427 results about "Linear optics" patented technology

The invention belongs to the related technical field of lasers, and provides a high-power subnanosecond-nanosecond laser in order to solve the problems that the range adjustment and the application range of an existing laser are limited, and the structural stability needs to be improved. A modulation semiconductor seed source, an optical fiber pre-amplifier, a light beam isolation system, a high repetition frequency solid pre-amplifier, an acousto-optic modulator frequency reduction module and a multi-stage solid single-pass main amplifier are sequentially arranged along an optical path, continuous adjustable output of repetition frequency and pulse width is achieved, the adjustable range of the repetition frequency is 100 kHz to 1 MHz, the adjustable range of the pulse width is 100 ps to 10 ns, and the adjustable range of the pulse width is 100 ps to 10 ns. The laser power and the light beam quality are remarkably improved, and the method is suitable for the fields of high-precision micromachining, nonlinear optical research, medical cosmetology and the like.

The invention relates to the technical field of laser ranging, in particular to a high-precision real-time distance calculation method based on a double-optical-comb laser ranging system. The high-precision real-time distance calculation method based on the double-optical-comb laser ranging system comprises the following steps: generating a double-optical-comb laser signal: generating the double-optical-comb laser signal by using a nonlinear optical effect, and dividing the double-optical-comb laser signal into two beams of light through an optical element for transmitting and receiving respectively; and transmitting the light signal: transmitting the transmitted light beam to a target object through an optical fiber or a free space. According to the invention, by adopting the double-optical-comb laser signals and combining real-time calculation of phase difference and frequency information, the distance measurement precision is obviously improved, the measurement precision of a submillimeter level can be achieved, and meanwhile, through real-time signal processing and a dynamic feedback mechanism, measurement requirements under different environmental conditions can be rapidly adapted; the timeliness and accuracy of a measurement result are ensured, and the dynamic measurement requirement is met.

A nonlinear all optical machine learning system (NAOMLS) with nonlinear optical resonator-based continuous wave and / or spiking neurons (NORs) and linear optical components or layers (LOL) learns to implement target tasks after machine learning based direct and / or indirect inverse design and / or optimization of the NORs and / or optimization of the LOL. The inversely designed and / or optimized NORs and the optimized LOL collectively define learnable mapping functions between input lights and output lights of the NAOMLS to meet target objectives for target tasks. In some embodiments, the NORs are indirectly and inversely designed to meet inversely designed objectives in order to be integrated with the NAOMLS so that the NAOMLS can function properly to meet target objectives for target tasks. In some embodiments, the NORs are integrated directly with the NAOMLS and inversely designed and / or optimized with the LOL to directly meet target objectives for target tasks.

The invention discloses a non-linear optical structure with perfect phase matching and high second harmonic generation efficiency. The non-linear optical structure comprises a fundamental frequency wave resonance structure, a non-linear optical layer, a second harmonic reflection structure and a substrate, the fundamental frequency wave resonance structure is used for generating electromagnetic field local enhancement at an incident fundamental frequency wavelength and realizing a phase matching condition by optimizing electric field phase distribution; the nonlinear optical layer is used for frequency conversion from fundamental frequency waves to second harmonics and regulating and controlling harmonic radiation capability and phase regulation and control; the second harmonic reflection structure is used for controlling coupling-out of second harmonics; the rotary nonlinear optical layer can adjust the phase characteristic of the radiated second harmonic so as to realize perfect phase matching of a harmonic field; according to the nonlinear optical structure with perfect phase matching and high-efficiency second harmonic generation efficiency, accurate control of phase matching conditions is realized through reasonable optical film stacking and phase matching technologies, and high-efficiency coupling-out and utilization of second harmonics are ensured.

The invention discloses a Mini LED package test method and test equipment. The method comprises the following steps: performing light irradiation on Mini LED package by using a reverse light path tracking technology to obtain an interference pattern and determine a function sensitive area; injecting a quantum dot fluorescent marker into the functional sensitive area to carry out multispectral dynamic monitoring; performing surface plasma resonance spectrum scanning on the functional sensitive area to obtain surface plasma resonance response data; performing an acoustic stimulation test on the functional sensitive area according to the obtained data to obtain acoustic response data; and performing a compensation test by using the nonlinear optical material layer to obtain performance attenuation prediction data. According to the technical scheme, accurate detection and performance prediction of the miniature optical structure in Mini LED packaging are achieved, and potential early failure symptoms can be effectively recognized.

The invention relates to a nonlinear optical crystal structure, a preparation method thereof and optical equipment. The nonlinear optical crystal structure comprises a plurality of material layers which are stacked in the direction perpendicular to the two-dimensional plane of the material layers. Each material layer is of a crystal structure with y-weight rotational symmetry and has a predetermined crystal lattice direction in a direction parallel to a two-dimensional plane; a non-zero deflection angle is formed between the adjacent material layers, and the deflection angle is an included angle of the preset crystal lattice directions of the adjacent material layers; wherein y is 1, 2, 3, 4 or 6. According to the nonlinear optical crystal structure and the preparation method thereof, the rotational symmetry crystals are stacked, and nonlinear enhancement of second harmonics and even higher harmonics is achieved by controlling the deflection angle between the material layers. Compared with a traditional nonlinear metasurface scheme, the nonlinear optical crystal structure can achieve higher accuracy, higher operability and higher efficiency.

The invention relates to an optical element desensitization method based on thermal stability of a visual axis of a space optical camera, and relates to the technical field of space optical cameras, and the method comprises the following steps: establishing a visual axis stability optical sensitivity matrix; key optical elements are positioned and optimized; analyzing the surface performance of the optical element; and the visual axis error is calculated through complete machine thermal load simulation analysis. According to the optical element desensitization method based on the thermal stability of the optical axis of the space optical camera, the key optical element influencing the stability of the optical axis of the space optical camera is accurately positioned by establishing the linear optical model, targeted optimization is performed, and the efficiency is improved; an optical element influencing the stability of the visual axis is directly subjected to structural optimization, rigid body displacement constraints are integrated in an optimization model, the sensitivity of the optical element to thermal loads is reduced, and the stability of the visual axis of the whole machine is more effectively guaranteed.

The present invention addresses the problem of providing: a composition and a polymer compound which are each capable of suppressing aggregation of a dye that has a nonlinear optical effect in a nonlinear optical material, and exhibiting a higher electro-optic effect with respect to the absorbance after poling; a nonlinear optical element which is obtained using the composition; and an optical modulator which comprises the nonlinear optical element and operates on the basis of an electro-optic effect. The present invention pertains to a composition which contains a compound represented by formula (1) and a compound represented by formula (3), wherein the content of the compound represented by formula (3) is 0.0001 mol% to 25 mol% inclusive relative to the total content of the compound represented by formula (1) and the compound represented by formula (3).　(Definitions of groups are as set forth in the description.)

The invention provides a linear optical quantum amplifier based on coding in time modes, which comprises a first photon detector and a second photon detector in two time modes, and an input end beam splitter, a first beam splitter, a second beam splitter and an output end beam splitter, the first photon detector is used for detecting photons appearing in a first time window of the upper path, and the second photon detector is used for detecting photons appearing in a second time window of the lower path; the input end beam splitter and the output end beam splitter completely transmit photons emitted in a first time window and completely reflect photons emitted in a second time window at the same time, the first beam splitter completely reflects the photons emitted in the first time window and reflects the photons emitted in the second time window with the reflectivity of gamma, and the second beam splitter completely reflects the photons emitted in the second time window with the reflectivity of gamma. And the first beam splitter completely reflects the incident photons in the first time window and transmits the incident photons in the second time window by a transmission coefficient of 1-gamma, the second beam splitter completely reflects the incident photons in the second time window and reflects the incident photons in the first window by a reflectivity of gamma, and the first beam splitter transmits the incident photons in the first time window by a transmission coefficient of 1-gamma. The method is more concise, easy to operate and better in amplification effect, and a large number of sub-state amplification protocols are achieved.

The invention discloses a single-frequency pulse laser with high spectral purity. The single-frequency pulse laser comprises a pump light processing system, an active resonant cavity, a gain medium, a light pulse generating device and a nonlinear optical modulator, the gain medium is arranged on an emergent light path of an input mirror of the active resonant cavity; the optical pulse generating device and the nonlinear optical modulator are both placed in the active resonant cavity, the optical pulse generating device is used for adjusting the loss of the active resonant cavity so as to form pulsed light, and the nonlinear optical modulator is used for rapidly increasing the loss difference between different modes in the resonant cavity so as to generate high-spectral-purity single-frequency pulse laser; the nonlinear optical modulator comprises a nonlinear crystal, and the nonlinear crystal is arranged on an optical path between the gain medium and the output mirror of the active resonant cavity. According to the invention, the nonlinear crystal, the optical pulse generation device and the gain medium are utilized to enable a secondary mode to be rapidly annihilated within a short time, so that the single-frequency pulse laser output with high spectral purity is realized.

The invention relates to the technical field of equipment calibration, in particular to a fluorescence microscope metering calibration method and system.The detection end is connected with a host, the detection end is provided with a standard light source and a micropore array plate matched with the magnification times of an objective lens, the standard light source serves as the standard light source, and the host controls the luminous intensity of the host to be adjustable through an electric signal; by adopting the micropore array plate, the light source is in uniform light transmission, equal-scale and gradient dot matrix arrangement, and objective lens magnification, imaging uniformity, imaging linearity and optical linearity calibration are carried out in sequence, so that the system not only has traceability, reusability and controllability, but also is low in use cost and high in reliability; meanwhile, the magnification, the light uniformity, the imaging linearity and the optical linearity of the eyepiece of the measured fluorescence microscope are gradually calibrated, so that the accuracy and the reliability of measured data are ensured.

The invention relates to the technical field of laser, in particular to a neodymium-doped garnet activated medium continuous wave yellow laser which comprises an excitation source, a focusing system, a laser medium crystal, a nonlinear optical crystal and a laser resonant cavity. The laser medium crystal and the nonlinear optical crystal are positioned in the laser resonant cavity; the laser resonant cavity is composed of an input mirror and an output mirror, and one side of a mirror cavity is plated with a dielectric film of a corresponding wave band. Pump light emitted by an excitation source is collimated by a focusing system, then enters a laser resonant cavity through an input mirror and is incident on a laser medium crystal, the laser medium crystal absorbs pump energy to generate energy level transition, and electron-phonon coupling laser is generated; and after the electron-phonon coupled laser is subjected to frequency conversion through the nonlinear optical crystal, continuous wave yellow laser is output from one end of the output mirror. The device has the characteristics of simple structure, high working stability and high temperature adaptability.

The invention relates to a nonlinear optical crystal and crystal combined adhesive and a preparation method thereof. The nonlinear optical crystal and crystal combined adhesive comprises the following components in parts by weight: 40-70 parts of hydrogenated bisphenol A type acrylate monomer; 20 to 40 parts of a polyfunctional thiol compound; the core of the core-shell structure nanoparticles is ZrO2, the shell of the core-shell structure nanoparticles is SiO2, the particle size of the core is 20-50nm, and the thickness of a shell layer is 3-8nm; and 0.1 to 0.5 part of a coupling agent containing a phosphate group. Through accurate regulation and control of the ZrO2atSiO2 core-shell nanoparticles, the refractive index of the adhesive can be adjusted in a range of 1.65-2.10, and is highly matched with the refractive index 1.7-2.2 of nonlinear optical crystals such as KTP, BBO and LBO, so that the Fresnel loss of a bonding interface is reduced to be less than or equal to 0.5 dB / cm, the laser frequency conversion efficiency is remarkably improved, agglomeration is effectively inhibited by the core-shell structure of the nanoparticles, and the laser frequency conversion efficiency is improved. The light transmittance of a cured adhesive layer under common laser wavelengths such as 1064 nm, 532 nm and 355 nm is larger than or equal to 99.5%, the adhesive layer is suitable for a high-power laser system, by adding the quantum dot material, the refractive index matching of the specific wavelength can be further optimized, and the application scene is expanded.

Methods and systems are provided for performing an encoded n-qubit GHZ measurement on n encoded (logical) qubits using encoded Bell state measurements (E-BSMs). Each E-BSM comprises a plurality of dual-rail Bell state measurements (DR-BSMs) performed on pairs of dual-rail encoded photonic qubits (DR-qubits). Methods and systems for using encoded n-qubit GHZ measurements for fault-tolerant measurement-based quantum computation are also provided.

The invention discloses an ancient building brick wall reinforcing method based on three-dimensional scanning and data analysis, and particularly relates to the technical field of brick wall reinforcing. The internal structure of the brick wall is monitored through multi-frequency laser excitation, the interference degree of a heterogeneous repairing material on the integrity of a scanning signal is evaluated, and the influence of refraction and scattering of an optical signal on three-dimensional point cloud data is further analyzed. By constructing a local characteristic curve, the obstruction degree of the nonlinear optical effect on brick damage identification is evaluated. By analyzing the generalized spectral characteristics of the local characteristic curve and combining the refractive index of the repairing material and the energy conduction characteristics of the surface structure of the brick body, the error amplitude of the interface scattering anomaly on the measurement of the brick joint depth and the crack range is evaluated. And comprehensively analyzing the hindering degree of the nonlinear optical effect and the error amplitude of the interface scattering abnormity, evaluating the suitability of the brick body and the repairing material, and formulating a targeted reinforcing strategy to ensure the effectiveness and long-term stability of the reinforcing effect.

The invention relates to a super-continuum spectrum light source in the field of laser technology and non-linear optics, in particular to an EYDFA output high-power super-continuum spectrum light source based on the XPM effect, which has the advantages of better spectrum flatness and wider bandwidth. The enhanced cross phase modulation effect is utilized to effectively inhibit high-intensity cascade Raman peaks in the output super-continuum spectrum and enhance low-intensity short wave components, and the spectrum flatness of high-power super-continuum spectrum laser in the broadband range is effectively improved; according to the invention, the problem that the flatness and width of the spectrum are influenced by high-intensity cascade Raman peaks and low-intensity short-wave components existing in the super-continuum spectrum output by the optical fiber amplifier can be effectively solved, and high-power super-continuum spectrum output is realized.

The invention relates to the technical field of laser output, and discloses a dual-wavelength laser output system, which comprises a first laser used for generating laser of a first wavelength; the second laser is used for generating laser with a second wavelength; the edge computing node is configured at a position close to the first laser and the second laser and is responsible for performing real-time processing and analysis on the laser data of the first wavelength and the second wavelength; the distributed computing framework is used for fragmenting the laser data and distributing the fragmented laser data to a plurality of edge computing nodes for processing; and the nonlinear optical crystal is configured on the laser output path and is used for converting and synthesizing the laser of the first wavelength and the laser of the second wavelength. Multi-wavelength output is realized through double lasers and a nonlinear optical crystal, real-time data processing and fault detection are carried out by utilizing an edge computing node, efficient data processing, storage and flexible deployment are ensured through a distributed computing framework and a database, and the stability and accuracy of the system are improved.

The invention relates to application of biguanide carbonate or biguanide nitrate as a nonlinear optical crystal, in particular to application of the biguanide carbonate or the biguanide nitrate as the nonlinear optical crystal to realize ultraviolet frequency doubling laser output. Through experimental tests, the frequency-doubled effect of the biguanide nitrate powder is about 3.5 * KDP, and the ultraviolet cut-off edge is about 318nm; the frequency-doubled effect of the biguanide carbonate powder is about 5 * KDP, the ultraviolet cutoff edge is about 258 nm, and compared with the frequency-doubled effect of the guanidine phosphate which is 1.5 * KDP, the second-order nonlinear optical performance of the biguanide carbonate and the biguanide nitrate is greatly improved; the two crystals are stable in air and high in product purity, and compared with a layered growth habit of a potassium boron beryllium fluoride crystal, the growth speed is high, a large-size transparent single crystal is easy to grow, and the two crystals can be applied to an all-solid-state laser as ultraviolet and ultraviolet solar-blind nonlinear optical crystals.

The invention relates to a light supplement data determination method and device and computer equipment. The method is applied to a photoelectric monitoring system, the photoelectric monitoring system comprises a camera shooting pan-tilt and a light supplementing pan-tilt, the camera shooting pan-tilt and the light supplementing pan-tilt are driven independently, and the method comprises the steps that according to the linear optical relation between the camera shooting pan-tilt and a monitoring target, the camera shooting pan-tilt is controlled to monitor the monitoring target, and calibration camera shooting equipment parameters are obtained; according to each geometric azimuth angle in the calibration camera equipment parameters, controlling the attitude of the light supplement holder to adjust, and obtaining the attitude data of the light supplement equipment; by taking the pose data of the light supplementing equipment as a light supplementing constraint condition, performing light supplementing analysis on the light supplementing holder according to each view field analysis angle in the calibration camera equipment parameters to obtain optical parameters of the light supplementing equipment; and fusing the light supplementing equipment pose data and the light supplementing equipment optical parameters to obtain target camera shooting light supplementing data. By adopting the method, the imaging interference of the monitored target can be effectively reduced, and the monitoring effect is further improved.

The invention belongs to the technical field of photoelectric functional materials, and relates to a Dion-Jacobson type two-dimensional organic-inorganic hybrid chiral perovskite single crystal as well as a preparation method and application thereof. The chiral hybrid perovskite crystal is a non-centrosymmetric P212121 space group of an orthorhombic crystal system, and has the advantages of shortened inorganic interlayer spacing, eliminated interlayer Van der Waals gaps and excellent structural stability. The specific synthesis method comprises the following steps: completely dissolving the lead-based semiconductor in a haloid acid solution; adding chiral diamine organic molecules into the solution, and heating to completely dissolve the chiral diamine organic molecules; standing, and carrying out gradient cooling to room temperature to obtain millimeter-scale crystals; and after washing, putting into a vacuum drying oven for drying, so as to obtain the Dion-Jacobson type organic-inorganic hybrid chiral perovskite single crystal. The obtained single crystal has a non-centrosymmetric structure, shows strong chiral characteristics, and can be applied to the fields of circularly polarized photoelectric detectors, circularly polarized luminescence, light emitting diodes, displays, nonlinear optics and the like.

The disclosure is related to systems, assemblies, apparatus, and methods relating to a radiation source for generating broadband radiation. The radiation source comprises a photonic crystal surface emitting laser PCSEL configured to output radiation at a first wavelength. The radiation source also comprises a non-linear optical element arranged to receive the radiation output by the PCSEL. The non-linear optical element is configured to convert the first wavelength radiation from the PCSEL into broadband radiation to be output by the radiation source through non-linear effects.

The application provides a nonlinear optical effect generation method, relates to the field of optoelectronic technology, and comprises the following steps: fixing and placing a polar ion crystal as a nonlinear medium, the polar ion crystal being a diatomic crystal or a polyatomic crystal with an optical phonon mode; using a modulated terahertz wave to excite a stimulated phonon polariton in the nonlinear medium, so as to enhance the nonlinear efficiency of signal light incident on the nonlinear medium; and adjusting the polarization angle and the incident angle of the signal light and / or the modulated terahertz wave, so as to generate a nonlinear optical effect. The application is based on the characteristics of the interaction between light and matter modulated by the stimulated phonon polariton, and the nonlinear polarizability is greatly improved by using the stimulated phonon polariton, so that the weak light nonlinear effect of most wavelengths of light can be realized efficiently; and the nonlinear optical effect has the advantages of high refresh rate, wide spectral response, low threshold and low power consumption.

Obtaining corneal measurements for non-contact tonometry. Systems, devices, and methods for determining intraocular pressure (IOP) of an eye are provided. The system may include a pump configured to generate an air puff and a nozzle configured to direct the air puff along a first axis toward the eye. The system may further include a light source distal to the nozzle and oriented to emit a light beam along a second axis transverse to the first axis toward a first linear optical sensor. A first portion of the light beam illuminates an outer surface of the eye, and a second portion of the light beam passes through a front surface of the eye. The system may further include a first linear optical sensor positioned distal to the nozzle and configured to receive the second portion of the light beam.

This application discloses a method and device for fabricating a periodically polarized ultrathin lithium niobate / lithium tantalate device, belonging to the field of nonlinear optical device manufacturing. The method includes: fabricating and polarizing periodic electrodes on a provided ferroelectric crystal wafer to form a periodically polarized master wafer; bonding the master wafer to a carrier substrate using optical resin-assisted bonding or direct bonding to form a composite structure; thinning and polishing the side of the master wafer away from the carrier substrate to obtain an ultrathin periodically polarized crystal functional layer; and fabricating the structure of the ultrathin periodically polarized crystal functional layer to obtain a periodically polarized ultrathin lithium niobate / lithium tantalate device. This method avoids the inherent problems of high-voltage breakdown and poor domain quality in existing technologies when directly polarizing ultrathin crystals by placing the high-risk polarization step on a thick, stable wafer.

The present invention relates to the field of large-field-of-view scenes. Provided is a nonlinear optical large-field-of-view imaging system, comprising a light source system, a laser scanning system and a laser detection system, wherein the light source system is configured to emit laser; the laser scanning system comprises a focusing lens and a galvanometer, wherein the galvanometer is located between the focusing lens and a sample to be detected, the focusing lens is configured to focus the laser on said sample, and the galvanometer vibrates according to a preset scanning angle so as to realize scanning of a laser focus on said sample; and the laser detection system comprises a compound-eye collection structure and a detector, wherein the compound-eye collection structure comprises a plurality of individual lenses which are closely arranged, optical signals generated by said sample are incident on the compound-eye collection structure, and the detector is configured to detect the optical signals collected by the compound-eye collection structure. The present invention can expand a laser scanning imaging range, can ensure that a laser beam always propagates along the optical axis of the focusing lens, and can comprehensively collect signals excited across the entire scanning field of view, thereby improving the efficiency of large-field-of-view imaging and increasing the signal intensity.

A single-material-double-process parametric laser-wavelength converter includes a pump-laser source, a nonlinear optical material, a first optical reflective element, and a second optical reflective element. The pump-laser source is configured to emit a pump-laser pulse light. The nonlinear optical material receives the pump-laser pulse and generates a signal-laser pulse and a partially depleted pump-laser pulse through optical parametric amplification. The first optical reflective element is configured to reflect the signal-laser pulse back to the same nonlinear optical material. The second optical reflective element is configured to reflect the partially depleted pump-laser pulse back to the same nonlinear optical material. With an appropriate adjustment on the reflecting path lengths, the nonlinear optical material is configured to receive the temporally synchronized signal-laser pulse and the partially depleted pump-laser pulse to generate an idler output through difference frequency generation. Both optical parametric amplification and difference frequency generation occur in the same nonlinear optical material.

The invention provides a weak illuminometer calibration system and calibration method. The method specifically comprises the following steps: S1, determining a calibration coefficient of a measurement system; s2, calculating to obtain a corresponding illumination correction factor; and S3, calculating a standard micro-illuminance value of the calibrated illuminometer by combining the display value of the first luminosity detector, the calibration coefficient and the illuminance correction factor under the corresponding aperture, and obtaining a relative indication error of the calibrated illuminometer by comparing a response value Ex of the calibrated illuminometer with the standard micro-illuminance value. Based on a highly-integrated linear optical system, the problems that in a traditional mode, the calibration process is tedious and prone to being interfered by the environment, errors are transmitted step by step, and precision is insufficient due to light intensity attenuation are solved, efficient, high-precision and traceable calibration in a weak illumination interval is achieved, operation is easy and convenient, and cost is low.

The invention discloses a dual-wavelength frequency doubling regulation and control method based on a PPLN waveguide, and relates to the technical field of nonlinear optics. The method comprises the following steps: constructing a PPLN waveguide model, and determining a fundamental frequency light mode and a frequency doubling light mode; calculating effective refractive indexes of the fundamental frequency light and the frequency doubling light at respective wavelengths; the polarization period is calculated according to the effective refractive index, any target polarization period is fixed, the target polarization period is configured to correspond to two different working wavelengths at the same time, and therefore dual-wavelength frequency doubling light with a specific wave crest interval is generated at the output end of the waveguide; the wave crest interval is regulated and controlled by selecting different polarization periods; according to the invention, dynamic control of dual-wavelength frequency multiplication output is realized by changing the size of a polarization period; the single waveguide can complete various optical function design ideas, and has certain value for research in related fields such as multi-wavelength lasers and wavelength multiplexing communication.

The application relates to a fluorine-containing ferroelectric nematic liquid crystal molecule and application thereof, relates to the technical field of photoelectric materials, and solves the problem of low dielectric constant of traditional liquid crystal materials which restricts the application of the liquid crystal materials in photoelectric functional devices. The molecule adopts a unique non-chiral V-shaped configuration design, takes a benzene ring as a core skeleton, and realizes performance optimization through meta-connection of differentiated functional side chains. In the molecular structure design, a strong electron-withdrawing trifluoromethyl substituent is introduced into the benzene ring 2, 4 of one end of the side chain, the intermolecular interaction force is enhanced, and the long-range order of the material is maintained; the other end adopts an alkoxy flexible chain structure, which not only improves the solubility of the material, but also enhances the thermal stability. The raw material is easy to obtain, the preparation is simple, the fluorine-containing ferroelectric liquid crystal molecule is in a nematic phase, the dielectric constant can be as high as 1.4 x 10 4 (1 kHz), and has a wide ferroelectric nematic phase transition temperature, high polarization intensity and nonlinear optical response, and has important application value in the field of photoelectric functional materials.

This invention relates to a potassium hydroxyborate nonlinear optical crystal, its preparation method, and its applications. The crystal has the chemical formula K₂B₅O₈(OH), a molecular weight of 277.26, belongs to the orthorhombic crystal system, and has a space group of [missing information]. Pca 21, with unit cell parameters a=8.5523(8)Å, b=7.3326(7)Å, c=12.9739(10)Å, α=β=γ=90°, V=813.60(13)Å. 3 A nonlinear optical crystal composed of potassium hydroxyborate can be obtained using a mild hydrothermal (solvothermal) method through programmed or natural cooling. The frequency doubling effect of this crystal powder is approximately twice that of KDP (KH₂PO₄), and its ultraviolet cutoff edge is below 200 nm, making it suitable as a deep-ultraviolet nonlinear optical crystal. The crystal growth process offers advantages such as simple operation, low raw material toxicity, short growth cycle, low cost, and stable physicochemical properties. It has been widely applied in the fabrication of nonlinear optical devices such as frequency doubling generators, up- or down-frequency converters, or optical parametric oscillators.