79 results about "Nano grating" patented technology

The compact reconfigurable polarization converter is characterized in that the compact reconfigurable polarization converter comprises a ridge-type silicon waveguide, and the upper surface of the ridge part of the ridge-type silicon waveguide is provided with a periodic sub-wavelength nano grating structure which is used for regulating and controlling the effective refractive index of transverse electric wave and transverse magnetic wave modes and has an inclination angle; the nanometer grating structure is made of Sb2Sb3 or Sb2S3 phase change materials, the nanometer grating structure is composed of a plurality of nanometer antennas which are the same in size and shape and parallel to one another, gaps of the nanometer grating structure are filled with SiO2 materials, an Al2O layer and a graphene heating layer are sequentially arranged on the upper surface of the nanometer grating structure and the upper surface of the SiO2 filling materials from bottom to top, and the graphene heating layer is arranged on the lower surface of the nanometer grating structure. And metal electrode palladium gold is arranged on the upper surface of the graphene heating layer and located on the two sides of the flat plate part of the ridge-type silicon waveguide. The device has the advantages that the function is reconfigurable, the size is smaller, the broadband is wider, and the power consumption is lower.

The invention belongs to the technical field of solar cells, and discloses a GaAs solar cell back surface photon structure based on a regenerated silicon wafer template and a preparation method. The method comprises the following steps: 1) carrying out ozone oxidation treatment on a regenerated silicon wafer; forming an oxide layer on the micron-sized textured surface of the regenerated silicon wafer; 2) inclining the processed silicon wafer, then carrying out geometric constraint etching, and generating a periodic gradient Bragg reflection nano grating on the micron-sized suede surface of the silicon wafer; 3) carrying out transfer printing and gas etching on the micron-sized textured surface and the nano grating structure of the silicon wafer on the back surface of the GaAs substrate, and forming micron scattering pits on the back surface of the GaAs substrate; and 4) preparing a back electrode on the back surface of the GaAs substrate with the micron scattering pits, and preparing a positive electrode on the front surface of the GaAs cell. The method is simple, template preparation energy consumption is reduced, atomic-scale conformal combination of the Bragg reflection array and the micron scattering substrate is achieved, and the obtained photon reflection structure has high efficiency and low optical loss.

The invention discloses a surface micro-nano structured graphene supercapacitor based on femtosecond laser processing and a preparation method thereof, a surface micro-nano structured graphene interdigital electrode is processed by femtosecond laser, and the surface of the surface micro-nano structured graphene interdigital electrode is provided with a periodic grating micro-nano structure parallel to the interdigital long axis direction; the supercapacitor with the periodic micro-nano grating structure parallel to the interdigital electrode direction is beneficial to increasing the specific surface area, provides more active sites, and can regulate and control the electric field to improve the migration rate of electrolyte ions. According to the supercapacitor with the periodic micro-nano grating structure parallel to the direction of the interdigital electrode, compared with a supercapacitor with the micro-nano grating structure perpendicular to the direction of the interdigital electrode and a supercapacitor without a micro-nano structure, the electrochemical performance of the supercapacitor is improved. A large-area supercapacitor array can be prepared based on the method, and the method has wide application potential in the fields of portable electronic equipment, intelligent wearable equipment, energy storage systems and the like.

The application discloses a micro-nano grating and photocathode collaborative design method. The method breaks the traditional isolated design, and considers the micro-nano grating and the photocathode as an organic whole, and takes the spectral response or integral quantum efficiency of the system as a whole as a target function. Specifically, the method comprises the following steps: establishing a system structure model and clearly defining an optimization target and process constraints; establishing a complex refractive index-wavelength correlation model of the photocathode to accurately obtain a complex refractive index distribution; determining a set of parameters to be optimized and setting initial values; calculating the system electric field distribution under the current parameters based on an electromagnetic simulation model; combining the electric field distribution and the photoelectric emission mechanism to calculate the spectral response of the system in the target waveband; and using a parameter optimization algorithm to iteratively search the parameter space, and outputting an optimal parameter combination. The application fully considers the electromagnetic and photoelectric coupling between the two and the actual process constraints, has the advantages of high design accuracy, strong pertinence, good implementability and the like, and can significantly improve the detection sensitivity of a weak light detection device.

The embodiment of the invention relates to the technical field of photoelectric detection, in particular to a laser-induced periodic structure enhanced photoelectric detector and a preparation method thereof, and the photoelectric detector comprises a substrate layer, a grating template layer, a bottom surface metal layer, a semiconductor layer and a surface metal layer from bottom to top; injection light is injected into the surface metal layer, surface plasmon polariton resonance is excited due to the nano grating structure of the surface metal layer, the absorption efficiency of the injection light is improved, and a wrinkle-shaped nano grating structure is arranged among the bottom surface metal layer, the semiconductor layer and the surface metal layer; the bottom surface metal layer, the semiconductor layer and the surface metal layer form a Fabry-Perot cavity structure, and after injected light enters a cavity, standing waves are formed in the cavity and interact with a material to generate an intra-cavity resonance enhancement effect; by adjusting the period of the grating structure of the grating template layer and the thickness of the semiconductor layer, multi-wavelength selection of the photoelectric detector can be realized. The photoelectric detector is simple and convenient to prepare, can be flexibly regulated and controlled and is suitable for batch production.

The present invention belongs to the technical field of displacement sensors, and specifically relates to a displacement sensor based on grating reflection and a four-step reflector, comprising a light source, a semi-transparent and semi-reflective mirror, a one-dimensional grating, a step reflector, and a four-quadrant detector, wherein the semi-transparent and semi-reflective mirror is arranged in the light path direction of the light source, the one-dimensional grating is arranged in the light path direction of the semi-transparent and semi-reflective mirror, the step reflector is arranged in the light path direction of the one-dimensional grating, and the four-quadrant detector is arranged in the reflected light path of the semi-transparent and semi-reflective mirror. The present invention utilizes the self-imaging effect of the nano-grating to detect the change in the output light intensity of the semi-transparent and semi-reflective mirror to realize the output of the A and B phase optical signals of the optical signal, thereby reducing the difficulty of electrical subdivision and realizing high-sensitivity displacement measurement. In addition, the present invention does not require auxiliary optical elements such as polarizers and half-wave plates, which significantly simplifies the measurement structure, reduces the cost of the device, and is conducive to the realization of structural miniaturization and integrated application.

The invention discloses a cuff-free blood pressure continuous monitoring method and system based on a light guide film, multiband reflected light signals of fingertip skin are collected through the light guide film attached to a terminal screen, the light guide film realizes directional light guide and stray light filtering through a micro-nano grating array, the light guide film is aligned with screen pixel hardware, and the light guide film is connected with the terminal screen. And the signal to noise is obviously improved compared with a common camera scheme. According to the method, multi-dimensional features such as time difference, rise time and enhancement index between dual-band pulse wave crests are extracted, and systolic pressure and diastolic pressure are calculated in combination with a user personalized baseline model. The system supports dual modes of active measurement and night passive monitoring, motion artifacts are eliminated through an acceleration sensor, ambient light interference is inhibited through an ambient light sensor, and one-machine multi-person exclusive monitoring, local encrypted data storage and user autonomous management are realized through linkage with an applicant spectrum identity recognition patent. The blood pressure monitoring device does not need cuff inflation, does not need electrocardio reference, is free of oppression, can realize non-perception continuous blood pressure monitoring when a user uses a mobile phone daily, and has the advantages of being non-invasive, continuous, low in cost, high in precision and safe in privacy.

The invention provides a personalized ear mold 3D printing technology and an application system thereof. The personalized ear mold 3D printing technology comprises the following printing steps: S1, synchronously acquiring multi-modal data: synchronously finishing by using an intelligent ear canal scanner: (1) physiological data: detecting a high-precision ear canal 3D model and a soft tissue elasticity modulus; according to the 3D ear mold printing technology, a non-European acoustic waveguide structure is optimized through multi-modal data fusion and a quantum annealing algorithm, millimeter-level anatomical matching and dynamic acoustic impedance tuning of the ear canal are achieved, and the acoustic impedance spectrum and the personalized frequency response preference of the ear canal of a user are obtained. According to the invention, femtosecond laser coloring is combined to construct a nano grating color developing layer and StyleGAN3 to generate microvascular bionic textures, so that the traditional single adaptive dimension is broken through, the ear mold has the lifelong evolution ability of acoustic self-adaption, aesthetic self-matching and physiological self-optimization, and a static hearing aid device is upgraded to an intelligent biological function extension body.

A metalens with a hybrid surface topology that includes a collection of nanopillars and a collection of nanogratings.

The present invention relates to the field of micro-nano optical technology, and in particular to a method and system for analyzing micro-nano grating device data for optical sensing. If one or more actual spectral characteristic data of a target micro-nano grating device exhibit baseline drift, the actual spectral characteristic data exhibiting baseline drift is defined as baseline drift spectral characteristic data; a correlation spectral control unit for the baseline drift spectral characteristic data is determined by querying a database based on the correlation spectral control unit; various real-time operating parameters of the correlation spectral control unit for the baseline drift spectral characteristic data are obtained, and parameter analysis and processing are performed on the various real-time operating parameters of the correlation spectral control unit for the baseline drift spectral characteristic data. This method not only improves the measurement accuracy of micro-nano grating devices in complex environments, but also enhances their stability and adaptability, and is of great significance for improving the overall performance of optical sensing systems.

A thermal diode includes: a dielectric enclosure having a top surface, a bottom surface, a first side, and a second side; a first Weyl semimetal nanoparticle disposed on the first side; a second Weyl semimetal nanoparticle disposed on the second side; a nanograting disposed on the bottom surface; and a voltage source configured to provide a voltage bias to the nanograting to suppress surface waves from the first Weyl semimetal nanoparticle to the second Weyl semimetal nanoparticle and to modify surface waves from the second Weyl semimetal nanoparticle to the first Weyl semimetal nanoparticle.

The invention provides a micro light-emitting structure, a micro light-emitting device and a preparation method of the micro light-emitting structure. The miniature light-emitting structure comprises a plurality of light-emitting units, and each light-emitting unit comprises a first semiconductor layer, a light-emitting layer and a second semiconductor layer which are stacked; the plurality of nano grating units are arranged in an array, the plurality of nano grating units are arranged on the side, away from the light emitting layer, of the first semiconductor layer, and the grating period between every two adjacent nano grating units is smaller than the wavelength of light emitted by the light emitting unit; each nano grating unit comprises a plurality of first grating layers and second grating layers which are alternately stacked in the direction away from the first semiconductor layer, the first grating layer is arranged at one end, facing the first semiconductor layer, of each nano grating unit, and the first grating layers and the second grating layers are made of non-metal dielectric materials; the refractive index of the first grating layer is smaller than that of the second grating layer.

The invention discloses a narrow-band filter based on a micro-nano grating, a spectrum chip and an imaging method, and belongs to the field of optical filters, the narrow-band filter comprises a dielectric layer, a metal grating layer and a substrate which are sequentially stacked from top to bottom, the dielectric layer covers the top of the metal grating layer and is wrapped between metal grating lines of the metal grating layer, and the metal grating layer covers the substrate. The thickness of the dielectric layer is 3000nm, the thickness of the metal grating layer is 40nm, and the distance between adjacent metal grating lines of the metal grating layer is 120nm; metal grating lines of the metal grating layer form periodic structures according to a periodic rule, one periodic structure forms a channel with one filter unit corresponding to one specific wavelength, multi-band spectral information is separated by selectively transmitting light with the specific wavelength, and all the periodic structures jointly form a narrow-band filter array. According to the invention, an artificial microstructure is adopted to realize a pixel-level light splitting effect, and the volume of a hyperspectral imaging system can be obviously reduced.

The invention relates to the technical field of anti-counterfeiting, and discloses an anti-counterfeiting rubber cap based on a micro-nano optical structure and a preparation method thereof.The anti-counterfeiting rubber cap comprises an anti-counterfeiting rubber cap body, a plurality of bright lines are arranged on the outer side of the anti-counterfeiting rubber cap body, dark lines are arranged on the anti-counterfeiting rubber cap body located between every two adjacent bright lines, and a code spraying area is further arranged on the outer side of the anti-counterfeiting rubber cap body; a plurality of separation lines are arranged at the top of the anti-fake rubber cap, an anti-fake chip is fixedly connected to the center of the top of the anti-fake rubber cap, and a plurality of verification points are arranged at the positions, close to the separation lines, of the top of the anti-fake rubber cap. Multiple anti-counterfeiting structures such as bright fringes, dark fringes, a code spraying area and an anti-counterfeiting chip are integrated, a multi-dimensional anti-counterfeiting system is formed, the imitation difficulty is greatly improved, a multi-layer interference optical variable structure of the bright fringes presents specific color value changes along with the visual angle, and the identification degree is high; due to the design of the micro-nano grating with dark fringes, exclusive patterns with high diffraction efficiency can be generated through laser irradiation, and the anti-counterfeiting reliability is enhanced.

The invention belongs to the technical field of perovskite light-emitting devices, and particularly discloses a method for preparing a perovskite light-emitting device by utilizing a transfer printing hole transport layer, which comprises the following steps of: preparing a glass substrate; preparing a photoresist grating template; a polydimethylsiloxane grating template is prepared; preparing medicines required for preparing the perovskite light-emitting diode device; spin-coating a hole transport layer; a micro-nano grating is introduced into the transfer printing hole transport layer; spin-coating a perovskite precursor solution; and 2, 2 ', 2' '-(1, 3, 5-triyl)-tri (1-phenyl-1-H-benzimidazole), lithium fluoride and aluminum are evaporated by adopting a vacuum thermal evaporation system. According to the method for preparing the perovskite light-emitting device by using the transfer printing hole transport layer, the micro-nano structured metal electrode and the organic material interface effectively excite the SPPs mode to be coupled into light energy to be emitted from the device, the energy loss of the SPPs mode is reduced, and the light extraction efficiency of the device is improved.

The application discloses a kind of micro-nano grating diffraction angle measurement system and measurement method, comprising: multi-frequency laser module, grating fixture module, light beam shrinkage module, light spot detection module, light spot imaging analysis module, electric control translation stage module.This method is by the wavelength control of laser emission light, excites the diffraction spot under different light beams;Through light beam shrinkage module shrinkage, again the light beam after shrinkage is transmitted to light spot detector module and is measured to the diffraction angle, solves the problem that the diffraction angle is too large, and the detection area of detector cannot cover all diffraction spots.In general, by the device and method, the direct measurement reading of the diffraction angle of micro-nano grating under different incident wavelengths can be realized, compared with traditional measurement method, with the advantages of simple operation, high measurement accuracy, large measurement angle range, etc., and the relative energy distribution of diffraction spot, light spot shape, relative position between light spots and other information can be imaged and recorded.

The invention relates to the technical field of anti-counterfeiting, and discloses a titanium substrate nano iridescent anti-counterfeiting structural color and a composite laser processing method and application thereof, and the method comprises the following steps: providing a titanium metal substrate; the titanium metal substrate is pretreated through a wide-pulse-width laser light source, so that a self-flowing layer is formed on the surface of the titanium metal substrate; and an ultrafast laser light source is adopted to carry out scanning processing on the titanium metal substrate on which the self-flowing layer is formed according to the anti-counterfeiting encryption icon, a nano grating structure capable of extracting a period is induced, and the titanium substrate nano iridescent anti-counterfeiting structural color is obtained. According to the technical scheme provided by the invention, the quality and environmental friendliness of anti-counterfeiting iridescent structural color processing can be ensured.

This invention discloses a photovoltaic glass based on polarization-sensitive characteristics for capturing sunlight and its preparation method, belonging to the field of building-integrated photovoltaics (BIPV) technology. It solves the technical problems of existing photovoltaic glass, such as small light-collecting area, poor visual effect, mutual constraints between light transmittance and power generation efficiency, and installation being severely limited by solar temporal variations. The nanograting structure prepared by this invention possesses polarization-sensitive properties that effectively enhance light absorption, removing the limitation of solar temporal variations on installation tilt angle, thereby reducing installation costs and increasing building power generation. Simultaneously, by optimizing the grating period, spacing, and height, the light transmittance / power generation ratio in the photovoltaic glass can be adjusted, meeting different user needs at a lower cost. The excellent energy-saving effect (good light-collecting effect, high power generation), low installation cost, and high economic applicability of this structure make it promising for applications in photovoltaic curtain walls, photovoltaic windows, photovoltaic roofs, and other building fields.

The invention discloses an ultraviolet scraping printing device and method.The scraping printing device comprises an unwinding shaft, a coating device, a mold scraping printing device, a plane rolling shaft, an ultraviolet curing device and a winding shaft, and continuous feeding of a polymer substrate is achieved through the winding and unwinding shaft; a coating device is used for coating the surface of the substrate material with the UV colloid with the specified thickness; under the condition that the edges of the die scraping and printing device do not make contact with a base material, the micro-nano grating structure is carved on the UV colloid, abrasion of the die is effectively avoided, and the size and shape of the die are determined by the grating die structure; curing the UV colloid with the micro-nano structure after flowing through the grating mold by using an ultraviolet curing device, keeping the micro-nano structure morphology, and conveying the UV colloid to a rolling shaft; a servo motor is used for accurately adjusting the distance between the grating mold and the substrate; adjusting the tension of the roller to ensure that the substrate is straight; the mold scraping and printing device is connected with a force sensor, the contact condition of the mold and the substrate is judged through a force value, a contact gap is adjusted, and therefore the thickness of the UV colloid is controlled.

The invention discloses a machining method for controlling the height of a nano periodic structure through a tool movement track, and belongs to the technical field of micro-nano machining. According to the specific scheme, the machining method for controlling the height of the nanometer periodic structure through the tool motion trail comprises the following steps that firstly, according to a motion equation, under the condition that the machining period is fixed, different nanometer down-milling machining motion trails of a tool are obtained by regulating and controlling parameters RX, Rz and phi; step 2, calculating the forming amount of the processing material in each period by adopting a numerical calculation method, adjusting the sizes and the relationship of the three parameters, and controlling the size of the forming amount of the material; selecting a proper motion trail of the cutter according to the forming amount of the nano grating material; 3, under different parameter combinations, tool paths are different, according to the tool paths, driving signals are set, the nanometer grating structure is machined, and morphology measurement is carried out; and 4, carrying out quality evaluation on the morphology measurement result, determining the optimal geometric characteristics of the processing track, and establishing a functional equation for predicting the height of the nano grating structure. By means of the machining method, efficient and high-quality machining of the surface nanometer periodic structures with different heights can be achieved, and the application performance of the surface nanometer periodic structures is improved.

The invention relates to the technical field of micro-nano optics, in particular to a polarization beam splitter parameter tuning method and system based on a micro-nano grating, and the method comprises the steps: obtaining test optical characteristic parameters of a polarization beam splitter to be evaluated, and judging whether the parameter tuning needs to be carried out on the polarization beam splitter to be evaluated or not according to the test optical characteristic parameters and preset optical characteristic parameters; if parameter tuning needs to be carried out on the to-be-evaluated polarization beam splitter, to-be-tuned optical characteristic parameters of the to-be-tuned polarization beam splitter are acquired; determining singular structure characteristic parameters of the polarization beam splitter needing parameter tuning according to the optical characteristic parameters to be tuned; and carrying out optimization processing on the singular structure characteristic parameters of the polarization beam splitter needing parameter tuning. According to the invention, the parameter tuning efficiency of the polarization beam splitter is effectively improved, the structural factors influencing the performance are accurately positioned, and finally the optical performance of the polarization beam splitter is ensured to meet the preset requirements.

The invention provides a pixel polaroid array and a design method thereof and a polarization imaging device, and relates to the technical field of optics, the pixel polaroid array comprises a substrate and a metal nano grating array, the metal nano grating array is arranged on the upper surface of the substrate, the substrate is used for supporting the metal nano grating array, and the metal nano grating array is arranged on the upper surface of the substrate. The metal nano grating array is composed of a plurality of polarization units which are periodically arranged; the polarization unit is composed of a plurality of polarization subunits arranged in the polarization direction. The polarization subunit is composed of a nano grating array; the line width of the nano grating array in the 0-degree polarization subunit is equal to the line width of the nano grating array in the 90-degree polarization subunit, the line width of the nano grating array in the 45-degree polarization subunit is equal to the line width of the nano grating array in the 135-degree polarization subunit, and the size of the polarization subunits is the same as the pixel size of the integrated image sensor. According to the pixelated design method, the overall extinction ratio and uniformity of the pixel polaroid array are improved.

The invention belongs to the technical field of micro-nano optical processing, and particularly relates to a method and device for coloring the surface of a transparent medium, the colored transparent medium and a product. The method for coloring the surface of the transparent medium comprises the steps that cutting parameters are set, and a periodic micro-nano grating structure is machined on the surface of a metal mold through an elliptical vibration cutting technology; the cutting parameters comprise the cutting speed, the cutting depth and the vibration frequency; the micro-nano grating structure on the surface of the metal mold is copied to the surface of a transparent medium through a copying technology, and the micro-nano grating structure can generate at least one specific color in a spectrum on the surface of the transparent medium under reflected light or transmitted light; by changing the incident light angle and the observation angle, the color of the reflecting surface or the transmitting surface of the transparent medium is adjustable. Controllable non-coating coloring is achieved on the surface of the transparent medium through the method, and a new thought and method are provided for development of micro-nano machining, optical coloring and related fields.

The invention discloses a trusted digital human local secure storage system. The system comprises an anti-intrusion safe box, a quantum optical memory bank and a block chain mapping engine. The safe box is of a five-layer composite protection structure (shape memory alloy and tungsten carbide armor), and three-level self-destruction (inflaming retarding / laser ablation / aluminum hot melting destruction) is triggered when invasion is detected. And the quantum optical memory bank records the nano grating in a quartz glass medium through femtosecond laser, so that 1PB capacity and thousand-grade data storage are realized. The innovative points comprise: 1) a biological dynamic key technology, fusing fingerprints, irises and real-time vital signs to generate encryption factors; the method comprises the steps of (1) establishing a double-chain synchronization protocol, storing local encrypted data in a private chain and authenticating transaction hash in a public chain, and (3) establishing a federated disaster recovery mechanism, and realizing data regeneration through a Shamir algorithm and a multi-signature intelligent contract, the system achieves the IP68 protection level and the EMC Level 4 immunity, the data unrecoverable rate is 100%, and the method is suitable for family, enterprise and government level digital asset protection.

The application provides a micro-nano grating structure optical topography coordinated feedback preparation method, comprising the following steps: rounding off the grating period and duty cycle based on the pixel size of a laser direct writing device, and eliminating the design end quantization error; establishing a proxy model of the structure parameters to the zero-level transmittance and the +1 and-1 order diffraction efficiency through parameter scanning and strict electromagnetic field theory calculation; performing line topography characterization simulation including proximity effect, development and etching on the design meeting the functional positioning, quantitatively extracting the period error, line width error, height error and surface roughness; feeding the topography error to the proxy model for iterative optimization, taking the minimum optical performance deviation as the target to iteratively pre-compensate the design parameters until convergence; and outputting a mask file and process guidance parameters to execute one-time preparation of the micro-nano grating. The application introduces the process topography error as a feedback quantity into the design optimization closed loop, realizes active compensation of the design to the process deviation before preparation, and significantly improves the first-time preparation success rate of the micro-nano grating.

The present application relates to a kind of silicon carbide diffraction optical waveguide structures and preparation method, the silicon carbide diffraction optical waveguide structure includes: high refractive index semi-insulating silicon carbide substrate, form on the surface of the substrate and have specific angle of inclination inclined grating, and the anti-reflection film covered in the top of the grating.This structure uses the high refractive index of silicon carbide material to realize the light transmission of ultra-thin, large field angle, concentrate diffraction energy by inclined grating design, and interface reflection loss is inhibited by means of anti-reflection film, and the comprehensive promotion of optical efficiency and imaging quality.The present application also discloses the preparation method of the above structure, and the micro-nano grating structure is accurately processed on the silicon carbide substrate by photoetching, pattern transfer and inclined etching process.The waveguide structure of the present application is suitable for high-performance augmented reality (AR) display and optical sensing system.

The invention relates to the technical field of semiconductor laser devices, in particular to a high-power-density distributed feedback type laser chip and a preparation process thereof. According to the technical scheme, the chip comprises a chip body, the chip body comprises a back electrode, a substrate, a lower waveguide layer, a lower limiting layer, an active layer, an upper limiting layer, an upper waveguide layer, a highly-doped layer and a front electrode which are sequentially stacked from bottom to top, and graphene layers are arranged on the sides, close to the active layer, of the lower limiting layer and the upper limiting layer. According to the invention, the graphene heat conduction layer and the conical bulge and micropore array are introduced between the active layer and the limiting layer, so that heat is directly and quickly dredged, thermal resistance and interface strain are reduced, heat accumulation is relieved from the source, and the reliability of the chip is improved; the artificial micro-nano grating formed by the conical structure and the DFB built-in grating cooperatively enhance longitudinal mode feedback, and improve the side mode rejection ratio and the light field limiting factor. Meanwhile, mode locking and 1 microsecond-level wavelength tuning are achieved through array type current injection, and the light spot and coupling efficiency is improved in cooperation with a unit-level micro lens.

The application discloses a grating diffraction efficiency detection system and a detection method thereof, which comprises a bearing platform, a sample platform rotatably arranged above the bearing platform, an incident assembly, a lens assembly, a first imaging lens, a beam splitter, a first photoelectric detection device, a second photoelectric detection device and a second imaging lens. The incident assembly comprises a light source aligned with the sample platform, a beam modulator arranged on an outgoing light path of the light source and a polarization modulator arranged on an outgoing light path of the beam modulator. The lens assembly is aligned with a micro-nano grating to be detected and a diffraction beam thereof. The first imaging lens is arranged on an outgoing light path of the lens assembly. The beam splitter is arranged on an outgoing light path of the first imaging lens. The first photoelectric detection device is arranged on a reflected light path of the beam splitter. The second imaging lens is arranged on a transmitted light path of the beam splitter. The second photoelectric detection device is arranged on an outgoing light path of the second imaging lens. The application solves the problem that a traditional macroscopic grating diffraction efficiency measurement scheme cannot detect the diffraction efficiency of a micro-nano scale diffraction grating.

The application relates to a 2D / 3D switchable stereoscopic display device based on a binary nanometer grating, which comprises a polarization-controllable light source, a light collimator, a pixel array light modulator and a binary nanometer grating phase modulation plate; light emitted from the polarization-controllable light source is collimated through the light collimator, the collimated light emitted from the light collimator passes through the pixel array light modulator and enters the binary nanometer grating phase modulation plate; when TM light is turned on and TE light is turned off, the binary nanometer grating does not produce deflection to the TM light, the pixel array light modulator provides a plane image, and 2D display is realized; when TE light is turned on and TM light is turned off, the binary nanometer grating produces light deflection to the TE light, the phase of the TE light is controlled through the period, height and depth-width ratio of the binary nanometer grating, and then the deflection angle and convergence position of the light are controlled, and 3D display is realized. The device has a simple structure, a wide field of view angle of naked-eye 3D display, high brightness and simple and fast switching.

A method for preparing micro / nano structures with enhanced hydrophobicity using a combination of picosecond and femtosecond lasers is disclosed. The method involves pre-treating a TC4 titanium alloy substrate to obtain a clean and smooth surface; using a picosecond laser to ablate the surface of the TC4 titanium alloy substrate to prepare a periodically arranged array of micron-sized square truncated pyramids as a primary microstructure; selectively irradiating the top platform of the micron-sized square truncated pyramids with a femtosecond laser to induce the formation of a periodic nanograting structure as a secondary nanostructure, thereby forming a micro / nano composite structure; and finally, cleaning and drying to obtain a superhydrophobic TC4 titanium alloy surface with a micro / nano composite structure.