is improved by 1,000 times compared with a conventional nanosecond pulse laser distance measuring technology. The device has an ingenious structure design, is simple and practical, and can be used for high-precision measurement of aeronautics and astronautics, marine survey and long distance.

The invention discloses a method for quickly measuring the thickness of a metal coating. The method for quickly measuring the thickness of the metal coating includes that using a picosecond pulse laser to corrode a sample under such special conditions of single-point corrosion, 20 Hz of pulse frequency and 875 micrometers of defocusing distance, obtaining a time-resolved figure capable of intuitively distinguishing coating metal from base metal through an inductively coupled plasma mass spectrometry, confirming the junction point of the coating metal and base metal in the time-resolved figure so as to confirm the corroding time for corroding the coating metal, using the standard piece of the same coating as a standard to calculate the unit pulse corrosion quantity of the metal coating, and calculating according to the unit pulse corrosion quantity and corrosion time to obtain the coating thickness. The method for quickly measuring the thickness of the metal coating realizes the quick and non-destructive detection for the coating thickness, is not limited by the conductivity of the metal coating and does not require sample shape, and moreover, the method for quickly measuring the thickness of the metal coating is capable of precisely distinguishing the boundary of two layers of metal and high in detection precision.

The invention discloses a tens-of-megahertz high-repetition-frequency nanosecond all-optical fiber laser amplifier. The amplifier comprises a single-mode optical fiber seed source, an optical fiber stretcher, an optical fiber power amplifier and a signal light output system; the single-mode optical fiber seed source is a high-repetition-frequency picosecond pulse laser for realizing passive mode locking based on a semiconductor saturable absorber; the optical fiber stretcher is composed of a chromatic dispersion device and an optical fiber communication device used in cooperation with the chromatic dispersion device, and is used for stretching a front-stage picosecond pulse to an order of a few nanoseconds; and the optical fiber power amplifier is a main oscillation power amplifier which is formed by cascading multistage optical fiber amplifiers. Parameters of a resonant cavity are optimized, and an obtained tens-of-megahertz high-repetition-frequency mode-locking picosecond pulse is injected into the optical fiber stretcher, so that stable nanosecond high-repetition-frequency pulse output is achieved; then the pulse is subjected to multistage amplification by adopting a gain optical fiber; and finally high-repetition-frequency high-power nanosecond pulse output is realized. Moreover, the system realizes an all-optical fiber mode, and is stable in work and high in reliability.

The invention discloses a tunable narrow-line-width picosecond pulse laser device, comprising a pulse driving circuit, a semiconductor laser device, an annular device, an optical fiber optical grid, a coupling device, a spectrum analysis unit, a main control unit and a micro-spur traction unit, wherein the pulse driving circuit outputs pulse current to drive the semiconductor laser device to generate one-grade relaxation vibration wide spectrum pulse laser; the pulse laser penetrates through the annular device to be reflected by the optical fiber optical grid; then reflected laser output by the annular device enters the coupling device; the reflected laser with the greater energy is output through an output light port of the coupling device; the reflected laser with the smaller energy is output through a feedback light signal port of the coupling device; the reflected laser with the smaller energy is analyzed and processed by the spectrum analysis unit and the main control unit; and the main control unit drives the micro-spur traction unit and the micro-spur traction unit to carry out micro-spur traction on the axial direction of the optical fiber optical grid. The tunable narrow-line-width picosecond pulse laser device has the advantages of simple structure, easiness for operation, good stability, multi-pulse adjustability, high tuning precision and the like.

The invention discloses a method for measuring PDE and Pct spatial two-dimensional distribution of a silicon photomultiplier. The method comprises the following steps: placing the silicon photomultiplier in an electromagnetic shielding box, and installing the silicon photomultiplier on a nanometer displacement platform; using a picosecond pulse laser driver to enable a laser head to irradiate picosecond laser beams, and focusing the picosecond laser beams into light spots on the surface of the silicon photomultiplier through a pinhole light-transmitting sheet in the microscope; powering the silicon photomultiplier by a stabilized power supply, amplifying an output avalanche pulse signal by a high-speed low-noise amplifier, and then inputting the amplified signal into a digital oscilloscopeto observe the waveform of the avalanche pulse; and controlling a nano displacement table to move, calculating a group of PDE and Pct at each position through the total pulse counting rate and the background counting rate under different photon equivalent thresholds, and finally drawing a spatial two-dimensional distribution diagram through multiple groups of PDE and Pct data. The relative lightdetection efficiency and optical crosstalk probability spatial two-dimensional distribution information of the silicon photomultiplier can be obtained at room temperature without low-temperature refrigeration.

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.

Provided is a method for inducing the phase-change material film crystallization by using ultrashort pulse pico-second lasers at different wavelengths, belonging to the technical field of film crystallization. The device includes a control center and a base light source device that are connected, the light emitted by the base light source is irradiated on a film via a lens. The method includes the following steps of (1) plating a film on the selected substrate by means of magnetron sputtering; (2) using the material obtained in (1), and using a basic lens to irradiate the material with the laser in appropriate energy under the same base light source to make the material undergo phase change, wherein the base light is a pico-second pulse laser at the wavelength of 1064nm; or replacing the lens, under the effect of a frequency multiplication crystal, irradiating the material with the laser in appropriate energy as the wavelength changing into 532nm or 355 nm to make the material undergo phase change.

The invention discloses a method and an element structure for realizing the optical recording and electrical reading of information. The method is characterized by laser recording and electrical reading, wherein the laser reading is to complete information recording by forming phase change information points on a phase change thin film by using the action of a picosecond ultrashort laser pulse; and the electrical reading is to realize information reading by using a scanning probe to detect the resistance change in a phase change area. The element structure mainly comprises a transparent substrate, a metal layer serving as a lower electrode and a phase change recording layer serving as a recoding layer. The method combines the characteristics of small pulse width of the ultrashort laser pulse and dramatic resistance change before and after phase change and synchronously realizes quick recording and reading of signal with a high signal to noise ratio.

The invention provides a high-power sub-hundred picosecon pulse laser system, comprising a first semiconductor sensor, a laser collimating and focusing lens system, a dichroscope, a composite crystal, an optical fiber coupling lens, an optical fiber, a second semiconductor laser, a beam combiner, a ytterbium-doped active optical fiber and an output isolator; the composite crystal is composed of a non-transparent window, a YVO4-dopted crystal, a Nd3+ and YVO4 crystal, a semiconductor saturable-absorber, a copper heat sink layer and various coating film layers. The micron-sized thin Nd3+ and YVO4 crystal is used as a laser crystal and the output of sub-hundred picosecon pulse seed light is realized by using the passively Q-switched laser of the semiconductor saturable-absorber; in addition, the pulse seed light is amplified by utilizing an optical fiber amplification technology and the output of the sub-hundred picosecon pulse light with high average power and high peak-value power is obtained. The laser system has narrow pulse width, compact structure and high output power and can be widely applied to the fields such as precision processing, biological fluorescence detection and laser ranging.