12results about How to "Increased Laser Damage Threshold" patented technology

The invention provides a flexible high-energy laser sensing film sensor. The flexible high-energy laser sensing film sensor comprises a sensing film and a laser high-reflection film layer on the surface of the sensing film. The sensing film is composed of a flexible substrate, an upper surface transition layer, a lower surface transition layer, an upper surface thermistor layer, a lower surface thermistor layer, an upper surface lead layer, a lower surface lead layer, an upper surface protection layer and a lower surface protection layer. The thin film type double-sided resistor array is used for monitoring the laser irradiation transient thermal effect in real time, the laser detection threshold value is increased in combination with the laser high-reflection film layer, and rapid and accurate measurement of laser irradiation parameters such as laser power density, light spot size and irradiation position can be achieved; the device solves the problem that the existing devices such as a laser power meter and a laser spot analyzer are limited in light sensing diameter and are difficult to be suitable for large-spot-size laser parameter measurement and laser sensing alarm, and has the advantages of flexibility, large area, simple structure, low cost and the like.

The invention relates to a device and a method for coupling a laser beam of a laser into a double-clad fiber, comprising a first birefringent optical element which is designed to divide the laser beam entering at a beam entry surface into two sub-laser beams, the two sub-laser beams have a first exit angle and / or a first beam offset relative to a beam exit surface normal; comprising a polarization rotation device configured to adjust the polarization of an incident sub-laser beam and thereby provide a polarization-adjusted sub-laser beam; comprising a second birefringent optical element, the second birefringent optical element being configured to divide each of the polarization-adjusted sub-laser beams into two sub-sub-laser beams, the two sub-sub laser beams have a second exit angle and / or a second beam offset with respect to the beam entry surface normal of the second birefringent optical element; and a coupling-in optical unit, which is designed to couple the sub-sub laser beams having the compensated first exit angle and / or beam offset into the inner core of the double-clad optical fiber and to couple the further sub-sub laser beams into the annular core of the double-clad optical fiber.

The invention relates to a nonlinear optical crystal of guanidinium tetrafluoroborate and a preparation method and use thereof. The crystal has a chemical formula of [C(NH2)3]BF4 and a molecular weight of 146.89. It belongs to the trigonal crystal system; its space group is R3m; its lattice parameters are a=7.4634(10)A, b=7.4634(10)Å, c=9.1216(19) (6)Å, and Z=3; its ultraviolet cutoff edge is 200 nm; and its frequency-multiplication response is 4-5 times of that of the commercialized nonlinear optical crystal KDP. In the invention, a hydrothermal method, a roomtemperature solution method, an evaporation method or a solvothermal method is used to grow the crystal in a centimeter-scaled size. The invention relates to use of the crystal in the preparation of producing frequency-doubling, frequency-tripling, frequency-quadrupling, frequency-quintupling or frequency-sextupling harmonic light output from the fundamental frequency light of 1064 nm generated by a Nd: YAG laser; or producing a ultraviolet and deep-ultraviolet frequency-multiplication light output below 200 nm; or in the manufacture of a frequency-multiplication generator, a frequency up or down converter or an optical parametric oscillator.

The present invention relates to a preparation method and use of a lithium niobium telluride compound and a nonlinear optical crystal thereof, wherein the chemical formula of the lithium niobium telluride compound is LiNbTeO5. Specifically, the lithium niobium telluride compound is a polycrystalline powder or a nonlinear optical crystal, and the lithium niobium telluride nonlinear optical crystal has a wide transmission range, a strong frequency doubling effect, a high laser damage threshold, stable physical and chemical properties, is not easy to deliquesce, and is easy to cut, polish and store.

The invention belongs to the technical field of high-power laser films, and relates to a high-threshold high-stability laser film for realizing base-film integration based on continuous gradual change of refractive index, the film structure is S / L1L2L3 / A, S represents a substrate, L1 represents a transition layer between the substrate and L2, L2 represents a function realization layer with continuous gradual change of refractive index, L3 represents an impedance adaptation layer between L2 and an incident medium, and A represents an impedance adaptation layer between L2 and an incident medium. A represents an incident medium. According to the base-film integrated intense laser thin film based on continuous gradual change of the refractive index, planarization treatment is carried out on defects of the base, a double-region co-sputtering preparation method is adopted for the L1 layer and the L2 layer, continuous gradual change of the refractive index from the base to an incident medium is achieved, and different optical function requirements are met. According to the integrated film, the problem of stress mismatching caused by thermal expansion coefficient difference between the substrate and the film layer and between different layers in the film layer is effectively solved, a sudden change interface between materials is eliminated, the jump characteristic of a discrete interface of a traditional film is avoided, and the laser damage threshold and stability of the film are improved.

The present application relates to optical film and its preparation method and application. The optical film comprises a substrate, a dielectric film and a nanostructure surface layer arranged in sequence, the material of the nanostructure surface layer is selected from fluorine-containing resin or nano-organic silicon, and the porosity of the nanostructure surface layer is 20%-91%; wherein the surface of the nanostructure surface layer away from the substrate has a concave-convex structure, in the convex part of the concave-convex structure, the maximum width of the bottom part close to the substrate is L1, the maximum width of the top part away from the substrate is L2, the height of the convex part is H, 1.1:1≤L1 / L2≤15:1, 1.5:1≤H / L1≤20:1. The optical film has wide spectrum, low reflectivity, low scattering and high laser damage threshold, and can effectively improve the shooting definition and laser damage resistance effect when used in optical devices.

The application belongs to the technical field of inorganic nonlinear optical materials, and particularly discloses a bismuth-based infrared nonlinear optical crystal, a preparation method and application thereof. The molecular formula of the optical crystal is RbBiP2S6, and the crystal structure belongs to a monoclinic system and a space group P21. The optical crystal has excellent second-order nonlinear optical properties, can realize phase matching in an infrared waveband, has a wide light transmission range, and has strong infrared frequency doubling response. The powder frequency doubling intensity of the optical crystal can reach 10-15 times of that of a commercial material AgGaS2, and the laser damage threshold of the optical crystal is 9-13 times of that of an AgGaS2 crystal. The optical crystal has important application value in high-tech fields such as laser frequency conversion, near-infrared probe and photorefractive information processing, and is particularly used for infrared detectors and infrared lasers.

The invention discloses high-transmittance self-cleaning coated glass and a preparation method thereof, and belongs to the technical field of functional glass. The components of the high-transmittance coating film comprise magnesium fluoride, titanium dioxide, zinc fluoride and zinc salt, magnesium fluoride, titanium dioxide and zinc fluoride have high refractive indexes, light reflection can be effectively reduced, when light is emitted into the glass from air, light can be reflected on the upper interface and the lower interface of the high-transmittance coating film, and the light transmittance is improved. The reflected light on the two interfaces is subjected to destructive interference, so that the intensity of the reflected light is reduced, the reduction of the reflected light means that the transmission light is increased, and the light transmission of the glass is improved. The micro-nano array is arranged on the surface of the coated glass, so that the light transmittance of the glass can be improved, the surface characteristics of the glass can be effectively improved, dust, organic pollutants and the like are automatically separated from the surface of the glass under the washing of rainwater, and the self-cleaning effect of the glass is improved.

The embodiment of the invention discloses a multi-node structure light field generation device with interactive network characteristics, which comprises a transparent substrate and a plurality of diffraction modulation units, the diffraction modulation units are at least three sheet-shaped fork-shaped gratings, and the number of the sheet-shaped fork-shaped gratings is larger than that of the transparent substrate. The sheet-shaped fork-shaped gratings are integrally inscribed on the surface of the transparent substrate through a laser direct writing technology, each sheet-shaped fork-shaped grating has an independent light field phase modulation function, and from the sheet-shaped fork-shaped grating inscribed for the first time, each sheet-shaped fork-shaped grating has an independent light field phase modulation function relative to the adjacent lower sheet-shaped fork-shaped grating from bottom to top; the sheet-shaped fork-shaped gratings rotate around a shaft in the same direction to generate a constant dislocation angle, the dislocation angle refers to the relative rotation angle between two adjacent sheet-shaped fork-shaped gratings, and the product of the number of the sheet-shaped fork-shaped gratings and the dislocation angle is smaller than or equal to 360 degrees. And the types and complexity of the generated light field are enriched.

The present invention provides a method and device for distributed detection of trace multi-component gas in optical fiber. The detection method includes: the gas to be measured freely diffuses into the core of a hollow-core optical fiber with holes drilled on the side; the pump light and the seed light are coupled into the optical fiber from opposite directions; the gas to be measured is excited by the pump light and the seed light to generate a second Raman gain signal, the pump light is sequentially excited at the interface fused silica at both ends of the hollow-core optical fiber to generate the first and third Raman gain signals, and the first, second and third stimulated Raman gain signals are detected; the time when the second Raman gain signal reaches the photodetector is measured to determine the position of the gas to be measured; the intensity of the second Raman gain signal is measured to obtain the distributed concentration of the gas to be measured along the length of the hollow-core optical fiber. The device includes: multiple seed lasers, an optical switch, a polarization controller, an isolator, a hollow-core antiresonant optical fiber with holes drilled on the side, a circulator, a pump light filter, a photodetector, a pump laser, and fused silica at the optical fiber interface.

A method for surface shape control of optical elements based on target-substrate eccentric deposition includes the following steps: First, select the coating material for the surface shape control layer, calculate the non-uniformity of the film thickness distribution of the coating material under different target-substrate eccentric angles, and determine the actual target-substrate eccentric angle for preparing the surface shape control layer; next, fit the calculated film thickness distribution of the surface shape control layer under the target-substrate eccentric angle to obtain the compensated surface shape power value achieved by the surface shape control layer within a certain deposition time; then, determine the actual deposition time for preparing the surface shape control layer based on the power value to be compensated for the optical element; finally, prepare the surface shape control layer using magnetron sputtering technology. This invention achieves surface shape control by adjusting the relative eccentricity angle between the target and the substrate during magnetron sputtering deposition, adapting to any surface shape optical element without modifying hardware and without affecting the element's optical performance; the thickness of the surface shape control layer is significantly reduced compared to traditional methods, which helps to improve the damage threshold of laser thin film elements.

The invention discloses a hafnium oxide magnetron sputtering film with a high damage threshold for high repetition frequency femtosecond laser. The invention discloses a preparation method of the hafnium oxide magnetron sputtering film with the high damage threshold for the high repetition frequency femtosecond laser. The preparation process comprises the following steps: 1, by taking fused quartz as a substrate, etching the fused quartz in a hydrofluoric acid buffer solution before coating, then immediately cleaning the substrate with acetone, ethanol and deionized water, and finally drying in a drying box; and 2, performing sputtering coating on the high-purity hafnium target material by adopting a radio frequency magnetron sputtering coating system, and regulating and controlling sputtering power and an oxygen / argon gas flow ratio in the sputtering process to obtain the hafnium dioxide film deposited on the fused quartz substrate. And 3, putting the film into an annealing furnace for high-temperature annealing to obtain the final hafnium dioxide film. The optical performance of the hafnium dioxide thin film is remarkably improved by combining pretreatment of the substrate, regulation and control of deposition parameters and treatment after annealing, and the hafnium dioxide thin film shows good transmissivity in an ultraviolet visible region and a high damage threshold value under high-repetition-frequency femtosecond laser irradiation and can be applied to the field of high-repetition-frequency femtosecond lasers.