50 results about "Grating pattern" patented technology

This invention discloses a three-dimensional contour measurement method and apparatus based on multi-projection gratings, relating to the field of three-dimensional topography measurement technology. The method includes: obtaining intrinsic and extrinsic parameters through calibration; projecting a set of speckle patterns; preliminarily analyzing the surface topography gradient of the object to determine a non-uniform spatial frequency sequence; sequentially projecting and acquiring multiple sets of phase-shifting grating patterns, and calculating the wrapping phase map corresponding to each frequency; for the same pixel, based on its reliability assessment in wrapping phase maps at different frequencies, assigning confidence weights to the phase values ​​of each frequency, and calculating and optimizing the phase map and the corresponding fused confidence map; calculating gradient information and combining it with the fused confidence map to perform region division, and executing a region-guided path consistency verification unfolding algorithm to obtain the absolute phase; converting the absolute phase into three-dimensional point cloud coordinates of the object surface. This application aims to solve the problems of complex topography, discontinuities, and noise easily leading to unfolding path errors and order jumps during phase unfolding.

The application discloses a laser scanning welding system and method for ultrathin high polymer diaphragms, aiming at solving the technical problem that the ultrathin diaphragm is easy to deform during welding. The system comprises an ultrasonic welding module, a laser welding module and a spatial frequency domain imaging module. During welding, the edges of the upper frame of the diaphragm, the ultrathin high polymer diaphragm and the lower frame of the diaphragm are first positioned by preliminary spot welding through the ultrasonic welding module; then, the laser welding module utilizes the characteristics that the upper frame of the diaphragm is transparent and the lower frame of the diaphragm is light-absorbing, so that the laser penetrates the upper frame and performs scanning welding at the contact interface of the diaphragm and the lower frame, realizing fusion; in this process, the spatial frequency domain imaging module projects a grating pattern on the surface of the diaphragm and analyzes the deformation, calculates the welding thermal field distribution in real time, and then feeds back the control of the laser parameters, so that the deformation amount of the diaphragm is always within the controllable range. The application realizes high-precision, low-heat-affected and non-deformation welding of the ultrathin high polymer diaphragm.

An angular sensitive time-of-flight position sensor device is provided and includes an array of pixels each comprising: a planar waveguide structure; a collection area with a grating pattern at a specific periodicity to couple incident light into the planar waveguide structure; at least one detector placed outside of the collection area and in a plane different from that of the planar waveguide structure; an output coupler to direct the light from planar waveguide to the at least one detector; a mask to shield the at least one detector from direct illumination; a narrow band light source that illuminates a field-of-view; a first electronics configured to detect the time-of-flight of light retroreflected, scattered, or both incident onto the position sensor and configured to provide distance ranging information; and a second electronics configured to interpret and retain time-of-flight information and configured to communicate with external electronics for system applications.

This application provides a driving method for a silicon-based liquid crystal, a silicon-based liquid crystal, and a wavelength selective switch, relating to the field of optical switching engine technology. This driving method for the silicon-based liquid crystal can reduce the risk of instantaneous excessive power while shortening the switching time. The driving method includes: dividing the area of ​​the silicon-based liquid crystal that receives a single-wavelength optical signal into M sub-regions, where M is a positive integer greater than or equal to 2, and each sub-region includes at least one row of pixels; sequentially refreshing the M sub-regions to form a first grating pattern, wherein at least two sub-regions have different overshoot power outputs of optical signals based on the first grating pattern; sequentially refreshing the M sub-regions to form a second grating pattern, the second grating pattern being determined by the output angle of the single-wavelength optical signal and the steady-state power of the single-wavelength optical signal; the difference between the overshoot power and the steady-state power of the single-wavelength optical signal output from the area covered by the light spot is less than a preset value.

The invention discloses a programmable optical frequency comb light source based on a dispersion reconfigurable microcavity, and the structure of the programmable optical frequency comb light source comprises a grating writing and dispersion detection module, an integrated microcavity module with a photoinduced refraction characteristic, an optical comb pumping and spectrum sensing module, and a feedback control and signal processing module. The working principle is as follows: on a micro-ring resonant cavity with a photorefractive effect, laser is written into a programmable Bragg grating, so that a dispersion curve of the micro-cavity is reconstructed in real time; then, an intelligent feedback closed loop is formed by monitoring the spectrum and repetition frequency of the output optical comb and comparing the spectrum and repetition frequency with a target set by a user, and the grating pattern is automatically adjusted until the output spectrum is matched with the target. The programmable optical frequency comb light source can be dynamically reconstructed or switched according to different application requirements. The programmable optical frequency comb can be used as a light source module of a co-packaging optical technology, bandwidth density is improved, power consumption is reduced, and therefore the programmable optical frequency comb can be widely applied to interconnection of next-generation data centers.

This invention discloses an electronic cigarette with a dynamic grating pattern effect, including a main unit and an atomizer electrically connected to the main unit. The main unit has a panel assembly, which includes a light-transmitting sheet exposed outside the main unit, a grating plate corresponding to the back of the light-transmitting sheet, and a pattern plate pasted on the back of the grating plate. The pattern plate has multiple images corresponding to the grating plate. Rotating the main unit causes the images to diffract through refraction by the grating plate, and the movement or switching of the images can be observed outside the main unit through the light-transmitting sheet. The main unit has a light panel corresponding to the pattern plate, and a power supply assembly for powering the light panel and the atomizer. This invention, through the design of the panel assembly and light panel, allows the images to change dynamically when the main unit is rotated, making the electronic cigarette not only fun and playable but also more aesthetically pleasing. Furthermore, the aesthetic appeal is enhanced at night by the light from the light panel.

The invention belongs to the technical field of infrared optical devices, and particularly relates to a long-wave infrared band 8-12 [mu] m narrow-band polarization-independent notch filter and a method. The long-wave infrared band 8-12 [mu] m narrow-band polarization-independent notch filter comprises a polished ZnSe substrate, a Ge zero-contrast grating layer, a ZnSe anti-reflection grating layer and two double-layer grating structures, and the two double-layer grating structures are in orthogonal cascade connection and used for achieving the polarization-independent characteristic. The preparation of the optical filter is completed through the six steps of substrate pretreatment, Ge film deposition through electron beam evaporation, grating pattern formation through laser direct writing gray exposure, Ge grating structure preparation through inductive coupling plasma etching, and ZnSe anti-reflection grating layer and orthogonal cascade double-layer grating structure deposition. The preparation method adopts the processes of laser direct writing, ICP etching, electron beam evaporation coating and the like, solves the problems of time consumption of traditional multilayer film deposition, polarization sensitivity of an existing GMR device and the like, and is suitable for the field of long-wave infrared photon and optoelectronic devices.

The invention discloses a laser scanning welding system and method for an ultra-thin polymer vibrating diaphragm, and aims to solve the technical problem that the ultra-thin vibrating diaphragm is easy to deform during welding. The system comprises an ultrasonic welding module, a laser welding module and a spatial frequency domain imaging module. During welding, firstly, the edges of the vibrating diaphragm upper frame, the ultra-thin polymer vibrating diaphragm and the vibrating diaphragm lower frame are subjected to preliminary spot welding positioning through the ultrasonic welding module; then, the laser welding module enables laser to penetrate through the upper frame according to the characteristics that the upper frame of the vibrating diaphragm is transparent and the lower frame of the vibrating diaphragm absorbs light, scanning welding is conducted on the contact interface of the vibrating diaphragm and the lower frame, and fusion is achieved; in the process, the spatial frequency domain imaging module projects grating patterns to the surface of the vibrating diaphragm and analyzes deformation of the vibrating diaphragm, welding thermal field distribution is calculated in real time, laser parameters are fed back and controlled, and it is ensured that the deformation amount of the vibrating diaphragm is always within a controllable range. According to the invention, high-precision, low-heat-influence and deformation-free welding of the ultrathin high-molecular vibrating diaphragm is realized.

The utility model relates to the technical field of semiconductor thin films, and discloses an optical coating structure of a multi-junction solar cell, which comprises a solar cell chip, an antireflection film connected to the solar cell chip and a fourth material layer connected to the antireflection film, the antireflection film comprises at least one first material layer, at least one second material layer and at least one third material layer which are sequentially stacked on the solar cell chip; wherein the fourth material layer comprises a submicron grating and a grating pattern groove, and the submicron grating is connected to the side, away from the second material layer, of the third material layer; and the grating pattern groove is connected and communicated to the third material layer through one side, deviating from the third material layer, of the submicron grating on the submicron grating. According to the multi-junction solar cell, the photoelectric conversion efficiency of the multi-junction solar cell is improved, and the sunlight reflectivity of the multi-junction solar cell is reduced.

The application provides a point light source inscription apodized fiber grating system and a method thereof. The system comprises: a laser for outputting inscription laser; a scanning reflection device for reflecting the laser output by the laser to an inscription area of an optical fiber and scanning the inscription area with the laser; an apodized inscription device for attenuating the power of the laser according to a predetermined attenuation curve; a laser focusing device for focusing the laser on the inscription area to form a grating pattern in the core of the inscription area; and a reference platform for mounting the laser, the scanning reflection device, the apodized inscription device and the laser focusing device. The system of the application effectively reduces the sidelobes on both sides of the resonance peak and improves the spectral characteristics of the fiber grating.

Device for measuring a radius of curvature. This device comprises: - an array (16) of Bragg gratings, each Bragg grating being fabricated in the core of a multimode optical fiber (14) and having at least three identical motifs aligned one behind the other, - a spectral analyzer (42) configured to: - emit, into the multimode optical fiber, an optical excitation signal the majority of whose power is within a wavelength range [λmin; λmax], then - establish a value for the radius of curvature from the measured amplitude of a power peak in the measured spectral response of a Bragg grating from the array (16), in which, for each Bragg grating from the array (16), the largest transverse dimension of the motifs of that Bragg grating is less than the wavelength λmin. Fig. 3

The utility model provides structured light three-dimensional modeling equipment, which comprises a projection module used for projecting a grating pattern formed based on a DeBruijin coding mode to the surface of an object to be measured, the projection module comprises a transmitting unit and a grating sheet, the grating sheet is provided with a grating stripe sequence formed based on the DeBruijin coding mode, and the transmitting unit is used for transmitting the grating stripe sequence to the surface of the object to be measured. Light emitted by the emitting unit passes through the grating stripe sequence of the grating sheet to form a preset grating pattern; the camera module is used for acquiring a projection image after the projection module projects the grating pattern to the to-be-measured object; and the control module is connected with and controls the projection module and the camera module, and is used for establishing a three-dimensional model of the to-be-measured object according to the projection image acquired by the camera module. According to the technical scheme, the structure is simple, cost is low, precision is high, small-batch production can be achieved, and application in the wide fields of industrial manufacturing, medical cosmetology, cultural relic protection and the like is completely met.

The invention discloses a non-uniform metal polarization grating structure based on equal spacing and a preparation method thereof, and belongs to the field of infrared polarization integrated detection.The preparation method comprises the following steps that firstly, a layer of metal film is evaporated on a super-flat double-polished silicon substrate through the electron beam evaporation technology, then a layer of dielectric film is grown on the super-flat double-polished silicon substrate through PECVD to serve as a hard mask, and then the super-flat double-polished silicon substrate is formed; and then, non-uniform grating patterns with equal intervals and unequal line widths are photoetched by adopting a stepping photolithography technology, the dielectric layer and the metal Al layer are etched by utilizing fluorine-based plasma and chlorine-based plasma respectively, and finally, the preparation of the non-uniform metal polarization grating is completed. According to the invention, by improving the grating structure, on the premise of not additionally arranging special process steps, the consistency and controllability of the exposure energy and the etching rate are realized, the problems of complicated exposure process, non-uniform etching rate and the like of the traditional non-uniform grating are successfully solved, and the quality and the performance of the non-uniform grating are remarkably improved.

Device for measuring a radius of curvature. This device comprises: - an array (16) of Bragg gratings, each Bragg grating being fabricated in the core of a multimode optical fiber (14) and having at least three identical motifs aligned one behind the other, - a spectral analyzer (42) configured to: - emit, into the multimode optical fiber, an optical excitation signal the majority of whose power lies within a wavelength range [λmin; λmax], then - establish a value for the radius of curvature from the measured amplitude of a power peak in the measured spectral response of a Bragg grating from the array (16), in which, for each Bragg grating from the array (16), the largest transverse dimension of the motifs of that Bragg grating is less than the wavelength λmin. Fig. 3

According to an embodiment of the present invention, the light guide device comprises an input diffraction element, a transfer diffraction element, and a substrate on which the input diffraction element and the transfer diffraction element are disposed. The transfer diffraction element includes two separately formed regions (a first region and a second region). The first region includes a first grating pattern. The height of the first grating pattern gradually decreases in a direction away from the input diffraction element. The second region includes a second grating pattern. The height of the second grating pattern may also decrease and then increase in a direction away from the input diffraction element.

A light guide device according to an embodiment of the present invention comprises: an input diffraction element; a transmission diffraction element; and a substrate on which the input diffraction element and the transmission diffraction element are disposed, wherein the transmission diffraction element includes a first region and a second region formed by dividing the transmission diffraction element in two, the first region includes a first grating pattern, the height of the first grating pattern changes with distance from the input diffraction element, the second region includes a second grating pattern, the height of the second grating pattern also changes with distance from the input diffraction element, and the height of the first grating pattern and the height of the second grating pattern may be different from each other.

The application discloses a lens defect detection system and method using structured light, a structured light generation method and an image processing method thereof. The structured light projection scheme is adopted, the projected grating pattern is realized by programming, the fineness of the grating stripe can be adjusted according to the actual lens condition, and the defects of the lens surface in different conditions can be more clearly reflected. The designed structured light projection lens can effectively correct various aberrations and has good imaging quality. The projection lens is a zoom system, the focal length range of the system is 11mm-22mm, has a two-fold zoom effect, and can adapt to most lens sizes. The structured light projection system and the collection system adopt a symmetrical structure, can effectively eliminate system distortion and reduce errors. The image processing algorithm of the application can accurately obtain the lens surface defect information.

A light guide apparatus, according to an embodiment of the present invention, comprises: a plate portion in which light is totally reflected internally; a first diffraction portion diffracting the light, which is totally reflected inside the plate portion, to the outside; a second diffraction portion diffracting the light, which is incident into the plate portion, toward the first diffraction portion; and a camera module disposed adjacent to the first diffraction portion and into which the light diffracted by the first diffraction portion is incident, wherein the first diffraction portion and the second diffraction portion include a grating pattern having an inclination on an incident surface onto which the light is incident, and the plate portion is inclined toward an object.

This device comprises: - an array (16) of Bragg gratings, each Bragg grating being made in the core of a multimode optical fiber (14) and comprising at least three identical patterns aligned one behind the other, - a spectral analyzer (42) configured to: - emit, in the multimode optical fiber, an optical excitation signal the majority of whose power is within a wavelength range [λmin; λmax], then - establish a value of the radius of curvature from the measured amplitude of a power peak of the measured spectral response of a Bragg grating of the array (16), in which, for each Bragg grating of the array (16), the largest transverse dimension of the patterns of that Bragg grating is less than the wavelength λmin.

The invention provides a multi-modal data collaborative data labeling method, system and device, and belongs to the technical field of data labeling, and the method comprises the steps: obtaining a color picture and surface attribute text data of a target commodity, and obtaining a deformed grating image sequence through projecting a coding grating pattern to the surface of the commodity and capturing deformed images from different angles; performing semantic analysis on the text data to extract a surface feature vocabulary set; the three-dimensional coordinates of the surface points are calculated by decoding the deformed grating image sequence, and a three-dimensional point cloud model is constructed; calculating local geometric feature parameters of the point cloud, and generating geometric feature descriptors to quantify the surface microstructure; performing spatial registration on the three-dimensional point cloud and the color picture to establish a mapping relation; on the basis of the mapping relation, the geometric feature descriptors and the surface feature vocabularies are associated and matched, the material and the process of the target area in the color picture are recognized, labeling information with attribute labels is generated, and accuracy and comprehensiveness of data labeling of the commodity picture can be achieved.

A light guide device according to an embodiment of the present invention comprises: an input diffraction element including a first region having a first grating pattern and a second region having a second grating pattern; a transmission diffraction element including a third region having a third grating pattern and a fourth region having a fourth grating pattern; and an output diffraction element including a fifth region having a fifth grating pattern and a sixth region having a sixth grating pattern, wherein the period of the first grating pattern and the period of the second grating pattern are different from each other, the period of the third grating pattern and the period of the fourth grating pattern are also different from each other, and the period of each grating pattern may be set such that all the wavelengths of light incident on the input diffraction element are propagated.

The invention provides a method for improving grating uniformity of an SGDBR laser based on process optimization. The method comprises the following steps: performing epitaxial growth of an epitaxial layer on a substrate for the first time to obtain a grating layer; grating pattern photoetching is carried out on the grating layer, and etching of a grating structure is completed through dry etching; performing secondary epitaxy on the substrate subjected to grating etching, and growing a quantum well structure on the whole substrate until a preset waveguide etching stop layer is reached; defining a passive waveguide butt joint area through photoetching, and completely etching and removing the grown quantum well structure in the passive waveguide butt joint area by adopting dry etching and wet etching processes to expose the grating layer; performing butt-joint epitaxial growth on the etched passive waveguide butt-joint area to form a passive waveguide structure; and carrying out three times of epitaxial growth on a material required by the ridge waveguide on the passive waveguide structure, and forming the ridge waveguide structure through photoetching and dry etching processes. According to the invention, the uniformity of the grating is obviously improved, the process stability is enhanced, the device performance is optimized, and the compatibility is good.

This invention discloses a method for fabricating a high aspect ratio X-ray grating and the X-ray grating itself, relating to the fields of micro / nano fabrication and X-ray optical device manufacturing technology. The method includes: using a highly doped, low-resistivity single-crystal silicon wafer as a substrate, cleaning it, and then depositing a silicon dioxide hard mask on its surface; transferring the grating pattern to the silicon dioxide hard mask, and etching it using an improved low-temperature Bosch process to create vertical deep trenches; removing the natural oxide layer on the back side, followed by depositing a metal layer and thermal annealing to construct a conductive back electrode; performing multi-stage cleaning; placing the substrate in a bismuth ion-assisted gold sulfite plating solution for electroplating, ensuring that the gold layer fills the vertical deep trenches from the bottom upwards without voids; removing the silicon dioxide hard mask, cleaning, and drying to obtain the X-ray grating. This invention alleviates the technical problems of uneven performance, poor reliability, high production costs, and low production efficiency and yield of X-ray gratings fabricated by existing technologies.

The invention provides a super-resolution dual pattern processing method. The super-resolution dual pattern processing method comprises the steps of forming a stop layer, a sacrificial layer, a photosensitive film layer and an imaging enhancement layer which are stacked on a substrate; aligning the mask with the substrate, exposing the photosensitive film layer, and developing to form a grating pattern; depositing anti-etching layers on the two sides of the grating pattern line, and etching the anti-etching layer and the photosensitive film layer in the line gap to form a line width modified grating pattern; transmitting the grating pattern to a stop layer; removing the remaining photosensitive film layer and sacrificial layer, and forming a sacrificial layer, a photosensitive film layer and an imaging enhancement layer which are stacked on the stop layer; aligning the mask and the substrate, moving for 1 / 2 grating period towards the direction vertical to the grating direction, exposing the photosensitive film layer, and developing to form a grating pattern; depositing anti-etching layers on the two sides of the grating pattern lines, and etching the anti-etching layers and the photosensitive film layers in the gaps of the grating pattern lines to form grating patterns after line width modification; and transmitting the grating pattern to the stop layer to form a super-resolution double pattern.

This invention relates to the field of optical window technology, and more particularly to a metal mesh grating exposure system and method for sapphire optical windows. The method includes the following steps: acquiring substrate feature data, photoresist feature data, exposure light source feature data, and metal mesh grating pattern structure feature data of the sapphire optical window; predicting standing wave effects and determining exposure dose fluctuation characteristic parameters under the influence of standing wave effects; analyzing the coupling degree between the metal mesh grating pattern structure and the standing wave effect, and determining the standing wave coupling characteristic parameters under the influence of the metal mesh grating pattern structure; determining the exposure dose fluctuation range in different regions of the sapphire optical window; and providing early warning of metal mesh grating exposure quality based on the matching relationship between the exposure dose fluctuation range and the photoresist exposure dose process window. This invention improves the process stability and reliability of metal mesh grating exposure by quantifying the standing wave amplification effect and periodic resonance effect caused by the metal mesh grating pattern structure.

Quench detection apparatuses and methods for high-temperature-superconducting (HTS) cables are described. An optical fiber may form part of the HTS cable and may include a plurality of fiber Bragg gratings (FBGs), at least some of which exhibit different center wavelengths. The FBGs are arranged in some embodiments such that the center wavelengths of the respective FBGs increase along the length of the HTS cable.

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Systems include an x-ray optical arrangement that includes an x-ray source configured to emit an x-ray beam along a beam path and through an object placement location situated to receive an object for inspection, an object grating situated along the beam path, and a detector situated along the beam path to receive the x-ray beam after propagating through the object grating and object placement location and to detect image data, wherein the object grating includes object grating elements arranged in an object grating pattern; and a movement stage providing a plurality of computed tomography imaging positions for the object by the x-ray optical arrangement; wherein the object grating pattern and a positioning of the x-ray source, object grating, and detector in relation to each other are configured to provide a plurality of computed tomography detection modes in the image data.

The utility model relates to the technical field of pattern cloth, in particular to a cloth structure with a grating effect. The cloth structure comprises base cloth, a prime pulp layer, a reflective mirror surface coating or a bright surface coating and a grating pattern layer which are sequentially arranged from bottom to top, the grating pattern layer comprises at least two grating patterns, each grating pattern is divided into parallel slits which are equal in width and interval, and the parallel slits of different grating patterns are spliced in an interpenetrating manner; the grating pattern layer is provided with prismatic protrusions, and the parallel slits of the same grating pattern are located on the faces, facing the same direction, of the prismatic protrusions. The bottom paste layer, the reflective mirror surface coating and the bright surface coating are arranged on the base cloth, so that a flat base layer is provided for printing of the grating pattern layer, and the base cloth faces diffuse reflection and dispersion of daily light and sight lines; and then the grating pattern layer is arranged, so that grating patterns can be presented on different planes in a three-dimensional manner, and the grating cloth can present two or more different patterns at different visual angles.

A method for semiconductor metrology includes depositing first and second overlying film layers on a semiconductor substrate and patterning the layers to define overlay targets. The targets include a first grating pattern in the first layer including at least a first linear grating oriented in a first direction and at least a second linear grating oriented in a second direction perpendicular to the first direction, and a second grating pattern in the second layer including at least a third linear grating identical to the first linear grating and a fourth linear grating identical to the second linear grating. The second grating pattern has a nominal offset relative to the first grating pattern of first and second displacements in the first and second directions, respectively. Scatterometry images of the substrate are captured and processed to estimate overlay error between patterning of the first and second layers.