Display Components

Abstract

According to one embodiment, the display component 100 includes a waveguide 104, an incoupling structure 101 configured to couple input beams 901 into the waveguide 104 as a first set of incoupling beams 110 corresponding to a first set of incoupling k-vectors 204_1 in a first region 205_1 of k-space, a hexagonal diffraction grating, and diffracts the first set of incoupling beams 110 into a first plurality of directions 206 in k-space to form a first set of three regions 205_1. The optical waveguide includes an exit pupil extension structure 102 configured to form three guided beam groups corresponding to the three k-vector groups 204_1, 204_2, 204_3 present in the first three region groups 205_1, 205_2, 205_3, and an outcoupling structure 103 configured to receive a first diffracted beam group 111 corresponding to the diffracted k-vector group present in at least one of the first three region groups 205_1, 205_2, 205_3, and to outcouple the first diffracted beam group 111 from the waveguide plate 104.

Description

[Technical field]

[0001] The present disclosure relates to the field of diffractive optics, and more particularly to display components and display devices. [Background technology]

[0002] The production of small form factor augmented reality (AR) glasses requires miniature projectors, such as laser projectors. The waveguides used in AR glasses currently have technical challenges in terms of achieving high light effects while simultaneously obtaining uniform images with laser projectors. Some waveguide designs achieve good uniformity but poor efficiency, while other designs offer better efficiency but poor uniformity. Summary of the Invention

[0003] This Summary is provided to introduce in a simplified form selected concepts that are further described below in the Detailed Description. This Summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.

[0004] It is an object of the present disclosure to provide a display component and a display device. These and other objects are achieved by the characterizing elements of the independent claims. Further embodiments are evident from the dependent claims, the description and the figures.

[0005] According to a first aspect, a display component comprises a waveguide; an incoupling structure configured to couple input beams into the waveguide as a first group of incoupling beams corresponding to a first group of incoupling k-vectors present in a first region of k-space within an annular waveguide propagation region associated with the waveguide; an exit pupil extension structure comprising a diffraction grating and configured to receive the first group of incoupling beams and diffract the first group of incoupling beams in a first plurality of directions in k-space to form three group of guided beams corresponding to three group of k-vectors present in a first group of three regions within the annular waveguide propagation region including a first region; and an outcoupling structure configured to receive from the exit pupil extension structure a first group of diffracted beams corresponding to a group of diffracted k-vectors present in at least one region of the first group of three regions and outcouple the first group of diffracted beams from the waveguide as output beams.

[0006] According to a second aspect, a display device comprises a display component according to the first aspect.

[0007] Many of the attendant features will be more readily appreciated as the same becomes better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings.

[0008] In the following, exemplary embodiments are described in more detail with reference to the accompanying drawings. [Brief description of the drawings]

[0009] [Figure 1] FIG. 2 is a schematic diagram of a display component according to one embodiment. [Diagram 2] FIG. 13 is a k-space diagram of a beam diffracted by an in-coupling structure and an exit pupil extension structure in accordance with one embodiment. [Diagram 3] FIG. 1 is a k-space diagram of a beam diffracted by an exit pupil extension structure in accordance with one embodiment. [Figure 4]FIG. 13 is a k-space diagram of a beam diffracted by an in-coupling structure and an exit pupil extension structure in accordance with one embodiment. [Diagram 5] FIG. 1 is a k-space diagram of a beam diffracted by an outcoupling structure according to an embodiment; [Figure 6] FIG. 13 is a k-space diagram of a beam further diffracted by an exit pupil extension structure in accordance with one embodiment. [Figure 7] 2 is a schematic diagram of a grating structure of a diffraction grating according to one embodiment; [Figure 8] 1 is a schematic diagram of a beam within an exit pupil expansion structure according to one embodiment; [Figure 9] FIG. 2 is a schematic diagram of the correspondence between input and output beam groups. [Figure 10] 1 is a schematic diagram of simulation results according to several examples. [Figure 11] 11 is a schematic diagram of simulation results according to further embodiments. [Figure 12] 11 is a schematic diagram of simulation results according to further embodiments. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] In the following, identical reference signs refer to similar or at least functionally equivalent features.

[0011] In the following description, reference will be made to the accompanying drawings, which form a part of the disclosure, and in which are shown by way of illustration certain aspects in which the present disclosure may be embodied. It is understood that other aspects may be utilized, and changes in structure or logic may be made without departing from the scope of the present disclosure. Accordingly, the following detailed description is not to be taken in a limiting sense, as the scope of the present disclosure is defined by the appended claims.

[0012] For example, it is understood that disclosure related to a described method may also apply to a corresponding apparatus or system configured to perform the method, and vice versa. For example, if a particular method step is described, a corresponding apparatus may include parts for performing the described method step, even if such parts are not explicitly described or shown in the figures. On the other hand, for example, if a particular apparatus is described based on functional parts, a corresponding method may include steps for performing the described function, even if such steps are not explicitly described or shown in the figures. Furthermore, it is understood that features of various exemplary aspects described herein can be combined with each other, unless individually noted otherwise.

[0013] FIG. 1 shows a schematic diagram of a display component according to one embodiment.

[0014] According to one embodiment, the display component 100 comprises a waveguide 104 and an incoupling structure 101 configured to couple input beams into the waveguide 104 as first incoupling beams 110 corresponding to first incoupling k-vectors existing in a first region of k-space within an annular waveguide propagation region associated with the waveguide 104.

[0015] In this specification, a beam may be referred to as an electromagnetic beam, a light beam, a ray, or the like.

[0016] The input beams may be generated, for example, by a scanner-based light engine. The input beams may represent, for example, an image generated by such a light engine.

[0017] The waveguide 104 may be, for example, a substantially planar waveguide. For example, the waveguide may correspond to a lens of an augmented reality (AR) glass.

[0018] The in-coupling structure 101 may for example comprise a diffraction grating on the surface of a waveguide, and thus the in-coupling structure 101 can couple the input beams into the waveguide 104 by diffraction.

[0019] The display component 100 may further include an exit pupil expansion (EPE) structure 102 comprising a diffraction grating and configured to receive the first incoupling beam group 110 and diffract the first incoupling beam group 110 into a first plurality of directions in k-space to form three guided beam groups corresponding to three k-vector groups present in a first group of three regions within the annular waveguide propagation region, including the first region.

[0020] The diffraction grating of the EPE structure 102 can be disposed on at least one surface of the waveguide 104, for example.

[0021] The display component 100 may further include an outcoupling structure 103 configured to receive from the EPE structure 102 a first group of diffracted beams 111 corresponding to diffracted k-vectors present in at least one of the first three groups of regions, and to outcouple the first group of diffracted beams 111 from the waveguide 104 as output beams.

[0022] The outcoupling structure 103 may for example comprise a diffraction grating on a surface of the waveguide. The outcoupling structure 103 is thus able to outcouple the first diffracted beams 111 from within the waveguide 104 by diffraction.

[0023] The output beams may, for example, represent a magnification of the image formed by the input beams.

[0024] It should be understood that the geometry of the display component 100 shown in the embodiment of FIG. 1 is merely exemplary, and that the display component 100 may be embodied in a variety of other forms.

[0025] According to one embodiment, a display device comprises a display component 100 .

[0026] The display device may comprise a scanner-based light engine, for example a laser scanning light engine, for directing the input beams to the incoupling structure 101.

[0027] The display device may for example be implemented as a see-through display device.

[0028] The display device may for example be implemented as a head mounted display device.

[0029] FIG. 2 shows a k-space diagram of a beam diffracting at an exit pupil extension structure according to one embodiment.

[0030] As used herein, annular waveguide propagation region 201 may refer to a portion of k-space in which a beam is guided within waveguide 104. An example of an annular waveguide propagation region 201 is shown in the embodiment of FIG.

[0031] Each k-vector in k-space can represent the propagation direction of a beam within the waveguide 104. The magnitude of each k-vector corresponds to the wave number k. The k-vector can be expressed as:

number

number

[0032] The waveguide 104 can guide beams with a particular k-vector by total internal reflection (TIR). The coupling region 202 corresponds to k-vectors that do not have enough x and / or y components to be guided in the waveguide by TIR, where the x and y axes are in the plane of the waveguide 104, but the z axis is along the thickness of the waveguide 104. Such beams do not have a sufficient angle between the beam and the surface of the waveguide 104 for TIR to occur as governed by Snell's law. The k-vectors in the annular waveguide propagation region 201 have enough x and / or y components to be guided in the waveguide by TIR. The k-vectors on the periphery of the annular waveguide propagation region 201 correspond to beams that propagate along the plane of the waveguide 104, i.e., such beams do not have any z-component. The radius of the coupling region 202 can be 1, and the radius of the annular waveguide propagation region 201 can be n.

[0033] The incoupling structure 101 can couple the input beams into the waveguide 104 as first incoupling beams 110 corresponding to first incoupling k-vectors 204_1 residing in a first region 205_1 of k-space.

[0034] For example, in the embodiment of Fig. 2, k-vectors 203 corresponding to input beams are located in a coupling region 202 of k-space. The incoupling structure 101 can couple the input beams into the waveguide 104 as first incoupling beams 110 corresponding to a first incoupling k-vector group 204_1 located in a first region 205_1 of k-space.

[0035] The incoupling structure 101 may comprise, for example, a diffraction grating that can couple input beams into the waveguide 104. As can be seen from the embodiment of Fig. 2, the first incoupling k-vectors 204_1 are in the annular waveguide propagation region 201, so that the corresponding first incoupling beams 110 are guided in the waveguide 104 by TIR.

[0036] Different k-vectors in the first incoupling k-vector group 204_1 may correspond to different colors and / or different portions of an image represented by the input beams, for example. For example, the input beams may include green, blue, and red frequency bands. Each such frequency band may have a different wavelength / frequency, and therefore each color may occupy a different portion of k-space. For example, in the embodiment of FIG. 2, each of the three rectangles in the first incoupling k-vector group 204_1 may correspond to a frequency band of an image represented by the input beams.

[0037] The EPE structure 102 can receive the first incoupling beam group 110 and diffract the first incoupling beam group 110 into a first plurality of directions 206 in k-space to form three guided beam groups corresponding to three k-vector groups 204_1, 204_2, 204_3 present in a first three region group 205_1, 205_2, 205_3 in the annular waveguide propagation region 201, including the first region 205_1.

[0038] The outcoupling structure 103 can receive from the EPE structure 102 a first group of diffracted beams 111 corresponding to a group of diffracted k-vectors present in at least one of the first three region groups 205_1, 205_2, 205_3, and outcouple the first group of diffracted beams 111 from the waveguide as output beams.

[0039] The outcoupling structure 103 may, for example, comprise a diffraction grating capable of outcoupling the first diffracted beams as output beams from the waveguide 104. In k-space terms, this can be illustrated as the outcoupling structure 103 diffracting diffracted k-vectors present in at least one of the first three regions 205_1, 205_2, 205_3 into the coupling region 202 of k-space.

[0040] According to one embodiment, the EPE structure 102 is configured to diffract the first incoupling beam group in zeroth and first diffraction orders to form three guided beam groups corresponding to three k-vector groups 204_1, 204_2, 204_3 present in the first three region groups 205_1, 205_2, 205_3.

[0041] According to one embodiment, the EPE structure 102 is configured to only diffract the first incoupling beam group in zeroth and first diffraction orders to form three guided beam groups corresponding to three k-vector groups 204_1, 204_2, 204_3 present in the first three region groups 205_1, 205_2, 205_3.

[0042] According to one embodiment, the waveguide propagation region 201 surrounds the coupling region 202, and the first three groups of regions 205_1, 205_2, 205_3 form a triangle, such as an equilateral triangle or an isosceles triangle, that at least partially overlaps the coupling region 202. Since the three groups of k-vectors 204_1, 204_2, 204_3 are within the annular waveguide propagation region 201, such diffraction by the EPE structure 102 can reduce optical loss.

[0043] In some embodiments disclosed herein, the k-vectors 203 corresponding to the input beams are located at the origin of k-space, but this may not be the case in all embodiments. For example, if the input beams are not perpendicular to the waveguide 104, the k-vectors 203 corresponding to the input beams may be located somewhere else in the coupling region 202.

[0044] FIG. 3 shows a k-space diagram of a beam diffracting at an exit pupil extension structure according to another embodiment.

[0045] According to one embodiment, the incoupling structure 101 is further configured to couple the input beam group into the waveguide as a second incoupling beam group corresponding to a second incoupling k-vector group 304_1 existing in a second region 305_1 of k-space different from the first region 205_1 within the annular waveguide propagation region 201 associated with the waveguide.

[0046] The EPE structure 102 may be further configured to receive the second incoupling beam group and diffract the second incoupling beam group into a second plurality of directions 306 in k-space to form three guided beam groups corresponding to three k-vector groups 304_1, 304_2, 304_3 present in a second three region group 305_1, 305_2, 305_3 different from the first three region group 205_1, 205_2, 205_3 in the annular waveguide propagation region 201, including the second region 305_1.

[0047] The first plurality of directions 206 and the second plurality of directions 306 may be due to the same diffraction, but because the first and second incoupling beam groups propagate in different directions, the same diffraction results in the k-vectors for the first incoupling beam group being present in the first three region groups 205_1, 205_2, 205_3, and the k-vectors for the second incoupling beam group being present in the second three region groups 305_1, 305_2, 305_3.

[0048] The outcoupling structure 103 may be further configured to receive a second group of diffracted beams from the EPE structure 102 corresponding to diffracted k-vectors present in at least one of the second three region groups 305_1, 305_2, 305_3, and to outcouple the second group of diffracted beams from the waveguide as output beams.

[0049] FIG. 4 shows a k-space diagram of a beam diffracted by an incoupling structure according to one embodiment.

[0050] According to one embodiment, the incoupling structure 101 comprises a one-dimensional diffraction grating.

[0051] The incoupling structure 101, which has a one-dimensional diffraction grating, can diffract the input beams into two opposite propagation directions in the waveguide 104. If the incoupling structure 101 is located near the edge of the waveguide 104, the incoupling beams traveling in one of these propagation directions may be substantially lost at the edge of the waveguide 104, and only the incoupling beams traveling in the other propagation direction can be received by the EPE structure 102.

[0052] If the geometry of the waveguide 104 is such that both of the two propagation directions can be received by the EPE structure 102, the incoupling beams can function as a first incoupling beam group and a second incoupling beam group. A k-space representation of such a situation is illustrated in the embodiment of FIG. 4. The EPE structure 102 can then diffract the first incoupling beam group and the second incoupling beam group as disclosed herein, resulting in the formation of three guided beam groups corresponding to the three k-vector groups 204_1, 204_2, 204_3 present in the first three region groups 205_1, 205_2, 205_3, and three guided beam groups corresponding to the three k-vector groups 304_1, 304_2, 304_3 present in the second three region groups 305_1, 305_2, 305_3.

[0053] FIG. 5 shows a k-space diagram of a beam diffracted by an outcoupling structure according to one embodiment.

[0054] According to one embodiment, the EPE structure 102 is located on a first side of the waveguide plate 104, and the outcoupling structure 103 is located on a second side of the waveguide plate 104, and the outcoupling structure 103 comprises a one-dimensional diffraction grating. The EPE structure 102 and the outcoupling structure 103 may be at least partially aligned. For example, the EPE structure 102 and the outcoupling structure 103 may be similar in shape and / or area and may be substantially aligned. Alternatively, the EPE structure 102 may have a larger surface area than the outcoupling structure 103, and the area of ​​the outcoupling structure 103 may be a lower area of ​​the EPE structure 102. Alternatively, the outcoupling structure 103 may have a larger surface area than the EPE structure 102, and the area of ​​the EPE structure 102 may be a lower area of ​​the outcoupling structure 103.

[0055] The embodiment of Fig. 5 illustrates a k-space representation of outcoupling in the one-dimensional outcoupling structure 103. In the embodiment of Fig. 5, the outcoupling structure 103 outcouples a first group of diffracted beams associated with a group of diffracted k-vectors present in one of the first three groups of regions 205_1, 205_2, 205_3, and a second group of diffracted beams associated with a group of diffracted k-vectors present in one of the second three groups of regions 305_1, 305_2, 305_3.

[0056] The outcoupling structure 103 can perform outcoupling by diffracting the first diffracted beam group and the second diffracted beam group in a direction 501 in k-space such that k-vectors from one region 205_3 among the first three region groups 205_1, 205_2, 205_3 and one region 305_3 among the second three region groups 305_1, 305_2, 305_3 are diffracted into the coupling region 202.

[0057] Since the first region 205_1 corresponds to the propagation direction of the incoupling beam 110, the first region 205_1 corresponds to a so-called direct beam. If the direct beam is outcoupled without diffraction in the EPE structure 102, bright stripes may be observed in the output image. If the outcoupling structure 103 does not outcouple the direct beam, this problem can be avoided.

[0058] Alternatively, or in addition, bright fringes can be mitigated by placing the outcoupling structure 103 between the two propagation directions of the incoupling structure 101.

[0059] FIG. 6 shows a k-space diagram of a beam further diffracted by an exit pupil extension structure according to one embodiment.

[0060] In one embodiment, the diffraction grating of the EPE structure 102 is located on a first surface of the waveguide 104, and the EPE structure 102 is further provided with a one-dimensional diffraction grating on a second surface of the waveguide so as to generate further diffraction between two of the first set of three regions and / or between two of the second set of three regions.

[0061] For example, in the embodiment of Figure 6, the EPE structure 102 further comprises a one-dimensional grating on the second surface of the waveguide 104. As can be seen from the k-space representation, the one-dimensional grating on the other surface enhances the directional changes between certain propagation directions.

[0062] In any of the embodiments disclosed herein, the edge of the waveguide 104 may include a number of diffraction gratings, such as one-dimensional diffraction gratings, configured to return any light back to the center of the waveguide 104. These diffraction gratings may be present on the first and / or second surface of the waveguide 104.

[0063] FIG. 7 shows a schematic diagram of a grating structure of a diffraction grating according to one embodiment.

[0064] As used herein, a hexagonal diffraction grating can refer to a diffraction grating that is a two-dimensional hexagonal lattice structure. The hexagonal lattice has an angle of 60° between the primitive lattice vectors 705, 706, and the primitive lattice vectors 705, 706 are the same length.

[0065] It should be understood that the production of a lattice structure may be constrained by the manufacturing method used, and therefore any lattice having the above characteristics within the tolerances of the manufacturing method used may be considered to be a hexagonal lattice.

[0066] It should be understood that the embodiment of FIG. 7 may not represent the physical structure of a diffraction grating. Rather, the embodiment of FIG. 7 represents an example of the periodicity and orientation of a diffraction grating based on the primitive grating vectors 705, 706, 707, 708. For example, the diffraction grating may comprise ridges / rules, and the primitive grating vectors 705, 706, 707, 708 may correspond to the spatial periodicity and orientation of these ridges / rules. For example, such ridges / rules may be drawn along the grating element. Thus, the spatial periodicity of the ridges / rules, i.e., the distance between two adjacent ridges / rules, may be perpendicular to the primitive grating vector. The structure of these ridges / rules defines the diffraction generated by the diffraction grating.

[0067] According to one embodiment, the incoupling structure 101 comprises an incoupling grating for coupling the input beam group into the waveguide plate, and / or the outcoupling structure 103 comprises an outcoupling grating for outcoupling the first diffracted beam group and / or the second diffracted beam group from the waveguide plate.

[0068] According to one embodiment, the incoupling structure 101 is a fundamental lattice vector a IC 707 and b IC 708, the exit pupil extension structure 102 includes a spatially periodic diffraction grating having a fundamental grating vector a EPE 705 and b EPE 706, a spatially periodic diffraction grating having a IC, b IC The angle between and a EPE , b EPE The angle between them is less than 90 degrees, IC =2a EPE -b EPE and b IC =a EPE +b EPE It is.

[0069] An example of the grating structure of the diffraction grating of the incoupling structure 101 and the EPE structure 102 is shown in the embodiment of Figure 7. The grating elements with black circles form the grating structure of the incoupling structure 101, while the grating elements with black circles and the grating elements with white circles form the grating structure of the EPE structure 102.

[0070] Although the lattice structure of the EPE structure is illustrated as hexagonal in the embodiment of FIG. 7, this is by way of example only and the lattice structure can take a variety of other shapes.

[0071] Although the primitive grating vectors 705, 706, 707, 708 of the EPE structure 102 and the incoupling structure 101 are shown as one grating in the embodiment of Figure 7, this is for illustrative purposes only. Typically, the grating of the EPE structure 102 is a separate structure from the grating of the incoupling structure 101.

[0072] The primitive lattice vectors may be chosen differently for both the in-coupling structure 101 and the EPE structure 102, which allows the relationship between the primitive vectors to be different.

[0073] According to the above-mentioned relationship between the fundamental vectors 705, 706 of the EPE structure 102 and the fundamental vectors 707, 708 of the incoupling structure 101, the EPE structure 102 can have six propagation directions, two for each incoupling beam group, with substantially no outcoupling. An example of this is shown in the k-space representation in the embodiment of Fig. 3. Due to the reduced outcoupling at the EPE structure 102, the light efficiency of the display component 100 can be improved.

[0074] In some embodiments, the incoupling structure 101 may comprise some other type of grating, such as a one-dimensional grating, in such an embodiment, the grating of the EPE structure 102 may be rotated with respect to the propagation direction of the first incoupling beams 110.

[0075] According to one embodiment, the angle between the propagation direction of the first incoupling beam group 110 and at least one grating vector of the diffraction grating of the EPE structure 102 is in the range of 12 to 38 degrees, 12 to 30 degrees, 15 to 30 degrees, or 20 to 30 degrees.

[0076] According to one embodiment, the EPE structure 102 comprises a diffraction grating in which the angle between the primitive lattice vectors of the diffraction grating is in the range of 21 to 91 degrees and the ratio of the lengths of the lattice vectors is in the range of 0.62 to 1. Such a diffraction grating can be called a modified hexagonal lattice, etc. Alternatively, the angle between the primitive lattice vectors of the diffraction grating can be in the range of 25 to 85 degrees, 36 to 76 degrees, 40 to 70 degrees, 45 to 70 degrees, 50 to 70 degrees, or 55 to 65 degrees.

[0077] FIG. 8 shows a schematic diagram of a beam within an exit pupil expansion structure according to one embodiment.

[0078] The embodiment of FIG. 8 may correspond to a k-space representation of the embodiment of FIG.

[0079] As the first group of incoupling beams 110 propagate through the waveguide 104 by TIR, each time the beam strikes the surface of the waveguide 104 having the diffraction grating of the EPE structure 102, the beam can interact with the diffraction grating.

[0080] Each time the beam interacts with the diffraction grating of the EPE structure 102, the beam is diffracted. For example, in the embodiment of Fig. 8, at each interaction point, part of the beam is diffracted in two directions and part is reflected by the grating to continue along its original propagation direction. The propagation directions correspond to the directions shown in the k-space representation of the embodiment of Fig. 2. Thus, the EPE structure 102 can magnify the original image represented by the first group of incoupling beams.

[0081] In the embodiment of FIG. 8, one incoupling beam group reaches the EPE structure 102. If a second incoupling beam group reaches the EPE structure 102, more propagation directions can be observed. For example, for the propagation directions shown in the embodiment of FIG. 3, there are propagation directions opposite to each of the propagation directions shown in the embodiment of FIG. 8.

[0082] FIG. 9 shows a schematic diagram of the correspondence between the input and output beam groups.

[0083] The outcoupling structure 103 can outcouple light from the waveguide 104 whenever the light interacts with the outcoupling structure 103. Thus, the image can be magnified and outcoupled by the outcoupling structure 103.

[0084] Beam 910 of input beam group 901, which corresponds to the central portion of the image, can be converted into a corresponding output beam 920 of output beam group 902, aligned along an optical axis perpendicular to the exit pupil 940 of the waveguide 104.

[0085] Beam 911 of input beam group 901, which corresponds to the right portion of the image, can be converted to a corresponding output beam 921 of output beam group 902 that exits waveguide 104 at an angle such that it appears to originate from a position in the right portion of the field of view of user 903. Similarly, beam 912 of input beam group 901, which corresponds to the left portion of the image, can be converted to a corresponding output beam 922 of output beam group 902 that exits waveguide 104 at an angle such that it appears to originate from a position in the left portion of the field of view of user 903.

[0086] Although beams 920, 921, 922 of output beam set 902, which correspond to different portions of the image, are shown as outputting from a single point on waveguide 104 for illustrative purposes only, in reality each of beams 920, 921, 922 may output from a different portion of waveguide 104.

[0087] The multiple output beams in output beam group 902 that correspond to a particular point in the image may include beams propagating along parallel paths, as shown in the embodiment of Figure 9, or diverging paths. In the former case, the image will be projected to appear to emanate from optical infinity, while in the latter case, the image will be projected to appear to emanate from some finite distance.

[0088] Thus, the display component 100 can incouple and guide the input beams 901 to form an exit pupil 940 that is larger than the entrance pupil 930. The display component 100 can convert a given input beam having a particular angle in the input beams 901 into a corresponding number of beams in the output beams 902 that have angles relative to the particular input beam and are output across the exit pupil 940.

[0089] Both the EPE structure 102 and the outcoupling structure 103 can be configured to magnify the image. For example, the EPE structure 102 can magnify the image in one direction, as in the embodiment of Fig. 8, and the outcoupling structure 103 can magnify the image in a direction perpendicular to said direction, as in the embodiment of Fig. 9. Alternatively, the EPE structure 102 can be configured to magnify the image in two mutually perpendicular directions, and the outcoupling structure 103 can be configured to outcouple light from the waveguide 104.

[0090] FIG. 10 shows a schematic diagram of simulation results according to several embodiments.

[0091] The leftmost k-space representation 1001 illustrates the diffraction caused by the incoupling structure 101 having a one-dimensional diffraction grating. The other k-space representations 1002-1005 illustrate the diffraction caused by EPE structures 102 having different grating arrangements when the EPE structure 102 receives the first group of incoupling beams diffracted by the incoupling structure 101 having the one-dimensional diffraction grating.

[0092] The k-space representation 1002 corresponds to an EPE structure 102 having a lattice structure with a lattice vector length ratio of 0.94 and an angle between the lattice vectors of 122°.

[0093] The k-space representation 1003 corresponds to an EPE structure 102 having a lattice structure with a lattice vector length ratio of 0.87 and an angle between the lattice vectors of 116°.

[0094] The k-space representation 1004 corresponds to an EPE structure 102 having a lattice structure with a lattice vector length ratio of 0.81 and an angle between the lattice vectors of 128°.

[0095] The k-space representation 1005 corresponds to an EPE structure 102 having a lattice structure with a lattice vector length ratio of 0.76 and an angle between the lattice vectors of 112°.

[0096] FIG. 11 shows a schematic diagram of simulation results according to further embodiments.

[0097] The leftmost k-space representation 1101 illustrates the diffraction caused by the incoupling structure 101 having a one-dimensional diffraction grating. The other k-space representations 1102-1105 illustrate the diffraction caused by EPE structures 102 having different grating arrangements when the EPE structure 102 receives the first group of incoupling beams diffracted by the incoupling structure 101 having the one-dimensional diffraction grating.

[0098] The k-space representation 1102 corresponds to an EPE structure 102 having a lattice structure with a lattice vector length ratio of 0.96 and an angle between the lattice vectors of 122°.

[0099] The k-space representation 1103 corresponds to an EPE structure 102 having a lattice structure with a lattice vector length ratio of 0.70 and an angle between the lattice vectors of 110°.

[0100] The k-space representation 1104 corresponds to an EPE structure 102 having a lattice structure with a lattice vector length ratio of 0.82 and an angle between the lattice vectors of 127°.

[0101] The k-space representation 1105 corresponds to an EPE structure 102 having a lattice structure with a lattice vector length ratio of 0.62 and an angle between the lattice vectors of 108°.

[0102] FIG. 12 shows a schematic diagram of simulation results according to further embodiments.

[0103] In the embodiment of FIG. 12, each column corresponds to the lattice structure shown at the bottom. All of the lattice elements shown form the lattice structure of the EPE structure 102, while the lattice points of the black circles form the lattice structure of the incoupling structure 101. The fundamental vectors of these lattice structures are IC =2aEPE -b EPE , b IC =a EPE +b EPE The top of each row illustrates the k-space representation of a respective incoupling structure 101, while the center of each row illustrates the k-space representation of an EPE structure 102.

[0104] In the simulation results shown in FIGS. 10, 11, and 12, the simulation results are shown for only one wavelength.

[0105] Any ranges or device values ​​described herein may be expanded or modified without losing the effect sought, and any embodiment may be combined with another embodiment unless expressly prohibited.

[0106] Although the subject matter of the present invention has been described in language specific to structural features and / or acts, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example implementations of the claims, and other equivalent features and acts are intended to be within the scope of the claims.

[0107] It will be understood that the benefits and advantages discussed above may relate to one embodiment or may relate to several embodiments. The embodiments are not limited to those that solve any or all of the problems discussed above or those that have any or all of the benefits or advantages discussed above. Additionally, it will be further understood that a reference to "an" item may refer to one or more of that item.

[0108] Aspects of any embodiment described above may be combined with aspects of any other embodiment described above to form further embodiments without losing the intended effect.

[0109] As used herein, the term "comprising" means including the specified methods, sections or elements, but such sections or elements do not constitute an exclusive list and the methods or apparatus may include additional sections or elements.

[0110] It will be understood that the above description is provided by way of example only, and that various modifications may be made by those skilled in the art. The above specification, examples and data fully describe the structure and use of the exemplary embodiments. Although various embodiments have been described with a certain degree of detail, or with reference to one or more specific embodiments, those skilled in the art may make numerous modifications to the disclosed embodiments without departing from the spirit or scope of the present disclosure.

Claims

1. a waveguide (104), an incoupling structure (101) configured to couple input beams (901) into said waveguide (104) as first incoupling beams (110) associated with a first incoupling k-vector group (204_1) present in a first region (205_1) of k-space in an annular waveguide propagation region (201) associated with said waveguide (104); an exit pupil extension structure (102) comprising a diffraction grating and configured to receive the first incoupling beams (110) and diffract the first incoupling beams (110) in a first plurality of directions (206) in k-space to form three guided beams associated with three k-vectors (204_1, 204_2, 204_3) present in a first set of three regions (205_1, 205_2, 205_3) in the annular guided propagation region (201), including the first region (205_1); an outcoupling structure (103) configured to receive from the exit pupil extension structure (102) a first set of diffracted beams (111) associated with a set of diffracted k-vectors present in at least one of the first set of three regions (205_1, 205_2, 205_3) and to outcouple the first set of diffracted beams (111) from the waveguide (104) as output beams (902); A display component (100) comprising: the incoupling structure (101) is further configured to couple the input beam group (901) into the waveguide plate (104) as a second incoupling beam group corresponding to a second incoupling k-vector group (304_1) existing in a second region (305_1) of k-space different from the first region (205_1) in the annular waveguide propagation region (201) associated with the waveguide plate (104); the exit pupil extension structure (102) is further configured to receive the second incoupling beam group and diffract the second incoupling beam group into a second plurality of directions (306) in k-space to form three guided beam groups associated with three k-vector groups (304_1, 304_2, 304_2) present in a second three region group (305_1, 305_2, 305_3) different from the first three region group (305_1, 305_2, 305_3) in the annular waveguide propagation region (201) including the second region (305_1); The outcoupling structure (103) is further configured to receive from the exit pupil extension structure (102) a second group of diffracted beams associated with diffracted k-vectors present in at least one of the second three groups of regions (205_1, 205_2, 205_3) and to outcouple the second group of diffracted beams from the waveguide (104) as the output beams (902).

2. 2. The display component (100) of claim 1, wherein the incoupling structure (101) comprises an incoupling diffraction grating for coupling the input beam group (901) into the waveguide plate, and / or the outcoupling structure (103) comprises an outcoupling diffraction grating for outcoupling the first diffracted beam group and / or the second diffracted beam group from the waveguide plate.

3. The incoupling structure has a fundamental lattice vector a ＩＣ (707) and b ＩＣ (708), the exit pupil extension structure (102) comprising a spatially periodic diffraction grating having a primitive grating vector a ＥＰＥ (705) and b ＥＰＥ (706), ＩＣ (707), b ＩＣ (708) Angle between and a ＥＰＥ (705), b ＥＰＥ (706) The angle between them is less than 90 degrees, ＩＣ = 2a ＥＰＥ -b ＥＰＥ and b ＩＣ = a ＥＰＥ +b ＥＰＥ 3. The display component (100) of claim 1 or 2,

4. The outcoupling structure (103) is a fundamental lattice vector a ＩＣ (707) and b ＩＣ The display component (100) of claim 3 comprising a spatially periodic hexagonal diffraction grating having (708).

5. 4. A display component as claimed in claim 1, wherein the exit pupil expansion structure (102) is located on a first surface of the waveguide (104) and the outcoupling structure (103) is located on a second surface of the waveguide (104), the outcoupling structure (103) comprising a one-dimensional diffraction grating.

6. 6. A display component (100) according to claim 1, wherein the hexagonal diffraction grating of the exit pupil extension structure (102) is located on a first surface of the waveguide (104) and the exit pupil extension structure (102) further comprises a one-dimensional diffraction grating on a second surface of the waveguide (104) configured to generate further diffraction between the first three groups of regions (205_1, 205_2, 205_3) and / or between the second three groups of regions (305_1, 305_2, 305_3).

7. 7. A display component (100) according to any one of claims 1 to 6, wherein the exit pupil extension structure (102) is configured to diffract the first incoupling beam group (110) in zeroth and first diffraction orders to form the three guided beam groups corresponding to the three k-vector groups (204_1, 204_2, 204_3) present in the first three region groups (205_1, 205_2, 205_3).

8. 8. A display component (100) according to any one of claims 1 to 7, wherein the exit pupil extension structure (102) is configured only to diffract the first incoupling beam group in zeroth and first diffraction orders to form the three guided beam groups corresponding to the three k-vector groups (204_1, 204_2, 204_3) present in the first three region groups (205_1, 205_2, 205_3).

9. A display component (100) as described in any one of claims 1 to 8, wherein the waveguiding propagation region (201) surrounds the coupling region (202) and the first group of three regions forms a triangle, an equilateral triangle or an isosceles triangle that at least partially overlaps with the coupling region (202).

10. A display device comprising a display component according to any one of claims 1 to 9.

11. 11. The display device of claim 10, comprising a scanner-based light engine, e.g. a laser scanning light engine, for directing the input beams (901) to the in-coupling structure.

12. 12. A display device according to claim 11 or 11, implemented as a see-through display device.

13. 13. A display device according to any of claims 10 to 12, implemented as a head mounted display device.

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