CN115951448A - On-chip integrated AR display element system and method based on reverse design wavelength demultiplexing - Google Patents
On-chip integrated AR display element system and method based on reverse design wavelength demultiplexing Download PDFInfo
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Abstract
The invention discloses an on-chip integrated AR (augmented reality) display element system based on reverse design wavelength demultiplexing, which comprises a medium substrate layer, an optical waveguide layer, an element grating structure and a nano brick structure; the optical waveguide layer is arranged on the medium substrate layer; the element grating structure is arranged on the optical waveguide layer, and the element grating structure adopts a reverse design to carry out structural optimization, so that two light beams with different wavelengths vertically incident to the element grating structure enter the optical waveguide layer along opposite directions; the nano-brick structures are arranged on the optical waveguide layer, and are on the two sides of the element grating structure, the nano-brick arrays are arranged according to the circuitous phase principle, so that guided waves transmitted along the opposite direction on the optical waveguide layer are decoupled into a free space to form an arbitrary optical field when passing through the nano-brick structures, and holographic display of target images is respectively realized.
Description
Technical Field
The invention relates to the technical fields of micro-nano optics, integrated photonics technology, optical waveguide technology and augmented reality display, in particular to an on-chip integrated AR display element system based on reverse design wavelength demultiplexing.
Background
Augmented Reality (AR), one of the most important display technologies, enhances human interaction with the real world through virtual information, and has great potential for development in the fields of transportation, education, health care, and entertainment. Optical waveguide technology is the most promising approach to realize AR display devices, providing an on-chip platform for integrating optical elements to build multifunctional, high-performance and compact optical systems. However, at present, the coupling/decoupling optical element between free-space light and guided wave is generally bulky (such as prism and grating in traditional coupler/decoupler), severely limits the freedom of any optical operation, and has very limited function.
Recently, the super-surface integrated onto optical waveguides, as a new generation of micro-optical devices, can manipulate guided waves and facilitate arbitrary conversion between free-space light and on-chip guided waves. The on-chip metasurfaces inherit the coding freedom of traditional metasurfaces and can design light amplitude, phase and polarization states at sub-wavelength scales to create a variety of practical functions including beam steering, optical routers, lenses and holographic displays. However, implementing fully integrated on-chip meta-systems and creating arbitrary engineered optical functions remains unexplored and challenging. For example, most previous work has focused on only a single coupler/decoupler assembly, lacking complete optical integration for arbitrary transcoding between on-chip and free-space light, and cooperative mating between each element. At present, the function of the coupling/decoupling element is still too simple to perform the customization operation on the incident light.
Disclosure of Invention
The invention mainly aims to provide a complete optical integration which can be used for arbitrary coding conversion between on-chip and free space light and realizes multi-channel integrated AR display.
The technical scheme adopted by the invention is as follows:
the on-chip integrated AR display element system based on reverse design wavelength demultiplexing is provided, and comprises a medium substrate layer, an optical waveguide layer, an element grating structure and a nano brick structure;
the optical waveguide layer is arranged on the medium substrate layer;
the element grating structure is arranged on the optical waveguide layer, and the structure of the element grating structure is optimized by adopting a reverse design, so that two light beams with different wavelengths vertically incident to the element grating structure enter the optical waveguide layer along opposite directions;
the nano-brick structures are arranged on the optical waveguide layer, and are on the two sides of the element grating structure, the nano-brick arrays are arranged according to the circuitous phase principle, so that guided waves transmitted along the opposite direction on the optical waveguide layer are decoupled into a free space to form an arbitrary optical field when passing through the nano-brick structures, and holographic display of target images is respectively realized.
In connection with the above technical solution, the optimization goal of the reverse design is the efficiency and the splitting ratio of the free space light of two different wavelengths coupling into the opposite direction of the optical waveguide layer.
According to the technical scheme, binary coding is specifically adopted in reverse design, the meta-grating structure of the region to be designed is decomposed into a binary sequence with the length of 200, and 1 and 0 respectively represent whether the corresponding region is filled with silicon or is blank; performing electromagnetic simulation on the element grating by using a finite difference time domain method, and calculating a fitness function of the coupling efficiency and the separation ratio; selecting individuals according to the fitness function, and carrying out combination crossing and mutation by means of genetic operators to generate a new population; and circulating the process, outputting the optimal individual and the optimal solution after the termination condition is met, and obtaining the final meta-grating structure.
According to the technical scheme, the arrangement of the nano-brick structures specifically calculates a phase distribution matrix required by realizing target image holography according to a Gerchberg-Saxton algorithm, and then obtains the position information of the nano-bricks according to the relation between the phase given by the roundabout phase and the relative displacement of the nano-bricks, so as to obtain the position arrangement of the nano-bricks in each unit structure.
According to the technical scheme, the dielectric substrate layer is a silicon dioxide layer; the optical waveguide layer is Si deposited on the dielectric substrate layer by adopting a plasma enhanced chemical vapor deposition technology 3 N 4 。
According to the technical scheme, the element grating structure is a one-dimensional grating structure, two opposite optical channels are formed, two light beams with different wavelengths vertically incident to the element grating structure enter the optical waveguide layer along opposite directions;
or the meta-grating structure is a two-dimensional grating, and two opposite optical channels are formed in each dimension.
According to the technical scheme, the nano bricks in the nano brick structure are equal in length and width, are all in sub-wavelength scale, and are completely consistent in size.
And establishing an xoy coordinate system by taking the directions of the two edges parallel to the working surface of the optical waveguide layer as an x axis and a y axis, wherein the long axis and the short axis of the element grating and the nano brick are parallel to the working surface of the optical waveguide layer.
The invention also provides an AR holographic display method based on reverse design wavelength demultiplexing double-color channels, which is characterized in that based on the technical scheme, the AR holographic display element system is integrated on the chip based on reverse design wavelength demultiplexing, the element grating structure is used as a wavelength multiplexing input coupler, the nano brick structure is used as a decoupler, and holographic display of two channels is realized.
The invention also provides application of the on-chip integrated AR display element system based on reverse design wavelength demultiplexing, which is characterized in that the on-chip integrated AR display element system based on reverse design wavelength demultiplexing is integrated into an AR display device as a lens to realize AR display of multiple wavelength channels and project virtual holographic image information into a real environment.
The invention has the following beneficial effects: the invention integrates the wavelength demultiplexing element grating above the waveguide as an incident coupler, and uses the upper surface of the chip as an output decoupler, thereby realizing the customized coupling conversion between free space light and guided wave, and using wavelength selective coding light information to operate, thereby realizing the multi-channel holographic display.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the description of the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.
FIG. 1 is a schematic diagram of the structure and function of a reverse-designed wavelength demultiplexer grating provided in an embodiment of the present invention, in which a 1-element grating structure, a 2-optical waveguide layer, and a 3-medium substrate layer are provided;
fig. 2 is a final structure diagram of a reverse design algorithm flow and optimization of a wavelength demultiplexer grating according to an embodiment of the present invention, where the grating height h is 1 =380nm, waveguide thickness h 2 =220nm, design area length D =20 μm;
fig. 3 is a diagram of the broadband coupling efficiency of the wavelength demultiplexer grating obtained by simulation in the embodiment of the present invention. The efficiency of coupling into the left waveguide at the design wavelength of 550nm is 12.4%, and the efficiency of coupling into the right waveguide at 650nm is 7.1%; the separation ratios at the two operating wavelengths are about 40 and 100, respectively;
FIG. 4 is an electric field distribution diagram of free-space optical graticules with wavelengths of 550nm and 650nm, respectively, obtained by simulation in an embodiment of the present invention;
FIG. 5 is a schematic diagram of a unit structure of the upper surface of the chip provided in the embodiment of the present invention, wherein L = W =90nm, H = h, and L = W =90nm, and L = H = h, and the unit structure includes a 4-nanoblock structure, a 2-optical waveguide layer, and a 3-dielectric substrate layer 1 ＝380nm；
Fig. 6 is a schematic diagram of guided wave manipulation based on a detour phase arrangement super surface in the embodiment of the present invention, wherein the unit structure period Λ =340nm;
FIG. 7 is a schematic flow chart and a simulated hologram for implementing holography based on a detour phase on an on-chip meta-surface in an embodiment of the invention;
fig. 8 is a display diagram of an on-chip super-surface hologram and an AR hologram projection realized based on the proposed full on-chip integrated optical element system in an embodiment of the present invention, in which green "apple" and red "cherry" hologram images are respectively obtained corresponding to 540nm and 610nm wavelength vertical incidence element gratings;
in the figure, the thickness of the silicon nitride waveguide is 220nm, and the thickness of the silicon dioxide substrate is 500 μm; lambda [ alpha ] G And λ R The two working wavelengths are provided, H is the height of the nano brick, Λ is the period of the unit structure in the x direction, and s is the distance of the nano brick moving in the unit structure along the x direction;
fig. 9 is a schematic structural diagram of an on-chip integrated AR display element system based on inverse design wavelength demultiplexing according to an embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not limit the invention.
The invention integrates a wavelength demultiplexing meta-grating incident coupler and an on-chip super-surface output decoupler above a waveguide, realizes customized coupling conversion between free space light and guided wave, and utilizes wavelength selective coding light information to operate.
The on-chip integrated AR display element system based on reverse design wavelength demultiplexing of the embodiment of the invention, as shown in FIG. 9, comprises a medium substrate layer, an optical waveguide layer, an element grating structure and a nano brick structure;
the optical waveguide layer is arranged on the medium substrate layer;
the element grating structure is arranged on the optical waveguide layer, and the structure of the element grating structure is optimized by adopting a reverse design, so that two light beams with different wavelengths vertically incident to the element grating structure enter the optical waveguide layer along opposite directions;
the nano-brick structures are arranged on the optical waveguide layer, and are on the two sides of the meta-grating structure, and are on-chip super-surface nano-brick arrays arranged according to a roundabout phase principle, so that guided waves transmitted along the opposite direction on the optical waveguide layer are decoupled into a free space to form an arbitrary optical field when passing through the nano-brick structures, and holographic display of target images is respectively realized.
The optimization goal of the reverse design is the efficiency and splitting ratio of two different wavelengths of free-space light coupled into the opposite direction of the optical waveguide layer.
In one embodiment of the present invention, the reverse design flow of the wavelength demultiplexing element grating is as follows:
the wavelength demultiplexing element grating adopts a reverse design method, and specifically, a genetic algorithm can be adopted to carry out structural optimization to realize the function which is in line with the expectation. The structural parameters thickness of the meta-grating, waveguide thickness and design region length are initially defined. Incident light is defined as a normally incident gaussian beam containing two specific wavelengths, with polarization perpendicular to the grating. The optimization goal of the reverse design is the efficiency and separation ratio of the two different wavelengths of free-space light coupled into opposite directions of the waveguide. The implementation steps for optimizing the meta-raster by using the genetic algorithm are as follows: decomposing the design region into a binary sequence with the length of 200 by adopting binary coding, wherein 1 and 0 respectively represent whether the corresponding region is filled with silicon or is blank; performing electromagnetic simulation on the element grating by using a finite difference time domain method, and calculating two fitness functions of coupling efficiency and separation ratio; selecting individuals according to the fitness function, and carrying out combination crossing and mutation by means of genetic operators to generate a new population; and circulating the process, and outputting the optimal individual and the optimal solution after the termination condition is met to obtain the final meta-grating structure.
The circuitous phase regulation and control principle of the nano bricks on the super surface of the chip is as follows:
guided waves propagating in the waveguide are extracted by the silicon nano brick structure when passing through the silicon nano brick structure and are decoupled into free space to form an arbitrary optical field, and the phase distribution of the guided waves can be designed by phase accumulation of guided wave propagation. For a guided wave with a propagation constant β propagating along the x-direction, the extracted phase is determined by the initial phase and the propagation distance of the incident light. The period of the nanostructure is set to Λ =2 pi/β = λ 0 /n eff Wherein λ is 0 Is a free space optical wavelength, n eff Is the effective index of the waveguide. When the nano brick structures are distributed in the period lambada, the phase modulation of 0-2 pi can be realized. Through the derivation, the nano brick lifterThe detour phase of the light extraction can be expressed as:
wherein s is n And delta phi n The displacement of the n-th nano-brick in the x direction along the x direction in one period and the corresponding extraction phase. Thus, by strategically distributing the meta-atoms along the waveguide, precise control of the detour phase profile can extract and shape the guided wave into any wavefront in free space to achieve various optical functions.
The arrangement of the nano-brick structures specifically calculates a phase distribution matrix required for realizing target image holography according to a Gerchberg-Saxton algorithm, and then obtains the position information of the nano-bricks according to the relation between the phase given by the roundabout phase and the relative displacement of the nano-bricks, so as to obtain the position arrangement of the nano-bricks in each unit structure. The specific method can also refer to the patents (such as patent numbers cn202111429402.X and CN 202210337142.1) previously applied by the applicant, and the specific description is about how to obtain the phase distribution matrix and the position arrangement of the nano-bricks.
The embodiment of the invention discloses a method for realizing AR holographic display of wavelength demultiplexing double-color channels by using a full on-chip integrated optical element system, which is based on the on-chip integrated AR display element system based on reverse design wavelength demultiplexing of the embodiment, and realizes holographic display of two channels by using an element grating structure as a wavelength multiplexing input coupler and a nano brick structure as a decoupler. The AR holographic display method comprises the following steps:
(1) The selected wavelength demultiplex grating has its working wavelength lambda G 、λ R Optimizing the meta-grating structure by reverse design algorithm to make the wavelength be lambda respectively G 、λ R The free space light of (a) is coupled into the waveguide to form a waveguide with opposite propagation direction;
(2) Selecting two binary images as holographic images of green light and red light wavelength channels, and respectively coding the super surfaces of the corresponding spatial positions according to the propagation directions of the guided waves with different wavelengths;
(3) Acquiring phase matrix distribution of a target far-field holographic image by adopting a GS algorithm, thereby obtaining position information of the silicon nano bricks corresponding to the two super surfaces in the unit structure along the x direction according to a roundabout phase principle and an equation (1), wherein the nano bricks are positioned at the central position of the unit structure in the y direction;
(4) Using a wave containing wavelength lambda G 、λ R The free space polarized light is vertically incident to the element grating to form corresponding wavelength guided waves propagating in opposite directions in the waveguide. The guided waves pass through the super-surface array above the waveguide respectively to obtain an on-chip dual-wavelength channel hologram;
(5) Virtual image information floating in a real environment can be directly shot by using a mobile phone camera, namely the AR holographic display is realized.
The nano structure in the unit structure responding to the green and red wave guide is composed of silicon nano bricks, and the length and width of the nano bricks are equal and are all in sub-wavelength scale and are completely consistent in size.
As a preferred embodiment, the wavelength demultiplexing element grating and the on-chip super surface which are reversely designed are selected and integrated on the waveguide. The meta-grating structure of this embodiment is a one-dimensional grating structure that forms two opposite optical channels, and two light beams of different wavelengths that are perpendicularly incident on the meta-grating structure enter the optical waveguide layer in opposite directions. FIG. 1 is a schematic diagram of a wavelength demultiplexing element grating structure, the grating is located at Si 3 N 4 (thickness 220 nm) waveguide (waveguide can also be made of other materials, such as lithium niobate waveguide, with refractive index higher than that of silicon dioxide), waveguide refractive index is about 2.05, and silicon dioxide layer with thickness of about 500 μm is used as substrate. Fig. 2 is a flow chart of implementing the meta-grating wavelength demultiplexing function by the inverse design algorithm. The structure of the meta-grating is encoded by a binary sequence of length 200, indicating whether the corresponding region is filled with silicon (1) or empty (0). The objective of the inverse design algorithm is to optimize the efficiency and separation ratio of the coupling of two wavelengths into opposite directions of the waveguide. And calculating a fitness function by using electromagnetic simulation software FDTD Solutions, and performing iterative optimization through a genetic algorithm to obtain a final structure meeting the conditions. The structure height of the adopted element grating is h 1 =380nm, waveguide thicknessh 2 =220nm, and the design region length D =20 μm.
Fig. 3 is a diagram of broadband coupling efficiency obtained by simulation in the visible light band using the optimized wavelength demultiplexing element grating structure. The performance of the element grating is expected, the efficiency of coupling into the left waveguide at the design wavelength of 550nm is 12.4%, and the efficiency of coupling into the right waveguide at 650nm is 7.1%; the separation ratio at the two operating wavelengths is about 40 and 100, respectively. In addition, the cross-sectional electric field distribution of the above meta-grating structure with two operating wavelengths incident perpendicularly also illustrates the wavelength demultiplexing function, with 550nm of incident light in free space being coupled into the left side of the waveguide and 650nm of light being coupled into the right side of the waveguide (as shown in the electric field distribution of fig. 4).
In order to realize the extraction of the waveguide formed by coupling into the waveguide and the reconstruction of the holographic image in the free space, the chip super-surfaces are arranged on the two sides of the wavelength demultiplexing grating. The positions of the nano brick arrays can be distributed by adopting circuitous phases to realize phase modulation within a 2 pi range, so that the extracted guided waves are molded into any wave front, and the holography of the on-chip dual-wavelength channel is realized by matching with the wavelength demultiplexing element grating. FIG. 5 is a schematic diagram of a cell structure in which the cell structures of the amorphous silicon nanoballs constituting the upper surface of the sheet are located on the same waveguide and substrate as the meta-grating structure. The height of the silicon nano brick is the same as that of the element grating, and H = H 1 =380nm, the structure length and width dimensions of the nanoblock are L = W =90nm. The super surface adopts a circuitous phase for encoding so as to meet the working requirement of a wide band. Fig. 6 shows the principle of guided wave manipulation of the on-chip super-surface based on a detour phase, and the phase of super-surface extraction is determined by the relative displacement s of nano-bricks in a unit structure within one period (Λ =340 nm). By strategically arranging the silicon nano-brick arrays on the super-surface of the wafer, guided waves can be extracted to any wavefront in free space.
Fig. 7 shows a flow of realizing on-chip holography based on a super-surface of a detour phase, which includes firstly calculating a phase matrix required by a target image by using a GS algorithm, then converting position information by combining the detour phase to obtain position arrangement of corresponding nano-bricks in each pixel, and finally obtaining a holographic image through simulation.
Next, a prototype wafer of on-chip meta-system integrating wavelength demultiplexing grating and on-chip super surface is fabricated. 220nm thick Si was deposited on a 500 μm silicon dioxide layer using Plasma Enhanced Chemical Vapor Deposition (PECVD) technique 3 N 4 A waveguide, and a 380nm thick Si layer is deposited on the waveguide; spin-coating polymethyl methacrylate (PMMA) on the Si layer and baking, using Electron Beam Lithography (EBL), and then developing in solution; and then, transferring the pattern to the Si layer by using the chromium layer as a mask, and finally removing the chromium to obtain a sample wafer.
Laser emitted by a laser source vertically enters the element grating after passing through the linear polarizer, the wavelength demultiplexing function of the element grating is represented by adjusting the wavelength of the light source, and a holographic image is obtained by shooting at the position of the corresponding super surface.
Fig. 8 shows an experimental holographic image with good agreement with the target holographic image. Under illumination with 540nm and 610nm light, images of green "apples" and red "cherries" were captured at output 1 and output 2, respectively. Under the irradiation of a single wavelength, the holographic images of the two output ports have strong contrast.
Finally, in order to verify the practical AR holographic multiplexing function, the virtual information floating in the real world environment is captured by the camera in the mobile phone, as shown in fig. 8. We clearly observe the actual field of view of the green "apples" and red "cherries" floating on the real background image (goggles), with better imaging intensity and clarity. The proposed AR strategy based on a full on-chip integrated optical meta-system is compatible with current PIC technology, which will also show great application potential in wearable device (spectacle lens or contact lens) integration and next generation new screen display technologies.
The meta-grating structure may also be a two-dimensional grating, each forming two opposite optical channels in each dimension. Taking the grating in an orthogonal structure as an example, two opposite optical channels are formed in each direction, and four optical channels are formed in two orthogonal directions.
Due to the good transparent characteristic of the full-dielectric structure and the on-chip optical transmission mechanism, the full-on-chip integrated optical element system can be used as a lens to be integrated into an AR display device on the basis of the AR display full-on-chip integrated optical element system based on reverse design wavelength demultiplexing, the AR display of multiple wavelength channels is realized, and the virtual holographic image information is projected into a real environment. I.e. the projection of virtual images into a real environment, this technology will show great application potential in wearable device (spectacle lens or contact lens) integration and next generation screen display technology.
It will be understood that modifications and variations can be made by persons skilled in the art in light of the above teachings and all such modifications and variations are intended to be included within the scope of the invention as defined in the appended claims.
Claims (10)
1. An on-chip integrated AR display element system based on reverse design wavelength demultiplexing is characterized by comprising a medium substrate layer, an optical waveguide layer, an element grating structure and a nano brick structure;
the optical waveguide layer is arranged on the medium substrate layer;
the element grating structure is arranged on the optical waveguide layer, and the structure of the element grating structure is optimized by adopting a reverse design, so that two light beams with different wavelengths vertically incident to the element grating structure enter the optical waveguide layer along opposite directions;
the nano-brick structures are arranged on the optical waveguide layer, and are on the two sides of the element grating structure, the nano-brick arrays are arranged according to the circuitous phase principle, so that guided waves transmitted along the opposite direction on the optical waveguide layer are decoupled into a free space to form an arbitrary optical field when passing through the nano-brick structures, and holographic display of target images is respectively realized.
2. The integrated AR display meta-system on-chip based on inverse design wavelength demultiplexing according to claim 1, wherein the optimization goals of the inverse design are the efficiency and the splitting ratio of the two different wavelengths of free space light coupling into opposite directions of the optical waveguide layer.
3. The on-chip integrated AR display meta-system based on inverse design wavelength demultiplexing according to claim 1, wherein the inverse design specifically employs binary coding, the meta-grating structure of the region to be designed is decomposed into a binary sequence with a length of 200, 1 and 0 respectively represent whether the corresponding region is filled with silicon or is empty; performing electromagnetic simulation on the element grating by using a finite difference time domain method, and calculating a fitness function of the coupling efficiency and the separation ratio; selecting individuals according to the fitness function, and carrying out combination crossing and mutation by means of genetic operators to generate a new population; and circulating the process, outputting the optimal individual and the optimal solution after the termination condition is met, and obtaining the final meta-grating structure.
4. The on-chip integrated AR display meta-system based on inverse design wavelength demultiplexing according to claim 1, wherein the arrangement of the nano-brick structures calculates a phase distribution matrix required for realizing target image holography specifically according to a Gerchberg-Saxton algorithm, and then obtains the position information of the nano-bricks according to the relationship between the phase given by the roundabout phase and the relative displacement of the nano-bricks, so as to obtain the position arrangement of the nano-bricks in each unit structure.
5. The integrated AR display meta-system on-chip based on inverse design wavelength demultiplexing according to claim 1, wherein the dielectric substrate layer is a silicon dioxide layer; the optical waveguide layer is Si deposited on the dielectric substrate layer by adopting a plasma enhanced chemical vapor deposition technology 3 N 4 。
6. The integrated AR display meta-system on-chip based on inverse design wavelength demultiplexing according to claim 1, wherein the meta-grating structure is a one-dimensional grating structure, forming two opposite optical channels, and two light beams of different wavelengths perpendicularly incident to the meta-grating structure enter the optical waveguide layer in opposite directions;
or the element grating structure is a two-dimensional grating, and two opposite optical channels are formed in each dimension.
7. The integrated AR display meta-system on a chip based on inverse design wavelength demultiplexing according to claim 1, wherein the nano-bricks in the nano-brick structure have the same length and width, are all in sub-wavelength scale, and have the same size.
8. The integrated AR display element system on chip based on inverse design wavelength demultiplexing according to any of claims 1 to 7, wherein an xoy coordinate system is established with the directions parallel to the two sides of the working plane of the optical waveguide layer as x-axis and y-axis, and the long and short axes of the element grating and the nanobelt are parallel to the working plane of the optical waveguide layer.
9. An AR holographic display method based on reverse design wavelength demultiplexing double-color channel is characterized in that based on the reverse design wavelength demultiplexing-based on-chip integrated AR display element system of claim 1, an element grating structure is used as a wavelength multiplexing input coupler, a nano-brick structure is used as a decoupler, and holographic display of two channels is realized.
10. An application of the on-chip integrated AR display meta-system based on inverse design wavelength demultiplexing, characterized in that the on-chip integrated AR display meta-system based on inverse design wavelength demultiplexing of claim 1 is integrated into an AR display device as a lens to realize AR display of multiple wavelength channels, and virtual holographic image information is projected into a real environment.
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| CN116907795B (en) * | 2023-06-26 | 2023-12-29 | 武汉量子技术研究院 | Multi-dimensional characterization method and device for leaky plasmon mode |
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