214 results about "Ultra short pulse" patented technology

A cornea is reshaped by first creating a first cut in the cornea using an ultra-short pulse laser. The first cut is located below the surface of the cornea and does not extend through the epithelium. A second cut is then created using the ultra-short pulse laser. The second cut creates a corneal flap and intersects with the first cut to create a substantially severed portion of the cornea located between the first cut and the second cut. The severed portion of the cornea is located outside of the visual axis of the eye. The corneal flap is lifted away from the severed portion, and the severed portion is removed from the eye. The corneal flap is moved into the space on the cornea previously occupied by the severed portion. The cornea is thereby reshaped, and the reshaped portion of the cornea has an increased refractive power, correcting for hyperopic and presbyopic conditions.

The present invention includes an apparatus and the method to scale the average power from high power ultra-short pulsed lasers, while at the same time addressing the issue of effective beam delivery and ablation, by use of an optical amplification system.

An optical, wavelet-based fractal modulation of ultra-short light pulses is used as part of a high-bandwidth communications system. The preferred embodiment utilizes the scheme as part of a hybrid wireless optical and RF transmission system for broadband communications among fixed and / or mobile platforms. An ultra-short pulse laser, high-power WDM-ARRAY laser or high-power incoherent light sources may be used. Computer-generated hologram techniques are employed in designing the optical transceiver subsystems for spectral encoding and decoding of wavelet patterns. Part of the design goal is to select a diversity receiver Field-of-View (FOV) in a way that the effects of scintillation are reduced by as much as possible. Compared to existing optical wireless systems, the invention offers a much higher average transmission bit rate and a much smaller bit error rate outage value, thus enabling highly available FSO links. Wireless transceiver will be capable of communications with nearly line-of-sight FSO links and will be more tolerant to shadowing. Also, the optical medium is designed to be more secure than counterparts against any intrusion.

The invention discloses a metal die for coining a super-hydrophobic micro-nanometer surface and a laser manufacturing method thereof. The laser manufacturing method comprises the following steps that an ultra-short pulse laser is used for ablating a metal base material, a symmetrical negative structure of a lotus leaf micro-nanometer structure is obtained on the surface of the metal base material through laser ablating removing, and then the metal die is obtained; the symmetrical negative structure of the lotus leaf micro-nanometer structure is a micrometer-level pit and a nanometer-level substructure on the inner surface of the micrometer-level pit. The invention provides the micro-nanometer coining metal die for coining a non-metal material or a light-metal material so as to form the lotus leaf micro-nanometer structure with the surface being super hydrophobic and the laser manufacturing method of the metal die, and particularly relates to the micro-nanometer coining metal die which is manufactured efficiently in a large area by the utilization of high-power picosecond lasers and the manufacturing method of the metal die. The metal die for coining the super-hydrophobic micro-nanometer surface and the laser manufacturing method of the metal die have the comprehensive advantages that the manufacturing efficiency is high, the micro-nanometer coining die is high in temperature resistance, high in pressure resistance and wide in coning material range, the micro-nanometer structure is precise and adjustable in parameter and the lotus structure is vivid. Moreover, the manufacturing method is far superior than other methods.

An ophthalmological laser system for photodisruptive irradiation of ocular tissue, including a crystalline lens or a cornea. The system includes an ultra-short pulse laser, the radiation of which is focusable as illumination light via an illumination beam path including a scanner unit and focusing optics. A control unit is programmed to execute determining irradiation control data for photodisruptions at irradiation points in an interior of the ocular tissue distributed three-dimensionally and non-equidistantly to create at least one predetermined target incision. The laser system then irradiates the ocular tissue according to the determined irradiation control data.

A compact system for performing laser ophthalmic surgery is disclosed. An embodiment of the system includes a mode-locked fiber oscillator-based ultra-short pulsed laser capable of producing laser pulses in the range of 1 nJ to 5 μJ at a pulse repetition rate of between 5 MHz and 25 MHz, a resonant optical scanner oscillating at a frequency of 200 Hz and 21000 Hz, a scan-line rotator, a movable XY-scan device, a z-scan device, and a controller configured to coordinate with the other components of the system to produce one or more desired incision patterns. The system also includes compact visualization optics for in-process monitoring using a beam-splitter inside the cone of a patient interface used to fixate the patient's eye during surgery. The system can be configured such that eye surgery is performed while the patient is either sitting upright, or lying on his or her back.

The invention relates to a method of the dynamic characteristic traceability calibration of a high-pressure transducer, and calibration equipment, belonging to the technical field of pressure transducer. The method is as follows: exerting a static pressure on a high-pressure transducer to be calibrated, for realizing a frequency area to be zero frequency traceability calibration; on the basis, exerting an ultra-short pulse motivating pressure, testing the frequency responding characteristic of the high-pressure transducer through a test or a metrologic instrument. The method has the advantages that the method uses a common hydraulic pressure calibration method to realize the dynamic characteristic traceability calibration of the high-pressure transducer; because of adopting a pre-exerting static pressure processing method, the reversed pressure received by the transducer to be tested is reduced, thus effectively protecting the expensive transducer, and the frequency service range of the calibration method is 0-1MHz; the pressure value is as high as 800MPa, the calibration method is advanced, has the creative thought, is worthy of being popularized and learned; the adopted calibration equipment has simple structure, low cost, safe calibration process, no damage to the transducer, high calibration pressure value and wide frequency service range which can cover the zero frequency for traceability calibration, and the calibration equipment is worthy of being adopted and popularized.

The present invention provides a method for efficiently machining a work with a very short pulse. A method is used for machining a work such as a board with a laser beam. The method is characterized in that a very short pulse laser beam having a wavelength to which the work is transparent is directed to the front surface of the work toward the back surface and focused, the beam waist of the focused laser beam is located away from the back surface of the work, a beam focus channel long in the light beam traveling direction from the beam waist formed by the auto-focusing action due to the laserbeam propagation in the work is thus formed in the work, a substance in the channel is decomposed by the laser beam, the decomposed substance can be discharged from the back surface, and a cavity is formed in the channel. While forming the cavity, the laser beam is scanned, a machined surface is formed, and thereafter the work can be cut with a weak bending stress. The invention can be applied todivide two substrates opposed to each other, and can be used for dividing a glass substrate of a liquid crystal panel.

The invention discloses a method and a device for manufacturing external modulation high-speed decoy-state quantum light sources. The method includes enabling an ultra-short pulse laser device to emit linearly polarized light pulses with high repetition frequencies; transmitting the linearly polarized light pulses into a high-speed light intensity modulation module; randomly modulating light pulse signals with originally identical intensities to obtain light pulse signals with different light intensities; transmitting the light pulse signals in signal states and decoy states into a polarization state generating light path to randomly generate light in four polarization states; attenuating the light by a light attenuator and then outputting light in nine quantum states. The light in the nine quantum states can have three light intensities and four polarization states. The device comprises the ultra-short pulse laser device, the high-speed light intensity modulation module, the polarization state generating light path, a high-speed light phase modulation module, the light attenuator and a high-speed logic control chip. The method and the device have the advantages that the intensities of the light pulses are externally modulated, the modulated light pulses in the different quantum states are excellent in consistency, and accordingly the problem of security vulnerability due to inconsistency in the shapes, the amplitude and the pulse widths of existing light pulses which are internally modulated can be solved.

The invention discloses a wide-view-field chromatography hyperspectral microscopic imaging method and device based on space-time focusing, and belongs to the technical field of microscopic spectral imaging and analytical chemistry. According to the method, ultra-short pulse lasers are generated through an ultra-short pulse laser source, focusing lines are generated in a sample through space-time focusing, excited fluorescence is collected, stray light is filtered out through con-focal optical slits, spectral information (x, lambda), of the sample is acquired through fluorescence spectral information collecting, and finally sample (x, lambda, y, z, t) five-dimensional information is acquired through three-dimensional space scanning and delayed scanning. The device comprises the ultra-shortpulse laser source, a light beam conversion system, a line scanning system based on space-time focusing, an optical microscopic system and a filtering and synchronous spectrum con-focal detection system. Acquisition of the spectral information in the filtering and synchronous spectrum con-focal detection system is synchronous with line scanning trigger signals in the line scanning system in combination with the space-time focusing technology. The method and device have the advantages of being wide in view field, high in space resolution, high in time resolution, high in spectral resolution andthe like.

The invention discloses an ultra-short pulse solid laser with continuous adjustable repetition frequency. The ultra-short pulse solid laser comprises a pumping source, a gain medium, a resonant cavity, a parallel planar reflector set, a mode locking device and a coupling output mirror, wherein the pumping source is used for pumping sufficient gain required by the gain medium; the resonant cavity is used for forming a condition for laser back-forth oscillation; the mode locking device is used for realizing modulation of a longitudinal mode of the laser so as to realize ultra-short pulse; the pumping source is used for outputting laser through optical fiber coupling; the laser is coupled into the gain medium after being shaped; laser emitted by the gain medium forms oscillation laser through the resonant cavity; the oscillation laser is converged to the mode locking device through a concave surface reflector of the resonant cavity; the mode locking device forms multiple back-forth oscillation and modulation on the laser by means of the resonant cavity and the parallel planar reflector set; and finally, continuous ultra-short pulse is output through the coupling output mirror.

The invention discloses a system for measuring linear and non-linear magneto-optical Kerr rotation, which comprises an ultra-short pulse laser, a helium-based closed-cycle refrigerator, an electromagnet, a laser-pumping optical path, a laser-detection optical path, a linear Kerr signal collection optical path, a non-linear Kerr signal collection optical path, a lock-in amplifier signal collection system and a laser spot monitoring system, wherein the helium-based closed-cycle refrigerator is provided with optical windows and used for controlling the temperature of a sample; the size of the air gap and the magnitude of the magnetic field of the electromagnet are adjustable; the laser-pumping optical path is used for leading in the laser inputted by the ultra-short pulse laser and focusing the laser on the surface of the sample inside the refrigerating head, so as to excite the sample; the polarization plane of the laser-detection optical path rotates after a beam of laser outputted by the ultra-short pulse laser is reflected by the sample; the linear Kerr signal collection optical path is used for collecting the base-frequency signal of the detection laser; the non-linear Kerr signal collection optical path is used for receiving the frequency-doubled signal of the detection laser; the lock-in amplifier signal collection system is used for filtering and amplifying the signals and transmitting the signals to a computer for processing; and the laser spot monitoring system is used for accurately controlling the overlap ratio of the pumped beam laser spot and the detected beam laser sport. The system provided by the invention for measuring the linear and non-linear magneto-optical Kerr rotation is capable of simultaneously adjusting the temperature and the intensity of the magnetic field applied to the sample and achieving the measurement of the linear and non-linear magneto-optical Kerr effect on a temperature-variable steady-state basis or a time-resolved dynamic basis.

The invention relates to an ultra-fast laser continuous imaging device and method based on frequency domain space-time transformation, and belongs to the field of ultra-fast imaging. The device comprises an ultra-short pulse laser, a chromatic dispersion delayer, a time domain frequency shaping device, a first wide wave band reflector, a second wide wave band reflector, a space domain frequency shaping device and a two-dimensional CCD spectrograph. According to the method, the ultra-short pulse laser is used for producing the laser light within the spectral range, the chromatic dispersion delayer is used for changing the delay interval, the time domain frequency shaping device and the space domain frequency shaping device are used for shaping the frequency components of the laser light, the two-dimensional CCD spectrograph is used for carrying out detecting after the laser light passes a sample, and then the electron dynamic state of the sample can be obtained. By means of the device and method, the time resolving power can be improved to the femtosecond level, continuous shooting is achieved, complete shooting is carried out on the process without the repeated experiment condition, the shooting period and the shooting number can be controlled and adjusted, and the spectrograph is used for replacing an imaging system, and implementation is easy.

The invention discloses a MHz photonic crystal fiber ultra-short pulse laser based on a multichannel pulse compressor. The laser comprises a diode pumping source, a photonic crystal fiber, an intra-cavity pulse compressor, a semiconductor saturable absorber mirror and an extra-cavity pulse compressor, wherein the inter-cavity pulse compressor and the extra-cavity pulse compressor respectively are an intra-cavity multichannel pulse compressor and an extra-cavity multichannel pulse compressor. The main bodies of the multichannel pulse compressors are end mirrors in which two concave spherical surfaces are coaxially and oppositely arranged, each end mirror is provided with a rotating ring, and a concave spherical reflector is arranged in the rotating ring. The MHz photonic crystal fiber ultra-short pulse laser has the advantages that the low recurrence frequency of the pulse laser greatly reduces heat accumulation of pulse on components and prolongs the service life of the components, meanwhile, the intra-cavity multichannel compressor and the extra-cavity multichannel compressor with low loss and compact structure overcome the disadvantages of other chromatic dispersion compensation technologies, and the ultra-short pulse laser with low cost, high energy and high peak power output is realized.

The invention relates to a device and a method for processing OGS touch screens. Lasers emitted by a green ultra-short pulse laser are subjected to coaxial beam expansion through a beam expander, light beams after being expanded through the beam expander pass through a 45-degree transflective mirror, and the light path direction is changed; one path of light beams is focused on the lower surface of a work-piece through a first 3D dynamic scanning galvanometer and a first focusing mirror, and the other path of the light beams penetrates through the 45-degree transflective mirror, a second 3D dynamic scanning galvanometer and a second focusing mirror to be focused on the lower surface of the work-piece; a first coaxial charge coupled device (CCD) and a second CCD position the work-piece accurately, capture a positioning mark on the work-piece and calculate a compensation value; and the 3D dynamic scanning galvanometers lift the focus automatically during processing and the work-piece is processed from bottom to top. The two light paths perform optical focusing on the green ultra-short pulse lasers which penetrate through the work-piece to be focused on the lower surface of the work-piece, and energy of the laser is applied optimally and efficiently, and the efficiency is improved.

A fiber grating and thick and tapered fiber temperature and strain test system disclosed by the present invention comprises a femtosecond laser, the output end of the femtosecond laser is connected with the input end of an optical gate, and the output end of the optical gate is connected with the input end of a high-precision mobile platform. The output end of the high-precision mobile platform isconnected with the input end of a spectrograph, and the input end of the high-precision mobile platform is connected with the output end of a broadband light source. According to the fiber grating and thick and tapered fiber temperature and strain test system and the method thereof, a femtosecond laser processing technology has the technical characteristics of being high in processing precision and efficiency and being simple and convenient to operate in a conventional laser processing technology, also displays the unique advantages in the processing of high precision, high resolution and lowdamage of the fiber micro-nano materials with ultra short pulse width of the femtosecond magnitude and the ultra strong peak power of the thousand trillion watt magnitude. The method does not need aphotosensitive fiber, the grating cycle can be selected flexibly, and an etched grating has the very high thermostability.

The invention discloses a multi-purpose bidirectional passive mode-locked full-fiber laser system and aims to solve a technical problem that it is difficult for a convention fiber laser device to output two types of ultra-short optical pulses simultaneously. The system comprises a pumping source (1), a wavelength division multiplexer (2), an erbium-doped gain fiber (3), a 2*2 output coupler (4), a first 3dB optical coupler (5), a second 3dB optical coupler (6), a first polarization-dependent isolator (7), a first polarization controller (8), a second polarization-dependent isolator (9), a second polarization controller (10), a dispersion compensation fiber (11) and a single-mode fiber (14). The 2*2 output coupler (4) outputs a bidirectional mode-locked pulse. The first output end (12) of the 2*2 output coupler (4) is connected with the single-mode fiber (14) located outside a cavity and is used for the out-of-cavity time-domain compression of the output pulse to obtain a high-peak-power ultra-short pulse. The second output end (13) of the 2*2 output coupler (4) directly outputs a high-energy dissipative soliton resonance pulse. The system is low in cost and wide in application range, and can be used as a high-peak-power femtosecond pulse light source and a high-energy picosecond and nanosecond pulse light source, and can also be used as a seed source of a high-energy pulse amplifier.

The invention discloses a method for removing a coating of a hot-rolled steel sheet by virtue of an ultra-short pulse laser galvanometer. The method comprises the following steps: (1) cleaning the surface of a to-be-welded hot-rolled steel sheet with an Al-Si coating; (2) fixing the cleaned hot-rolled steel sheet to a frock clamp, and adjusting ultra-short pulse laser emitted by a laser to be vertical to the hot-rolled steel sheet; (3) turning on the laser to remove the Al-Si coating of the hot-rolled steel sheet according to technological parameters for removing the Al-Si coating by virtue of the ultra-short pulse laser galvanometer; and (4) turning off the laser, and taking down the hot-rolled steel sheet with the Al-Si coating, thereby finishing the process of removing the Al-Si coating of the hot-rolled steel sheet. By virtue of the method, a light splitting device does not need to be utilized; by virtue of a galvanometer scanning method, the energy density is relatively high, the removal efficiency is high, the size of the removed coating can be adjusted, and furthermore, the removing thickness of the coating can be controlled by controlling the laser power.

The invention belongs to the technical field of key distribution in secure communications, relates to a secure and high-speed key distribution scheme, and especially provides a secure and high-speed key distribution system and a method thereof based on a chaotic synchronization common channel feature. The system comprises a wideband random light source, a main fiber coupler, a common channel, an ultra-short pulse mode-locked laser, an Alice communicating party, and a Bob communicating party, wherein the Alice communicating party comprises a first optical feedback chaotic semiconductor laser, afirst fiber coupler, a first optical switch, a first privacy key module, a first register, and a first key filter; and the Bob communicating party comprises a second optical feedback chaotic semiconductor laser, a second fiber coupler, a second optical switch, a second privacy key module, a second register, and a second key filter. The invention is reasonable in structure, clever in design, effectively guarantees the key distribution security, and adequately uses the bandwidth advantage of a chaotic optical signal, which greatly improves the key distribution rate, and is appropriate for secure communication.

The invention provides a method for generating high-speed parallel true random numbers with an ultra-high scalability. The method comprises the steps that firstly, spectrum cutting is conducted on an ultra-short pulse sequence generated by an optical device, so that N paths of ultra-narrow-band ultras-short pulse sequences are obtained; secondly, time domain widening is conducted, so that large-pulse-width narrow-band short pulse sequences are obtained and then converted into electrical signals; thirdly, the signals enter an analog-digital converter to be converted into corresponding high and low levels, and therefore N paths of independent true random numbers with the repetition frequency being f are generated. The high-speed parallel true random number sequence generated through the method does not have periodicity, the code rate of each path can reach the magnitude order of 10 Gbps, at least 1000 paths of independent parallel true random numbers can be output at the same time, the scalability of an existing parallel true random number generator is improved at least 3-4 magnitude orders, and the modern large-scale parallel computing and high-speed secretive network communication demands can be met to a large extend.

A method for generating ultra-short pulse amplified Raman laser light. Short pulse laser light is amplified, and a portion thereof is introduced into a Raman oscillator to produce compressed laser light. The compressed light is introduced to a first Raman amplifier. The remainder of the short pulse laser light is introduced to a polarizer, and the reflected light is introduced into the first Raman amplifier to pump it. The light transmitted through the first Raman amplifier that has not contributed to pumping is introduced to a beam splitter to produce a second reflected light that is passed to a second Raman amplifier to pump that amplifier. The compressed light is amplified in the first Raman amplifier and introduced to the second Raman amplifier to further amplify it. This further amplified radiation is passed through delay lines to the beam splitter, which passes only first Stokes radiation to generate ultra-short pulse amplified Raman laser light.

The invention discloses a spectrum regulating and controlling device for mid-infrared pulse lasers. In the spectrum regulating and controlling device, near-infrared pulse lasers emitted by a near-infrared pulse laser device and mid-infrared pulse lasers jointly enter an aperiodicity poled crystal through an optical coupling mirror, and are subjected to nonlinear frequency conversion, the near-infrared pulse lasers serve as pump light, different spectrum components of the mid-infrared pulse lasers are subjected to differentiation amplification so that spectrum regulating and controlling can be achieved. According to the spectrum regulating and controlling device for the mid-infrared pulse lasers, the I-type quasi-phase matching technology is adopted, the working temperature of the aperiodicity poled crystal is adjusted, and group velocity mismatching between the near-infrared pump light and mid-infrared signal light in the crystal is eliminated. In this way, the spectrum regulating and controlling device is suitable for femtosecond-magnitude-order mid-infrared ultra-short pulse lasers, and does not need to be chirped and broadened, spectrum shaping can be directly carried out through the near-infrared pulse lasers, and the complex degree of the spectrum regulating and controlling device based on nonlinear frequency conversion is greatly simplified.

The invention discloses a hollow-core anti-resonance optical fiber with a core shift structure, and belongs to the technical field of optics and laser photoelectrons. According to the optical fiber, the bending loss of the optical fiber is greatly reduced and the single-mode transmission characteristic of the optical fiber is improved through the design of a left-right asymmetric cladding structure. Compared with traditional total internal reflection type and symmetrical hollow-core anti-resonance optical fibers, the optical fiber of the invention has the advantages of low bending loss, quasi-single-mode transmission, wide transmission spectrum, low dispersion, high damage threshold and the like. Simulation and experiments prove that compared with a traditional single-circle node-free hollow-core anti-resonance optical fiber, the bending loss of the optical fiber is reduced by one order of magnitude under the condition of a small bending radius. And meanwhile, simulation and CCD imaging also prove that the quasi-single-mode transmission characteristic is relatively good. The optical fiber has huge application prospects in optical fiber sensing, optical fiber gas lasers and high-power ultra-short pulse laser transmission.

The process of forming color inner carving inside glass includes the following steps: converging super-short pulse laser beam with micro objective to selected position inside glass sample while proper micro objective and laser irradiation condition is selected to obtain required laser spot size; moving the platform with glass sample set via computer control and controlling the on-off of laser beam with electronic shutter to form designed shape and pattern with the laser focus inside the glass; and performing heat treatment of the glass after laser irradiation, with the temperature for heat treatment being controlled for fading and development of the formed pattern.

The invention discloses a complex pulse laser deep hole machining device based on Bessel beams. The complex pulse laser deep hole machining device comprises a short / ultrashort pulse laser light source, a two-sided coated planar mirror, a small-aperture diaphragm, a frequency multiplication crystal, a collimating mirror, a 1 / 4 wave plate, a Gauss-Bessel conversion device and a scanning galvanometer; complex pulse laser is utilized for microporous stepwise machining; firstly, the advantage of short pulse laser of being high in machining efficiency is utilized for preliminary machining of micropores, and then the advantages of ultrashort pulse laser of being high in machining precision and having a small heat-affected zone are utilized for removing a recast layer and the heat-affected zone ofpreliminarily-machined micropores. The properties of the Bessel beams of being small in spot diameter and large in focal depth are utilized for processing the micropores with a large depth-diameter ratio; the two-sided coated planar mirror and the small-aperture diaphragm are utilized for coaxial beam combination, then through the frequency multiplication device, the wavelength of the complex laser is unified, the transmission stability of the complex pulse laser in the same optical system is guaranteed, and the machining precision of the complex pulse laser is improved.

The invention relates to a multi-frequency pulse ultrafast laser continuous imaging device and method based on a super-continuum spectrum, and belongs to the field of ultrafast imaging. The device comprises an ultra-short pulse laser, a multi-frequency pulse generator, a pulse frequency divider and a CCD camera. The method comprises the steps: generating laser pulses through an ultra-short pulse laser; generating the super-continuum spectrum through the multi-frequency pulse generator, wherein there is a certain time delay between different frequencies; separating the laser pulses of all the frequencies in space through a pulse frequency divider after passing through a sample, and performing the detection through a CCD camera, thereby obtaining super-fast continuous electronic dynamic image information of the sample. The device and the method can enable the time resolution to reach the femtosecond magnitude, achieve the continuous shooting, and achieve the complete shooting of the process without repeated experiment conditions, wherein the shooting period and the shooting number can be controlled and adjusted. Moreover, the total number of shooting frames is greatly increased and can reach more than 100 compared with an existing ultrafast imaging system.

The invention discloses an iron-doped zinc selenide saturable absorber mirror, a manufacturing method thereof, and a mold-locked fiber laser composed of the iron-doped zinc selenide saturable absorber mirror. The iron-doped zinc selenide saturable absorber mirror comprises a substrate, a high-reflectivity film plated on the substrate, and an iron-doped zinc selenide film plated on the high-reflectivity film. Due to the fact that iron-doped zinc selenide saturable absorber mirror adopts the iron-doped zinc selenide film as a saturable absorber, and the iron-doped zinc selenide film has a high damage threshold and can be applied to development of high-power lasers, the blank of lack of high-damage-threshold saturable absorber mirrors or high-damage-threshold saturable absorbers in the field is filled up. The mold-locked fiber laser formed on the basis of the iron-doped zinc selenide saturable absorber mirror obtains laser beams through double-cladding gain fibers, a locked mode is achieved by modulating the laser beams with the iron-doped zinc selenide saturable absorber mirror, and then ultra-short pulse laser beams are obtained.