234 results about "Nonlinear optics" patented technology

The invention discloses a spirofluorene xanthene material and a preparation method and an application method thereof, and relates to application of the material in the fields such as organic electroluminescence, photovoltaic cell, organic electrical storage, organic nonlinear optics, chemical and biological sensing, organic laser and so on. The material has the following structure. The material has the advantages that (1) the material is prepared through a one pot process and has simple steps and mild conditions; (2) the material has the advantages of spirobifluorene materials, and shows high thermal stability and vitrification temperature; and (3) the material has high hole or electron mobility and so on. An electroluminescent device prepared by utilizing the material achieves satisfactory results in aspects such as illumination, luminous efficiency, voltage withstand stability and so on.

In conducting laser annealing using a CW laser or a quasi-CW laser, productivity is not high as compared with an excimer laser and thus, it is necessary to further enhance productivity. According to the present invention, a fundamental wave is used without putting laser light into a non linear optical element, and laser annealing is conducted by irradiating a semiconductor thin film with pulsed laser light having a high repetition rate. A laser oscillator having a high output power can be used for laser annealing, since a non linear optical element is not used and thus light is not converted to a harmonic. Therefore, the width of a region having large grain crystals that is formed by scanning once can be increased, and thus the productivity can be enhanced dramatically.

A beam control system and method which utilizes the wavefront reversal property of nonlinear optical phase conjugation to permit incorporation of a liquid crystal OPA within the low power legs of the beam control system, thereby affording the advantages of the OPA without the power limitations thereof. The invention is adapted for use with a beacon for illuminating a target with a first beam of electromagnetic energy. The system includes a telescope (1010) for receiving a target return comprising a reflection of the first beam from the target. An optical phased array (1050) is included for correcting for aberrations in the wavefront of the target return. A mechanism is included for ascertaining the correction applied by the optical phased array to the target return. The mechanism applies the correction to a third beam which ultimately is the output beam. In the illustrative embodiment, the first beam of electromagnetic energy is optical energy and the mechanism includes a first phase conjugate mirror (1091) adapted to conjugate electromagnetic energy output by the third mechanism and a second phase conjugate mirror (1092) adapted to conjugate the output of the first phase conjugate mirror. The fourth mechanism further includes an amplifier (1088) for boosting the signal output by the second phase conjugate mirror (1092) to provide the output beam.

A device for amplifying light pulses has an optical stretcher, in which the light pulses of a pulsed laser light source are temporally stretched, and an optically pumped amplifier fiber, in which the light pulses are amplified and, at the same time, temporally compressed. In order to improve such a system with regard to the pulse duration and the pulse energy that can be achieved, the amplifier fiber has a positive group velocity dispersion, whereby the amplifier fiber has non-linear optical properties, so that the optical spectrum of the light pulses is broadened during the amplification process, taking advantage of non-linear self-phase modulation.

The invention relates to new polymerizable mesogenic or liquid crystalline compounds comprising a terminal cyclohexylphenyl group wherein the phenyl group has polar substituents, to polymerizable mesogenic or liquid crystalline mixtures and anisotropic polymers prepared thereof, and to the use of the new compounds and the mixtures and polymers prepared thereof in optical and electrooptical devices, adhesives, synthetic resins with anisotropic mechanical properties, cosmetics, diagnostics, liquid crystal pigments, decorative and security applications, nonlinear optics, optical information storage, electronic devices like organic field effect transistors (FET or OFET) or electroluminescent devices.

A system for detecting haemozoin in a sample, said system including a light source for exciting the sample with an optical signal to generate a non-linear optical response, and a detector for detecting the generated non-linear optical response from the excited sample. A method for detecting haemozoin in a sample, the method including exciting the sample with an optical signal to generate a non-linear optical response from the sample, and detecting the emitted non-linear optical signal from the excited sample.

The invention relates to a normal-temperature normal-pressure femto-second CARS (Coherent Anti-stokes Raman Spectroscopy) time-resolved spectrum measuring system which relates to the technical field of nonlinear optics and solves the problem of multiple limiting factors of traditional femto-second CARS time-resolved spectrum measuring experiment. Beams output by a femto-second laser are adjusted through a series of reflectors and optical delay lines by the system to form three bundles of beams which have approximate energy and are respectively positioned on three peaks of a square on the vertical direction of the beams, the beams are focused to a sample pool and then emit a new beam along a specific angle, i.e. a CARS signal, the CARS signal is filtered through a filter plate, then received by a probe and input to a monochromator, the data acquisition of an electrical signal converted by a photomultiplier is carried out by utilizing BOCCAR, and the data are input to a computer for data processing. The invention can carry out femto-second CARS time-resolved spectrum measurement under the experimental conditions of normal temperature and normal pressure and is applicable for the femto-second CARS spectrum measurement of gas samples and liquid samples in a static sample pool.

The invention relates to a passive mode-locking ultrashort pulse all-fiber laser with a waveband of 2.0 microns and belongs to the field of a laser technology and nonlinear optics. The passive mode-locking ultrashort pulse all-fiber laser with the waveband of 2.0 microns mainly comprises a laser pumping source, a pumping combiner, thulium-doped or thulium-holmium-codoped rear earth doped fibers, a circulator, a saturable absorber, a laser beam splitter, an isolator, a fiber bragg grating, a polarization controller and the like. The thulium-doped or thulium-holmium-codoped rear earth doped fibers are used as a gain medium; the saturable absorber is used as a passive mode-locking device; and the output of an ultrashort laser pulse which is in the waveband of 2.0 microns and has high pulse energy is realized. Due to the adoption of the all-fiber structure design, the passive mode-locking ultrashort pulse all-fiber laser with the waveband of 2.0 microns has the advantages of simple structure, high environment stability and the like, and the industrialization application is easy to realize.

A waveguide cores consisting of a subwavelength grating permits transmission of light without diffraction in a discontinuous manner, wherein the energy is provided by field hopping between subwavelength material segments of higher index. The use of alternating segments permits design of waveguides having desired effective index, mode confinement factor, birefringence, polarization mode or mode dispersions, polarization dependent loss, thermal sensitivity, or nonlinear optical coefficient. An optical system comprises a waveguide having such a core, clad on at least one side, extending between two ends, and wavelength-limiting optical components in optical communication with the ends.

The invention discloses a double-coating large-mode-area photon crystal flysecond laser directly obtaining micro joule-level single pulse energy, belonging to the field of laser technique and nonlinear optics, where the laser main body is based on double-coating large-mode-area photon crystal optical fiber of polarization-protection structure and adopts high-power LD laser to directly pump; the laser uses grating pair to compensate dispersion, starts mode locking with the help of semiconductor saturable absorber mirror (SESAM), and controls polarization by wave plate and polarization beam splitter and implements tunable output; laser resonant cavity keeps net positive dispersion inside and runs in self-similar mode locking mode and outside-cavity dispersion compensation is made on the output pulse and the pulse is 100-200fs wide. And the advantages: the laser has good stability, and the output pulse has high energy and high repeating frequency. And the invention can effectively avoid split of pulse running at high energy.

The invention relates to new polymerisable mesogenic or liquid crystalline compounds comprising a laterally substituted cinnamate group, to polymerisable mesogenic or liquid crystalline mixtures and anisotropic polymers prepared thereof, and to the use of the new compounds and the mixtures and polymers prepared thereof in optical and electrooptical devices, adhesives, synthetic resins with anisotropic mechanical properties, cosmetics, diagnostics, liquid crystal pigments, decorative and security applications, nonlinear optics, optical information storage, electronic devices like organic field effect transistors (FET or OFET), electroluminescent devices, or as chiral dopants.

An optoelectronic transducer comprises a unipolar, intraband active region and a micro-cavity resonator. The resonator includes a 2D array of essentially equally spaced regions that exhibits resonant modes. Each of the spaced regions has a depth that extends through the active region and has an average refractive index that is different from that of the active region. The refractive index contrast, the spacing of the spaced regions, and the dimensions of the spaced regions are mutually adapted so that the array acts as a micro-cavity resonator and so that at least one frequency of the resonant modes of the array falls within the spectrum of an optoelectronic parameter of the active region (i.e., the gain spectrum where the transducer is a laser; the absorption spectrum where the transducer is a photodetector). In a first embodiment, the transducer is an ISB laser, whereas in a second embodiment it is a unipolar, intraband photodetector. In other embodiments, the laser is a surface-emitting ISB laser and the photodetector is a vertically-illuminated detector. In another embodiment, a nonlinear optical material is optically coupled to the micro-cavity resonator, which in one case allows an ISB laser to exhibit bistable operation.

The invention discloses an all-fiber pulsed laser, and belongs to the field of laser technology and nonlinear optics. The all-fiber pulsed laser includes a pump source (1), an optical combiner (2), a first gain fiber (3), a second gain fiber (4), a first reflective fiber Bragg grating (5), a second reflective fiber Bragg grating (6), an optical isolator (7), a full reflection mirror (8) and a circulator (9), and adopts a structure of linear cavity or annular cavity. By use of the rare earth-doped gain fibers as a laser modulator, with no additional external modulation source and an all-fiber structure, ultrashort pulse laser output of high stability, high power, high energy and high efficiency is achieved. Compared with a semiconductor saturable absorption mirror (SESAM) and graphene (Graphene) modulation Q, mode-locking technology, the all-fiber pulsed laser employs gain fiber for direct pulse modulation, has the advantages of simple design, compact structure and high stability, and is easier to industrialize.

A laser pulse shape measuring system to measure the pulse shape of pulses generated by a pulsed laser. Each pulse includes a pulse width and a peak wavelength. The system includes: a beam splitter coupled to the laser to separate each of the pulses into a test pulse and a probe pulse; a pulse width compression means coupled to the beam splitter to compress the pulse width of each probe pulse; a controllable delay means to control a time offset between each test pulse and a corresponding probe pulse; a nonlinear optical medium arranged such that the test beam path and the probe beam path intersect within it to generate wavelength converted pulses corresponding to intersecting pairs of pulses; a detector coupled to the nonlinear optical medium to detect the pulse energies of the wavelength converted pulses; and a processor to determine the pulse shape of the laser pulses.

An amplified commonly mode-locked and / or Q-switched external cavity laser device with a plurality of gain elements and a plurality of amplifying elements is described. The device produces amplified optical pulses of picosecond to nanoseconds duration. The amplified pulses can be used in applications requiring large optical pulse energy and also high average optical power, such as material processing, nonlinear optics, extreme UV spectroscopy, and generation of x-rays.

A nonlinear optical crystal having a chemical formula of YiLajAlkB16O48, where 2.8≦i≦3.2, 0.8≦j≦1.2, i and j sum to about four, and k is about 12 is provided. The nonlinear optical crystal is useful for nonlinear optical applications including frequency conversion. Nonlinear optical crystals in a specific embodiment are characterized by UV blocking materials (e.g., some transition metals and lanthanides) at concentrations of less than 1,000 parts per million, providing high transmittance over portions of the UV spectrum (e.g., 175-360 nm).

A harmonic holography (H2) technique and system that combines holography and nonlinear optics that enables holographic recording of 3D images with femtosecond framing time are provided. The H2 technique records holograms with second harmonic (SH) signals scattered off specialized nanocrystals that are functionalized to label specific protein or other biomolecules in a living organism. The capability of generating second harmonic radiations is specific to materials with noncentrosymmetric crystalline structures only, and χ(2) vanishes for all other types of materials. Therefore, a sharp contrast is formed when particles of noncentrosymmetric structures are dispersed in a medium of other species, pumped at a fundamental frequency, and imaged at the second harmonic frequency. The new scheme described herein provides a sound basis for a new type of contrast microscopy with enormous potential in molecular biomedical imaging.

The present disclosure relates to a generally-applicable measurement technique based on coherent quantum enhancement effects and provides embodiments with nonlinear optics. The technique utilizes parametric nonlinear processes where the information-carrying electromagnetic quanta in a number of electromagnetic modes are converted phase coherently to signature quanta in a single mode or a few modes. The phase coherence means that while the quanta before conversion may have unequal or uncertain phase values across the modes, the signature quanta converted from those different modes have the (near) uniform phase. This can lead to significant increase in the signal to noise ratio in detecting weak signal buried in strong background noise. Applications can be found in remote sensing, ranging, biological imaging, field imaging, target detection and identification, covert communications, and other fields that can benefit from improved signal to noise ratios by using the phase coherent effect.

A device and a system, based upon Deep Optical Scanning (DEOS), for the detection of certain cancers such as breast cancer and the determination of their response to therapy. DEOS is based upon the nonlinear optical interaction of incident laser generated light with tissue. The cancers may either be subsurface or on the surface. The system includes hardware and software components that form subsystems including: an Optical Electronic Subsystem, a Digitization Subsystem, a Parameter Computation Subsystem, an Archive, an Artificial Intelligence Subsystem, and a Presentation Subsystem. The device can be made portable and is non-invasive in its application to a patient. The system can be integrated into a hybrid architecture with other imaging techniques used for the detection of cancers.

The invention discloses a preparation method for 9,9-diaryl thiophene xanthene-10,10-dioxide, and belongs to the field of fine organic synthesis and organic semiconductor material preparation. The preparation method comprises the following steps: using diphenylsulphone as a starting material and tetrahydro furan as a solvent, conducting ortho metalation reaction on diphenylsulphone under the action of n-butyllithium within a temperature range of -78-0 DEG C to obtain a corresponding aryl lithium salt; allowing the aryl lithium salt to react with an added aryl formic ether ester derivative, and performing hydrolysis to obtain a corresponding tertiary alcohol; dissolving the tertiary alcohol and electron-rich aromatic with an acetate or methylene chloride solution, using Lewis acid as a catalyst, and carrying out friedel-crafts reaction to obtain the 9,9-diaryl thiophene xanthene-10,10-dioxide. The preparation method has the advantages that the reactions are easy to control, the operation is simple, the cost is low, the repeatability is good, the productivity is high, and the product quality is high; an organic modular unit and an organic functional semiconductor can be conveniently made; the 9,9-diaryl thiophene xanthene-10,10-dioxide is used in the fields of organic light emitting diodes, organic transistors, organic laser, and organic nonlinear optics, and the like.

The invention relates to an optical parameter oscillator, especially relates to a compact broadband spectrum independently-tunable dual-wavelength parameter oscillator and belongs to the field of laser technology and nonlinear optics. The parameter oscillator comprises a pump laser, a polarization beam splitter, a reflector, a first controller, a second controller, a first coupling optical system, a second coupling optical system, a first chamber mirror, a second chamber mirror, a third chamber mirror, a fourth chamber mirror, a first crystal, a second crystal, a first spectroscope and a second spectroscope. According to the invention, an optical parameter oscillation resonant cavity is adopted to realize dual-wavelength outputting; independent tuning of the center wavelength and wavelength intervals of output light can be independently tuned in a broadband spectrum scope. The power of two paths of output light with different wavelengths can be independently tuned. The pump light source is a non-polarization light source. The compact broadband-spectrum independently-tunable dual-wavelength parameter oscillator of the invention has characteristics of being simple in structure, low in cost, reliable in working and convenient in operation.

The invention relates to a method for improving photoluminescence efficiency of an upconversion material. The method is used for preparing the NaY1-x-yYbxEryF4 upconversion material containing nano-silver particles by a co-sintering process, and the photoluminescence efficiency of the NaY1-x-yYbxEryF4 upconversion material containing the nano-silver particles can be effectively improved by effectively mixing the nano-silver particles with the upconversion material and utilizing a resonance enhancement property of a high-energy local electric field of localization surface plasmon polaritons to the nonlinear optical process. The method disclosed by the invention has the benefits that the emission peak intensity at 411nm, 524nm, 544nm and 657nm can be improved by above 15% under the excitation of incident photons in the wavelength of 980nm, the gain which is above 20% can be obtained in a full spectrum range between 300-800nm, and a fluorescence enhancement effect is significant.

The invention relates to a 2-micrometer waveband all-polarization-maintaining locked-mode ultrafast pulse fiber laser, and belongs to the field of the laser technology and nonlinear optics. The 2-micrometer waveband all-polarization-maintaining locked-mode ultrafast pulse fiber laser mainly comprises a laser pump source, a polarization-maintaining pump combiner, a polarization-maintaining thulium-doped or thulium and holmium co-doped optical fiber, a polarization-maintaining circulator, a polarization-maintaining isolator, a saturable absorption body or saturable absorption mirror, a polarization-maintaining coupler and a polarization-maintaining passive optical fiber. The thulium-doped or holmium-doped or thulium and holmium co-doped optical fiber is used as a gain medium, and the saturable absorption body or the saturable absorption mirror is combined with a 8-shaped resonant cavity to be collectively used as a passive locked-mode device, so that the 2-micrometer waveband, low-power pump, all-polarization-maintaining and mixed locked-mode ultrafast pulse is outputted. By adopting the structure, the all-optical-fiber welding is realized. The 2-micrometer waveband all-polarization-maintaining locked-mode ultrafast pulse fiber laser has the advantages of low pump power, stable locked mode, simple structure and stable and reliable system locked mode, and not only can be used as a laser light source with excellent performance, but also can be used as a signal seed source to be further amplified.

The invention belongs to the technical field of light beam conversion, in particular to a method for generating a bezier-like light beam through an optical fiber end face growth microcone. The methodcomprises the following steps of: depositing a photopolymer liquid reagent on the end face of a single-mode optical fiber, coupling green laser into the single-mode optical fiber through a lens, and reacting with the photopolymer liquid reagent deposited on the end face of the single-mode optical fiber to form a polymer microcone; wherein the light beam is converted into a bezier-like light beam after passing through the polymer microcone formed by the end face of the optical fiber. The shape of the microcone is controlled by light polymerization parameters such as green laser power, laser exposure time and oxygen diffusion concentration. The working bandwidth of the microcone covers the whole visible light region and even the near infrared band, and can have more than 30 concentric ringsat most, and the generated Bezier-like beam has self-recovery property. The method has the advantages of high efficiency, low cost and convenience, and can be widely applied to the fields of particlecontrol, optical imaging, nonlinear optics, photoetching, micro-manufacturing and the like.

The invention relates to a solid laser with adjustable pulse width from a hundred picoseconds to a nanosecond and solves problems of complicated structure and high cost of a narrow-pulse-width large-energy laser structure obtained by means of a mode-locking technique in combination with amplification technology. Linear polarized light generated by a seed light laser successively passes an isolator, a shaper 1, a polarization device 1, an amplifier 1, and a polarization device 2 and then enters a SBS pulse compressor. Light returned from the SBS pulse compressor successively passes the polarization device 2, the amplifier 1, the polarization device 1, the shaper 2 and the amplifier 2 and then exits from amplifier 2. The solid laser is simple in structure, lower in cost compared with a product in the prior art, large in output energy, good in the quality of output light beams, and suitable for the fields of laser medicine, nonlinear optics, precision machining and laser communication.

The invention relates to a silver, gold nano particle distributed silicon dioxide optical thin-film and a preparation method thereof, belonging to the field of metal nano particle and inorganic non-metallic composite material. In the invention, the method of sol-gel is adopted to prepare simple substance metal nano particle distributed silicon dioxide Ag<x>Au<y> / (SiO2)<1-x-y> composite thin-film, the materials are ethyl orthosilicate, silver nitrate, chloroauric acid, absolute ethyl alcohol and distilled water; the preparation steps are as follows: configuring Aga<> / (SiO2)<1-a>, Aub / (SiO2)<1-b> sol with mol fraction a ranging from 0.02-0.9, mol fraction b ranging from 0.02 to 0.83; adopting a spin coater to coat Aga<> / (SiO2)<1-a>, Aub<> / (SiO2)<1-b> film on a glass substrate in an alternating way to prepare silver, gold single substance metal particle distributed sull thin film with a laminated structure. The method has the advantages that in the process of preparing the silver, gold single substance metal particle distributed sull, stoichiometric proportion of the Ag<x>Auy<> / (SiO2)<1-x-y> thin film can be accurately controlled, silver and gold both exist in the form of single substance, two absorption peaks can be observed within specific range of wavelength, light absorption scope is expanded and fine nonlinear optical characteristics are provided.

The invention relates to a POSS (Polyhedral Oligomeric Silsesquioxane) hybridized squarine near-infrared absorption dye, which at least comprises a POSS monomer of an active group and a halogenated squarine monomer. A preparation method of the dye comprises the following steps: in the nitrogen gas atmosphere, adding the POSS monomer and the halogenated squarine monomer in a mixed system of a catalyst, an acid-binding agent, a ligand and organic solvent; and carrying out an addition or polymerization reaction at the temperature of 130-140DEG C for 10-25h to obtain the POSS hybridized squarine near-infrared absorption dye. The POSS hybridized squarine near-infrared absorption dye has the advantages of stronger near-infrared absorbing performance, favorable heat, light and chemical stability and favorable aggregation resistance and material compatibility. The preparation method is simple and feasible, has favorable economic benefit, is applicable for industrial production and can be widely applied to the fields of nonlinear optics, photodynamic therapy, optical data storage, laser printing, biological probe, near-infrared photographing, solar cells and the like.