44 results about "Lithium triborate" patented technology

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

The invention relates to an intracavity-frequency-doubling 532nm single-longitudinal-mode laser based on seed light injection. A resonance detection method is used for obtaining 1064nm single-frequency pulse laser for seed injection is obtained and 532nm single-longitudinal-mode pulse laser is obtained through intracavity frequency doubling. A laser resonant cavity is a U-shaped cavity. Two high-peak-power laser diodes (LD) are used for pumping laser crystals from an end surface, a high-precision thermoelectric cooler is used for controlling the temperature of the laser crystals and green light output is obtained through intracavity lithium triborate (LBO) frequency doubling. The intracavity-frequency-doubling 532nm single-longitudinal-mode laser based on seed light injection has the characteristics of high efficiency, high energy, conduction cooling, narrow line width, high frequency stability, compact structure and high working stability.

The invention relates to a non-linear optical crystal of iodic acid zinc potassium. The iodic acid zinc potassium has a chemical formula of K2Zn(IO3)4(H2O)2 and the molecular weight of 864.74 and belongs to a monoclinic system; and the iodic acid zinc potassium has a space group C2 and unit-cell parameters are as follows: a is equal to 13.936 (6), b is equal to 7.7609(18), alpha and gamma are both equal to 90 degrees, beta is 126.75(3) degrees and Z is 1. The iodic acid zinc potassium is prepared by using a hydrothermal method. The iodic acid zinc potassium (K2Zn(IO3)4(H2O)2) has excellent non-linear optical performance and the powder second harmonic generation (SHG) coefficient of the iodic acid zinc potassium is 2.3 times that of KDP (KH2PO4) and is equivalent to that of LBO (lithium triborate).

The invention discloses a preparation method of a nonlinear crystal lithium triborate crystal surface high-laser-damaged-threshold antireflection film. Aiming at high LBO crystal anisotropy and the damage mechanism of the antireflection film, the method includes the steps that the surface of an LBO crystal is plated with a SiO2 film through an IAD process, and the film with which the surface of the LBO crystal is plated through the IAD process carries out plating through a sol-gel method. The LBO antireflection film prepared through the method has excellent optical properties, the high damage threshold and good environmental stability, and can be compatible with existing substrate machining, cleaning and film preparation processes. The preparation method has the beneficial effects of being high in process repeatability, high in controllability, easy to popularize and the like, and has wide application prospects in the field of high-power laser films in future.

The invention discloses a femtosecond ultraviolet laser. The femtosecond ultraviolet laser is composed of an optically connected seed source, a pulse broadener, an optical amplifier, a pulse compression module and a third frequency multiplication module. The seed source is an all-fiber passive mode-locked seed source or a solid mode-locked seed source; The pulse broadener is an all-optical fiber broadener or a spatial light broadener; The optical amplifier is an optically connected multi-stage optical amplifier; The pulse compression module is a prism pair or a grating pair or a chirped volumeBragg grating (CVBG); The frequency tripling module sequentially comprises a 1 / 2 wave plate, a polarization beam splitting prism, a convex lens, a concave lens, a frequency doubling crystal, a frequency tripling crystal, an absorbing block and an ultraviolet window plate. The second harmonic generation crystal is a kind of phase-matched lithium triborate (LBO) crystal, and the third harmonic generation crystal is a kind of phase-matched lithium triborate (LBO) crystal. The back surface of the third harmonic generation crystal is not coated and cuts the Brewster angle Theta B 1 of ultravioletlight, and the front surface of the second harmonic generation crystal is not coated and cuts the Brewster angle Theta B 2 of infrared light. The femtosecond ultraviolet laser realized according to the invention has simple and stable structure, long service life and is suitable for generating high-power femtosecond ultraviolet light.

The invention relates to a growing device of a lithium triborate (LBO) crystal. The growing device comprises a crucible and a convex part which is arranged on the inner bottom of the crucible. The invention also relates to a growing method of the LBO crystal. Growth of the LBO crystal is carried out by adopting the growing device. The growing device provided by the invention is simple in structure, simple and convenient to manufacture, and low in cost. By adopting the growing device and the growing method provided by the invention, large-caliber flat LBO single crystal can be directly grown, the cutting difficulty of a crystal apparatus is reduced, the utilization rate of the crystal is obviously improved, the processing link is reduced, the growth period of the crystal is shortened, and the manufacturing cost is reduced.

The invention discloses a sheet micro-cavity near infrared seed light injection locking tunable intermediate infrared narrow line-width optical parameter amplifier which comprises main pump light, a seed light source, a sheet micro-cavity light optical parameter oscillator (amplifier) and a high-pass optical filter. The main pump light is a single-frequency nanosecond laser device with the wavelength of 1064 nm, and pump light can be outputted for integral systems by the main pump light; a seed light system comprises light beam shaping lens systems, and the main pump light with the wavelength of 1064 nm is subjected to frequency doubling by means of birefringence phase matching by the aid of lithium boric oxide crystals, namely LBO, so that the pump light with the wavelength of 1064 nm can be converted into a single-frequency seed pump light source with the wavelengths of 532 nm; an optical parameter amplification system comprises the single-frequency pump light source with the wavelength of 1064 nm, a beam combiner and nonlinear periodically poled crystals, and the seed light system is responsible for generating injection locking near infrared narrow line-width single-frequency seed light.

The invention relates to a lithium triborate crystal surface antireflective microstructure, which has antireflective effect on ultraviolet, visible and near-infrared light. The microstructure parameters include period, depth, duty cycle, etc. All units of the microstructure are cuboid, cylindrical, conical or truncated cone structures. The microstructure parameters and the shapes of all the unitsare determined by specific use wavelength. The surface antireflective microstructure provided by the invention can effectively improve the transmittance of lithium triborate crystals at specific wavelength, and has very wide transmission bandwidth, well satisfies the requirements of high transmittance and bandwidth, and has very important practical significance for high power laser systems.

The invention discloses a triple-frequency ultraviolet laser. The triple-frequency ultraviolet laser comprises a seed source, a laser amplifier and a triple-frequency module connected in an optical manner, the seed source is a gain switch picosecond seed source, the laser amplifier is an optically-connected multistage amplifier, the triple-frequency module comprises a focusing lens, a double-frequency crystal and a heating furnace thereof, a triple-frequency crystal and a heating furnace thereof, an ultraviolet light splitter, and a collimator in sequence on an optical path, the focusing lens, the double-frequency crystal and the heating furnace thereof, and the triple-frequency crystal and the heating furnace thereof are arranged in a coaxial manner, the double-frequency crystal is a LBO crystal with one-class phase match, and the triple-frequency crystal is a LBO crystal with two-class phase match. According to the triple-frequency ultraviolet laser, the repetition frequency of the generated seed light is adjustable, the pulse width is adjustable, the light is the picosecond-level single-mode linearly polarized light, the characteristics of ultraviolet laser and the seed light are consistent after amplification and triple frequency, the power can reach 35 W, and the efficiency reaches up to 50%.

The invention provides an air-cooled all-solid 526nm pulsed laser. A laser crystal is formed by connecting two neodymium-doped lithium yttrium fluoride crystals in series and has an air-cooled heat dissipation structure. In a laser resonator, a U-shaped cavity is adopted; two laser diodes working in a pulse mode are used for pumping Nd:YLiF4 crystals from an end face; 1053nm fundamental frequency pulsed light is generated under the action of an electro optical Q switch; and lithium triborate crystals are subjected to intracavity frequency doubling to generate 526nm pulsed green light which is output. The laser has the characteristics of compact structure, high output pulse energy and reliability and stability in operation.

A 473nm electro-optic q-switch laser comprises a local oscillator stage, an amplifier stage and an extracavity frequency doubling stage. A convex-concave cavity suitable for high-power laser output is adopted for a resonant cavity of the local oscillator stage, a double-end pulse pump is in bonding with a neodymium-doped yttrium aluminium garnet (Nd:YAG) crystal, an electro-optic q-switch generates 946nm fundamental frequency light, high-power 946nm laser is obtained through the amplifier stage, and 473nm blue light laser is generated by two lithium triborate (LBO) crystals placed in a cascade mode finally. The 473nm electro-optic q-switch laser has the advantages of being high in repetition frequency, narrow in pulse width, high in single pulse energy and good in light beam quality, and is suitable for underwater measurement of a high-precision laser radar.

The invention provides a Raman spectrum liquid detection method based on a linear intracavity frequency doubling and hollow-core fiber. According to the method, a continuous laser device with the wavelength of 915 nanometers or 976 nanometers is used as a light source and an annular laser resonant cavity is adopted, 532 nanometer laser with narrow linewidth is further obtained through an active fiber and a lithium boric oxide frequency doubling crystal, and liquid to be detected is stimulated to generate Raman scattering light; meanwhile, the liquid detection method provided by the invention has the advantages of few longitudinal modes, good coherence, compact structure, high frequency doubling efficiency, high reliability and the like.

Provided is a mixed positive electrode active material comprising a large-grain positive electrode active material with an average diameter of 10 μm or greater and a small-grain positive electrode active material with an average diameter of 5 μm or smaller, in which the large-grain positive electrode active material and the small-grain positive electrode active material are coated with different materials between lithium triborate and metal oxide, respectively.

The invention belongs to the technical field of crystal growth, and provides a method for synthesizing an LBO (Lithium Triborate) crystal growing raw material. The method comprises the following steps: adding Li2MoO4 and H3BO3 into deionized water of 100 DEG C to prepare a cream object, drying and grinding the cream object into powder to obtain a growing raw material, and further sintering to obtain a sintered body. The invention further provides a method for preparing an LBO crystal. The method comprises the following steps: putting the sintered body into a crystal growing furnace, raising the temperature till the sintered body is molten, stirring the solution, cooling the solution till the temperature is 5-10 DEG C higher than a saturation point temperature, so as to obtain a uniformly mixed melt, preheating a seed crystal, subsequently slowly introducing into the crystal growing furnace to enable the seed crystal to start to grow slowly at the cooling rate of 0.1 to 1 DEG / day when the seed crystal is neither molten nor grows after 24 h; after the crystal growth is accomplished, taking out the crystal from the melt, cooling down to be at the room temperature, and taking out so as to prepare the LBO crystal. According to the method, the reaction components are prevented from deviation at high temperature in solid phase synthesis, the grown LBO crystal is good in quality and free of crystal defect such as inclosure.

The invention provides a Raman spectrum liquid detection method based on laser frequency doubling and dual hollow-core fibers. A continuous laser with the wavelength of 915 or 976 nanometers is used as a light source, a laser resonant cavity comprising a first fiber Bragg grating and a second fiber Bragg grating is used, narrow-line-width 532 nanometer laser is further acquired by an active fiber and lithium triborate frequency doubling crystals, and reference liquid and liquid to be detected in the dual hollow-core fibers are respectively excited to generate Raman scattering light. Besides, the liquid detection method has the advantages of less longitudinal modes, good coherence, high measuring efficiency, high reliability and the like.

The invention provides a Raman spectrum liquid detection method based on frequency doubling and hollow-core optical fiber in a linear cavity. The method comprises the steps that a continuous laser with the wavelength being 915 nanometers or 976 nanometers is used as a light source, a linear resonant cavity formed by a fiber bragg grating and an optical fiber total-reflection mirror is adopted, narrow-linewidth 532 nano laser is obtained through an active optical fiber and a lithium boric oxide frequency doubling crystal, and to-be-detected liquid is excited to generate Raman scattering light; meanwhile, the liquid detection method has the advantages of adopting few longitudinal modes, being good in coherence, compact in structure, high in detection efficiency and reliability and the like.

The invention relates to nonlinear optical and ferroelectric crystals dimethylammonium germanium tetraborate, a preparation method and application thereof. A chemical formula of the crystals is [Ge(B4O9)].2CH3NH3; the molecular weight is 323.97; the crystals belong to a monoclinic system; the space group is C2; and unit cell parameters are that: a is 10.249(1), b is 9.449(1), alpha is equal to gamma which is 90 degrees, beta is 131.76(2) degrees, and Z is 2. The dimethylammonium germanium tetraborate is prepared by a solvothermal method. The dimethylammonium germanium tetraborate has excellent nonlinear optical and ferroelectric properties. The powder second harmonic generation (SHG) coefficient of the dimethylammonium germanium tetraborate is 2.0 times that of potassium dihydrogen phosphate (KDP) and is equivalent to that of lithium triborate (LBO). The remanent polarization strength is about 0.98mu C.cm<-2>, the coercive field is 22kV.cm<-1>, and the spontaneous polarization strength is 1.26mu C.cm<-2>.

A 473nm electro-optic q-switch laser comprises a local oscillator stage, an amplifier stage and an extracavity frequency doubling stage. A convex-concave cavity suitable for high-power laser output is adopted for a resonant cavity of the local oscillator stage, a double-end pulse pump is in bonding with a neodymium-doped yttrium aluminium garnet (Nd:YAG) crystal, an electro-optic q-switch generates 946nm fundamental frequency light, high-power 946nm laser is obtained through the amplifier stage, and 473nm blue light laser is generated by two lithium triborate (LBO) crystals placed in a cascade mode finally. The 473nm electro-optic q-switch laser has the advantages of being high in repetition frequency, narrow in pulse width, high in single pulse energy and good in light beam quality, and is suitable for underwater measurement of a high-precision laser radar.

A broad line red light generator is configured with a single mode (SM) pulsed ytterbium ('Yb') fiber laser pump source outputting pump light in a fundamental mode ('FM') at a pump wavelength which is selected from a 1030 - 1120 nm wavelength range. The disclosed generator further includes a SM fiber Raman converter spliced to an output of the Yb fiber laser pump source. The Raman converter induces an 'n' order frequency Stokes shift of the pump light to output the pump light at a Raman-shifted wavelength within 1220 and 1300 nm wavelength range with a broad spectral line of at least 10 nm. The disclosed light generator further has a single pass second harmonic generator ('SHG') with a lithium triborate ('LBO') nonlinear optical crystal having a spectral acceptance linewidth which is sufficient to cover the broad spectral line of the pump light. The SHG generates a SM pulsed broad-line red light with a broad spectral line of at least 4 nm.

The present invention aims to provide a thermoluminescent phosphor for obtaining a two-dimensional or three-dimensional dosimeter for measuring dose absorbed by biological tissues, the thermoluminescent phosphor exerting superior handleability, exhibiting superior biological tissue equivalence, and having superior precision.The aforementioned object is achieved by means of a method for producing a thermoluminescent phosphor, the method comprising a step A1 for mixing lithium tetraborate, boron oxide and manganese dioxide, a step A2 for firing the aforementioned mixture at 770 to 840° C., and a step A3 for obtaining the thermoluminescent phosphor comprising lithium triborate as a base material and manganese as a luminescent center present in the base material by further adding and mixing lithium tetraborate into the aforementioned fired product and then firing the mixture at 770 to 840° C., wherein the molar ratio between the lithium tetraborate and the boron oxide in the step A1 is 1:X (1<x≦4), the amount of the manganese dioxide is 0.02 to 1.0 mass % relative to the total mass of the boron oxide and the total amount of the lithium tetraborate added in the steps A1 and A3, and the amount of the lithium tetraborate in the step A3 is (X−1) mol relative to 1 mol of the boron oxide.

The invention provides a cross-polarization dual laser for green wave band and relates to the field of lasers. The laser adopts a Yb:YCaO(BO3)3 crystal as a laser gain medium; a semiconductor laser or other light sources is / are taken as a pumping source; an LBO (lithium triborate) with the non-critical phase matching angle is taken as a frequency multiplication material; and the green wave band dual laser output is obtained by the frequency multiplied Yb:YCaO(BO3)3 crystal cross-polarization dual lasers generated in a cavity and out of the cavity.

The invention relates to the design and manufacturing of a compact laser chip, which utilizes a 1.06-um fundamental frequency laser of a laser crystal Nd: YVO4, and obtains 0.53-um frequency doubling green light through frequency doubling of nonlinear crystal PPLN (periodically poled lithium niobate). The chip comprises a laser crystal Nd: YVO4, a nonlinear crystal PPLN [or potassium titanyl oxygenic phosphate (KTP), lithium triborate (LBO), periodically poled potassium titanyl oxygenic phosphate (PPKTP), periodically poled lithium tantalite (PPLT) and the like), heat sink Si or AIN, and a resonant cavity consisting of optical films plated on the surfaces of two crystals. The compact laser chip is characterized in that the laser crystal and the nonlinear crystal are welded (or glued) on the heat sinking through welding flux (glue) under the situation that two cavity surfaces are ensured to be parallel. The laser chip structure has a simple structural design, small volume, low cost, and convenience in mass production; and when the compact laser chip is used, a suitable semiconductor pumping source is matched so that the green light with specific wavelength can be output, and the compact laser chip is expected to be widely applied in laser display.

The invention provides a Raman spectral liquid detection method based on laser frequency doubling and hollow-core optical fibers. The method adopts a continuous laser device with the wavelength of 915 nm or 976 nm as a light source and adopts a laser resonant cavity composed of a first optical fiber Bragg grating and a second optical fiber Bragg grating, and furthermore, a narrow-line-width 532 nm laser is obtained through an active optical fiber and a lithium triborate frequency doubling crystal and a to-be-detected liquid is stimulated to generate Raman scattering light; at the same time, the liquid detection method also has the advantages of wide application range, high measuring efficiency, high reliability and the like.

The invention provides a Raman spectral liquid detection method based on laser frequency doubling and hollow-core optical fibers. The method adopts a continuous laser device with the wavelength of 915 nm or 976 nm as a light source and adopts a laser resonant cavity composed of a first optical fiber Bragg grating and a second optical fiber Bragg grating, and furthermore, a narrow-line-width 532 nm laser is obtained through an active optical fiber and a lithium triborate frequency doubling crystal and a to-be-detected liquid is stimulated to generate Raman scattering light; at the same time, the liquid detection method also has the advantages of wide application range, high measuring efficiency, high reliability and the like.

The invention provides a Raman spectrum liquid detection method based on a linear intracavity frequency doubling and hollow-core fiber. According to the method, a continuous laser device with the wavelength of 915 nanometers or 976 nanometers is used as a light source and an annular laser resonant cavity is adopted, 532 nanometer laser with narrow linewidth is further obtained through an active fiber and a lithium boric oxide frequency doubling crystal, and liquid to be detected is stimulated to generate Raman scattering light; meanwhile, the liquid detection method provided by the invention has the advantages of few longitudinal modes, good coherence, compact structure, high frequency doubling efficiency, high reliability and the like.

The embodiment of the specification provides a method for preparing a lithium triborate seed crystal, the method comprises the following steps: uniformly mixing raw materials according to a first mass ratio, wherein the raw materials comprise lithium carbonate and boric acid; putting the uniformly mixed raw materials into a pre-synthesis device for pre-synthesis operation to obtain pre-synthesized powder; grinding the pre-synthesized powder to a preset particle size; uniformly mixing the ground powder and a fluxing agent according to a second mass ratio; filling the uniformly mixed powder and fluxing agent into at least one first crucible; placing at least one first crucible in a second crucible; placing the second crucible in a heating device for melting operation, and obtaining a melt of the powder and the fluxing agent; and performing a melt-based seed crystal growth process through multiple temperature adjustment operations.