WO2022170912A1 - 光栅、光学器件及增强现实显示装置 - Google Patents

光栅、光学器件及增强现实显示装置 Download PDF

Info

Publication number
WO2022170912A1
WO2022170912A1 PCT/CN2022/071848 CN2022071848W WO2022170912A1 WO 2022170912 A1 WO2022170912 A1 WO 2022170912A1 CN 2022071848 W CN2022071848 W CN 2022071848W WO 2022170912 A1 WO2022170912 A1 WO 2022170912A1
Authority
WO
WIPO (PCT)
Prior art keywords
grating
layer
trapezoid
refractive index
grating layer
Prior art date
Application number
PCT/CN2022/071848
Other languages
English (en)
French (fr)
Inventor
郑光
Original Assignee
Oppo广东移动通信有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Oppo广东移动通信有限公司 filed Critical Oppo广东移动通信有限公司
Priority to EP22752074.9A priority Critical patent/EP4279962A4/en
Publication of WO2022170912A1 publication Critical patent/WO2022170912A1/zh
Priority to US18/362,567 priority patent/US20240019616A1/en

Links

Images

Classifications

    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B5/00—Optical elements other than lenses
    • G02B5/18—Diffraction gratings
    • G02B5/1866—Transmission gratings characterised by their structure, e.g. step profile, contours of substrate or grooves, pitch variations, materials
    • 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
    • G02B27/017—Head mounted
    • G02B27/0172—Head mounted characterised by optical features
    • 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
    • G02B27/42—Diffraction optics, i.e. systems including a diffractive element being designed for providing a diffractive effect
    • G02B27/4205—Diffraction optics, i.e. systems including a diffractive element being designed for providing a diffractive effect having a diffractive optical element [DOE] contributing to image formation, e.g. whereby modulation transfer function MTF or optical aberrations are relevant
    • 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
    • G02B27/017—Head mounted
    • G02B2027/0178—Eyeglass type

Definitions

  • the present application relates to the field of optical technology, and in particular, to a grating, an optical device and an augmented reality display device.
  • Augmented Reality (AR) display devices such as AR glasses
  • AR glasses can not only see the external real world but also need to see virtual images.
  • Real scenes and virtual information are integrated into one, mutually reinforcing and "enhancing" each other.
  • the external ambient light will be dispersed into rainbow patterns by the out-coupling grating in the AR glasses, which will be injected into the human eye, so that the user can see the rainbow patterns.
  • This phenomenon is called the rainbow effect.
  • the light one will affect the user's experience, and the heavy one will hurt the user's eyes.
  • a first aspect of the present application provides a grating, the grating at least comprising:
  • the first grating layer includes first grating parts and second grating parts that are periodically alternately arranged, wherein the refractive index of the first grating part is greater than the refractive index of the second grating part,
  • the shape of the cross section of the first grating portion is a first trapezoid;
  • a second grating layer is disposed on one side of the first grating layer, the second grating layer includes a third grating portion and a fourth grating portion that are alternately arranged periodically, the third grating portion
  • the refractive index of the grating portion is greater than the refractive index of the fourth grating portion, and at least part of the third grating portion is aligned with the first grating portion, and the cross-sectional shape of the third grating portion is a second trapezoid, The long side of the second trapezoid is disposed away from the first grating portion.
  • a second aspect of the present application provides a grating, the grating at least comprising:
  • a first grating layer for diffracting light to obtain a first diffracted light
  • a second grating layer the second grating is disposed on one side of the first grating layer, and is used for diffracting the light to obtain a second diffracted light, wherein the second diffracted light and the first diffracted light are
  • the range of the phase difference P of a diffracted light is: (2N+1) ⁇ - ⁇ /2 ⁇ P ⁇ (2N+1) ⁇ + ⁇ /2, where N ⁇ 0, and N is an integer.
  • a third aspect of the present application provides an optical device, the optical device includes a polarizer and the grating according to the first aspect and the second aspect, the grating is disposed on one side of the polarizer, and the first grating layer Compared with the second grating layer being disposed away from the polarizer, the polarization state of the polarizer is the TM polarization state.
  • a fourth aspect of the present application provides an augmented reality display device, the augmented reality display device includes the grating according to the first aspect and the second aspect, or the augmented reality display device includes the optical device according to the third aspect device, wherein the grating is a coupling-out grating in the augmented reality display device.
  • FIG. 1 is a schematic three-dimensional structural diagram of a first grating layer in a grating provided by an embodiment of the present application.
  • FIG. 2 is a schematic perspective view of a second grating layer in the grating provided in FIG. 1 .
  • FIG. 3 is a side view of the grating of FIG. 1 .
  • FIG. 4 is a schematic diagram of the action of the grating shown in FIG. 1 on light.
  • FIG. 5 is a schematic diagram illustrating the variation of the normalized amplitudes of the first diffracted light rays and the second diffracted light rays with time of the grating in FIG. 1 .
  • FIG. 6 is a schematic structural diagram of a grating provided by another embodiment of the present application.
  • FIG. 7 is a schematic structural diagram of a grating provided by another embodiment of the present application.
  • FIG. 8 is a schematic view of the dimensions of components in the grating of FIG. 3 .
  • FIG. 9 is a schematic diagram showing the relationship between components in the grating of FIG. 3 .
  • FIG. 10 is a schematic structural diagram of a grating provided by another embodiment of the present application.
  • FIG. 11 is a schematic structural diagram of a grating provided by another embodiment of the present application.
  • FIG. 12 is a schematic structural diagram of a grating provided by another embodiment of the present application.
  • FIG. 13 is a schematic structural diagram of a grating provided by another embodiment of the present application.
  • FIG. 14 is a schematic structural diagram of a grating provided by another embodiment of the present application.
  • FIG. 15 is a schematic structural diagram of a grating provided by another embodiment of the present application.
  • FIG. 16 is a schematic structural diagram of a grating provided by an embodiment of the present application.
  • FIG. 17 is a comparison diagram of the -1-order transmission efficiency of the grating provided by an embodiment of the present application and the single-layer grating in the related art.
  • FIG. 18 is a schematic structural diagram of an optical device provided by an embodiment of the present application.
  • 19 is a graph comparing the -1 order transmission efficiency of a polarizer with TM polarization and a polarizer with TE polarization.
  • FIG. 20 is a schematic structural diagram of an augmented reality display device according to an embodiment of the present application.
  • FIG. 21 is a schematic structural diagram of an augmented reality display device according to an embodiment of the present application.
  • embodiments of the present application provide a grating, where the grating at least includes:
  • the first grating layer includes first grating parts and second grating parts that are periodically alternately arranged, wherein the refractive index of the first grating part is greater than the refractive index of the second grating part,
  • the shape of the cross section of the first grating portion is a first trapezoid;
  • a second grating layer is disposed on one side of the first grating layer, the second grating layer includes a third grating portion and a fourth grating portion that are alternately arranged periodically, the third grating portion
  • the refractive index of the grating portion is greater than the refractive index of the fourth grating portion, and at least part of the third grating portion is aligned with the first grating portion, and the cross-sectional shape of the third grating portion is a second trapezoid, The long side of the second trapezoid is disposed away from the first grating portion.
  • first grating layer and the second grating layer are adhered and fixed together.
  • the range of the refractive index of the first grating part is 1.4-3.0, the range of the refractive index of the second grating part is 1.0-2.0; the range of the refractive index of the third grating part is 1.4-3.0, so The range of the refractive index of the fourth grating portion is 1.0-2.0.
  • the second grating portion and the fourth grating portion include at least one of the following situations:
  • the second grating part is air
  • the fourth grating part is air.
  • the grating also includes:
  • a carrier substrate, the first grating layer and the second grating layer are fixed on the carrier substrate and disposed opposite to each other.
  • first trapezoid and the second trapezoid are both isosceles trapezoids, and the first trapezoid and the second trapezoid include at least one of the following situations:
  • the included angle between the long side of the first trapezoid and the waist of the first trapezoid is greater than 80°;
  • the included angle between the long side of the second trapezoid and the waist of the second trapezoid is greater than 80°.
  • the orthographic projection of the end point of the long side of the first trapezoid on the plane where the long side of the second trapezoid is located completely coincides with the end point of the long side of the second trapezoid adjacent to the first trapezoid.
  • the orthographic projection of the long side of the first trapezoid on the plane where the long side of the second trapezoid is located is at least partially coincident with the long side of the second trapezoid; or, the long side of the first trapezoid is on the
  • the orthographic projection on the plane where the long side of the second trapezoid is located is spaced apart from the long side of the second trapezoid.
  • the height range of the first grating layer is 10nm-1um
  • the height range of the second grating layer is 10nm-1um
  • the period of the first grating layer is the same as the period of the second grating layer, and the period of the first grating layer is 300nm-600nm, and the period of the second grating layer is 300nm-600nm.
  • the grating includes multiple layers of first grating layers and second grating layers which are periodically alternately arranged.
  • embodiments of the present application provide a grating, where the grating at least includes:
  • a first grating layer for diffracting light to obtain a first diffracted light
  • a second grating layer the second grating is disposed on one side of the first grating layer, and is used for diffracting the light to obtain a second diffracted light, wherein the second diffracted light and the first diffracted light are
  • the range of the phase difference P of a diffracted light is: (2N+1) ⁇ - ⁇ /2 ⁇ P ⁇ (2N+1) ⁇ + ⁇ /2, where N ⁇ 0, and N is an integer.
  • the first grating layer includes first grating portions and second grating portions that are alternately arranged periodically, wherein the refractive index of the first grating portion is greater than the refractive index of the second grating portion, and the first grating portion has a higher refractive index than the second grating portion.
  • the shape of the cross section of a grating part is a first trapezoid
  • the second grating layer includes a third grating portion and a fourth grating portion that are alternately arranged periodically, the refractive index of the third grating portion is greater than the refractive index of the fourth grating portion, and at least a refractive index of the third grating portion is greater than that of the fourth grating portion.
  • the third grating portion is partially aligned with the first grating portion, and the cross-sectional shape of the third grating portion is a second trapezoid, and the long side of the second trapezoid is disposed away from the first grating portion.
  • the range of the refractive index of the first grating part is 1.4-3.0, the range of the refractive index of the second grating part is 1.0-2.0; the range of the refractive index of the third grating part is 1.4-3.0, so The range of the refractive index of the fourth grating portion is 1.0-2.0.
  • the height range of the first grating layer is 10nm-1um
  • the height range of the second grating layer is 10nm-1um
  • the period of the first grating layer is the same as the period of the second grating layer, and the period of the first grating layer is 300nm-600nm, and the period of the second grating layer is 300nm-600nm.
  • embodiments of the present application provide an optical device, the optical device includes a polarizer and the grating according to any one of the first aspect or the second aspect, the grating is disposed on one of the polarizers side, and the first grating layer is disposed away from the polarizer compared to the second grating layer, and the polarization state of the polarizer is the TM polarization state.
  • the size of the polarizer is greater than or equal to the size of the grating, and the orthographic projection of the grating on the polarizer falls into the polarizer.
  • embodiments of the present application provide an augmented reality display device, where the augmented reality display device includes the grating according to any one of the first aspect or the second aspect, or the augmented reality display device includes The optical device according to any one of the third aspects, wherein the grating is an out-coupling grating in the augmented reality display device.
  • the augmented reality display device further includes:
  • a wearing frame the wearing frame has two viewing window areas arranged at intervals, and at least one viewing window area of the two viewing window areas is provided with the coupling-out grating.
  • first and second appearing in this application are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implying the number of indicated technical features. Thus, features defined as “first”, “second” may expressly or implicitly include one or more of said features. In the description of this application, the meaning of “plurality” refers to two or more, unless otherwise expressly and specifically defined.
  • FIG. 1 is a schematic three-dimensional structural diagram of a first grating layer in a grating provided by an embodiment of the present application
  • FIG. 2 is a three-dimensional schematic diagram of a second grating layer in the grating provided in FIG. 1
  • FIG. 3 Fig. 1 is a side view of the grating
  • Fig. 4 is a schematic diagram of the action of the grating shown in Fig. 1 on light.
  • the grating 110 includes at least a first grating layer 111 and a second grating layer 113 .
  • the first grating layer 111 is used for diffracting light to obtain the first diffracted light.
  • the second grating 110 is disposed on one side of the first grating layer 111 for diffracting the light to obtain a second diffracted light, wherein the second diffracted light and the first diffracted light
  • the range of the phase difference P is: (2N+1) ⁇ - ⁇ /2 ⁇ P ⁇ (2N+1) ⁇ + ⁇ /2, where N ⁇ 0, and N is an integer.
  • the first grating layer 111 may be spaced from the second grating layer 113 , and the first grating layer 111 may also be stacked and attached to the second grating layer 113 .
  • the first grating layer 111 and the second grating layer 113 are stacked and arranged in a laminated manner, and the grating 110 includes the first grating layer 111 and the second grating layer 113 as example to illustrate.
  • the grating 110 may further include other grating layers in addition to the first grating layer 111 and the second grating layer 113 .
  • light rays incident on the grating 110 are represented by rays 1
  • the first diffracted rays are represented by rays 2
  • the second diffracted rays are represented by rays 3.
  • FIG. 5 is a schematic diagram illustrating the variation of the normalized amplitudes of the first diffracted light rays and the second diffracted light rays of the grating in FIG. 1 with time.
  • the simulation is performed by taking the phase difference between the second diffracted ray and the first diffracted ray as (2N+1) ⁇ as an example.
  • the phase difference between the second diffracted ray and the first diffracted ray is (2N+1) ⁇ , that is, the phase difference between the second diffracted ray and the first diffracted ray is an odd multiple of ⁇ .
  • the abscissa is time, the unit is seconds; the ordinate is the normalized amplitude, no unit.
  • the solid line shows the first diffracted light
  • the dotted line shows the second diffracted light.
  • the amplitudes of the first diffracted light and the second diffracted light are equal in opposite directions, and the phase difference is (2N +1) ⁇ . Therefore, when the first diffracted light and the second diffracted light are superimposed, the superimposed result is zero. That is, the light entering the grating 110 cannot travel out of the grating 110 through the action of the first grating layer 111 and the second grating layer 113 . Therefore, the rainbow pattern phenomenon can be eliminated.
  • the grating 110 is applied in the augmented reality display device 1 , the damage of the rainbow pattern to the eyes of the user wearing the augmented reality display device 1 can be avoided.
  • phase difference between the second diffracted ray and the first diffracted ray is (2N+1) ⁇ , that is, when the phase difference between the second diffracted ray and the first diffracted ray is an odd multiple of ⁇
  • the amplitudes of the first diffracted light rays and the second diffracted light rays are equal and the directions are opposite, the result of the superposition of the first diffracted light rays and the second diffracted light rays is zero.
  • the grating 110 eliminates the rainbow pattern. best effect.
  • the range of the phase difference P between the second diffracted ray and the first diffracted ray is: (2N+1) ⁇ - ⁇ /2 ⁇ P ⁇ (2N+1) ⁇ + ⁇ /2, and P ⁇
  • the first diffracted light and the second diffracted light can also be superimposed to cancel out part, but the part of the first diffracted light and the part of the second diffracted light will exit the grating 110, And then rainbow pattern.
  • the first diffracted light and the second diffracted light can also be superimposed to cancel out a part, the energy of the rainbow pattern emitted from the grating 110 is weakened, that is, the rainbow pattern phenomenon is suppressed.
  • the grating 110 designed the first grating layer 111 and the second grating layer 113 so that the range of the phase difference P between the second diffracted light and the first diffracted light is: (2N +1) ⁇ - ⁇ /2 ⁇ P ⁇ (2N+1) ⁇ + ⁇ /2, where N ⁇ 0, and N is an integer, so that light passing through the grating 110 and passing through the grating can be attenuated or even completely eliminated The phenomenon of rainbow pattern produced when 110 exits.
  • the specific structure of the grating 110 will be described in detail below with reference to the accompanying drawings.
  • the first grating layer 111 includes first grating portions 1111 and second grating portions 1112 which are periodically alternately arranged.
  • the refractive index of the first grating portion 1111 is greater than the refractive index of the second grating portion 1112 , and the cross-sectional shape of the first grating portion 1111 is a first trapezoid.
  • the second grating layer 113 includes third grating portions 1131 and fourth grating portions 1132 which are periodically alternately arranged.
  • the refractive index of the third grating portion 1131 is greater than the refractive index of the fourth grating portion 1132, and at least part of the third grating portion 1131 is aligned with the first grating portion 1111, and the third grating portion 1131
  • the shape of the cross section is a second trapezoid, and the long side of the second trapezoid is disposed away from the first grating portion 1111 .
  • the extending direction of the first grating portion 1111 , the extending direction of the second grating portion 1112 , the extending direction of the third grating portion 1131 , and the extending direction of the fourth grating portion 1132 are the same .
  • the extending direction is the Y direction
  • the stacking direction of the first grating layer 111 and the second grating layer 113 is the Z direction
  • the first grating portion 1111 in the first grating layer 111 is the Z direction.
  • the direction in which the second grating portions 1112 are alternately arranged is the X direction
  • the direction in which the third grating portions 1131 and the fourth grating portions 1132 in the second grating layer 113 are alternately arranged is the X direction as an example for illustration.
  • the first grating layer 111 and the second grating layer 113 form a double-layer grating structure, and the first grating layer 111 and the second grating layer 113 have the same period ⁇ .
  • the first grating 110 includes a first grating portion 1111 and the first grating layer 111 includes a first grating portion 1111 and a second grating portion 1112 which are periodically alternately arranged.
  • the refractive index of the first grating portion 1111 is greater than the refractive index of the second grating portion 1112 .
  • the refractive index of the first grating part 1111 is marked as n12
  • the refractive index of the second grating part 1112 is marked as n11
  • the refractive index of the third grating part 1131 is marked as n22
  • the fourth The refractive index of the grating portion 1132 is marked as n21
  • the refractive index of the medium on the side of the first grating layer 111 away from the second grating layer 113 is marked as n1
  • the second grating layer 113 is away from the first grating layer.
  • the refractive index of the medium on one side of 111 is denoted as n2.
  • the first grating layer 111 is composed of two kinds of grating parts with refractive indices n12 and n11 distributed alternately; the second grating layer 113 is composed of two kinds of grating parts with refractive indices n22 and n21 distributed alternately.
  • At least a part of the third grating portion 1131 is disposed in alignment with the first grating portion 1111 .
  • the third grating portion 1131 is disposed facing the first grating portion 1111 as an example for illustration. .
  • the above-mentioned arrangement of the first grating layer 111 and the second grating layer 113 in the grating 110 of the present application is a structure of double-layer grating dislocation distribution, and the above design can make the gap between the first grating layer 111 and the second grating layer 113 produce a phase difference.
  • the range of the phase difference P between the second diffracted light and the first diffracted light can be: (2N+1) ⁇ - ⁇ /2 ⁇ P ⁇ (2N+1) ⁇ + ⁇ /2, so as to achieve the effect of complete interference cancellation or partial coherence cancellation of the first diffracted light and the second diffracted light, thereby reducing or even eliminating The technical effect of the rainbow pattern effect.
  • the period of the first grating layer 111 can be designed to be the same as the period of the second grating layer 113 , and the period ⁇ of the first grating layer 111 is 300 nm-600 nm.
  • the period ⁇ of the second grating layer 113 is 300 nm-600 nm.
  • the height h1 of the first grating layer 111 can be designed to range from 10 nm to 1 um, and the height h2 of the second grating layer 113 can range from 10 nm to 1 um.
  • h1 and h2 may be equal or unequal.
  • the refractive index of the first grating portion 1111 can be designed to be in the range of 1.4-3.0
  • the refractive index of the second grating portion 1112 can be designed to be in the range of 1.0-2.0
  • the refractive index of the portion 1131 is in the range of 1.4-3.0
  • the refractive index of the fourth grating portion 1132 is in the range of 1.0-2.0.
  • the first grating portion 1111 may be a high refractive index material such as hafnium oxide, titanium oxide, tantalum oxide, etc., and the refractive index distribution thereof may be between 1.7-3.0.
  • the second grating portion 1112 may be a low refractive index material such as air, silicon oxide, optical resin, etc., and the refractive index distribution thereof may be between 1.0 and 2.0.
  • the third refraction part may be a high refractive index material such as hafnium oxide, titanium oxide, and tantalum oxide, and the refractive index distribution thereof may be between 1.7 and 3.0.
  • the fourth grating portion 1132 may be a low refractive index material such as air, silicon oxide, optical resin, etc., and the refractive index distribution thereof may be between 1.0 and 2.0.
  • the second grating portion 1112 and the fourth grating portion 1132 are both air as an example for illustration. It can be understood that, in other embodiments, the grating 110 may also be in the following situation: the second grating portion 1112 is air, and the fourth grating portion 1132 is not air; or, in other embodiments , the second grating portion 1112 is not air, and the fourth grating portion 1132 is air. In other words, the second grating portion 1112 and the fourth grating portion 1132 include at least one of the following conditions: the second grating portion 1112 is air; the fourth grating portion 1132 is air.
  • FIG. 6 is a schematic structural diagram of a grating provided by another embodiment of the present application.
  • the grating 110 includes a carrier substrate 115 in addition to the first grating layer 111 and the second grating layer 113 .
  • the carrier substrate 115 is transparent for light to pass through.
  • the first grating layer 111 and the second grating layer 113 please refer to the above description, and details are not repeated here.
  • the first grating layer 111 and the second grating layer 113 are fixed to the carrier substrate 115 and disposed opposite to each other.
  • the case where the first grating layer 111 and the second grating layer 113 are fixed on the carrier substrate 115 can be applied to the case that the second grating portion 1112 is air or not air, and can be applied to the The fourth grating portion 1132 is air or not air.
  • the second grating portion 1112 is not air and the fourth grating portion 1132 is not air, that is, the second light portion is made of a dielectric base material and the fourth grating portion 1132 is made of a dielectric base material
  • the grating 110 has a thinner thickness.
  • the first grating layer 111 and the second grating layer 113 are fixed on the carrier substrate 115 and face each other During the setting, the grating 110 can be formed into a relatively stable whole, which is convenient for the application of the grating 110 .
  • FIG. 7 is a schematic structural diagram of a grating provided by another embodiment of the present application.
  • the second grating portion 1112 is not air and the fourth grating portion 1132 is not air
  • the second optical deletion portion 1132 is made of a dielectric substrate and the fourth grating portion 1132 is not air.
  • the grating portion 1132 is formed of a dielectric substrate, the first grating layer 111 and the second grating layer 113 are attached and fixed together, so that the grating 110 has a relatively thin thickness.
  • FIG. 8 is a schematic view of the dimensions of the components in the grating in FIG. 3 .
  • the first trapezoid and the second trapezoid are both isosceles trapezoids, and the first trapezoid and the second trapezoid include at least one of the following: the long side of the first trapezoid The included angle ⁇ 1 with the waist of the first trapezoid is greater than 80°; the included angle ⁇ 2 between the long side of the second trapezoid and the waist of the second trapezoid is greater than 80°.
  • the first trapezoid and the second trapezoid are both isosceles trapezoids, and the above-mentioned structural design of the first trapezoid and the second trapezoid can make the first diffracted light and the second diffracted light coherent and destructive. The effect is good.
  • the above-mentioned structural design of the first trapezoid and the second trapezoid can make the first grating layer 111 and the second grating layer 113 easier to manufacture.
  • the first trapezoid may not be an isosceles trapezoid
  • the second trapezoid may not be an isosceles trapezoid, as long as the first grating layer 111 and the second trapezoid can be satisfied.
  • the second grating layer 113 can make the first diffracted light and the second diffracted light at least partially coherent and destructive.
  • FIG. 9 is a schematic diagram of the relationship between components in the grating in FIG. 3 .
  • the end point of the long side of the first trapezoid is named as the end point D1
  • the end point of the long side of the second trapezoid adjacent to the first trapezoid is named the end point D2.
  • the orthographic projection of the end point of the long side of the first trapezoid on the plane where the long side of the second trapezoid is located is completely coincident with the end point of the long side of the second trapezoid adjacent to the first trapezoid, in other words, The orthographic projection of the end point D1 on the plane where the long side of the second trapezoid is located completely coincides with the end point D2.
  • the connecting line L1 between the end point D1 and the end point D2 is perpendicular to the long side of the first trapezoid and is perpendicular to the long side of the second trapezoid.
  • the above-mentioned design of the grating 110 in this embodiment can enable the first diffracted light rays and the second diffracted light rays to have a better coherent cancellation effect, thereby reducing or even avoiding the effect of generating rainbow patterns.
  • FIG. 10 is a schematic structural diagram of a grating provided by another embodiment of the present application.
  • the orthographic projection of the long side of the first trapezoid on the plane where the long side of the second trapezoid is located is at least partially coincident with the long side of the second trapezoid.
  • FIG. 11 is a schematic structural diagram of a grating provided by another embodiment of the present application.
  • the orthographic projection of the long side of the first trapezoid on the plane where the long side of the second trapezoid is located is spaced from the long side of the second trapezoid.
  • FIG. 12 is a schematic structural diagram of a grating provided by another embodiment of the present application.
  • the first grating layer 111 includes first grating portions 1111 and second grating portions 1112 which are periodically alternately arranged.
  • the refractive index of the first grating portion 1111 is greater than the refractive index of the second grating portion 1112, and the shape of the cross-section of the first grating portion 1111 is a first rectangle.
  • the second grating layer 113 includes third grating portions 1131 and fourth grating portions 1132 which are periodically alternately arranged.
  • the refractive index of the third grating portion 1131 is greater than the refractive index of the fourth grating portion 1132, and at least part of the third grating portion 1131 is aligned with the first grating portion 1111, and the third grating portion 1131
  • the shape of the cross section is a second rectangle.
  • the shape of the cross section of the first grating part 1111 is rectangular and the shape of the cross section of the third grating part 1131 is rectangular.
  • the refractive index of the first grating portion 1111 the refractive index of the second grating portion 1112 , the refractive index of the third grating portion 1131 , and the refractive index of the fourth grating portion 1132 .
  • the refractive index of the first grating portion 1111 the refractive index of the second grating portion 1112
  • the material of the first grating portion 1111, the material of the second grating portion 1112, the material of the third grating portion 1131, and the material of the fourth grating portion 1132 It is not repeated here.
  • the height of the first grating layer 111 and the height of the second grating layer 113 please refer to the above description, and details are not repeated here.
  • the light rays incident on the grating 110 are represented by light rays 1
  • the first diffracted light rays are represented by light rays 2
  • the second diffracted light rays are represented by light rays 3.
  • the second grating portion 1112 is not air and the fourth grating portion 1132 is not air, that is, the second light portion is made of a dielectric substrate and the fourth grating portion 1132 is made of
  • the first grating layer 111 and the second grating layer 113 are attached and fixed together, so that the grating 110 has a relatively thin thickness.
  • the first grating layer 111 and the second grating layer 113 are fixed on the carrier substrate 115, and when they are arranged opposite to each other, the grating 110 can be formed into a relatively stable whole, which is convenient for the application of the grating 110.
  • FIG. 13 is a schematic structural diagram of a grating provided by another embodiment of the present application.
  • the second grating portion 1112 and the fourth grating portion 1132 are air.
  • the grating 110 may also be in the following situation: the second grating portion 1112 is air, and the fourth grating portion 1132 is not air; or, in other embodiments, The second grating portion 1112 is not air, and the fourth grating portion 1132 is air.
  • the second grating portion 1112 and the fourth grating portion 1132 include at least one of the following conditions: the second grating portion 1112 is air; the fourth grating portion 1132 is air.
  • FIG. 14 is a schematic structural diagram of a grating provided by another embodiment of the present application.
  • the grating 110 includes a carrier substrate 115 in addition to the first grating layer 111 and the second grating layer 113 .
  • the carrier substrate 115 is transparent for light to pass through.
  • the first grating layer 111 and the second grating layer 113 please refer to the above description, and details are not repeated here.
  • the first grating layer 111 and the second grating layer 113 are fixed to the carrier substrate 115 and disposed opposite to each other.
  • the case where the first grating layer 111 and the second grating layer 113 are fixed on the carrier substrate 115 can be applied to the case that the second grating portion 1112 is air or not air, and can be applied to the The fourth grating portion 1132 is air or not air.
  • the second grating portion 1112 is not air and the fourth grating portion 1132 is not air, that is, the second light portion is made of a dielectric base material and the fourth grating portion 1132 is made of a dielectric base material
  • the grating 110 has a thinner thickness.
  • the first grating layer 111 and the second grating layer 113 are fixed on the carrier substrate 115 and face each other During the setting, the grating 110 can be formed into a relatively stable whole, which is convenient for the application of the grating 110 .
  • the grating 110 further including the carrier substrate 115 is combined into the embodiment shown in FIG. 13 as an example for illustration.
  • FIG. 15 is a schematic structural diagram of a grating provided by another embodiment of the present application.
  • the first grating layer 111 includes first grating portions 1111 and second grating portions 1112 which are periodically alternately arranged.
  • the refractive index of the first grating portion 1111 is greater than the refractive index of the second grating portion 1112, and the shape of the cross-section of the first grating portion 1111 is a first rectangle.
  • the second grating layer 113 includes third grating portions 1131 and fourth grating portions 1132 which are periodically alternately arranged.
  • the refractive index of the third grating portion 1131 is greater than the refractive index of the fourth grating portion 1132 , and at least part of the third grating portion 1131 is aligned with the first grating portion 1111 .
  • the first grating layer 111 and the second grating layer 113 are connected as a whole through the connecting layer 117 , and the first grating layer 111 and the second grating layer 113 are disposed on the Connect the opposite sides of the layer 117 .
  • the first grating layer 111 , the second grating layer 113 and the connecting layer 117 have an integrated structure.
  • the structure of the grating 110 in this embodiment not only weakens or even eliminates the rainbow pattern, but also reduces the technological difficulty in the preparation of the grating 110 .
  • the first grating portion 1111 , the second grating portion 1112 and the connection layer 117 have the same refractive index.
  • the second grating portion 1112 and the fourth grating portion 1132 are gas.
  • the first grating layer 111 can be regarded as including a plurality of first grating parts 1111 arranged at intervals
  • the second grating layer 113 can be regarded as including a plurality of third grating parts 1131 arranged at intervals.
  • the refractive index of the second grating portion 1112 is the same as the refractive index of the fourth grating portion 1132 .
  • the refractive index of the second grating portion 1112 is different from the refractive index of the fourth grating portion 1132 .
  • the light rays incident on the grating 110 are represented by light rays 1
  • the first diffracted light rays are represented by light rays 2
  • the second diffracted light rays are represented by light rays 3.
  • the grating 110 in the various embodiments described above may be a binary grating 110 .
  • the cross-section of the first grating portion 1111 is a first trapezoid and the cross-sectional shape of the third grating portion 1131 is a second trapezoidal grating 110 .
  • the grating 110 in which the cross-section of the first grating portion 1111 is a first rectangle and the cross-sectional shape of the third grating portion 1131 is a second rectangle is easier to manufacture in actual production and has better processability.
  • the grating 110 includes multiple layers of the first grating layer 111 and the second grating layer 113 which are periodically and alternately arranged.
  • the first grating layer 111 and the second grating layer 113 serve as repeatable grating composite layers 110a
  • the grating 110 includes a plurality of (three are shown in the figure) grating composite layers 110a.
  • the plurality of grating composite layers 110a are stacked along the direction in which the first grating layer 111 and the second grating layer 113 are stacked.
  • the plurality of grating composite layers 110a are stacked along the Z-axis.
  • the specific settings of the first grating layer 111 and the second grating layer 113 reference may be made to the description of any of the foregoing embodiments, which will not be repeated here.
  • the specific structure of the first grating layer 111 and the specific structure of the second grating layer 113 in the schematic diagram of this embodiment are only for illustration, and should not be construed as a limitation on the grating 110 provided in the embodiment of the present application.
  • the grating 110 includes a plurality of the grating composite layers 110a arranged in layers, which can further Reduces the rainbow pattern.
  • FIG. 17 is a comparison diagram of the -1-order transmission efficiency of the grating provided by an embodiment of the present application and the single-layer grating in the related art.
  • the grating 110 of the present application is a double-layer grating including a first grating layer 111 and a second grating layer 113 .
  • the horizontal axis is the wavelength, the unit is um; the vertical axis is the transmission efficiency, no unit.
  • the dotted line is the curve of the grating 110 of the present application, and the solid line is the curve of the single-layer grating 110 .
  • the transmission efficiency of the -1 level of the grating 110 of the present application is lower than the transmission efficiency of the -1 level of the single-layer grating 110 in the related art. Therefore, compared with the single-layer grating 110 in the related art, the grating 110 provided by the embodiment of the present application can significantly reduce the transmission efficiency of -1 level. It can be seen that the grating 110 provided by the embodiment of the present application can reduce or even avoid the generation of rainbow patterns. effect is more obvious.
  • FIG. 18 is a schematic structural diagram of an optical device provided by an embodiment of the application
  • FIG. 19 is a -1-level transmission efficiency of a polarizer with TM polarization state and a polarizer with TE polarization state comparison chart.
  • the optical device 10 includes a polarizer 130 and the grating 110 described in any one of the foregoing embodiments, the grating 110 is disposed on one side of the polarizer 130 , and the first grating layer 111 is relatively The second grating layer 113 is disposed away from the polarizer 130 , and the polarization state of the polarizer 130 is the TM polarization state.
  • the polarizer 130 may be spaced from the grating 110 , or may be disposed in contact with the grating 110 .
  • the horizontal axis is the wavelength, and the unit is um; the vertical axis is the transmission efficiency, and there is no unit.
  • the solid line in the figure is the curve of the -1 order transmission efficiency of the polarizer 130 with the TM polarization state; the dotted line in the figure is the curve of the -1 order transmission efficiency of the polarizer 130 with the TE polarization state, as can be seen from the comparison diagram.
  • the -1 order transmission efficiency of the polarizer 130 with the TM polarization state is smaller than the -1 order transmission efficiency of the polarizer 130 with the TE polarization state.
  • the polarizer 130 with the TM polarization state is disposed on one side of the grating 110, and the first grating layer 111 is disposed away from the polarizer 130 compared to the second grating layer 113, so that the light The polarizer 130 is acted first, and then the second grating 110 is passed to the first grating 110 . Therefore, the optical device 10 provided by the embodiment of the application has an obvious effect of weakening or even preventing rainbow patterns.
  • the size of the polarizer 130 is greater than or equal to the size of the grating 110 , and the orthographic projection of the grating 110 on the polarizer 130 falls into the polarizer 130 .
  • the above arrangement of the polarizer 130 and the grating 110 in the optical device 10 can make the polarizer 130 large enough to act on the light before entering the grating 110 to further reduce or even avoid the rainbow effect.
  • FIG. 20 is a schematic structural diagram of an augmented reality display device according to an embodiment of the present application.
  • the Augmented Reality (AR) display device 1 includes the grating 110 described in any of the foregoing embodiments.
  • the augmented reality display device 1 includes the optical device 10 described in any of the foregoing embodiments, wherein the grating 110 in the optical device 10 is a coupling-out grating in the augmented reality display device 1 .
  • the augmented reality display device 1 includes the grating 110
  • the augmented reality display device 1 may or may not include the polarizer 130 .
  • the augmented reality display device 1 includes the polarizer 130 and the grating as an example for illustration.
  • the grating 110 is an out-coupling grating in the augmented reality display device 1
  • the grating 110 described in the previous embodiments has no effect on the normal transmission of ambient light, and has no effect on the out-coupling grating included in the augmented reality display device 1 .
  • the performance of the diffractive waveguide, including the grating, is not significantly affected.
  • FIG. 21 is a schematic structural diagram of an augmented reality display device according to an embodiment of the present application.
  • the augmented reality display device 1 can be AR glasses, and can also be applied to a device with a windshield such as a car.
  • the enhanced display device 1 is taken as an example of AR glasses for illustration.
  • the augmented reality display device 1 further includes a wearing frame 30 .
  • the wearing frame 30 has two window areas 310 arranged at intervals, and at least one window area 310 of the two window areas 310 is provided with the coupling-out grating (ie, the grating 110 ) and the polarizer 130 .
  • the outcoupling grating is set in the two window regions 310 as an example for illustration. It should be noted that, in the schematic diagram of this embodiment, the specific shape of the out-coupling grating is not shown. For the shape of the out-coupling grating, please refer to the grating introduced in any of the foregoing embodiments.

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Diffracting Gratings Or Hologram Optical Elements (AREA)

Abstract

一种光栅（110）、光学器件（10）及增强现实显示装置（1）。光栅（110）至少包括第一光栅层（111）及第二光栅层（113）。第一光栅层（111）包括周期性交替排布的第一光栅部（1111）及第二光栅部（1112），其中，第一光栅部（1111）的折射率大于第二光栅部（1112）的折射率，第一光栅部（1111）的横截面的形状为第一梯形。第二光栅层（113）设置于第一光栅层（111）的一侧，第二光栅层（113）包括周期性交替排布的第三光栅部（1131）及第四光栅部（1132），第三光栅部（1131）的折射率大于第四光栅部（1132）的折射率，且第三光栅部（1131）的至少部分对准第一光栅部（1111）设置，第三光栅部（1131）的横截面的形状为第二梯形，第二梯形的长边背离第一光栅部（1111）设置。这种光栅（110）可减小甚至消除彩虹纹效应。

Description

光栅、光学器件及增强现实显示装置 技术领域
本申请涉及光学技术领域，具体涉及一种光栅、光学器件及增强现实显示装置。
背景技术
随着技术的发展，增强现实(Augmented Reality，AR)显示装置，比如AR眼镜，既能看到外部真实的世界也需要看到虚拟的图像。真实场景和虚拟信息融合为一体，相互补强，相互“增强”。然，当用户使用增强现实显示装置时，比如，佩戴所述AR眼镜时，外部环境光线会被AR眼镜中的耦出光栅色散成彩虹纹，射入人眼，使用户看到彩虹条纹，这种现象称为彩虹纹效应。当用户看到彩虹纹时，轻者会影响用户的使用体验，重者会伤害用户的眼睛。
发明内容
本本申请第一方面提供了一种光栅，所述光栅至少包括：
第一光栅层，所述第一光栅层包括周期性交替排布的第一光栅部及第二光栅部，其中，所述第一光栅部的折射率大于所述第二光栅部的折射率，所述第一光栅部的横截面的形状为第一梯形；及
第二光栅层，所述第二光栅层设置于所述第一光栅层的一侧，所述第二光栅层包括周期性交替排布的第三光栅部及第四光栅部，所述第三光栅部的折射率大于所述第四光栅部的折射率，且第三光栅部的至少部分对准所述第一光栅部设置，所述第三光栅部的横截面的形状为第二梯形，所述第二梯形的长边背离所述第一光栅部设置。
本申请第二方面提供了一种光栅，所述光栅至少包括：
第一光栅层，所述第一光栅层用于对光线进行衍射，以得到第一衍射光线；及
第二光栅层，所述第二光栅设置于所述第一光栅层的一侧，用于对所述光线进行衍射，以得到第二衍射光线，其中，所述第二衍射光线及所述第一衍射光的相位差P的范围为：(2N+1)π-π/2≤P≤(2N+1)π+π/2，其中N≥0，且N为整数。
本申请第三方面提供了一种光学器件，光学器件包括偏振片及第一方面及第二方面所述的光栅，所述光栅设置于所述偏振片的一侧，且所述第一光栅层相较于所述第二光栅层背离所述偏振片设置，所述偏振片的偏振态为TM偏振态。
本申请第四方面提供一种增强现实显示装置，所述增强现实显示装置包括如第一方面及第二方面所述的光栅，或者，所述增强现实显示装置包括如第三方面所述的光学器件，其中，所述光栅为所述增强现实显示装置中的耦出光栅。
附图说明
图1为本申请一实施方式提供的光栅中第一光栅层的立体结构示意图。
图2为图1提供的光栅中第二光栅层的立体示意图。
图3为图1中光栅的侧视图。
图4为图1中所示的光栅对光线的作用示意图。
图5为图1中的光栅的第一衍射光线及第二衍射光线归一化振幅随着时间的变化示意图。
图6为本申请另一实施方式提供的光栅的结构示意图。
图7为本申请另一实施方式提供的光栅的结构示意图。
图8为图3中的光栅中部件的尺寸示意图。
图9为图3中的光栅中部件的关系示意图。
图10为本申请另一实施方式提供的光栅的结构示意图。
图11为本申请另一实施方式提供的光栅的结构示意图。
图12为本申请另一实施方式提供的光栅的结构示意图。
图13为本申请另一实施方式提供的光栅的结构示意图。
图14为本申请另一实施方式提供的光栅的结构示意图。
图15为本申请另一实施方式提供的光栅的结构示意图。
图16为本申请一实施方式提供的光栅的结构示意图。
图17为本申请一实施方式提供的光栅和相关技术中的单层光栅的-1级透射效率的对比图。
图18为本申请一实施方式提供的光学器件的结构示意图。
图19为具有TM偏振态的偏振片及具有TE偏振态的偏振片的-1级透射效率的对比图。
图20为本申请一实施方式提供的增强现实显示装置的结构示意图。
图21为本申请一实施方式提供的增强现实显示装置的结构示意图。
具体实施方式
第一方面，本申请实施方式提供一种光栅，所述光栅至少包括：
第一光栅层，所述第一光栅层包括周期性交替排布的第一光栅部及第二光栅部，其中，所述第一光栅部的折射率大于所述第二光栅部的折射率，所述第一光栅部的横截面的形状为第一梯形；及
第二光栅层，所述第二光栅层设置于所述第一光栅层的一侧，所述第二光栅层包括周期性交替排布的第三光栅部及第四光栅部，所述第三光栅部的折射率大于所述第四光栅部的折射率，且第三光栅部的至少部分对准所述第一光栅部设置，所述第三光栅部的横截面的形状为第二梯形，所述第二梯形的长边背离所述第一光栅部设置。
其中，所述第一光栅层与所述第二光栅层贴合固定在一起。
其中，所述第一光栅部的折射率的范围为1.4-3.0，所述第二光栅部的折射率的范围为1.0-2.0；所述第三光栅部的折射率范围为1.4-3.0，所述第四光栅部的折射率的范围为1.0-2.0。
其中，所述第二光栅部及所述第四光栅部包括如下情况中的至少一种：
所述第二光栅部为空气；
所述第四光栅部为空气。
其中，所述光栅还包括：
承载基板，所述第一光栅层及所述第二光栅层固定于所述承载基板，且相背设置。
其中，所述第一梯形及第二梯形均为等腰梯形，且所述第一梯形及所述第二梯形包括如下情况中的至少一种：
所述第一梯形的长边与所述第一梯形的腰之间的夹角大于80°；
所述第二梯形的长边与所述第二梯形的腰之间的夹角大于80°。
其中，所述第一梯形的长边的端点在第二梯形的长边所在的平面上的正投影与所述第二梯形的长边中邻近所述第一梯形的端点完全重合。
其中，第一梯形的长边在所述第二梯形的长边所在的平面上的正投影与所述第二梯形的长边至少部分重合；或者，所述第一梯形的长边在所述第二梯形的长边所在的平面上的正投影与所述第二梯形的长边间隔设置。
其中，所述第一光栅层的高度范围为10nm-1um，所述第二光栅层的高度范围为10nm-1um。
其中，所述第一光栅层的周期与所述第二光栅层的周期相同，且所述第一光栅层的周期为300nm-600nm，所述第二光栅层的周期为300nm-600nm。
其中，所述光栅包括周期性交替排布的多层第一光栅层及第二光栅层。
第二方面，本申请实施方式提供一种光栅，所述光栅至少包括：
第一光栅层，所述第一光栅层用于对光线进行衍射，以得到第一衍射光线；及
第二光栅层，所述第二光栅设置于所述第一光栅层的一侧，用于对所述光线进行衍射，以得到第二衍射光线，其中，所述第二衍射光线及所述第一衍射光的相位差P的范围为：(2N+1)π-π/2≤P≤(2N+1)π+π/2，其中N≥0，且N为整数。
其中，所述第一光栅层包括周期性交替排布的第一光栅部及第二光栅部，其中，所述第一光栅部的折射率大于所述第二光栅部的折射率，所述第一光栅部的横截面的形状为第一梯形；
所述第二光栅层包括周期性交替排布的第三光栅部及第四光栅部，所述第三光栅部的折射率大于所述第四光栅部的折射率，且第三光栅部的至少部分对准所述第一光栅部设置，所述第三光栅部的横截面的形状为第二梯形，所述第二梯形的长边背离所述第一光栅部设置。
其中，所述第一光栅部的折射率的范围为1.4-3.0，所述第二光栅部的折射率的范围为1.0-2.0；所述第三光栅部的折射率范围为1.4-3.0，所述第四光栅部的折射率的范围为1.0-2.0。
其中，所述第一光栅层的高度范围为10nm-1um，所述第二光栅层的高度范围为10nm-1um。
其中，所述第一光栅层的周期与所述第二光栅层的周期相同，且所述第一光栅层的周期为300nm-600nm，所述第二光栅层的周期为300nm-600nm。
第三方面，本申请实施方式提供一种光学器件，所述光学器件包括偏振片及第一方面或第二方面中的任意一项所述的光栅，所述光栅设置于所述偏振片的一侧，且所述第一光栅层相较于所述第二光栅层背离所述偏振片设置，所述偏振片的偏振态为TM偏振态。
其中，所述偏振片的尺寸大于或等于所述光栅的尺寸，且所述光栅在所述偏振片上的正投影落入所述偏振片内。
第四方面，本申请实施方式提供一种增强现实显示装置，所述增强现实显示装置包括如第一方面或第二方面中的任意一项所述的光栅，或者，所述增强现实显示装置包括如第三方面中的任意一项所述的光学器件，其中，所述光栅为所述增强现实显示装置中的耦出光栅。
其中，所述增强现实显示装置还包括：
佩戴框，所述佩戴框具有间隔设置的两个视窗区，所述两个视窗区的至少一个视窗区设置有所述耦出光栅。
下面将结合本申请实施方式中的附图，对本申请实施方式中的技术方案进行清楚、完整的描述，显然，所描述的实施方式仅是本申请一部分实施方式，而不是全部的实施方式。基于本申请中的实施方式，本领域普通技术人员在没有做出创造性劳动前提下所获得的所有其他实施方式，都属于本申请保护的范围。
需要说明的是，在本文中提及“实施例”或“实施方式”意味着，结合实施例或实施方式描述的特定特征、结构或特性可以包含在本申请的至少一个实施例中。在说明书中的各个位置出现该短语并不一定均是指相同的实施例，也不是与其它实施例互斥的独立的或备选的实施例。本领域技术人员显式地和隐式地理解的是，本文所描述的实施例可以与其它实施例相结合。
本申请中出现的术语“第一”、“第二”仅仅用于描述的目的，而不能理解为指示或者暗示相对重要性或者隐含指明所指示的技术特征的数量。由此，限定有“第一”、“第二”的特征可以明示或隐含地包括一个或者更多个所述特征。在本申请的描述中，“多个”的含义是指两个或两个以上，除非另有明确具体的限定。
请一并参阅图1至图4，图1为本申请一实施方式提供的光栅中第一光栅层的立体结构示意图；图2为图1提供的光栅中第二光栅层的立体示意图；图3为图1中光栅的侧视图；图4为图1中所示的光栅对光线的作用示意图。所述光栅110包括至少第一光栅层111及第二光栅层113。所述第一光栅层111用于对光线进行衍射，以得到第一衍射光线。所述第二光栅110设置于所述第一光栅层111的一侧，用于对所述光线进行衍射，以得到第二衍射光线，其中，所述第二衍射光线及所述第一衍射光的相位差P的范围为：(2N+1)π-π/2≤P≤(2N+1)π+π/2，其中N≥0，且N为整数。
所述第一光栅层111可与所述第二光栅层113间隔设置，所述第一光栅层111也可与所述第二光栅层113层叠且贴合设置。在本实施方式的示意图中，以所述第一光栅层111及所述第二光栅层113层叠且贴合设置且以所述光栅110包括第一光栅层111及所述第二光栅层113为例进行示意。在其他实施方式中，所述光栅110除了包括所述第一光栅层111及所述第二光栅层113之外还可包括其他光栅层。
在图4中，以光线①表示入射至光栅110的光线，以光线②表示第一衍射光线，以光线③表示第二衍射光线。
请一并参阅图5，图5为图1中的光栅的第一衍射光线及第二衍射光线归一化振幅随着时间的变化示意图。在图5中，以所述第二衍射光线与所述第一衍射光线的相位差为(2N+1)π为例进行仿真。当所述第二衍射光线与所述第一衍射光线的相位差为(2N+1)π时，即所述第二衍射光线与所述第一衍射光线的相位差为π的奇数倍。在图5中，横坐标为时间，单位为秒；纵坐标为归一化振幅，无单位。在图5中，实线所示的为第一衍射光线，虚线所示的为第二衍射光线，由图5可见，第一衍射光线和第二衍射光线的振幅相等方向相反，相位相差(2N+1)π。因此，当所述第一衍射光线及所述第二衍射光线叠加时，叠加的结果为零。即，进入到所述光栅110中的光线，经过所述第一光栅层111及所述第二光栅层113的作用，无法从所述光栅110中传播出去。因此，可消除彩虹纹现象。当所述光栅110应用于增强现实显示装置1中时，可避免所述彩虹纹对佩戴所述增强现实显示装置1的用户眼睛的损伤。
当所述第二衍射光线与所述第一衍射光线的相位差为(2N+1)π时，即所述第二衍射光线与所述第一衍射光线的相位差为π的奇数倍时，由于所述第一衍射光线和所述第二衍射光线的振幅相等，方向相反，因此第一衍射光线及第二衍射光线叠加后的结果为零，此时，所述光栅110对彩虹纹的消除效果最好。
当所述第二衍射光线与所述第一衍射光线的相位差P的范围为：(2N+1)π-π/2≤P≤(2N+1)π+π/2时，且P≠(2N+1)π时，所述第一衍射光和所述第二衍射光也可叠加进而抵消掉部分，但是第一衍射光线的部分及第二衍射光线的部分会射出所述光栅110，进而彩虹纹。然，由于所述第一衍射光和所述第二衍射光也可叠加进而抵消掉部分，射出所述光栅110的彩虹纹的能量被削弱，即，所述彩虹纹现象被抑制。
由上述分析可见，本实施方式提供的光栅110通过设计第一光栅层111及第二光栅层113，使得所述第二衍射光线及所述第一衍射光的相位差P的范围为：(2N+1)π-π/2≤P≤(2N+1)π+π/2，其中N≥0，且N为整数，从而可削弱甚至完全消除光线穿过所述光栅110并经由所述光栅110出射时产生的彩虹纹现象。下面结合附图对所述光栅110的具体结构进行详细介绍。
请进一步参阅图1至图4，在本实施方式中，所述第一光栅层111包括周期性交替排布的第一光栅部1111及第二光栅部1112。其中，所述第一光栅部1111的折射率大于所述第二光栅部1112的折射率，所述第一光栅部1111的横截面的形状为第一梯形。所述第二光栅层113包括周期性交替排布的第三光栅部1131及第四光栅部1132。所述第三光栅部1131的折射率大于所述第四光栅部1132的折射率，且第三光栅部1131的至少部分对准所述第一光栅部1111设置，所述第三光栅部1131的横截面的形状为第二梯形，所述第二梯形的长边背离所述第一光栅部1111设置。
需要说明的是，所述第一光栅部1111的延伸方向、所述第二光栅部1112的延伸方向及所述第三光栅部1131的延伸方向、及所述第四光栅部1132的延伸方向相同。在本实施方式中，以所述延伸方向为Y方向，所述第一光栅层111及所述第二光栅层113的层叠方向为Z方向，所述第一光栅层111中第一光栅部1111及所述第二光栅部1112交替排布的方向为X方向，所述第二光栅层113中第三光栅部1131及第四光栅部1132交替排布的方向为X方向为例进行示意。
所述第一光栅层111与所述第二光栅层113形成双层光栅结构，所述第一光栅层111与所述第二光栅层113具有相同的周期Λ。所述第一光栅110包括第一光栅部1111及所述第一光栅层111包括周期性交替排布的第一光栅部1111及第二光栅部1112。其中，所述第一光栅部1111的折射率大于所述第二光栅部1112的折射率。为了方便描述，所述第一光栅部1111的折射率标记为n12，所述第二光栅部1112的折射率标记为n11；所述第三光栅部1131的折射率标记为n22，所述第四光栅部1132的折射率标记 为n21；所述第一光栅层111背离所述第二光栅层113的一侧介质的折射率记为n1，所述第二光栅层113背离所述第一光栅层111的一侧的介质的折射率记为n2。换而言之，所述第一光栅层111由折射率为n12和n11的两种光栅部交替分布构成；所述第二光栅层113由折射率为n22和n21的两种光栅部交替分布构成。所述第三光栅部1131的至少部分对准所述第一光栅部1111设置，在本实施方式的示意图中以所述第三光栅部1131正对所述第一光栅部1111设置为例进行示意。本申请的光栅110中的第一光栅层111及第二光栅层113的上述设置方式为双层光栅错位分布的结构，上述设计可使得所述第一光栅层111和第二光栅层113之间产生相位差。通过设计第一光栅层111的结构参数及第二光栅层113的结构参数可使得所述第二衍射光线及所述第一衍射光的相位差P的范围为：(2N+1)π-π/2≤P≤(2N+1)π+π/2，从而达到所述第一衍射光线及所述第二衍射光线完全相干涉相消或者部分相干相消的效果，进而达到减小甚至消除彩虹纹效应的技术效果。
具体地，在一实施方式中，可设计所述第一光栅层111的周期与所述第二光栅层113的周期相同，且所述第一光栅层111的周期Λ为300nm-600nm，所述第二光栅层113的周期Λ为300nm-600nm。
具体地，在一实施方式中，可设计所述第一光栅层111的高度h1的高度范围为10nm-1um，所述第二光栅层113的高度h2的高度范围为10nm-1um。其中，h1与h2可以相等也可以不相等。
具体地，在一实施方式中，可设计所述第一光栅部1111的折射率的范围为1.4-3.0，所述第二光栅部1112的折射率的范围为1.0-2.0；所述第三光栅部1131的折射率范围为1.4-3.0，所述第四光栅部1132的折射率的范围为1.0-2.0。
在一实施方式中，所述第一光栅部1111可以为氧化铪，氧化钛，氧化钽等高折射率材料，其折射率分布可以为1.7-3.0之间。所述第二光栅部1112可以为空气，氧化硅，光学树脂等低折射率材料，其折射率分布可以为1.0-2.0之间。相应地，所述第三折射部可以为氧化铪，氧化钛，氧化钽等高折射率材料，其折射率分布可以为1.7-3.0之间。所述第四光栅部1132可以为空气，氧化硅，光学树脂等低折射率材料，其折射率分布可以为1.0-2.0之间。一般而言，所述第一光栅部1111的折射率n12和所述第二光栅部1112的折射率n11，之间的差别越大规避彩虹纹的效果越明显，相应地，所述第三光栅部1131的折射率n22,述第四光栅部1132的折射率n21之间的差别越大，减弱甚至避免产生彩虹纹的效果越明显。
在本实施方式的示意图中，以所述第二光栅部1112及所述第四光栅部1132均为空气为例进行示意。可以理解地，在其他实施方式中，所述光栅110也可以为如下的情况：所述第二光栅部1112为空气，所述第四光栅部1132不为空气；或者，在另外的实施方式中，所述第二光栅部1112不为空气，所述第四光栅部1132为空气。换而言之，所述第二光栅部1112及所述第四光栅部1132包括如下情况中的至少一种：所述第二光栅部1112为空气；所述第四光栅部1132为空气。
请参阅图6，图6为本申请另一实施方式提供的光栅的结构示意图。在本实施方式中，所述光栅110除了包括第一光栅层111及第二光栅层113之外，还包括承载基板115。可以理解地，所述承载基板115为透明的，以供光线穿过。所述第一光栅层111及所述第二光栅层113请参阅前面描述，在此不再赘述。在本实施方式中，所述第一光栅层111及所述第二光栅层113固定于所述承载基板115，且相背设置。所述第一光栅层111及所述第二光栅层113固定于所述承载基板115上的情况可适用于所述第二光栅部1112为空气或者不为空气的情况，且可适用于所述第四光栅部1132为空气或者不为空气的情况。当所述第二光栅部1112为不为空气且所述第四光栅部1132不空气时，即，所述第二光部由介质基材构成且所述第四光栅部1132由介质基材构成时，所述第一光栅层111与所述第二光栅层113贴合固定在一起，从而使得所述光栅110具有较薄的厚度。当所述第二光栅部1112及所述第四光栅部1132中的至少一个为空气时，所述第一光栅层111及所述第二光栅层113固定于所述承载基板115，且相背设置时，可使得所述光栅110形成较为稳固的整体，方便所述光栅110的应用。
请参阅图7，图7为本申请另一实施方式提供的光栅的结构示意图。在本实施方式中，当所述第二光栅部1112为不为空气且所述第四光栅部1132不空气时，即，所述第二光删部1132由介质基材构成且所述第四光栅部1132由介质基材构成时，所述第一光栅层111与所述第二光栅层113贴合固定在一 起，从而使得所述光栅110具有较薄的厚度。
请参阅图8，图8为图3中的光栅中部件的尺寸示意图。在本实施方式中，所述第一梯形及第二梯形均为等腰梯形，且所述第一梯形及所述第二梯形包括如下情况中的至少一种：所述第一梯形的长边与所述第一梯形的腰之间的夹角α1大于80°；所述第二梯形的长边与所述第二梯形的腰之间的夹角α2大于80°。
所述第一梯形及所述第二梯形均为等腰梯形，且所述第一梯形及第二梯形的上述结构设计可使得所述第一衍射光线及所述第二衍射光线相干相消的效果较好，此外，所述第一梯形及第二梯形的上述结构设计可使得所述第一光栅层111及所述第二光栅层113更容易制备出来。需要说明的是，在其他实施方式中，所述第一梯形也可不为等腰梯形，所述第二梯形也可以不为等腰梯形，只要能够满足所述第一光栅层111及所述第二光栅层113使得所述第一衍射光线及第二衍射光线至少部分相干相消即可。
请参阅图9，图9为图3中的光栅中部件的关系示意图。所述第一梯形的长边的端点在第二梯形的长边所在的平面上的正投影与所述第二梯形的长边中邻近所述第一梯形的端点完全重合。
将所述第一梯形的长边的端点命名为端点D1，将第二梯形的长边中邻近所述第一梯形的端点命名为端点D2。所述第一梯形的长边的端点在第二梯形的长边所在的平面上的正投影与所述第二梯形的长边中邻近所述第一梯形的端点完全重合，换而言之，所述端点D1在所述第二梯形的长边所在的平面上的正投影与所述端点D2完全重合。此时，所述端点D1及所述端点D2的连线L1垂直于所述第一梯形的长边，且垂直于所述第二梯形的长边。在本实施方式中的光栅110的上述设计方式可使得所述第一衍射光线及所述第二衍射光线具有较好的相干相消效果，进而减弱甚至避免产生彩虹纹的效果。
请参阅图10，图10为本申请另一实施方式提供的光栅的结构示意图。在本实施方式中，第一梯形的长边在所述第二梯形的长边所在的平面上的正投影与所述第二梯形的长边至少部分重合。
请参阅图11，图11为本申请另一实施方式提供的光栅的结构示意图。在本实施方式中，所述第一梯形的长边在所述第二梯形的长边所在的平面上的正投影与所述第二梯形的长边间隔设置。
在图10及图11及其描述的光栅110中，虽然第一衍射光线及第二衍射光线的相干相消的效果不如图9及其相关实施方式中的效果，但是，也可减弱彩虹纹。
请参阅图12，图12为本申请另一实施方式提供的光栅的结构示意图。所述第一光栅层111包括周期性交替排布的第一光栅部1111及第二光栅部1112。其中，所述第一光栅部1111的折射率大于所述第二光栅部1112的折射率，所述第一光栅部1111的横截面的形状为第一矩形。所述第二光栅层113包括周期性交替排布的第三光栅部1131及第四光栅部1132。所述第三光栅部1131的折射率大于所述第四光栅部1132的折射率，且第三光栅部1131的至少部分对准所述第一光栅部1111设置，所述第三光栅部1131的横截面的形状为第二矩形。换而言之，与前面实施方式不同的是，在本实施方式中，所述第一光栅部1111的横截面的形状为矩形且所述第三光栅部1131的横截面的形状为矩形。
所述第一光栅部1111的折射率、所述第二光栅部1112的折射率、所述第三光栅部1131的折射率及所述第四光栅部1132的折射率的情况具体请参阅前面描述，在此不再赘述。相应地，所述第一光栅部1111的材质、所述第二光栅部1112的材质、所述第三光栅部1131的材质及所述第四光栅部1132的材质的情况具体请参阅前面描述，在此不再赘述。
所述第一光栅层111的周期、所述第二光栅层113的周期请参阅前面描述，在此不再赘述。
所述第一光栅层111的高度、所述第二光栅层113的高度请参阅前面描述，在此不再赘述。
同样地，在本实施方式的示意图中以光线①表示入射至光栅110的光线，以光线②表示第一衍射光线，以光线③表示第二衍射光线。
在本实施方式中，所述第二光栅部1112为不为空气且所述第四光栅部1132不空气，即，所述第二光部由介质基材构成且所述第四光栅部1132由介质基材构成时，所述第一光栅层111与所述第二光栅层113贴合固定在一起，从而使得所述光栅110具有较薄的厚度。在其他实施方式中，所述第二光栅部1112及所述第四光栅部1132中的至少一个为空气时，所述第一光栅层111及所述第二光栅层113固定于所述承载基板115，且相背设置时，可使得所述光栅110形成较为稳固的整体，方便所述光栅110的应用。
请参阅图13，图13为本申请另一实施方式提供的光栅的结构示意图。在本实施方式中，所述第二光栅部1112及所述第四光栅部1132为空气。可以理解地，在其他实施方式中所述光栅110也可以为如下的情况：所述第二光栅部1112为空气，所述第四光栅部1132不为空气；或者，在另外的实施方式中，所述第二光栅部1112不为空气，所述第四光栅部1132为空气。换而言之，所述第二光栅部1112及所述第四光栅部1132包括如下情况中的至少一种：所述第二光栅部1112为空气；所述第四光栅部1132为空气。
请参阅图14，图14为本申请另一实施方式提供的光栅的结构示意图。在本实施方式中，所述光栅110除了包括第一光栅层111及第二光栅层113之外，还包括承载基板115。可以理解地，所述承载基板115为透明的，以供光线穿过。所述第一光栅层111及所述第二光栅层113请参阅前面描述，在此不再赘述。在本实施方式中，所述第一光栅层111及所述第二光栅层113固定于所述承载基板115，且相背设置。所述第一光栅层111及所述第二光栅层113固定于所述承载基板115上的情况可适用于所述第二光栅部1112为空气或者不为空气的情况，且可适用于所述第四光栅部1132为空气或者不为空气的情况。当所述第二光栅部1112为不为空气且所述第四光栅部1132不空气时，即，所述第二光部由介质基材构成且所述第四光栅部1132由介质基材构成时，所述第一光栅层111与所述第二光栅层113贴合固定在一起，从而使得所述光栅110具有较薄的厚度。当所述第二光栅部1112及所述第四光栅部1132中的至少一个为空气时，所述第一光栅层111及所述第二光栅层113固定于所述承载基板115，且相背设置时，可使得所述光栅110形成较为稳固的整体，方便所述光栅110的应用。在本实施方式的示意图中，以所述光栅110还包括承载基板115结合到图13所示的实施方式中为例进行示意。
请参阅图15，图15为本申请另一实施方式提供的光栅的结构示意图。所述第一光栅层111包括周期性交替排布的第一光栅部1111及第二光栅部1112。其中，所述第一光栅部1111的折射率大于所述第二光栅部1112的折射率，所述第一光栅部1111的横截面的形状为第一矩形。所述第二光栅层113包括周期性交替排布的第三光栅部1131及第四光栅部1132。所述第三光栅部1131的折射率大于所述第四光栅部1132的折射率，且第三光栅部1131的至少部分对准所述第一光栅部1111设置。在本实施方式中，所述第一光栅层111及所述第二光栅层113通过连接层117连接为一个整体，且所述第一光栅层111及所述第二光栅层113设置于所述连接层117相背的两侧。换而言之，所述第一光栅层111、所述第二光栅层113及所述连接层117为一体结构。本实施方式的光栅110的结构，在减弱甚至消除彩虹纹的同时还降低了所述光栅110的制备时的工艺难度。
进一步地，在本实施方式中，所述第一光栅部1111、所述第二光栅部1112及所述连接层117的折射率相同。此外，所述第二光栅部1112及所述第四光栅部1132为气体。换而言之，第一光栅层111可看成包括间隔设置的多个第一光栅部1111，所述第二光栅层113可看成包括间隔气体设置的多个第三光栅部1131。在一实施方式中，所述第二光栅部1112的折射率与所述第四光栅部1132的折射率相同。在其他实施方式中，所述第二光栅部1112的折射率与所述第四光栅部1132的折射率不同。同样地，在本实施方式的示意图中以光线①表示入射至光栅110的光线，以光线②表示第一衍射光线，以光线③表示第二衍射光线。
在一种实施方式中，前面介绍的各个实施方式中的光栅110可为二元光栅110。当所述光栅110为二元光栅110时，所述第一光栅部1111的横截面为第一梯形且所述第三光栅部1131的横截面的形状为第二梯形的光栅110，相较于第一光栅部1111的横截面为第一矩形且所述第三光栅部1131的横截面的形状为第二矩形的光栅110在实际生产中更容易制备，具有更好的可加工性。
请参阅图16，图16为本申请一实施方式提供的光栅的结构示意图。在本实施方式中，所述光栅110包括周期性交替排布的多层第一光栅层111及第二光栅层113。换而言之，所述第一光栅层111及所述第二光栅层113作为可重复的光栅复合层110a，所述光栅110包括多个(图中示意出3个)光栅复合层110a。所述多个光栅复合层110a沿着所述第一光栅层111及所述第二光栅层113层叠的方向层叠设置。比如，当所述第一光栅层111及所述第二光栅层113沿着Z轴方向层叠设置时，所述多个光栅复合层110a沿着Z轴层叠设置。所述第一光栅层111及所述第二光栅层113的具体设置可参阅前面任意实施方式的描述，在此不再赘述。本实施方式的示意图中的第一光栅层111的具体结构及所述第二光栅层 113的具体结构仅为示意，不应当理解为对本申请实施方式提供的光栅110的限定。
由于所述所述第一光栅层111及所述第二光栅层113构成的光栅复合层110a可减小甚至避免彩虹纹，所述光栅110包括层叠设置的多个所述光栅复合层110a可进一步减弱彩虹纹。
请参阅图17，图17为本申请一实施方式提供的光栅和相关技术中的单层光栅的-1级透射效率的对比图。在仿真时，本申请的光栅110为包括第一光栅层111及第二光栅层113的双层光栅。在本对比图中，横轴为波长，单位为um；纵轴为透射效率，无单位。在本对比图中，虚线为本申请的光栅110的曲线，实线为单层光栅110的曲线。由本对比图可见，本申请的光栅110的-1级的透射效率比相关技术中的单层的光栅110的-1级的透射效率低。因此，本申请实施方式提供的光栅110相较于相关技术中的单层的光栅110可明显降低-1级的透射效率，由此可见，本申请实施方式提供的光栅110减弱甚至避免产生彩虹纹的效果较为明显。
请一并参阅图18及图19，图18为本申请一实施方式提供的光学器件的结构示意图；图19为具有TM偏振态的偏振片及具有TE偏振态的偏振片的-1级透射效率的对比图。所述光学器件10包括偏振片130及前述任意实施方式一项所述的光栅110，所述光栅110设置于所述偏振片130的一侧，且所述第一光栅层111相较于所述第二光栅层113背离所述偏振片130设置，所述偏振片130的偏振态为TM偏振态。所述偏振片130可与所述光栅110间隔设置，也可贴合所述光栅110设置。在图19中，横轴为波长，单位为um；纵轴为透射效率，无单位。图中实线为具有TM偏振态的偏振片130的-1级透射效率的曲线；图中的虚线为具有TE偏振态的偏振片130的-1级透射效率的曲线，由所述对比图可见，具有TM偏振态的偏振片130的-1级透射效率小于具有TE偏振态的偏振片130的-1级透射效率。因此，将具有TM偏振态的偏振片130设置于所述光栅110的一侧，且所述第一光栅层111相较于所述第二光栅层113背离所述偏振片130设置，可使得光线先经过偏振片130的作用，再经过第二光栅110至第一光栅110，因此，申请实施方式提供的光学器件10减弱甚至避免产生彩虹纹的效果较为明显。
在本实施方式中，所述偏振片130的尺寸大于或等于所述光栅110的尺寸，且所述光栅110在所述偏振片130上的正投影落入所述偏振片130内。
所述光学器件10中的偏振片130及所述光栅110的上述设置方式可使得光线在进入到光栅110之前有足够大的偏振片130先对光线进行作用，以进一步减弱甚至避免彩虹纹效应。
请参阅图20，图20为本申请一实施方式提供的增强现实显示装置的结构示意图。所述增强现实(Augmented Reality，AR)显示装置1包括前面任意实施方式所述的光栅110。或者，所述增强现实显示装置1包括前面任意实施方式所述的的光学器件10，其中，所述光学器件10中的光栅110为所述增强现实显示装置1中的耦出光栅。换而言之，所述增强现实显示装置1包括光栅110，且所述增强现实显示装置1可包括所述偏振片130也可不包括所述偏振片130。在本实施方式的示意图中，以所述增强现实显示装置1包括所述偏振片130及所述光栅为例进行示意。
所述光栅110为增强现实显示装置1中的耦出光栅时，前面各个实施方式介绍的所述光栅110对外界环境光的正常透射没有影响，且对增强现实显示装置1中包括所述耦出光栅在内的衍射波导的性能没有明显影响。
请参阅图21，图21为本申请一实施方式提供的增强现实显示装置的结构示意图。所述增强现实显示装置1可以为AR眼镜，也可以应用在汽车等具有挡风玻璃的设备上。在本实施方式的示意图中，以所述增强显示显示装置1为AR眼镜为例进行示意。所述增强现实显示装置1还包括佩戴框30。所述佩戴框30具有间隔设置的两个视窗区310，所述两个视窗区310的至少一个视窗区310设置有所述耦出光栅(即光栅110)及所述偏振片130。在本实施方式的示意图中，以所述两个视窗区310均设置有所述耦出光栅为例进行示意。需要说明的是，在本实施方式的示意图中，未示意出所述耦出光栅的具体形貌，所述耦出光栅的形貌请参阅前面任意实施方式介绍的光栅。
本文中应用了具体个例对本申请的原理及实施方式进行了阐述，以上实施例的说明只是用于帮助理解本申请的核心思想；同时，对于本领域的一般技术人员，依据本申请的思想，在具体实施方式及应用范围上均会有改变之处，综上所述，本说明书内容不应理解为对本申请的限制。

Claims (20)

  1. 一种光栅，其特征在于，所述光栅至少包括：
    第一光栅层，所述第一光栅层包括周期性交替排布的第一光栅部及第二光栅部，其中，所述第一光栅部的折射率大于所述第二光栅部的折射率，所述第一光栅部的横截面的形状为第一梯形；及
    第二光栅层，所述第二光栅层设置于所述第一光栅层的一侧，所述第二光栅层包括周期性交替排布的第三光栅部及第四光栅部，所述第三光栅部的折射率大于所述第四光栅部的折射率，且第三光栅部的至少部分对准所述第一光栅部设置，所述第三光栅部的横截面的形状为第二梯形，所述第二梯形的长边背离所述第一光栅部设置。
  2. 如权利要求1所述的光栅，其特征在于，所述第一光栅层与所述第二光栅层贴合固定在一起。
  3. 如权利要求1所述的光栅，其特征在于，所述第一光栅部的折射率的范围为1.4-3.0，所述第二光栅部的折射率的范围为1.0-2.0；所述第三光栅部的折射率范围为1.4-3.0，所述第四光栅部的折射率的范围为1.0-2.0。
  4. 如权利要求3所述的光栅，其特征在于，所述第二光栅部及所述第四光栅部包括如下情况中的至少一种：
    所述第二光栅部为空气；
    所述第四光栅部为空气。
  5. 如权利要求4所述的光栅，其特征在于，所述光栅还包括：
    承载基板，所述第一光栅层及所述第二光栅层固定于所述承载基板，且相背设置。
  6. 如权利要求1所述的光栅，其特征在于，所述第一梯形及第二梯形均为等腰梯形，且所述第一梯形及所述第二梯形包括如下情况中的至少一种：
    所述第一梯形的长边与所述第一梯形的腰之间的夹角大于80°；
    所述第二梯形的长边与所述第二梯形的腰之间的夹角大于80°。
  7. 如权利要求1所述的光栅，其特征在于，所述第一梯形的长边的端点在第二梯形的长边所在的平面上的正投影与所述第二梯形的长边中邻近所述第一梯形的端点完全重合。
  8. 如权利要求1所述的光栅，其特征在于，第一梯形的长边在所述第二梯形的长边所在的平面上的正投影与所述第二梯形的长边至少部分重合；或者，所述第一梯形的长边在所述第二梯形的长边所在的平面上的正投影与所述第二梯形的长边间隔设置。
  9. 如权利要求1所述的光栅，其特征在于，所述第一光栅层的高度范围为10nm-1um，所述第二光栅层的高度范围为10nm-1um。
  10. 如权利要求1所述的光栅，其特征在于，所述第一光栅层的周期与所述第二光栅层的周期相同，且所述第一光栅层的周期为300nm-600nm，所述第二光栅层的周期为300nm-600nm。
  11. 如权利要求1-8任意一项所述的光栅，其特征在于，所述光栅包括周期性交替排布的多层第一光栅层及第二光栅层。
  12. 一种光栅，其特征在于，所述光栅至少包括：
    第一光栅层，所述第一光栅层用于对光线进行衍射，以得到第一衍射光线；及
    第二光栅层，所述第二光栅设置于所述第一光栅层的一侧，用于对所述光线进行衍射，以得到第二衍射光线，其中，所述第二衍射光线及所述第一衍射光的相位差P的范围为：(2N+1)π-π/2≤P≤(2N+1)π+π/2，其中N≥0，且N为整数。
  13. 如权利要求12所述的光栅，其特征在于，所述第一光栅层包括周期性交替排布的第一光栅部及第二光栅部，其中，所述第一光栅部的折射率大于所述第二光栅部的折射率，所述第一光栅部的横截面的形状为第一梯形；
    所述第二光栅层包括周期性交替排布的第三光栅部及第四光栅部，所述第三光栅部的折射率大于所述第四光栅部的折射率，且第三光栅部的至少部分对准所述第一光栅部设置，所述第三光栅部的横截面的形状为第二梯形，所述第二梯形的长边背离所述第一光栅部设置。
  14. 如权利要求13所述的光栅，其特征在于，所述第一光栅部的折射率的范围为1.4-3.0，所述第二光栅部的折射率的范围为1.0-2.0；所述第三光栅部的折射率范围为1.4-3.0，所述第四光栅部的折射率的范围为1.0-2.0。
  15. 如权利要求12所述的光栅，其特征在于，所述第一光栅层的高度范围为10nm-1um，所述第二光栅层的高度范围为10nm-1um。
  16. 如权利要求12所述的光栅结构，其特征在于，所述第一光栅层的周期与所述第二光栅层的周期相同，且所述第一光栅层的周期为300nm-600nm，所述第二光栅层的周期为300nm-600nm。
  17. 一种光学器件，其特征在于，所述光学器件包括偏振片及权利要求1-16任意一项所述的光栅，所述光栅设置于所述偏振片的一侧，且所述第一光栅层相较于所述第二光栅层背离所述偏振片设置，所述偏振片的偏振态为TM偏振态。
  18. 如权利要求17所述的光学器件，其特征在于，所述偏振片的尺寸大于或等于所述光栅的尺寸，且所述光栅在所述偏振片上的正投影落入所述偏振片内。
  19. 一种增强现实显示装置，其特征在于，所述增强现实显示装置包括如权利要求1-16任意一项所述的光栅，或者，所述增强现实显示装置包括如权利要求17-18任意一项所述的光学器件，其中，所述光栅为所述增强现实显示装置中的耦出光栅。
  20. 如权利要求19所述的增强现实显示装置，其特征在于，所述增强现实显示装置还包括：
    佩戴框，所述佩戴框具有间隔设置的两个视窗区，所述两个视窗区的至少一个视窗区设置有所述耦出光栅。
PCT/CN2022/071848 2021-02-09 2022-01-13 光栅、光学器件及增强现实显示装置 WO2022170912A1 (zh)

Priority Applications (2)

Application Number Priority Date Filing Date Title
EP22752074.9A EP4279962A4 (en) 2021-02-09 2022-01-13 AUGMENTED REALITY NETWORK, OPTICAL DEVICE AND DISPLAY DEVICE
US18/362,567 US20240019616A1 (en) 2021-02-09 2023-07-31 Grating and optical device

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN202110177022.5 2021-02-09
CN202110177022.5A CN112987156A (zh) 2021-02-09 2021-02-09 光栅、光学器件及增强现实显示装置

Related Child Applications (1)

Application Number Title Priority Date Filing Date
US18/362,567 Continuation US20240019616A1 (en) 2021-02-09 2023-07-31 Grating and optical device

Publications (1)

Publication Number Publication Date
WO2022170912A1 true WO2022170912A1 (zh) 2022-08-18

Family

ID=76392576

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2022/071848 WO2022170912A1 (zh) 2021-02-09 2022-01-13 光栅、光学器件及增强现实显示装置

Country Status (4)

Country Link
US (1) US20240019616A1 (zh)
EP (1) EP4279962A4 (zh)
CN (1) CN112987156A (zh)
WO (1) WO2022170912A1 (zh)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112987156A (zh) * 2021-02-09 2021-06-18 Oppo广东移动通信有限公司 光栅、光学器件及增强现实显示装置
CN114839713B (zh) * 2022-05-18 2024-04-02 南京工业职业技术大学 一种基于头盔显示的二维扩瞳全息波导结构

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101548214A (zh) * 2006-10-24 2009-09-30 郑庆姬 光学组件、使用光学组件的光学传感器以及光学组件的制造方法
CN104956148A (zh) * 2012-09-20 2015-09-30 芬兰国家技术研究中心股份公司 具有衍射光栅的光学器件
US20190369309A1 (en) * 2018-06-05 2019-12-05 Globalfoundries Inc. Grating couplers with multiple configurations
US20200041791A1 (en) * 2018-08-03 2020-02-06 Facebook Technologies, Llc Rainbow reduction for waveguide displays
CN112987156A (zh) * 2021-02-09 2021-06-18 Oppo广东移动通信有限公司 光栅、光学器件及增强现实显示装置

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2864252B1 (fr) * 2003-12-23 2006-04-07 Jobin Yvon Sas Reseau de diffraction a empilements multicouches alternes et son procede de fabrication et dispositifs spectroscopiques comportant ces reseaux
DE602005012105D1 (de) * 2005-09-26 2009-02-12 Suisse Electronique Microtech Hitze reflektierende Scheibe mit Beugungsfilter nullter Ordnung
JP2008257771A (ja) * 2007-04-02 2008-10-23 Ricoh Co Ltd 光ピックアップ
JP2017004004A (ja) * 2012-03-26 2017-01-05 旭硝子株式会社 透過型回折素子
JP2018146624A (ja) * 2017-03-01 2018-09-20 Ａｇｃ株式会社 透過型回折素子および反射防止構造
CN108387960A (zh) * 2018-03-22 2018-08-10 上海鲲游光电科技有限公司 可用于增强现实眼镜的多层结构光栅

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101548214A (zh) * 2006-10-24 2009-09-30 郑庆姬 光学组件、使用光学组件的光学传感器以及光学组件的制造方法
CN104956148A (zh) * 2012-09-20 2015-09-30 芬兰国家技术研究中心股份公司 具有衍射光栅的光学器件
US20190369309A1 (en) * 2018-06-05 2019-12-05 Globalfoundries Inc. Grating couplers with multiple configurations
US20200041791A1 (en) * 2018-08-03 2020-02-06 Facebook Technologies, Llc Rainbow reduction for waveguide displays
CN112987156A (zh) * 2021-02-09 2021-06-18 Oppo广东移动通信有限公司 光栅、光学器件及增强现实显示装置

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP4279962A4 *

Also Published As

Publication number Publication date
EP4279962A4 (en) 2024-07-31
EP4279962A1 (en) 2023-11-22
CN112987156A (zh) 2021-06-18
US20240019616A1 (en) 2024-01-18

Similar Documents

Publication Publication Date Title
WO2022170912A1 (zh) 光栅、光学器件及增强现实显示装置
WO2023040491A1 (zh) 光学结构和光学装置
US10095045B2 (en) Waveguide comprising a bragg polarization grating
US8529114B2 (en) Sheet and light emitting device
US8611014B2 (en) Optical waveguide and display device
KR20190015507A (ko) 도파관 구조체
US20080252825A1 (en) Nano wire grid polarizer and liquid crystal display apparatus employing the same
CN110824613A (zh) 偏振复用波导显示器件
JP2023526430A (ja) 広視野を伴う二重プロジェクタ導波管ディスプレイのための方法およびシステム
JPWO2010131430A1 (ja) シート及び発光装置
JPWO2011099550A1 (ja) 光学素子及び光学系
CN113534326B (zh) 一种偏振复用高衍射效率波导显示器件
KR20120004452A (ko) 광학 소자, 편광 필터, 광 아이솔레이터 및 광학 장치
JP5511674B2 (ja) シートおよび発光装置
WO2018195983A1 (zh) 一种光波导结构及光学系统
WO2023185663A1 (zh) 光学器件和ar设备
JP5245911B2 (ja) スクリーン
US7305155B2 (en) Optical element and wavelength separator using the same
CN113552721A (zh) 波导结构和头戴显示设备
JP5921251B2 (ja) 液晶レンズ
KR100926334B1 (ko) 광기능성 필름
JP2010085964A (ja) 光学シート
WO2023005418A1 (zh) 光学结构和光学装置
JPWO2019107249A1 (ja) 光学素子および導光素子
WO2022170910A1 (zh) 增强现实显示装置及近眼显示设备

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 22752074

Country of ref document: EP

Kind code of ref document: A1

WWE Wipo information: entry into national phase

Ref document number: 2022752074

Country of ref document: EP

ENP Entry into the national phase

Ref document number: 2022752074

Country of ref document: EP

Effective date: 20230817

NENP Non-entry into the national phase

Ref country code: DE