WO2023178838A1 - 一种二维光栅及其形成方法、光波导及近眼显示设备 - Google Patents

一种二维光栅及其形成方法、光波导及近眼显示设备 Download PDF

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WO2023178838A1
WO2023178838A1 PCT/CN2022/097624 CN2022097624W WO2023178838A1 WO 2023178838 A1 WO2023178838 A1 WO 2023178838A1 CN 2022097624 W CN2022097624 W CN 2022097624W WO 2023178838 A1 WO2023178838 A1 WO 2023178838A1
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Prior art keywords
dimensional grating
boundary line
shaped structure
strip
horizontal
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PCT/CN2022/097624
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English (en)
French (fr)
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宋强
郭晓明
马国斌
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深圳珑璟光电科技有限公司
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Publication of WO2023178838A1 publication Critical patent/WO2023178838A1/zh

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    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B5/00—Optical elements other than lenses
    • G02B5/18—Diffraction gratings
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
    • G02B27/01—Head-up displays
    • G02B27/0101—Head-up displays characterised by optical features
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/0001—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems
    • G02B6/0011—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form
    • G02B6/0013—Means for improving the coupling-in of light from the light source into the light guide
    • G02B6/0015—Means for improving the coupling-in of light from the light source into the light guide provided on the surface of the light guide or in the bulk of it
    • G02B6/0016—Grooves, prisms, gratings, scattering particles or rough surfaces
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/0001—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems
    • G02B6/0011—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form
    • G02B6/0013—Means for improving the coupling-in of light from the light source into the light guide
    • G02B6/0023—Means for improving the coupling-in of light from the light source into the light guide provided by one optical element, or plurality thereof, placed between the light guide and the light source, or around the light source
    • G02B6/0026—Wavelength selective element, sheet or layer, e.g. filter or grating
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/0001—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems
    • G02B6/0011—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form
    • G02B6/0033—Means for improving the coupling-out of light from the light guide
    • G02B6/005—Means for improving the coupling-out of light from the light guide provided by one optical element, or plurality thereof, placed on the light output side of the light guide

Definitions

  • Embodiments of the present application relate to the technical field of optical devices, and in particular to a two-dimensional grating and a method for forming the same, an optical waveguide and a near-eye display device.
  • Augmented Reality (AR) technology is a technology that integrates virtual information with the real world.
  • Augmented reality technology represented by augmented reality glasses, is currently emerging in various industries, especially in the security and industrial fields. It has greatly improved information interactive mode.
  • the relatively mature optical display solutions in augmented reality technology are mainly divided into prism solutions, birdbath solutions, free-form surface solutions and lightguide solutions. The first three solutions are larger in size, which limits their use in smart wearables, that is, augmented reality.
  • the optical waveguide solution is currently the best optical display solution in augmented reality glasses.
  • Optical waveguide solutions are divided into geometric waveguide solutions, embossed grating waveguide solutions and volume holographic waveguide solutions.
  • the geometric waveguide solution uses an array of coated semi-transparent semi-reflective mirrors to achieve the display of virtual information, but the field of view and eyesight of this solution are The dynamic range is limited, and the array lens will bring stripe effects to the picture, so the geometric waveguide solution cannot present the best display effect to the human eye.
  • Volume holographic waveguide solutions are currently limited in large-scale mass production.
  • the relief grating waveguide solution is currently the most researched technical solution due to the convenience of nanoimprinting, and has the advantages of a large field of view and a large eye movement range.
  • the current solutions for embossed grating waveguides mainly include optical waveguide solutions based on one-dimensional gratings and optical waveguide solutions based on two-dimensional gratings.
  • the two-dimensional grating waveguides are divided into coupling areas and outcoupling areas.
  • the outcoupling area uses two-dimensional gratings.
  • the structure takes into account both expansion and coupling functions.
  • the inventor found that there are at least the following problems in the above related technologies: in the current optical waveguide solution based on the two-dimensional grating structure, the two-dimensional grating structure used in the coupling area is usually a cylindrical structure and a rhombus structure. , these two structures have fewer adjustable parameters, so they are not conducive to the adjustment of coupling efficiency.
  • Embodiments of the present application provide a new type of two-dimensional grating and its formation method, optical waveguide and near-eye display device.
  • a two-dimensional grating which includes repeating units that are periodically tiled and arranged on the surface of the waveguide along the horizontal and vertical directions.
  • the repeating units include: A first recessed portion and a second recessed portion provided along a first horizontal line, and a strip-shaped portion recessed on the surface of the waveguide plate provided along a second horizontal line, the first horizontal line and the second horizontal line being parallel to the
  • the two virtual lines in the horizontal direction, the first recessed portion and the second recessed portion are arranged axially symmetrically along the central axis of the repeating unit, and the central axis is capable of bisecting the repeating unit and is perpendicular to
  • the virtual axes of the first horizontal line and the second horizontal line, the first recessed portion and the second recessed portion of the two adjacent repeating units in the horizontal direction form a drop-shaped structure, and the first recessed portion and the second recessed portion in the horizontal direction are adjacent to each other.
  • a two-dimensional grating which includes repeating units that are periodically tiled and arranged on the surface of the waveguide along the horizontal and vertical directions.
  • the repeating units include: A first protruding portion and a second protruding portion disposed along a first horizontal line, and a strip-shaped portion protruding from the surface of the waveguide plate disposed along a second horizontal line.
  • the first horizontal line and the second horizontal line are parallel.
  • the first protruding portion and the second protruding portion are arranged axially symmetrically along the central axis of the repeating unit, and the central axis is such that the repeating unit can be
  • An imaginary axis bisecting and perpendicular to the first horizontal line and the second horizontal line, the first convex portion and the second convex portion of two adjacent repeating units in the horizontal direction form a water drop shape Structure, a plurality of continuous strip-shaped parts in the horizontal direction constitute a strip-shaped structure, the strip-shaped structure is defined by a first boundary line and a second boundary line, the first boundary line and the second boundary line
  • the boundary lines are different polycurves.
  • the first boundary line is a sharp-convex multiple curve
  • the second boundary line is a plano-convex multiple curve
  • the first boundary line is a plano-convex multiple curve
  • the second boundary line is a sharp-convex multiple curve
  • the periodicity of the repeating unit in the horizontal direction is 200 nm-2 ⁇ m.
  • the characteristic size of the water drop-shaped structure in the vertical direction is 10 nm-2 ⁇ m.
  • the surface of the repeating unit is coated with a metal oxide film, and the thickness of the metal oxide film is 10 nm-200 nm.
  • embodiments of the present application provide a method for forming a two-dimensional grating, including: according to the demand for light coupling efficiency, determining the two parameters as described in the first aspect or the second aspect.
  • Optimization variables of the three-dimensional grating wherein the optimization variables include: the characteristic size of the water droplet-shaped structure, the relative position parameters of the water droplet-shaped structure and the strip-shaped structure arranged on the surface of the waveguide plate, and/or The curved surface shape of the first boundary line and the second boundary line; etching is performed on the waveguide sheet according to the optimized variables to form the two-dimensional grating.
  • embodiments of the present application also provide an optical waveguide, including: a waveguide plate; a coupling structure composed of a one-dimensional grating, which is disposed on the light incident side of the waveguide plate; and is composed of: The decoupling structure composed of the two-dimensional grating described in the first aspect or the second aspect is arranged on the light exit side of the waveguide plate.
  • embodiments of the present application also provide a near-eye display device, including: the optical waveguide as described in the fourth aspect.
  • the dimensional grating includes repeating units that are periodically tiled and arranged on the surface of the waveguide plate along the horizontal and vertical directions, and the repeating units include first recesses/protrusions and second recesses/protrusions arranged along the first horizontal line, and a strip-shaped portion disposed along the second horizontal line that is concave/convex on the surface of the waveguide sheet, the first concave/convex portion and the second concave portion that are adjacent to each other in the two adjacent repeating units in the horizontal direction.
  • the raised portion forms a drop-shaped structure
  • the strip-shaped structure is defined by a first boundary line and a second boundary line.
  • the first boundary line and the second boundary line are different multiple curves.
  • the two-dimensional The grating can be etched on the optical waveguide according to the requirements of light coupling efficiency. It can improve the adjustment freedom of the two-dimensional grating in the diffraction optical waveguide without increasing the processing difficulty, and can better control the coupling efficiency distribution. , achieving better exit pupil uniformity and field of view uniformity.
  • Figure 1 is a top view of a two-dimensional grating provided in Embodiment 1 of the present application;
  • Figure 2(a) is a top view of a single repeating unit in the two-dimensional grating shown in Figure 1;
  • Figure 2(b) is a top view of another two-dimensional grating provided in Embodiment 1 of the present application;
  • Figure 2(c) is a top view of a single repeating unit in the two-dimensional grating shown in Figure 2(b);
  • Figure 3(a) is the K vector diagram of the two-dimensional grating shown in Figure 1;
  • Figure 3(b) is the diffraction efficiency distribution diagram of the two-dimensional grating shown in Figure 1;
  • Figure 4 is a top view of a two-dimensional grating provided in Embodiment 2 of the present application.
  • Figure 5(a) is a top view of a single repeating unit in the two-dimensional grating shown in Figure 4;
  • Figure 5(b) is a top view of another two-dimensional grating provided in Embodiment 2 of the present application.
  • Figure 5(c) is a top view of a single repeating unit in the two-dimensional grating shown in Figure 5(b);
  • Figure 6(a) is the K vector diagram of the two-dimensional grating shown in Figure 4.
  • Figure 6(b) is the diffraction efficiency distribution diagram of the two-dimensional grating shown in Figure 4.
  • Figure 7 is a schematic flow chart of a two-dimensional grating forming method provided in Embodiment 3 of the present application.
  • Figure 8 is a schematic structural diagram of an optical waveguide provided in Embodiment 4 of the present application.
  • FIG. 9 is a schematic structural diagram of a near-eye display device provided in Embodiment 5 of the present application.
  • FIG. 1 shows a top view structure of a two-dimensional grating provided by this embodiment.
  • Figure 2(a) shows The structure of a single repeating unit in the two-dimensional grating shown in Figure 1 is shown.
  • the two-dimensional grating includes periodicity along the horizontal direction (the direction indicated by the dotted arrow in Figure 1) and the vertical direction (the direction parallel to the central axis l3).
  • Repeating units arranged flatly on the surface of the waveguide plate, the repeating units include a first recessed portion A1 and a second recessed portion A2 provided along the first horizontal line l1, and a recessed portion provided along the second horizontal line l2 in the waveguide plate.
  • the first horizontal line l1 and the second horizontal line l2 are two virtual lines parallel to the horizontal direction.
  • the white part in the figure represents the bulge
  • the black part represents the depression.
  • the first recessed portion A1 and the second recessed portion A2 are arranged axially symmetrically along the central axis l3 of the repeating unit.
  • the central axis l3 is capable of bisecting the repeating unit and is vertical.
  • the first recessed portion A1 and the second recessed portion A2 of the two adjacent repeating units in the horizontal direction form a water drop-shaped structure.
  • first boundary line S1 and a second boundary line S2 are different polynomial curves.
  • the first boundary line S1 is a sharp-convex multiple curve
  • the second boundary line S2 is a plano-convex multiple curve.
  • Figure 2(b) shows a top view structure of another two-dimensional grating provided by this embodiment.
  • Figure 2(c) shows the structure of a single repeating unit in the two-dimensional grating shown in Figure 2(b).
  • the first boundary line S1 is a plano-convex multiple curve
  • the second The boundary line S2 is a sharp convex multiple curve.
  • the convex shape of the first boundary line S1 and the second boundary line S2 can be set according to actual needs, and there is no need to be limited by this embodiment.
  • the repeating units are axially symmetrical figures with the central axis l3 as the axis of symmetry.
  • the vertical direction corresponding to the peak of the first boundary line S1 (pointed convex type) (that is, perpendicular to the direction of the dotted arrow in Figure 1, the central axis l3
  • the second boundary line S2 (plano-convex type) in the direction shown is also at the peak position.
  • the vertical direction corresponding to the peak of the second boundary line S2 (pointed convex type) (that is, perpendicular to the direction of the dotted arrow in Figure 1, the direction indicated by the central axis l3)
  • the first boundary line S1 (plano-convex type) is also at the peak position.
  • the peak of the sharp-convex boundary line maintains corresponding consistency with the peak of the flat-convex boundary line, that is, the sharp-convex boundary line is located on another flat-convex point in the vertical direction corresponding to the point at the peak.
  • the points on the boundary line of the pattern are also at the peak of the wave.
  • the period of the repeating unit along the horizontal direction is 200 nm-2 ⁇ m.
  • the characteristic size of the water droplet-shaped structure a in the vertical direction is 10 nm-2 ⁇ m.
  • the surface of the repeating unit is coated with a metal oxide film.
  • the thickness of the metal oxide film is 10 nm-200 nm.
  • the material used for the coating can be selected from the group consisting of titanium dioxide (TiO 2 ) and aluminum oxide (Al). 2 O 3 ) and other metal oxides.
  • the two-dimensional grating formed by the curve surface shape of the boundary line S1 and the second boundary line S2 can adjust the K vector of one or more diffraction orders of the incident light to realize the expansion of the light beam in the outcoupling area.
  • the coupling-out efficiency is relatively uniform.
  • the two-dimensional grating shown in Figure 1 can adjust the K vector of some diffraction orders as shown in Figure 3(a); it is used to realize the extended propagation of the beam in the outcoupling region.
  • the distribution of the diffraction efficiency in the vector direction of some diffraction orders is shown in Figure 3(b).
  • R0, R1, R2, R3, R4, and R5 in Figure 3(b) correspond to the front pass in Figure 3(a) respectively.
  • the repeating units are divided when the boundary lines have peaks and are axially symmetrical.
  • the repeating units are also It can be divided by the situation where the boundary line has a trough and is axially symmetrical, or it can be divided in other forms. Specifically, it can be set according to actual needs, and there is no need to stick to what is shown in Figure 2(a) and Figure 2(c) Qualification of the example.
  • the water drop-shaped structure a formed by the first recessed portion A1 and the second recessed portion A2 that are adjacent to each other is One side of the round head is disposed close to the strip-shaped portion A3, and the first recessed portion A1 and the second recessed portion A2 are not on the same vertical line as the wave crest of the strip-shaped portion A3 (that is, the water droplets The wave crests of the strip-shaped structure a and the strip-shaped structure are offset in the vertical direction).
  • the arrangement and position setting of the first recessed portion A1, the second recessed portion A2 and the strip-shaped portion A3 can also be other ways, and there is no need to be limited to this embodiment. restrictions.
  • FIG. 4 shows a top view structure of a two-dimensional grating provided by this embodiment.
  • Figure 5(a) is a diagram. The structure of a single repeating unit in the two-dimensional grating shown in 4.
  • the two-dimensional grating includes periodic tiling along the horizontal direction (the direction indicated by the dotted arrow in Figure 4) and the vertical direction (the direction parallel to the central axis l3).
  • the repeating units include a first protruding portion A4 and a second protruding portion A5 disposed along the first horizontal line l1, and a protruding portion protruding from the waveguide sheet disposed along the second horizontal line l2.
  • the first horizontal line l1 and the second horizontal line l2 are two virtual lines parallel to the horizontal direction. Among them, the white part in the figure represents the bulge, and the black part represents the depression.
  • the first protruding portion A4 and the second protruding portion A5 are arranged axially symmetrically along the central axis l3 of the repeating unit, and the central axis l3 is capable of bisecting the repeating unit. And perpendicular to the virtual axis of the first horizontal line l1 and the second horizontal line l2, the first convex part A4 and the second convex part A5 of the two adjacent repeating units in the horizontal direction are formed A drop-shaped structure a.
  • first boundary line S1 and a second boundary line S2 are different polynomial curves.
  • the first boundary line S1 is a sharp-convex multiple curve
  • the second boundary line S2 is a plano-convex multiple curve.
  • Figure 5(b) shows a top view structure of another two-dimensional grating provided by this embodiment.
  • Figure 5(c) shows the structure of the repeating unit in the two-dimensional grating shown in Figure 5(b).
  • the first boundary line S1 can also be a plano-convex multiple curve
  • the second boundary line S2 is a sharp convex multiple curve.
  • the convex shape of the first boundary line S1 and the second boundary line S2 can be set according to actual needs, and there is no need to be limited by this embodiment.
  • the repeating units are axially symmetrical figures with the central axis l3 as the axis of symmetry.
  • the vertical direction corresponding to the peak of the first boundary line S1 (pointed convex type) (that is, the direction perpendicular to the dotted arrow in Figure 1, the central axis l3
  • the second boundary line S2 (plano-convex type) in the direction shown is also at the peak position.
  • the vertical direction corresponding to the peak of the second boundary line S2 (pointed convex type) (that is, perpendicular to the direction of the dotted arrow in Figure 1, the direction indicated by the central axis l3)
  • the first boundary line S1 (plano-convex type) is also at the peak position.
  • the peak of the sharp-convex boundary line maintains corresponding consistency with the peak of the flat-convex boundary line, that is, the sharp-convex boundary line is located on another flat-convex point in the vertical direction corresponding to the point at the peak.
  • the points on the boundary line of the pattern are also at the peak of the wave.
  • the period of the repeating unit along the horizontal direction is 200 nm-2 ⁇ m.
  • the characteristic size of the water droplet-shaped structure a in the vertical direction is 10 nm-2 ⁇ m.
  • the surface of the repeating unit is coated with a metal oxide film.
  • the thickness of the metal oxide film is 10 nm-200 nm.
  • the material used for the coating can be selected from the group consisting of titanium dioxide (TiO 2 ) and aluminum oxide (Al). 2 O 3 ) and other metal oxides.
  • the two-dimensional grating formed by the curve surface shape of the boundary line S1 and the second boundary line S2 can adjust the K vector of one or more diffraction orders of the incident light to realize the expansion of the light beam in the outcoupling area.
  • the coupling-out efficiency is relatively uniform.
  • the two-dimensional grating shown in Figure 4 can adjust the K vector of some diffraction orders as shown in Figure 6(a); it is used to realize the extended propagation of the beam in the outcoupling region.
  • the distribution of the diffraction efficiency in the vector direction of some diffraction orders is shown in Figure 6(b).
  • R0, R1, R2, R3, R4, and R5 in Figure 6(b) correspond to the front pass in Figure 6(a) respectively.
  • the repeating units are divided when the boundary lines have peaks and are axially symmetrical. In some other embodiments, the repeating units are also It can be divided by the situation where the boundary line has a trough and is axially symmetrical, or it can be divided in other forms. Specifically, it can be set according to actual needs, and there is no need to stick to the figures in Figure 5(a) and Figure 5(c) Limitations of Examples.
  • the first protruding portion A4 and the second protruding portion A5 that are adjacent to each other form a water drop-shaped structure.
  • One side of the round head of a is disposed close to the strip-shaped portion A6, and the first protruding portion A4, the second protruding portion A5 and the peak of the strip-shaped portion A6 are not on the same vertical line.
  • the arrangement of the first protruding part A4, the second protruding part A5 and the strip-shaped part A6 can also be other arrangements, and there is no need to be limited to this embodiment. restrictions.
  • This embodiment provides a method for forming a two-dimensional grating. Please refer to Figure 7, which shows the flow of a method for forming a two-dimensional grating provided by this embodiment.
  • the forming method includes:
  • Step S11 According to the demand for light coupling efficiency, determine the optimization variables of the two-dimensional grating as described in Embodiment 1 or 2,
  • the optimization variables include: the characteristic size of the water droplet-shaped structure, the relative position parameters of the water droplet-shaped structure and the strip-shaped structure arranged on the surface of the waveguide sheet, the water droplet-shaped structure and the The height of the depression or protrusion of the strip structure relative to the surface of the waveguide plate, and/or the curved surface shape of the first boundary line and the second boundary line.
  • the characteristic dimensions of the water drop-shaped structure include the characteristic dimensions of the water drop-shaped structure in the horizontal direction and the characteristic dimensions of the water drop-shaped structure in the vertical direction; the water drop-shaped structure and the belt
  • the relative position parameters of the arrangement of the water drop-shaped structures on the surface of the waveguide include the spacing between the water drop-shaped structure and the strip-shaped structure in the vertical direction, and the spacing between two adjacent water drop-shaped structures in the horizontal direction.
  • the curved surface type represents the direction and bending amplitude of the curve, etc., for example, the curved surface type can be a sharp-convex type, a flat-convex type, etc.
  • Step S12 Perform etching on the waveguide plate according to the optimized variables to form the two-dimensional grating.
  • the size parameters in the structure of the two-dimensional grating can be optimized according to the diffraction efficiency of the optical waveguide required by the user, thereby obtaining the actual manufacturing parameters of the two-dimensional grating, that is, the optimization of the two-dimensional grating. variables; thus, the recessed portion is etched on the optical waveguide substrate according to the obtained optimized variables to form the required two-dimensional grating.
  • the method for forming a two-dimensional grating provided in this embodiment can be based on the diffraction efficiency requirements of the optical waveguide required by the user as shown in Figure 3(a) and Figure 3(b).
  • the size parameters in the structure of the two-dimensional grating in the example shown in Figure 1 are optimized to obtain the actual manufacturing parameters of the two-dimensional grating, that is, the optimization variables of the two-dimensional grating; thus, according to the obtained optimization variables, in the grating
  • the recessed part is etched on the waveguide substrate, that is, the black part in FIG. 1 and FIG. 2(a) is etched to form a two-dimensional grating as shown in FIG. 1 in Embodiment 1.
  • the two-dimensional grating in the example shown in Figure 4 of Embodiment 2 The size parameters in the structure are optimized to obtain the actual manufacturing parameters of the two-dimensional grating, that is, the optimized variables of the two-dimensional grating. Therefore, according to the obtained optimization variables, the recessed part is etched on the optical waveguide substrate, that is, the etching operation is performed on the black part in Figure 4 and Figure 5 (a), to form a structure as shown in Figure 4 in Embodiment 2. two-dimensional grating.
  • This embodiment provides an optical waveguide.
  • the optical waveguide 10 shown includes: a waveguide plate 11; a coupling element composed of a one-dimensional grating.
  • the structure 12 is arranged on the light incident side of the waveguide plate 11; the coupling structure 13 composed of the two-dimensional grating as described in Embodiment 1 or 2 is arranged on the light exit side of the waveguide plate 11.
  • the coupling structure 12 can be a rectangular grating, a tilted grating, a trapezoidal grating, an echelon grating, a holographic grating or other one-dimensional gratings. Specifically, the coupling structure 12 can diffractively couple the projection light of the optical machine to the waveguide plate 11 Total reflection propagation in the direction of the coupling-out structure 13 can be set according to actual needs.
  • the coupling-out structure 13 is composed of a two-dimensional grating as described in Embodiment 1 or 2. This two-dimensional grating is easy to process and is conducive to adjusting the coupling efficiency. Specifically, please refer to Embodiment 1 or 2 and the following. As shown in the drawings, which will not be described in detail here, the decoupling area 13 can diffuse and propagate light, and couple part of the light out of the waveguide substrate 11 into the human eye, thereby achieving pupil dilation display.
  • This embodiment provides a near-eye display device. Please refer to FIG. 9 , which shows the structure of a near-eye display device provided by this embodiment.
  • the near-eye display device 100 includes: an optical waveguide as described in Embodiment 4. 10.
  • the near-eye display device 100 provided in this embodiment uses the two-dimensional grating shown in Embodiment 1 or 2 of the present application as the coupling structure in the optical waveguide 10.
  • This two-dimensional grating has more optimization variables and can Perform multi-parameter control to adjust the diffraction efficiency.
  • Embodiments of the present application provide a two-dimensional grating and a method for forming the same, an optical waveguide, and a near-eye display device.
  • the two-dimensional grating includes repeating units that are periodically tiled and arranged on the surface of the waveguide plate along the horizontal and vertical directions.
  • the repeating unit includes a first recessed/protruded portion and a second recessed/protruded portion provided along the first horizontal line, and a recessed/protruded strip portion provided on the surface of the waveguide plate along the second horizontal line, horizontally
  • the first recess/protrusion and the second recess/protrusion in two adjacent repeating units in the direction form a drop-shaped structure, and the band-shaped structure is defined by the first boundary line and the second boundary line.
  • the first boundary line and the second boundary line are different polynomial curves.
  • the two-dimensional grating can be etched and formed on the optical waveguide according to the requirements of light coupling efficiency. It can improve the adjustment freedom of the two-dimensional grating in the diffractive optical waveguide without increasing the processing difficulty, and can better control the coupling. Exit efficiency distribution to achieve better exit pupil uniformity and field of view uniformity.
  • the device embodiments described above are only illustrative.
  • the units described as separate components may or may not be physically separated.
  • the components shown as units may or may not be physically separate.
  • the unit can be located in one place, or it can be distributed across multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment.
  • each embodiment can be implemented by means of software plus a general hardware platform, and of course, it can also be implemented by hardware.
  • the programs can be stored in computer-readable storage media. When the programs are executed, When doing so, it may include the processes of the above method embodiments.
  • the storage medium can be a magnetic disk, an optical disk, a read-only memory (Read-Only Memory, ROM) or a random access memory (Random Access Memory, RAM), etc.

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  • Optical Integrated Circuits (AREA)

Abstract

本申请实施例涉及光学器件技术领域，公开了一种二维光栅及其形成方法、光波导及近眼显示设备，二维光栅包括沿水平方向和竖直方向周期性平铺排列在波导片表面的重复单元，重复单元包括沿第一水平线设置的第一凹陷/凸起部和第二凹陷/凸起部、沿第二水平线设置的凹设/凸设于波导片表面的带状部，水平方向上相邻两个重复单元中第一凹陷/凸起部和第二凹陷/凸起部构成一个水滴状结构，带状结构由不同多次曲线的第一边界线和第二边界线限定而成，二维光栅根据光线耦出效率的需求在光波导上刻蚀形成，在不增加加工难度的前提下提高衍射光波导中的二维光栅的调节自由度，以控制耦出效率分布，实现更好的出瞳均匀性和视场均匀性。

Description

一种二维光栅及其形成方法、光波导及近眼显示设备
相关申请的交叉参考
本申请要求于2022年3月23日提交中国专利局，申请号为202210289417.9，发明名称为“一种二维光栅及其形成方法、光波导及近眼显示设备”的中国专利申请的优先权，其全部内容通过引用结合在本申请中。
技术领域
本申请实施例涉及光学器件技术领域，特别涉及一种二维光栅及其形成方法、光波导及近眼显示设备。
背景技术
增强现实(Augmented Reality，AR)技术是将虚拟信息与现实世界相互融合的技术，以增强现实眼镜为代表的增强现实技术目前在各个行业开始兴起，尤其在安防和工业领域，其大大改进了信息交互方式。目前比较成熟的增强现实技术中的光学显示方案主要分为棱镜方案、birdbath方案、自由曲面方案和光波导(Lightguide)方案，前三种方案体积较大，限制了其在智能穿戴方面，即增强现实眼镜方面的应用，光波导方案是目前增强现实眼镜中最佳的光学显示方案。
光波导方案又分为几何波导方案、浮雕光栅波导方案和体全息波导方案，其中，几何波导方案是使用阵列的镀膜半透半反射镜来达到虚拟信息的显示，但是该方案的视场和眼动范围受限，而且阵列镜片会给画面带来条纹效果，所以几何波导方案无法给人眼呈现最佳的显示效果。体全息波导方案目前在大规模量产上受到了限制。浮雕光栅波导方案由于纳米压印的便利性是目前研究最多的技术方案，具有大视场和大眼动 范围的优势。
其中，目前浮雕光栅波导的方案路径主要有基于一维光栅的光波导方案和基于二维光栅的光波导方案，二维光栅波导分为耦入区域和耦出区域，耦出区域使用二维光栅结构兼顾了扩展和耦出的功能。
在实现本申请实施例过程中，发明人发现以上相关技术中至少存在如下问题：目前基于二维光栅结构的光波导方案中，在耦出区域使用的二维光栅结构通常为圆柱结构和菱形结构，这两种结构可调节参数较少，所以不利于耦出效率的调节。
发明内容
本申请实施例提供了一种新型的二维光栅及其形成方法、光波导及近眼显示设备。
本申请实施例的目的是通过如下技术方案实现的：
为解决上述技术问题，第一方面，本申请实施例中提供了一种二维光栅，包括沿水平方向和竖直方向周期性平铺排列在波导片表面的重复单元，所述重复单元包括沿第一水平线设置的第一凹陷部和第二凹陷部，以及沿第二水平线设置的凹设于所述波导片表面的带状部，所述第一水平线和所述第二水平线为平行于所述水平方向的两条虚拟线，所述第一凹陷部和所述第二凹陷部沿所述重复单元的中心轴呈轴对称设置，所述中心轴为能够将所述重复单元平分且垂直于所述第一水平线和所述第二水平线的虚拟轴线，水平方向上相邻两个所述重复单元中、紧挨的第一凹陷部和第二凹陷部构成一个水滴状结构，水平方向上的连续若干个所述带状部构成一带状结构，所述带状结构由第一边界线和第二边界线限定而成，所述第一边界线和所述第二边界线为不同的多次曲线。
为解决上述技术问题，第二方面，本申请实施例中提供了一种二维光栅，包括沿水平方向和竖直方向周期性平铺排列在波导片表面的重复 单元，所述重复单元包括沿第一水平线设置的第一凸起部和第二凸起部，以及沿第二水平线设置的凸设于所述波导片表面的带状部，所述第一水平线和所述第二水平线为平行于所述水平方向的两条虚拟线，所述第一凸起部和所述第二凸起部沿所述重复单元的中心轴呈轴对称设置，所述中心轴为能够将所述重复单元平分且垂直于所述第一水平线和所述第二水平线的虚拟轴线，水平方向上相邻两个所述重复单元中、紧挨的第一凸起部和第二凸起部构成一个水滴状结构，水平方向上的连续若干个所述带状部构成一带状结构，所述带状结构由第一边界线和第二边界线限定而成，所述第一边界线和所述第二边界线为不同的多次曲线。
在一些实施例中，在所述重复单元内，所述第一边界线为尖凸型多次曲线，所述第二边界线为平凸型多次曲线。
在一些实施例中，在所述重复单元内，所述第一边界线为平凸型多次曲线，所述第二边界线为尖凸型多次曲线。
在一些实施例中，所述重复单元沿水平方向的周期为200nm-2μm。
在一些实施例中，所述水滴状结构在竖直方向上的特征尺寸为10nm-2μm。
在一些实施例中，所述重复单元的表面镀设有金属氧化膜，所述金属氧化膜的厚度为10nm-200nm。
为解决上述技术问题，第三方面，本申请实施例中提供了一种二维光栅的形成方法，包括：根据对光线耦出效率的需求，确定如第一方面或第二方面所述的二维光栅的优化变量，其中，所述优化变量包括：所述水滴状结构的特征尺寸、所述水滴状结构和所述带状结构在所述波导片表面上排列的相对位置参数、和/或所述第一边界线和所述第二边界线的曲线面型；根据所述优化变量在波导片上进行刻蚀作业以形成所述二维光栅。
为解决上述技术问题，第四方面，本申请实施例还提供了一种光波导，包括：波导片；由一维光栅构成的耦入结构，设置在所述波导片的入光侧；由如第一方面或第二方面所述的二维光栅构成的耦出结构，设置在所述波导片的出光侧。
为解决上述技术问题，第五方面，本申请实施例还提供了一种近眼显示设备，包括：如第四方面所述的光波导。
与现有技术相比，本申请的有益效果是：区别于现有技术的情况，本申请实施例中提供了一种新型的二维光栅及其形成方法、光波导及近眼显示设备，该二维光栅包括沿水平方向和竖直方向周期性平铺排列在波导片表面的重复单元，所述重复单元包括沿第一水平线设置的第一凹陷/凸起部和第二凹陷/凸起部，以及沿第二水平线设置的凹设/凸设于所述波导片表面的带状部，水平方向上相邻两个所述重复单元中、紧挨的第一凹陷/凸起部和第二凹陷/凸起部构成一个水滴状结构，带状结构由第一边界线和第二边界线限定而成，所述第一边界线和所述第二边界线为不同的多次曲线，该二维光栅可以根据光线耦出效率的需求在光波导上刻蚀形成，能够在不增加加工难度的前提下，提高衍射光波导中的二维光栅的调节自由度，可以更好的控制耦出效率分布，实现更好的出瞳均匀性和视场均匀性。
附图说明
一个或多个实施例中通过与之对应的附图中的图片进行示例性说明，这些示例性说明并不构成对实施例的限定，附图中具有相同参考数字标号的元件/模块和步骤表示为类似的元件/模块和步骤，除非有特别申明，附图中的图不构成比例限制。
图1是本申请实施例一提供的一种二维光栅的俯视图；
图2(a)是图1所示二维光栅中的单个重复单元的俯视图；
图2(b)是本申请实施例一提供的另一种二维光栅的俯视图；
图2(c)是图2(b)所示二维光栅中的单个重复单元的俯视图；
图3(a)是图1所示二维光栅的K矢量图；
图3(b)是图1所示二维光栅的衍射效率分布图；
图4是本申请实施例二提供的一种二维光栅的俯视图；
图5(a)是图4所示二维光栅中的单个重复单元的俯视图；
图5(b)是本申请实施例二提供的另一种二维光栅的俯视图；
图5(c)是图5(b)所示二维光栅中的单个重复单元的俯视图；
图6(a)是图4所示二维光栅的K矢量图；
图6(b)是图4所示二维光栅的衍射效率分布图；
图7是本申请实施例三提供的一种二维光栅的形成方法的流程示意图；
图8是本申请实施例四提供的一种光波导的结构示意图；
图9是本申请实施例五提供的一种近眼显示设备的结构示意图。
具体实施方式
下面结合具体实施例对本申请进行详细说明。以下实施例将有助于本领域的技术人员进一步理解本申请，但不以任何形式限制本申请。应当指出的是，对本领域的普通技术人员来说，在不脱离本申请构思的前提下，还可以做出若干变形和改进。这些都属于本申请的保护范围。
为了使本申请的目的、技术方案及优点更加清楚明白，以下结合附图及实施例，对本申请进行进一步详细说明。应当理解，此处所描述的具体实施例仅用以解释本申请，并不用于限定本申请。
需要说明的是，如果不冲突，本申请实施例中的各个特征可以相互结合，均在本申请的保护范围之内。另外，虽然在装置示意图中进行了 功能模块划分，在流程图中示出了逻辑顺序，但是在某些情况下，可以以不同于装置中的模块划分，或流程图中的顺序执行所示出或描述的步骤。此外，本文所采用的“第一”、“第二”等字样并不对数据和执行次序进行限定，仅是对功能和作用基本相同的相同项或相似项进行区分。
除非另有定义，本说明书所使用的所有的技术和科学术语与属于本申请的技术领域的技术人员通常理解的含义相同。本说明书中在本申请的说明书中所使用的术语只是为了描述具体的实施方式的目的，不是用于限制本申请。本说明书所使用的术语“和/或”包括一个或多个相关的所列项目的任意的和所有的组合。
此外，下面所描述的本申请各个实施方式中所涉及到的技术特征只要彼此之间未构成冲突就可以相互组合。
具体地，下面结合附图，对本申请实施例作进一步阐述；应当理解的是，二维光栅及其重复单元的结构示意图中，图中的阴影部分为光栅结构。
实施例一
本实施例提供了一种二维光栅，请参见图1和图2(a)，其中，图1示出了本实施例提供的一种二维光栅的俯视结构，图2(a)示出了图1所示二维光栅中的单个重复单元的结构，所述二维光栅包括沿水平方向(图1中虚线箭头所示方向)和竖直方向(平行于中心轴l3的方向)周期性平铺排列在波导片表面的重复单元，所述重复单元包括沿第一水平线l1设置的第一凹陷部A1和第二凹陷部A2，以及沿第二水平线l2设置的凹设于所述波导片表面的带状部A3，所述第一水平线l1和所述第二水平线l2为平行于所述水平方向的两条虚拟线。其中，图中白色部分表示凸起，黑色部分表示凹陷。
在本实施例中，所述第一凹陷部A1和所述第二凹陷部A2沿所述重复单元的中心轴l3呈轴对称设置，所述中心轴l3为能够将所述重复单元平分且垂直于所述第一水平线l1和所述第二水平线l2的虚拟轴线，水平方向上相邻两个所述重复单元中、紧挨的第一凹陷部A1和第二凹陷部A2构成一个水滴状结构a。
在本实施例中，水平方向上的连续若干个所述带状部A3构成一带状结构，所述带状结构由第一边界线S1和第二边界线S2限定而成，所述第一边界线S1和所述第二边界线S2为不同的多次曲线。
在本实施例图2(a)所示示例中，在所述重复单元内，所述第一边界线S1为尖凸型多次曲线，所述第二边界线S2为平凸型多次曲线。在其他的一些实施例中，请参见图2(b)、图2(c)，图2(b)示出了本实施例提供的另一种二维光栅的俯视结构，图2(c)示出了图2(b)所示二维光栅中的单个重复单元的结构，在所述重复单元内，还可以是所述第一边界线S1为平凸型多次曲线，所述第二边界线S2为尖凸型多次曲线，具体地，可根据实际需要设置所述第一边界线S1和所述第二边界线S2的凸面型，不需要拘泥于本实施例的限定。优选地，在图2(a)和图2(c)所示示例中，所述重复单元均是以中心轴l3为对称轴的轴对称图形。
且有，在图2(a)所示示例中，所述第一边界线S1(尖凸型)的波峰处对应的竖直方向(即垂直于图1中虚线箭头的方向，中心轴l3所示方向)上的所述第二边界线S2(平凸型)也处于波峰位置。在图2(c)所示示例中，所述第二边界线S2(尖凸型)的波峰处对应的竖直方向(即垂直于图1中虚线箭头的方向，中心轴l3所示方向)上的所述第一边界线S1(平凸型)也处于波峰位置。优选地，尖凸型的边界线的波峰与平凸型的边界线的波峰保持相应的一致性，也即，尖凸型的边 界线处于波峰处的点对应的竖直方向上的另一平凸型的边界线上的点也处于波峰位置。
在一些实施例中，所述重复单元沿水平方向(图1中虚线箭头所示方向)的周期为200nm-2μm。在一些实施例中，所述水滴状结构a的在竖直方向上的特征尺寸为10nm-2μm。在一些实施例中，所述重复单元的表面镀设有金属氧化膜，所述金属氧化膜的厚度为10nm-200nm，镀膜用的材料可以选自如二氧化钛(TiO 2)和三氧化二铝(Al 2O 3)等金属氧化物中的至少一种。
在本实施例中，通过调节所述水滴状结构a的特征尺寸、所述水滴状结构a和所述带状结构在所述波导片表面上排列的相对位置参数、和/或所述第一边界线S1和所述第二边界线S2的曲线面型等，形成的二维光栅可以对入射的光线进行一个或多个衍射级次的K矢量的调节，用于实现光束在耦出区域扩展传播时，耦出效率较为均匀。
具体的，周期为800nmx462nm时，图1所示的二维光栅可以实现对如图3(a)所示部分衍射级次的K矢量的调节；其用于实现光束在耦出区域的扩展传播时，部分衍射级次的矢量方向的衍射效率的分布如图3(b)所示，图3(b)中的R0、R1、R2、R3、R4、R5分别对应图3(a)中的前传级次0、扩展级次1、扩展级次2、扩展级次3、扩展级次4、回传级次5。
需要说明的是，在图2(a)和图2(c)所示示例中，重复单元以边界线出现波峰且轴对称的情况来划分，在其他的一些实施例中，所述重复单元也可以以边界线出现波谷且轴对称的情况来划分，或者，以其他的形式来划分，具体地，可根据实际需要进行设置，不需要拘泥于图2(a)和图2(c)所示示例的限定。
还需要说明的是，在本实施例中，水平方向上相邻两个所述重复单 元中、紧挨的所述第一凹陷部A1和所述第二凹陷部A2构成的水滴状结构a的圆头的一侧靠近所述带状部A3设置，且所述第一凹陷部A1和所述第二凹陷部A2与所述带状部A3的波峰不在同一竖直线上(即所述水滴状结构a与所述带状结构的波峰在竖直方向上错位设置)。在其他的一些实施例中，所述第一凹陷部A1、所述第二凹陷部A2和所述带状部A3的排列方式和位置设置也可以是其他的方式，不需要拘泥于本实施例的限定。
实施例二
本实施例提供了一种二维光栅，请参见图4和图5(a)，其中，图4示出了本实施例提供的一种二维光栅的俯视结构，图5(a)是图4所示二维光栅中的单个重复单元的结构，所述二维光栅包括沿水平方向(图4中虚线箭头所示方向)和竖直方向(平行于中心轴l3的方向)周期性平铺排列在波导片表面的重复单元，所述重复单元包括沿第一水平线l1设置的第一凸起部A4和第二凸起部A5，以及沿第二水平线l2设置的凸设于所述波导片表面的带状部A6，所述第一水平线l1和所述第二水平线l2为平行于所述水平方向的两条虚拟线。其中，图中白色部分表示凸起，黑色部分表示凹陷。
在本实施例中，所述第一凸起部A4和所述第二凸起部A5沿所述重复单元的中心轴l3呈轴对称设置，所述中心轴l3为能够将所述重复单元平分且垂直于所述第一水平线l1和所述第二水平线l2的虚拟轴线，水平方向上相邻两个所述重复单元中、紧挨的第一凸起部A4和第二凸起部A5构成一个水滴状结构a。
在本实施例中，水平方向上的连续若干个所述带状部A3构成一带状结构，所述带状结构由第一边界线S1和第二边界线S2限定而成，所 述第一边界线S1和所述第二边界线S2为不同的多次曲线。
在本实施例图5(a)所示示例中，在所述重复单元内，所述第一边界线S1为尖凸型多次曲线，所述第二边界线S2为平凸型多次曲线。在其他的一些实施例中，请参见图5(b)、图5(c)，图5(b)示出了本实施例提供的另一种二维光栅的俯视结构，图5(c)示出了图5(b)所示二维光栅中重复单元的结构，在所述重复单元内，还可以是所述第一边界线S1为平凸型多次曲线，所述第二边界线S2为尖凸型多次曲线，具体地，可根据实际需要设置所述第一边界线S1和所述第二边界线S2的凸面型，不需要拘泥于本实施例的限定。优选地，在图5(a)和图5(c)所示示例中，所述重复单元均是以中心轴l3为对称轴的轴对称图形。
且有，在图5(a)所示示例中，所述第一边界线S1(尖凸型)的波峰处对应的竖直方向(即垂直于图1中虚线箭头的方向，中心轴l3所示方向)上的所述第二边界线S2(平凸型)也处于波峰位置。在图5(c)所示示例中，所述第二边界线S2(尖凸型)的波峰处对应的竖直方向(即垂直于图1中虚线箭头的方向，中心轴l3所示方向)上的所述第一边界线S1(平凸型)也处于波峰位置。优选地，尖凸型的边界线的波峰与平凸型的边界线的波峰保持相应的一致性，也即，尖凸型的边界线处于波峰处的点对应的竖直方向上的另一平凸型的边界线上的点也处于波峰位置。
在一些实施例中，所述重复单元沿水平方向(图4中虚线箭头所示方向)的周期为200nm-2μm。在一些实施例中，所述水滴状结构a在竖直方向上的特征尺寸为10nm-2μm。在一些实施例中，所述重复单元的表面镀设有金属氧化膜，所述金属氧化膜的厚度为10nm-200nm，镀膜用的材料可以选自如二氧化钛(TiO 2)和三氧化二铝(Al 2O 3)等金属氧化 物中的至少一种。
在本实施例中，通过调节所述水滴状结构a的特征尺寸、所述水滴状结构a和所述带状结构在所述波导片表面上排列的相对位置参数、和/或所述第一边界线S1和所述第二边界线S2的曲线面型等，形成的二维光栅可以对入射的光线进行一个或多个衍射级次的K矢量的调节，用于实现光束在耦出区域扩展传播时，耦出效率较为均匀。具体的，周期为800nmx462nm时，图4所示的二维光栅可以实现对如图6(a)所示部分衍射级次的K矢量的调节；其用于实现光束在耦出区域的扩展传播时，部分衍射级次的矢量方向的衍射效率的分布如图6(b)所示，图6(b)中的R0、R1、R2、R3、R4、R5分别对应图6(a)中的前传级次0、扩展级次1、扩展级次2、扩展级次3、扩展级次4、回传级次5。
需要说明的是，在图5(a)和图5(c)所示示例中，重复单元以边界线出现波峰且轴对称的情况来划分，在其他的一些实施例中，所述重复单元也可以以边界线出现波谷且轴对称的情况来划分，或者，以其他的形式来划分，具体地，可根据实际需要进行设置，不需要拘泥于图5(a)和图5(c)中的实施例的限定。
还需要说明的是，在本实施例中，水平方向上相邻两个所述重复单元中、紧挨的所述第一凸起部A4和所述第二凸起部A5构成的水滴状结构a的圆头的一侧靠近所述带状部A6设置，且所述第一凸起部A4和所述第二凸起部A5与所述带状部A6的波峰不在同一竖直线上。在其他的一些实施例中，所述第一凸起部A4、所述第二凸起部A5和所述带状部A6的排列方式也可以是其他的排列方式，不需要拘泥于本实施例的限定。
实施例三
本实施例提供了一种二维光栅的形成方法，请参见图7，其示出了本实施例提供的一种二维光栅的形成方法的流程，所述形成方法包括：
步骤S11：根据对光线耦出效率的需求，确定如实施例一或实施例二所述的二维光栅的优化变量，
其中，所述优化变量包括：所述水滴状结构的特征尺寸、所述水滴状结构和所述带状结构在所述波导片表面上排列的相对位置参数、所述水滴状结构和和所述带状结构相对所述波导片表面凹陷或凸起的高度、和/或所述第一边界线和所述第二边界线的曲线面型。
应当理解的是，所述水滴状结构的特征尺寸包括所述水滴状结构在水平方向上的特征尺寸、所述水滴状结构在竖直方向上的特征尺寸；所述水滴状结构和所述带状结构在所述波导片表面上排列的相对位置参数包括所述水滴状结构和所述带状结构在竖直方向上的间距、水平方向上相邻两个所述水滴状结构之间的间距、所述水滴状结构的圆头与所述带状结构的相对位置(如靠近设置或远离设置)、所述水滴状结构和所述带状结构的波峰在竖直方向上的相对位置(如错位设置或正对设置)等；所述曲线面型表示曲线弯曲的方向及弯曲幅度等，例如，所述曲线面型可为尖凸型、平凸型等。示例性的，请参阅图1和图2(a)、图2(b)和图2(c)、图4和图5(a)、图5(b)和图5(c)，所述水滴状结构a和所述带状结构在竖直方向上的间距为d。
步骤S12：根据所述优化变量在波导片上进行刻蚀作业以形成所述二维光栅。
具体的，可根据用户所需要的光波导的衍射效率的的需求，对二维光栅的结构中的尺寸参数进行优化，从而得到二维光栅的实际制造参数，即所述的二维光栅的优化变量；从而，根据得到的优化变量在光波导基底上刻蚀所述凹陷的部分，以形成所需的二维光栅。
示例性的，本实施例提供的二维光栅的形成方法，可根据用户所需要的光波导的如图3(a)和图3(b)所示的衍射效率的的需求，对如实施例一图1所示示例中的二维光栅的结构中的尺寸参数进行优化，从而得到二维光栅的实际制造参数，即所述的二维光栅的优化变量；从而，根据得到的优化变量在光波导基底上刻蚀所述凹陷的部分，也即在图1、图2(a)中黑色部分进行刻蚀作业，以形成如实施例一中图1所示的二维光栅。
另一示例性的，根据用户所需要的光波导的如图6(a)和图6(b)所示的衍射效率的的需求，对如实施例二图4所示示例中的二维光栅的结构中的尺寸参数进行优化，从而得到二维光栅的实际制造参数，即所述的二维光栅的优化变量。从而，根据得到的优化变量在光波导基底上刻蚀所述凹陷的部分，也即在图4、图5(a)中黑色部分进行刻蚀作业，以形成如实施例二中图4所示的二维光栅。
实施例四
本实施例提供了一种光波导，请参见图8，其示出了本实施例提供的一种光波导的结构，所示光波导10包括：波导片11；由一维光栅构成的耦入结构12，设置在所述波导片11的入光侧；由如实施例一或实施例二所述的二维光栅构成的耦出结构13，设置在所述波导片11的出光侧。
所述耦入结构12可以为矩形光栅、倾斜光栅、梯形光栅、阶梯光栅、全息光栅或其它一维光栅，具体地，所述耦入结构12可以将光机的投影光线衍射耦合到波导片11内朝耦出结构13的方向全反射传播，可根据实际需要进行设置。
所述耦出结构13由如实施例一或实施例二所述的二维光栅构成， 该二维光栅易于加工，利于调节耦出效率，具体地，请参见实施例一或实施例二及其附图所示，此处不再详述，所述耦出区域13能够将光线扩散传播，并将部分光线耦出波导基底11进入人眼，从而实现扩瞳显示。
实施例五
本实施例提供了一种近眼显示设备，请参见图9，其示出了本实施例提供的一种近眼显示设备的结构，所述近眼显示设备100包括：如实施例四所述的光波导10。
本实施例提供的近眼显示设备100，由于其光波导10采用的是本申请实施例一或实施例二所示的二维光栅作为耦出结构，该二维光栅具有更多的优化变量，可进行多参数调控来实现对衍射效率的调整。
本申请实施例中提供了一种二维光栅及其形成方法、光波导及近眼显示设备，该二维光栅包括沿水平方向和竖直方向周期性平铺排列在波导片表面的重复单元，所述重复单元包括沿第一水平线设置的第一凹陷/凸起部和第二凹陷/凸起部，以及沿第二水平线设置的凹设/凸设于所述波导片表面的带状部，水平方向上相邻两个所述重复单元中、紧挨的第一凹陷/凸起部和第二凹陷/凸起部构成一个水滴状结构，带状结构由第一边界线和第二边界线限定而成，所述第一边界线和所述第二边界线为不同的多次曲线。该二维光栅可以根据光线耦出效率的需求在光波导上刻蚀形成，能够在不增加加工难度的前提下，提高衍射光波导中的二维光栅的调节自由度，可以更好的控制耦出效率分布，实现更好的出瞳均匀性和视场均匀性。
需要说明的是，以上所描述的装置实施例仅仅是示意性的，其中所 述作为分离部件说明的单元可以是或者也可以不是物理上分开的，作为单元显示的部件可以是或者也可以不是物理单元，即可以位于一个地方，或者也可以分布到多个网络单元上。可以根据实际的需要选择其中的部分或者全部模块来实现本实施例方案的目的。
通过以上的实施方式的描述，本领域普通技术人员可以清楚地了解到各实施方式可借助软件加通用硬件平台的方式来实现，当然也可以通过硬件。本领域普通技术人员可以理解实现上述实施例方法中的全部或部分流程是可以通过计算机程序来指令相关的硬件来完成，所述的程序可存储于计算机可读取存储介质中，该程序在执行时，可包括如上述各方法的实施例的流程。其中，所述的存储介质可为磁碟、光盘、只读存储记忆体(Read-Only Memory,ROM)或随机存储记忆体(Random Access Memory,RAM)等。
最后应说明的是：以上实施例仅用以说明本申请的技术方案，而非对其限制；在本申请的思路下，以上实施例或者不同实施例中的技术特征之间也可以进行组合，步骤可以以任意顺序实现，并存在如上所述的本申请的不同方面的许多其它变化，为了简明，它们没有在细节中提供；尽管参照前述实施例对本申请进行了详细的说明，本领域的普通技术人员应当理解：其依然可以对前述各实施例所记载的技术方案进行修改，或者对其中部分技术特征进行等同替换；而这些修改或者替换，并不使相应技术方案的本质脱离本申请各实施例技术方案的范围。

Claims (10)

  1. 一种二维光栅，其特征在于，包括沿水平方向和竖直方向周期性平铺排列在波导片表面的重复单元，所述重复单元包括沿第一水平线设置的第一凹陷部和第二凹陷部，以及沿第二水平线设置的凹设于所述波导片表面的带状部，所述第一水平线和所述第二水平线为平行于所述水平方向的两条虚拟线，
    所述第一凹陷部和所述第二凹陷部沿所述重复单元的中心轴呈轴对称设置，所述中心轴为能够将所述重复单元平分且垂直于所述第一水平线和所述第二水平线的虚拟轴线，水平方向上相邻两个所述重复单元中、紧挨的第一凹陷部和第二凹陷部构成一个水滴状结构，
    水平方向上的连续若干个所述带状部构成一带状结构，所述带状结构由第一边界线和第二边界线限定而成，所述第一边界线和所述第二边界线为不同的多次曲线。
  2. 一种二维光栅，其特征在于，包括沿水平方向和竖直方向周期性平铺排列在波导片表面的重复单元，所述重复单元包括沿第一水平线设置的第一凸起部和第二凸起部，以及沿第二水平线设置的凸设于所述波导片表面的带状部，所述第一水平线和所述第二水平线为平行于所述水平方向的两条虚拟线，
    所述第一凸起部和所述第二凸起部沿所述重复单元的中心轴呈轴对称设置，所述中心轴为能够将所述重复单元平分且垂直于所述第一水平线和所述第二水平线的虚拟轴线，水平方向上相邻两个所述重复单元中、紧挨的第一凸起部和第二凸起部构成一个水滴状结构，
    水平方向上的连续若干个所述带状部构成一带状结构，所述带状结 构由第一边界线和第二边界线限定而成，所述第一边界线和所述第二边界线为不同的多次曲线。
  3. 根据权利要求1或2所述的二维光栅，其特征在于，
    在所述重复单元内，所述第一边界线为尖凸型多次曲线，所述第二边界线为平凸型多次曲线。
  4. 根据权利要求1或2所述的二维光栅，其特征在于，
    在所述重复单元内，所述第一边界线为平凸型多次曲线，所述第二边界线为尖凸型多次曲线。
  5. 根据权利要求1或2所述的二维光栅，其特征在于，
    所述重复单元沿水平方向的周期为200nm-2μm。
  6. 根据权利要求1或2所述的二维光栅，其特征在于，
    所述水滴状结构在竖直方向上的特征尺寸为10nm-2μm。
  7. 根据权利要求1或2所述的二维光栅，其特征在于，
    所述重复单元的表面镀设有金属氧化膜，所述金属氧化膜的厚度为10nm-200nm。
  8. 一种二维光栅的形成方法，其特征在于，包括：
    根据对光线耦出效率的需求，确定如权利要求1-7任一项所述的二维光栅的优化变量，
    其中，所述优化变量包括：所述水滴状结构的特征尺寸、所述水滴 状结构和所述带状结构在所述波导片表面上排列的相对位置参数、所述水滴状结构和所述带状结构相对所述波导片表面凹陷或凸起的高度、和/或所述第一边界线和所述第二边界线的曲线面型；
    根据所述优化变量在波导片上进行刻蚀作业以形成所述二维光栅。
  9. 一种光波导，其特征在于，包括：
    波导片；
    由一维光栅构成的耦入结构，设置在所述波导片的入光侧；
    由如权利要求1-7任一项所述的二维光栅构成的耦出结构，设置在所述波导片的出光侧。
  10. 一种近眼显示设备，其特征在于，包括：如权利要求9所述的光波导。
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CN115079323A (zh) * 2022-08-24 2022-09-20 北京亮亮视野科技有限公司 二维耦出光栅、二维衍射光波导和近眼显示设备

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2015093399A (ja) * 2013-11-11 2015-05-18 セイコーエプソン株式会社 転写用の型、転写用の型を用いた回折格子及び光学装置、転写用の型を用いた凹凸形成方法、並びに凹凸形成方法を用いた回折格子の製造方法
CN109459813A (zh) * 2018-12-26 2019-03-12 上海鲲游光电科技有限公司 一种基于二维光栅的平面光波导
US20200166702A1 (en) * 2018-11-26 2020-05-28 Globalfoundries Inc. Waveguide structures
CN111512189A (zh) * 2017-10-02 2020-08-07 瑞士Csem电子显微技术研发中心 谐振波导光栅及其应用
US20220019125A1 (en) * 2018-11-16 2022-01-20 Nippon Telegraph And Telephone Corporation Wavelength Conversion Element and Method for Manufacturing Same
CN114384618A (zh) * 2022-03-23 2022-04-22 深圳珑璟光电科技有限公司 一种二维光栅及其形成方法、光波导及近眼显示设备

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105612584B (zh) * 2013-10-07 2018-12-04 西门子医疗有限公司 相衬x射线成像设备及其相位光栅
JP2017045026A (ja) * 2015-08-27 2017-03-02 パナソニックＩｐマネジメント株式会社 発光素子
CN106597658B (zh) * 2017-03-09 2020-05-22 京东方科技集团股份有限公司 显示面板和显示装置
WO2019004406A1 (ja) * 2017-06-30 2019-01-03 大日本印刷株式会社 回折光学素子及びその製造方法、回折光学素子形成用のアクリル系樹脂組成物、並びに照明装置
CN113495319A (zh) * 2021-07-30 2021-10-12 Oppo广东移动通信有限公司 光学结构和光学装置

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2015093399A (ja) * 2013-11-11 2015-05-18 セイコーエプソン株式会社 転写用の型、転写用の型を用いた回折格子及び光学装置、転写用の型を用いた凹凸形成方法、並びに凹凸形成方法を用いた回折格子の製造方法
CN111512189A (zh) * 2017-10-02 2020-08-07 瑞士Csem电子显微技术研发中心 谐振波导光栅及其应用
US20220019125A1 (en) * 2018-11-16 2022-01-20 Nippon Telegraph And Telephone Corporation Wavelength Conversion Element and Method for Manufacturing Same
US20200166702A1 (en) * 2018-11-26 2020-05-28 Globalfoundries Inc. Waveguide structures
CN109459813A (zh) * 2018-12-26 2019-03-12 上海鲲游光电科技有限公司 一种基于二维光栅的平面光波导
CN114384618A (zh) * 2022-03-23 2022-04-22 深圳珑璟光电科技有限公司 一种二维光栅及其形成方法、光波导及近眼显示设备

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