109 results about "Surface grating" patented technology

The invention discloses a joint test system, a silicon carbide metasurface grating detection method and a silicon carbide metasurface grating detection device, and belongs to the technical field of semiconductor detection. A synergistic excitation signal is generated by regulating a light source and a microwave source and is applied to the silicon carbide metasurface grating to be measured to form a light intensity and microwave field interference pattern. The method comprises the following steps: synchronously acquiring data through multiple channels, constructing a multi-dimensional matrix through time alignment, marker feature extraction and coordinate mapping, extracting defect features to establish a reference model, calculating deviation degree to judge quality, and carrying out abnormal point screening, candidate region construction and coupling verification on a defect grating to divide a potential defect region. For a potential defect area, excitation parameters are dynamically adjusted through a gradient descent algorithm, and defect grades are divided by combining the characteristic defect degree and the area. According to the invention, the problems of insufficient single-mode detection, low multi-mode alignment precision and blind adjustment of excitation parameters are solved, cross-band cooperative detection and intelligent grading are realized, and the detection reliability is improved.

The present disclosure provides an optical component, which may be a metasurface grating, including (a) a substrate; and (b) an array of subwavelength-spaced phase-shifting elements, which are tessellated on the substrate to produce, when illuminated with a polarized incident light, a diffracted light beam with a distinct polarization state for each of a finite number of diffraction orders, wherein the finite number is 2 or more.

The invention provides a surface grating surface emitting laser. The surface grating surface emitting laser comprises an N-face metal electrode layer; an N-face waveguide layer, an active layer, a P-face waveguide layer and a ridge waveguide layer are sequentially stacked on the N-face metal electrode layer, wherein the ridge waveguide layer comprises a gain region and a loss region; the P-surface metal electrode layer is arranged on the gain region of the ridge waveguide layer; and the P-surface silicon dioxide layer is arranged on the loss region of the ridge waveguide layer. According to the laser, through the characteristic that mode fields are distributed in a loss area and a gain area after PT symmetric breaking, a light field achieves surface light emitting through vertical diffraction coupling of surface gratings of the loss area, and the laser is different from a common laser structure in which gratings are completely etched in the longitudinal direction and electrodes are manufactured on the two sides. The mode gain difference is symmetrically manufactured through PT, double lobes are eliminated, a single mode is stabilized, lambda / 4 phase shift does not need to be introduced, and the process difficulty is reduced.

The invention relates to a transmission grating and a preparation method thereof, and the transmission grating comprises a substrate which is provided with a first surface; the grating layer comprises trapezoidal grating teeth arranged on the first surface in an array mode, the grating teeth extend in the thickness direction of the substrate, and a gap is formed between every two adjacent grating teeth; the dielectric layer is arranged on the surface of the grating layer and fills the gap, one side, far away from the substrate, of the dielectric layer is provided with a second surface, a difference value exists between the distance between the second surface and the first surface and the height of the grating teeth, and the difference value is m; incident light enters the second surface through the inside of the grating layer. By designing the film layer structure and the film layer size of the transmission grating, the transmission grating with different diffraction efficiencies and polarization degrees can be obtained, the size of the film layer structure of the transmission grating can be accurately controlled during processing, and processing is easy.

The invention discloses a far-field imaging system, a metasurface grating and an imaging terminal, and relates to the technical field of image generation. Dynamic environment compensation and imaging quality optimization are realized through cooperation of multiple modules of the system: the environment temperature is read in real time, the refractive index of the metasurface grating is corrected according to a pre-stored mapping relation, and a target wavefront function is constructed and dispersed to obtain an initial phase distribution matrix; dividing a focusing area in combination with a user sight line, and compensating and regulating a phase distribution matrix by voltage gradient; based on the divided buffer and background regions, a multi-region sampling rate is configured to generate a mask, and the collection efficiency of the key region is improved; monitoring far-field information change in real time, and selecting an interpolation or total variation strategy to update the image; by means of image definition feedback, a secondary phase correction term is superposed to optimize a phase distribution matrix; the problems of traditional far-field imaging in the aspects of environment adaptation, dynamic focusing, data acquisition and imaging quality are solved, and the method is suitable for augmented reality glasses and the like.

The invention relates to the technical field of data retrieval, in particular to a hardware image retrieval method based on deep learning. The method comprises the following steps: acquiring a multi-angle image of hardware to be retrieved, and generating hardware feature data after geometric correction and feature enhancement; and performing shape fuzzy retrieval on a preset hardware image database by using the feature data to generate a shape-like hardware data set. And carrying out surface grating structure construction and optical response simulation on the shape-like data set to generate hardware grating data. Based on the grating data, simulating a light field and collecting four-dimensional reflected light to obtain a four-dimensional data tensor; and associating the tensor with a preset hardware material attribute, and establishing a spectrum-material attribute relationship. Feature matching is carried out according to the relation, and target hardware data are accurately retrieved; according to the hardware image retrieval method, the hardware image retrieval method can be faster and more accurate.

The utility model relates to the technical field of lasers, and discloses a high-slope-efficiency surface grating surface emitting laser which comprises a substrate, a lower waveguide layer, an active layer and an upper waveguide layer from bottom to top along the cross section. A ridge-shaped waveguide is formed in the middle area of the uppermost layer of the upper waveguide layer, and a Bragg grating is etched on the surface of the ridge-shaped waveguide; the Bragg grating comprises a section of second-order grating located in the middle and two sections of first-order gratings located at the two ends; a lambda / 4 phase shift is arranged in the second-order grating; the lambda / 4 phase shift is located in an etching area or a non-etching area of the first-order grating closest to the second-order grating; when the lambda / 4 phase shift is located in the etching region of the first-order grating closest to the second-order grating, the upward diffraction light power of the second-order grating is maximum, and the downward diffraction light power is minimum; when the lambda / 4 phase shift is located in the non-etching area of the first-order grating closest to the second-order grating, the upward diffraction light power of the second-order grating is minimum, and the downward diffraction light power of the second-order grating is maximum. According to the invention, high-slope efficiency lasing can be realized.

The present invention relates to a transmission grating and a preparation method therefor. The transmission grating comprises: a substrate, which has a first surface; a grating layer, which comprises trapezoidal grating teeth arranged in an array on the first surface, wherein the grating teeth extend in the direction of thickness of the substrate, and a gap is provided between two adjacent grating teeth; and a dielectric layer, which is arranged on a surface of the grating layer and fills the gaps, wherein the dielectric layer has a second surface on the side thereof away from the substrate; there is a difference between the height of the grating teeth and the distance between the second surface and the first surface, the difference being m; and incident light passes through the interior of the grating layer and is incident towards the second surface. By means of the design of a film layer structure and film layer dimensions of the transmission grating, the present invention can acquire transmission gratings having different diffraction efficiencies and polarization degrees, and can accurately control the dimensions of the film layer structure of the transmission grating during machining, thereby facilitating machining.

The invention discloses a micro-nano structure optical filter reverse design method based on deep learning. The method comprises the following steps: data preprocessing and data set construction; building a reverse design network model based on deep learning; jointly training the reverse design network to obtain a high-performance model; structural information of the optical filter is derived from the target transmission spectrum, and reverse design of the micro-nano structure optical filter is achieved. According to the micro-nano structure optical filter reverse design method based on deep learning, structure type classification and structure parameter regression are combined, batch processing of multiple micro-nano structures is supported, the limitation that an existing method only aims at a single structure type (such as a metasurface grating or a hole digging structure) is solved, and the method is suitable for large-scale popularization and application. And the universality and the application range of the reverse design are improved.

The invention provides a double-FP waveguide type laser integrated with a surface grating. The double-FP waveguide type laser comprises an N-face metal electrode layer; an N-type substrate, a lower separation limiting layer, an active layer, an upper separation limiting layer and a double-FP-type ridge waveguide layer are sequentially stacked on the N-face metal electrode layer, and the double-FP-type ridge waveguide layer comprises two FP-type ridge waveguides which are arranged in parallel in the first direction; the ohmic contact layer is arranged on each FP type ridge waveguide; and the P-surface metal electrode layer is arranged on the ohmic contact layer. The laser is high in integration, external light feedback and external light injection are not needed, weak periodicity caused by light feedback is avoided, intra-cavity mode distribution is regulated and controlled by changing waveguide distribution and current injection conditions, multiple nonlinear states such as single-period, multi-period and four-wave mixing are achieved, and on-chip chaotic light signal output of a single longitudinal mode is generated.

The invention relates to the technical field of optical design, and discloses a double-beam differential measurement device and method for the polarization sensitivity of a metasurface grating, and the method comprises the steps: dividing a pre-generated light beam into a first light beam and a second light beam through an optical fiber coupler, carrying out the dynamic switching of the polarization state of the second light beam, and obtaining a second incident light beam, adjusting the first light beam based on the second incident light beam to obtain a first incident light beam; enabling the first incident light beam to pass through a first path without the metasurface grating, enabling the second incident light beam to pass through a second path comprising the metasurface grating, and obtaining a first output light beam and a second output light beam; performing time domain difference on the first output light beam and the second output light beam, and calculating to obtain a multi-polarization-state differential signal; correcting the multi-polarization-state differential signal through a preset differential correction mechanism to obtain a corrected differential signal; calculating the polarization sensitivity of the metasurface grating according to the corrected differential signal; according to the invention, the accuracy of the calculated polarization sensitivity of the metasurface grating can be improved.

The invention relates to the technical field of metasurface gratings, and discloses a synchronous testing system and method for diffraction efficiency and field angle of metasurface grating waveguide, and the system comprises a light source module which responds to a preset target field angle range, encodes the phase and frequency of a light beam through a composite encoding method, and obtains an incident light beam; the diffraction module is used for dividing the metasurface grating waveguide into a plurality of sub-regions, respectively inputting an incident light beam into each sub-region for diffraction, and collecting a diffracted light beam diffracted by the metasurface grating waveguide in each sub-region; the parameter coupling module is used for performing coupling calculation on a plurality of parameters in the diffracted beams of each sub-region through a parameter coupling method to generate a coupling matrix; the decoupling analysis module decouples the coupling matrix through a preset parameter decoupling model to obtain the diffraction efficiency and the field angle of the metasurface grating waveguide; according to the invention, high-precision synchronous measurement of the diffraction efficiency and the field angle of the metasurface grating waveguide can be realized.

The invention relates to polymerizable liquid crystal formulations (as a subcategory of liquid crystal material), especially to polymerizable ink formulations for inkjet printing, which are preferably PFAS-free (for enabling the reduction of perfluorocarbons and providing an environment friendly material), and which are comprising one or more polymerizable mesogenic compounds, also known as reactive mesogens (RMs), and one or more organic solvents selected from the group of aromatic ester and aromatic or aliphatic diester solvents, to polymers and polymer films obtained from such formulations, and to the use of the formulations, polymers and polymer films in optical or electrooptical components or devices, especially for digital optics or augmented reality or virtual reality (AR / VR) applications like polarizers, optical compensators, reflective films, diffraction or surface gratings, Bragg polarization gratings (Bragg PG), polarization volume gratings (PVG), polarization volume holograms (PVH), Pancharatnam Berry (PB) gratings, nonmechanical beam steering elements, optical waveguides, optical couplers, optical combiners, polarization beam splitters, partial mirrors, lenses or PB lenses.

This application discloses a method and system for synchronous testing of metasurface grating waveguide performance, relating to the field of metasurface grating technology. The method includes polarization state modulation and spatial frequency encoding of multi-wavelength incident beams to obtain a modulated incident light field; coupling this modulated incident light field into the metasurface grating waveguide under test, which then undergoes total internal reflection to form the outgoing light field; acquiring a raw dataset of the entire light field, including Stokes polarization images and spatial spectrum images corresponding to each wavelength of the outgoing beam; calculating the total internal reflection hop count based on the Stokes polarization image; calculating the spatial step size offset based on the spatial spectrum image; and establishing a mapping relationship between the image pixel coordinates of the raw dataset and the internal physical regions of the metasurface grating waveguide under test to obtain local diffraction efficiency distribution data. This application solves the problem that traditional outgoing end intensity testing is difficult to trace to local defects inside the waveguide, achieving synchronous, high-precision quantitative characterization of local diffraction efficiency across multiple wavelengths.

An existing method has defects in the aspect of continuous fiber reinforcement path planning of a grating structure, so that a path generation method capable of optimizing the fiber content and exerting the fiber continuity is needed, and efficient 3D printing forming is achieved. The invention provides a grating structure suitable for continuous fiber reinforced 3D printing and a printing method of the grating structure. According to the method, printing of a grid structure in two directions is achieved through optimized path planning, and the requirements of curved surface printing and multilateral grid expansion can be met. According to the structural design, structures such as auxiliary frames are allowed to be printed, and variable-thickness grating design can be achieved, so that the mechanical property of the overall structure is improved. The printing strategy is composite printing of resin and continuous fibers, the fibers form a main bearing structure through a one-stroke path, the resin is used for area filling, and the overall strength is improved. The high-performance composite material is suitable for the fields of aerospace, buildings and other fields needing high-performance composite material structures.

The embodiment of the invention relates to a surface emitting laser and a light emitting unit. The surface emitting laser includes: a substrate; the bottom reflector structure, the active layer and the top reflector structure are arranged on the substrate; the at least two surface grating units are formed on the surface of the top reflecting mirror structure and located in a lasing area of the surface emitting laser, and each surface grating unit is configured to enable the polarization selection mode of at least one surface grating unit to be different from the polarization selection modes of the other surface grating units. According to the scheme, emission and polarization control of non-fundamental mode laser can be restrained in a targeted mode, selective single / multi-mode stable output is achieved, and the mode hopping phenomenon is reduced.

Extended cavity diode laser devices and methods of fabrication are provided, wherein the diode laser devices comprise, in the longitudinal direction, an amplifier section, a passive propagation section, and a Bragg section. The amplifier section, the propagation section, and the Bragg section are arranged between a front facet and a rear facet, wherein an active layer is formed in of the amplifier section over the entire length of the amplifier section and, in the Bragg section, a surface grating extends over the entire length of the Bragg section, and the surface grating is formed by a plurality of grooves spaced apart from each other in the longitudinal direction.

The present disclosure relates to highly efficient curved holographic aligned nonlinear grating elements (CHANGE) for high-resolution high-performance augmented and virtual reality. In embodiments, a curved shape can be designed by input angle and output angle for each position of the CHANGE. Each position has a different grating direction (x) and a different period. For AR devices, two-dimensional image sources from the displays can be used. Thus, CHANGES can be applied for both in-coupling and out-coupling diffractive metasurface optical elements (MOEs) instead of using a two-dimensional grating. In the in-coupling MOE region, collimated display input source can be diffracted and guided into waveguide glass and magnified for both of the two-dimensional directions at the out-coupling region by using in-coupling CHANGE. In an out-coupling MOE region, a magnified two-dimensional image is focused at the eyebox by using out-coupling CHANGE. Thus, using CHANGE components according to embodiments, various sizes of input two-dimensional image sources can be converted to target sizes of two-dimensional images at the eyebox with high efficiency.

The invention relates to a half-wave plate comprising two layers of a chiral liquid crystal (LC) polymer with a pitch gradient (as a subcategory of liquid crystal material), a method for its preparation, and its use as diffractive optical element in optical or electrooptical components or devices, especially for digital optics or augmented reality or virtual reality (AR / VR) applications like polarizers, optical compensators, reflective films, diffraction or surface gratings, Bragg polarization gratings (Bragg PG), polarization volume gratings (PVG), polarization volume holograms (PVH), Pancharatnam Berry (PB) gratings, nonmechanical beam steering elements, optical waveguides, optical couplers, optical combiners, polarization beam splitters, partial mirrors or lenses.

The invention provides a vertical cavity surface emitting laser with a metal grating structure, and relates to the field of semiconductor photoelectrons. The vertical cavity surface emitting laser comprises a light emitting device comprising an ohmic contact layer and a first electrode layer; the grating layer is formed on the surface of the ohmic contact layer, the grating layer comprises a plurality of columnar grating protrusions and grating gaps, and the grating gaps are formed around the grating protrusions; wherein the grating protrusions are made of metal materials, and the grating protrusions are connected with the first electrode layer. The metal grating structure can be used as an electrode of the vertical-cavity surface-emitting laser, ohmic contact of a device is achieved, and meanwhile the vertical-cavity surface-emitting laser can have the polarization characteristic. According to the metal grating structure, the current density distribution of the device can be uniform while the electrode and polarization characteristics are considered, so that the device has a better temperature characteristic. Compared with a traditional grating structure, the metal grating structure is simpler in preparation method and lower in cost in device preparation.

The invention relates to the technical field of semiconductor lasers, in particular to a dual-wavelength semiconductor laser based on grating width modulation and a preparation method thereof, and the laser comprises a ridge waveguide and a surface grating arranged on the ridge waveguide; the surface grating has a single fixed period; the laser comprises a first lasing area and a second lasing area along the cavity length direction, and the grating width of the first lasing area is different from that of the second lasing area; at least one isolation groove is formed between the first lasing area and the second lasing area; the first lasing area and the second lasing area are respectively provided with a first electrode and a second electrode. Through optimization of the structure and the process, the dual-wavelength light source integrates dual wavelengths, power stability and manufacturing feasibility, and is suitable for a light source for Raman detection.

The invention provides an optimization processing method and device of a spectrograph and the spectrograph, and relates to the field of optical technology and the like. The method comprises the following steps: determining an optimization object, wherein the optimization object comprises a first metasurface grating in the spectrometer; determining an optimization mode matched with the optimization object according to an optimization demand corresponding to the optimization object; and performing optimization processing on the structure of the optimization object according to the determined optimization mode to obtain a target optimization structure. By applying the scheme of the invention, the performance of the metasurface grating and the like can be improved.

The invention relates to polymerizable liquid crystal compositions (as a subcategory of liquid crystal materials) comprising an alignment additive, which are preferably PFAS-free (for enabling the reduction of perfluorocarbons and providing an environment friendly material), to formulations, polymers and polymer films obtained from such compositions, and to the use of the compositions, formulations, polymers and polymer films in optical or electrooptical components or devices, especially for digital optics or augmented reality or virtual reality (AR / VR) applications like polarizers, optical compensators, reflective films, diffraction or surface gratings, Bragg polarization gratings (Bragg PG), polarization volume gratings (PVG), polarization volume holograms (PVH), Pancharatnam Berry (PB) gratings, nonmechanical beam steering elements, optical waveguides, optical couplers, optical combiners, polarization beam splitters, partial mirrors, lenses or PB lenses.

This invention provides a photosensitive polyurethane film with a surface grating, its preparation method, and its applications. The photosensitive polyurethane film with a surface grating exhibits well-defined and controllable photoresponse characteristics. Its core mechanism lies in the photosensitive monomer responding to light stimulation of a specific wavelength through a dimerization reaction: under ultraviolet light irradiation, the photosensitive monomer in the film undergoes a [2+2] cycloaddition to generate a four-membered cyclobutane dimer. This response mechanism is clear, the triggering path is independent, and the response efficiency is high. It effectively overcomes the limitations of existing coumarin derivatives, which can only achieve self-healing technology. By controlling parameters such as irradiation time and number of irradiations, multi-dimensional information storage can be achieved, significantly improving information storage capacity and stability. This effectively solves the urgent problem of high-capacity information storage in the current field of optical encryption materials, providing a feasible technical path for improving the performance and expanding the practical applications of optical encryption materials.

A diffractive optical element comprising at least one achromatic half-wave plate and at least one chromatic half-wave plate, each half-wave plate comprising at least two layers of a polymerized chiral liquid crystal (LC) material on a substrate, wherein at least one of the substrates has a periodic surface grating, a method for its preparation. Also, its use in optical or electrooptical components or devices, especially for digital optics or augmented reality or virtual reality (AR / VR) applications like non-mechanical beam steering elements, optical waveguides, optical couplers, optical combiners, optical deflectors, polarization beam splitters, partial mirrors or lenses.

The present invention relates to a transmission grating and a method for manufacturing the same. The grating comprises a substrate having a first surface; a grating layer comprising trapezoidal grating teeth arrayed on the first surface, the grating teeth extending along the thickness of the substrate, with gaps between adjacent grating teeth; a dielectric layer disposed on the surface of the grating layer and filling the gaps, the dielectric layer having a second surface on a side facing away from the substrate, the second surface having a distance from the first surface and a height difference between the grating teeth, the difference being m; and incident light passing through the interior of the grating layer and incident toward the second surface. The present invention can design the film structure and dimensions of the transmission grating to obtain transmission gratings with different diffraction efficiencies and polarization degrees. This allows for precise control of the dimensions of the transmission grating film structure during processing, thereby facilitating easy processing.

The invention discloses a GaN-DFB laser based on a porous gallium nitride coating layer and a preparation method, and belongs to the field of semiconductor lasers, and the GaN-DFB laser sequentially comprises a substrate layer, a bottom GaN layer, a GaN-n layer, a porous GaN layer, a lower intrinsic GaN layer, a quantum well active layer, an upper intrinsic GaN layer, an AlGaN-p barrier layer and a GaN-p layer from bottom to top. Porous GaN which is low in refractive index and controllable is used as a coating layer, the grating is formed through surface etching, the grating structure and the layer structure are optimized, the active layer and the surface grating layer can have high resonance light field coupling strength at the same time, low-threshold, efficient and high-performance light lasing can be achieved, and the light emitting efficiency is improved. Therefore, the novel GaN-DFB laser is prepared.

The invention relates to the technical field of intelligent riding glasses, and discloses an information screen projection method and device for intelligent riding glasses, and the method comprises the steps: collecting a riding environment feature data set in a riding process, and generating a riding vibration compensation parameter set and an ambient light adaptation parameter set according to the riding environment feature data set; performing optical waveguide coupling on the intelligent riding glasses to obtain a dynamic diffraction angle adjustment parameter set; according to the dynamic diffraction angle adjustment parameter set, performing adaptive modulation on an electric control liquid crystal layer and a nano surface grating in the optical waveguide to obtain an optical waveguide coupling efficiency optimization result; the backlight power and display image parameters are cooperatively adjusted based on the optical waveguide coupling efficiency optimization result, and an intelligent screen projection display result is output, the problem that display lags when the ambient light rapidly changes is effectively solved, real-time adjustment of the optical characteristics of the optical waveguide is achieved, and consistency and stability of screen projection display quality are ensured.

The invention provides an infrared eye movement tracking device and eye movement tracking equipment, and relates to the technical field of eye movement tracking. The device comprises a single infrared light emitting diode, a collimating element, a metasurface device, an image sensor and a control processing unit. The metasurface device is arranged on the light emitting path of the collimating element and located between the infrared light emitting diode and the human eye observation area; the metasurface device is a device designed based on a two-dimensional metasurface grating structure and is configured to diffract and modulate an incident light beam into a plurality of illumination light beams separated in space so as to form a plurality of light spots distributed in a concentric ring shape on the cornea surface of a target eyeball; the image sensor is used for collecting a cornea reflection image containing a plurality of light spots; and the control processing unit is in communication connection with the image sensor and is used for outputting sight line direction data based on the relative position relationship between a plurality of light spots in the cornea reflection image and the pupil center, so that the eye movement tracking performance with higher precision and higher reliability is realized while hardware is simplified.

The invention provides an extreme ultraviolet collection mirror grating hybrid measurement system and method, and relates to the technical field of extreme ultraviolet (EUV) lithography and nanometer metrology, and the system comprises an atomic force microscopic module which is in communication connection with a data processing module and is used for carrying out high-resolution morphology detection on an abnormal morphology according to position information, and obtaining image data; the shared precision positioning platform module is connected with the optical scattering measurement module and the atomic force microscopy module and used for controlling movement of the optical scattering measurement module and the atomic force microscopy module so that the atomic force microscopy module can accurately move to the position where the abnormal morphology is located; wherein the data processing module is also used for generating a comprehensive detection report based on the geometric structure parameters reconstructed by the optical scattering measurement module and the image data acquired by the atomic force microscopic module. According to the invention, high-precision, high-efficiency, cross-scale and lossless comprehensive characterization of the grating on the surface of the EUV collecting mirror can be realized.