Display component

Abstract

According to an embodiment, a display component (100) comprises a waveguide (101); a first in-coupling structure (102) configured to couple a first set of input beams (111) comprising a first wavelength range into the wave-guide (101) as a first set of in-coupled beams (112); a second in-coupling structure (103) configured to couple a second set of input beams (121) comprising a second wavelength range into the waveguide (101) as a second set of in-coupled beams (122); a first exit pupil expansion structure (104) configured to receive the second set of in-coupled beams (122) and to diffract the second set of in-coupled beams (122) to form a first set of diffracted beams (123); and an out-coupling structure (105) configured to receive the first set of in-coupled beams (112) and the first set of diffracted beams (123), and to out-couple the first set of in-coupled beams (112) and the first set of diffracted beams (123) from the waveguide (101) as a set of output beams (131).

Description

DISPLAY COMPONENTTECHNICAL FIELD

[0001] The present disclosure relates to the field of optics , and more particularly to a display component and a display device .BACKGROUND

[0002] In augmented reality (AR) applications , such as AR glasses , a waveguide with appropriately designed in-coupling and out-coupling structures can be used to create multiple replicas of an exit pupil of a microproj ector in front of a user' s eye . Designing such structures for multiple different colours of light can be challenging .SUMMARY

[0003] This summary is provided to introduce a selection of concepts in a s implif ied form that are further described below in the detailed description . This summary is not intended to identify key features or essential features of the claimed subj ect matter, nor is it intended to be used to limit the scope of the claimed subj ect matter .

[0004] It is an obj ect to provide a display component and a display device . The foregoing and other obj ects are achieved by the features of the independent claims .Further implementation forms are apparent from the dependent claims , the description and the figures .

[0005] According to a first aspect , a display component comprises : a waveguide ; a first in-coupling structure configured to couple a first set of input beams comprising a first wavelength range into the waveguide as a first set of in-coupled beams associated with a first set of in-coupled k vectors lying in a first domain in k-space in an annular guided propagation domain as sociated with the waveguide ; a second in-coupling structure configured to couple a second set of input beams comprising a second wavelength range into the waveguide as a second set of in-coupled beams associated with a second set of in-coupled k vectors lying in a second domain in k-space in the annular guided propagation domain associated with the waveguide ; a f irst exit pupil expansion structure configured to receive the second set of in-coupled beams and to diffract the second set of in-coupled beams to form a first set of diffracted beams associated with a first set of diffracted k vectors lying in a third domain in the annular guided propagation domain ; and an out-coupling structure configured to receive the first set of in-coupled beams and the first set of diffracted beams , and to out-couple the first set of in-coupled beams and the first set of diffracted beams from the waveguide as a set of output beams .

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

[0007] Many of the attendant features wil l be more readily appreciated as they become better understood by reference to the following detailed description considered in connection with the accompanying drawings .DESCRIPTION OF THE DRAWINGS

[0008] In the following, example embodiments are described in more detail with reference to the attached figures and drawings , in which :

[0009] Fig . 1 illustrates a schematic representation of a display component according to an embodiment ;

[0010] Fig . 2 illustrates a k-space representation of beams diffracted by the display component according to an embodiment ;

[0011] Fig . 3 illustrates a schematic representation of a display component according to another embodiment ;

[0012] Fig . 4 illustrates a k-space representation of beams diffracted by the display component according to an embodiment ;

[0013] Fig . 5 illustrates a schematic representation of a display component according to another embodiment ; and

[0014] Fig . 6 illustrates a schematic representation of display device according to an embodiment .

[0015] In the following, identical reference signs refer to similar or at least functionally equivalent features .DETAILED DESCRIPTION

[0016] In the following description, reference is made to the accompanying drawings , which form part of the disclosure , and in which are shown, by way of illustration, specific aspects in which the present disclosure may be placed . It is understood that other aspects may be utilised, and structural or logical changes may be made without departing from the scope of the present disclosure . The following detailed description, therefore , is not to be taken in a limiting sense , as the scope of the present disclosure is defined be the appended claims .

[0017] For instance , it is understood that a disclosure in connection with a described method may also hold true for a corresponding device or system configured to perform the method and vice versa . For example , if a specific method step is described, a corresponding device may include a unit to perform the described method step, even if such unit is not explicitly described or il lustrated in the f igures . On the other hand, for example , if a specific apparatus is described based on functional units , a corresponding method may include a step performing the described functionality, even if such step is not explicitly described or illustrated in the figures . Further, it is understood that the featuresof the various example aspects described herein may be combined with each other, unless specifically noted otherwise .

[0018] Fig . 1 illustrates a schematic representation of a display component according to an embodiment .

[0019] According to an embodiment , a display component 100 comprises a waveguide 101 .

[0020] The waveguide 101 may comprise , for example , a substantially planar waveguide . Alternatively or additionally, the waveguide 101 may also comprise curved sections . For example, the waveguide 101 may correspond to a lens or a layer of a lens of augmented reality (AR) glasses .

[0021] The display component 100 may further comprise a first in-coupling ( IC) structure 102 configured to couple a first set of input beams 111 comprising a first wavelength range into the waveguide 101 as a f irst set of in-coupled beams 112 as sociated with a first set of in-coupled k vectors lying in a first domain in k-space in an annular guided propagation domain associated with the waveguide 101 .

[0022] The first set of input beams 111 may be generated by, for example , a scanner-based optical engine . The first set of input beams 111 may represent an image generated by, for example , such an optical engine . Thus , the first set of input beams 111 may also be referred to as , for example , first image-bearing light rays / beams , first image-carrying light rays / beams , and / or similar .

[0023] The display component 100 may further comprise a second in-coupling structure 103 configured to couple a second set of input beams 121 comprising a second wavelength range into the waveguide 101 as a second set of in-coupled beams 122 associated with a second set of in-coupled k vectors lying in a second domain in k-space in the annular guided propagation domain associated with the waveguide 101 .

[0024] The second set of input beams 121 may be generated by, for example , a scanner-based optical engine . The second set of input beams 121 may represent an image generated by, for example , such an optical engine . Thus , the second set of input beams 121 may also be referred to as , for example , second image-bearing light rays / beams , second image-carrying light rays / beams , and / or similar .

[0025] The first and second set of input beams 111 , 121 may correspond to , for example , different colour channels of an image generated by, for example , an optical engine .

[0026] By separating different wavelength ranges into different input beams and using separate IC structures for different wavelength ranges , the corresponding components can be designed for the specific wavelength range .

[0027] Herein, any in-coupling structure may comprise , for example , a diffraction grating on a surface of the waveguide 101 . Any in-coupling structure may cou-pie a corresponding set of input beams into the waveguide 101 via diffraction . Alternatively, any in-coupling structure may be implemented in some other way, such as those disclosed herein .

[0028] The first wavelength range and the second wavelength range may be at least partially non-overlapping or totally non-overlapping .

[0029] In the embodiment of Fig . 1 , the first / second set of input beams 111 , 121 may propagate in a plurality of directions that are not in the plane of the waveguide 101 .

[0030] The display component 100 may further comprise a first exit pupil expansion (EPE ) structure 104 configured to receive the second set of in-coupled beams 122 and to di ffract the second set of in-coupled beams 122 to form a first set of diffracted beams 123 associated with a first set of diffracted k vectors lying in a third domain in the annular guided propagation domain .

[0031] It should be appreciated that the first diffracted set of beams 123 il lustrated in the embodiment of Fig . 1 are only illustrative . In practical embodiments , the first EPE structure 104 can diffract the second set of in-coupled beams 122 in a plurality of directions in a much more complex manner and the first set of diffracted beams 123 can interact with the first EPE structure 104 a plurality of times .

[0032] For example , as the second set of in-coupled beams 122 propagates in the area of the first EPE structure 104 , the second set of in-coupled beams 122 caninteract with the first EPE structure 104 each time the the second set of in-coupled beams 122 hits the side of the waveguide 101 on which the first EPE structure 104 is located . In the interaction, a part of the set of incoupled beams 122 can diffract from the first EPE structure 104 as the first set of diffract beams 123 and a part can continue to propagate in the original direction . Thus , the first EPE structure 104 can perform exit pupil expansion . In some embodiments , the first EPE structure 104 can perform exit pupil expansion in a plurality of directions .

[0033] The display component 100 may further comprise an out-coupling (OC) structure 105 configured to receive the first set of in-coupled beams 112 and the first set of diffracted beams 123 , and to out-couple the first set of in-coupled beams 112 and the first set of diffracted beams 123 from the waveguide 101 as a set of output beams 131 .

[0034] In the embodiment of Fig . 1 , the set of output beams 131 may propagate in a plurality of directions that are not in the plane of the waveguide 101 .

[0035] The set of output beams 131 may further comprise light from other sources , such as those disclosed herein .

[0036] In some embodiments , the OC structure 105 may be configured to diffract the first set of in-coupled beams 112 and / or the f irst set of dif fracted beams 123 before out-coupling the first set of in-coupled beams 112 and the first set of diffracted beams 123 from thewaveguide 101 . For example , the OC structure 105 may be configured to perform exit pupil expansion on the first set of in-coupled beams 112 and / or the first set of diffracted beams 123 before out-coupling the first set of in-coupled beams 112 and the first set of diffracted beams 123 from the waveguide 101 .

[0037] For example , as the first set of in-coupled beams 112 propagates in the area of the OC structure 105 , the second set of in-coupled beams 112 can interact with the OC structure 105 each time the the second set of in-coupled beams 112 hits the side of the waveguide 101 on which the OC structure 105 is located . In the interaction, a part of the set of in-coupled beams 122 can diffract from the OC structure 105 and thus be out- coupled from the waveguide 101 in the set of output beams 131 and a part can continue to propagate in the original direction . Thus , the OC structure 105 can perform exit pupi l expansion . In some embodiments , the OC structure 105 can perform exit pupil expansion in a plurality of directions . In some embodiments , the OC structure 105 can perform exit pupil expansion on the first set of diffracted beams 123 and / or any other beams .

[0038] The OC structure 105 may comprise , for example , a diffraction grating on a surface of the waveguide 101 . The OC structure 105 may out-couple the first set of incoupled beams 112 and the first set of diffracted beams 123 from the waveguide 101 via diffraction .

[0039] The set of output beams 131 may represent , for example, an expanded version of the image formed by the first / second set of input beams 111 , 121 .

[0040] The first / second set of in-coupled beams 112 , 122 and the first set of diffracted beams 123 can be guided inside the waveguide 101 via total internal reflection ( TIR) .

[0041] The first set of in-coupled beams 112 and / or the first set of diffracted beams 123 may interact with the EPE structure 104 and / or with the OC structure 105 a plurality of times before being out-coupled from the waveguide 101 as the set of output beams 131 .

[0042] Herein, a beam may also be referred to as a ray, a light beam, a light ray, or similar .

[0043] According to an embodiment , the first IC structure 102 and / or the second IC structure 103 comprises a one-dimensional or a two-dimensional in-coupling diffraction grating .

[0044] According to an embodiment , and the OC structure 105 comprises a one-dimens ional or a two-dimensional out-coupling diffraction grating .

[0045] According to an embodiment , the first EPE structure 104 comprises a one-dimensional or a two-dimensional diffraction grating .

[0046] Herein, a diffraction grating may also be referred to as a surface-relief grating, a grating, a diffractive grating, or similar .

[0047] According to an embodiment , the first IC structure 102 and / or the second IC structure 103 is conf igured to diffract the first / second set of input beams 111 , 121 via zeroth order and first order diffractions .

[0048] According to an embodiment , the OC structure 105 is configured to out-couple the first set of incoupled beams 112 and the first set of diffracted beams 123 via first order diffractions .

[0049] It should be understood that the geometry of the display component 100 illustrated in the embodiment of Fig . 1 is only exemplary and the display component 100 may be implemented in various other ways .

[0050] According to an embodiment , the first in-coupling structure 102 comprises an in-coupling diffraction grating, a pri sm, and / or a chamfered edge of the waveguide 101 .

[0051] According to an embodiment , the out-coupling structure 105 is further configured perform exit pupil expansion by diffracting the first set of in-coupled beams 112 to form a third set of diffracted beams and to out-couple the third set of di ffracted beams in the set of out-coupled beams 131 .

[0052] According to an embodiment , the out-coupling structure 105 comprises an out-coupling diffraction grating .

[0053] According to an embodiment , the first exit pupil expansion structure 104 is configured diffract the second set of in-coupled beams 122 via zeroth order andfirst order di ffractions to form the f irst set of dif fracted beams 123 .

[0054] In any embodiments disclosed herein, any structure , such as the first / second IC structure 102 , 103 , the EPE structure 104 and / or the OC structure 105 may be positioned on any side of the waveguide 101 .

[0055] In any embodiment disclosed herein, the first / second IC structure 102 , 103 and / or the OC structure 105 may comprise reflective or transmissive diffraction gratings .

[0056] Fig . 2 illustrates a k-space representation of beams diffracted by the display component according to an embodiment .

[0057] The first IC structure 102 can couple the first set of input beams 111 compris ing the first wavelength range into the waveguide 101 as the first set of incoupled beams 112 associated with a first set of incoupled k vectors 203 lying in a first domain 204 in k- space in an annular guided propagation domain 210 associated with the waveguide .

[0058] The second IC structure 103 can couple the second set of input beams 121 comprising the second wavelength range into the waveguide 101 as the second set of in-coupled beams 122 associated with a second set of in-coupled k vectors 201 lying in a second domain 202 in k-space in the annular guided propagation domain 210 associated with the waveguide 101 .

[0059] The second domain 202 can be disj oint from the first domain 204 .

[0060] The first EPE structure 104 can receive the second set of in-coupled beams 122 and diffract the second set of in-coupled beams 122 to form the first set of diffracted beams 123 associated with a first set of diffracted k vectors 205 lying in a third domain 206 in the annular guided propagation domain 210 .

[0061] The third domain 206 can be di sj oint from the first domain 204 . The third domain 206 can be di sj oint from the second domain 202 .

[0062] Herein, an annular guided propagation domain 210 may refer to a part of the k-space in which beams are guided inside the waveguide 101 . An example of an annular guided propagation domain 210 is illustrated in the embodiment of Fig . 2 .

[0063] Each k-vector in k-space can represent a propagation direction of a beam inside the waveguide 101 . The magnitude of each k-vector corresponds to a wavenumber k . A k-vector can be expressed as k = nv, where n is the refractive index of the medium of the waveguide 101 and v is a unit vector pointing towards the propagation direction of the k-vector . k may also be referred to as a normali zed k-vector .

[0064] The waveguide 101 can guide beams having certain k-vectors via total internal reflection ( TIR) . A coupling domain 220 corresponds to k-vectors that do not have sufficient x and / or y components to be guided inside the waveguide 101 via TIR . Here , the x and y axes are in the plane of the waveguide 101 while the z axis is along a thickness direction of the waveguide 101 . Forsuch beams, the angle between the beam and the surface (s) of the waveguide 101 is not sufficient to cause TIR as governed by Snell's law. K-vectors inside the annular guided propagation domain 210 have sufficient x and / or y components to be guided inside the waveguide 101 via TIR. K-vectors at the outer circumference of the annular guided propagation domain 210 correspond to beams propagating along the plane of the waveguide 101, i.e. such beams do not have any z component. Radius of the coupling domain 220 may be 1 and radius of the annular guided propagation domain 210 may be .

[0065] According to an embodiment, the guided propagation domain 210 surrounds the coupling domain 220.

[0066] The first / second set of input beams 111, 121 can be associated with corresponding k-vectors 207 in the coupling domain 220. The first / second IC structure 102, 103 can couple the first / second set of input beams 111, 121 into the waveguide 101 as the first / second set of in-coupled beams 112, 122. This corresponds to shifting the k vectors into the annular guided propagation domain 210.

[0067] For example, in the embodiment of Fig. 2, k- vectors 207, corresponding to the first / second set of input beams 111, 121, are located in the coupling domain 220 of the k-space. The first / second IC structure 102, 103 can couple the first / second set of input beams 111, 121 into the waveguide 101 as the first / second set of in-coupled beams 112, 122 associated with the first / second set of in-coupled k-vectors 201, 203.

[0068] The first / second IC structure 102 , 103 may comprise , for example , diffraction gratings that can couple the first / second set of input beams 111 , 121 into the waveguide 101 . As can be seen in the embodiment of Fig . 2 , since the first / second set of in-coupled k-vectors 201 , 203 is inside the annular guided propagation domain 210 , the corresponding sets of in-coupled beams 112 , 122 are guided inside the waveguide 101 via TIR .

[0069] The different k-vectors in the first / second set of in-coupled k-vectors 201 , 203 , illustrated by the rectangles in the embodiment of Fig . 2 , may correspond to , for example , different parts of an image represented by the first / second set of input beams 111 , 121 .

[0070] Herein, a transition in k-space may correspond to an interaction of a set of beams with a diffraction grating . Such an interaction can cause the set of beams to propagate into a different direction or directions than before the interaction . The change in propagation direction can be observed as a translation in k-space along a transition .

[0071] For example , in the embodiment of Fig . 2 , transition 232 can correspond to the in-coupling of the first set of input beams 111 by the first IC structure 102 . Transition 231 can correspond to the in-coupling of the second set of input beams 121 by the second IC structure 103 . Transition 233 can correspond to the diffraction of the second set of in-coupled beams 122 by the first EPE structure 104 . Transition 234 can correspond to the out-coupling of the first set of in-coupledbeams 112 by the OC structure 105 . Transition 235 can correspond to out-coupling of the first set of diffracted beams 123 by the OC structure 105 .

[0072] In some embodiments , the OC structure 105 may be configured to diffract the first set of in-coupled beams 112 and / or the first set of di ffracted beams 123 before out-coupling the first set of in-coupled beams 112 and the first set of diffracted beams 123 from the waveguide 101 . For example, the OC structure 105 may be configured to perform exit pupil expansion on the first set of in-coupled beams 112 and / or the first set of diffracted beams 123 before out-coupling the first set of in-coupled beams 112 and the first set of diffracted beams 123 from the waveguide 101 . In terms of a k space representation, this can be illustrated as , instead of the single transitions 234 , 235 , the OC structure 105 can first perform a transition in the annular guided propagation domain 210 and then perform a transition from the annular guided propagation domain 210 to the coupling domain 220 .

[0073] According to an embodiment , the first domain 202 and / or the second domain 204 is located on an outer circumference of the annular guided propagation domain 210 .

[0074] The outer circumference of the annular guided propagation domain 210 may refer to an area of the annular guided propagation domain 210 close to the outer edge of the annular guided propagation domain 210 . Forexample , outer circumference of the annular guided propagation domain 210 may refer to an area of the annular guided propagation domain 210 within a radius of 0.7n — n, 0.8n - n, or 0.9n - n, where n is the radius of the annular guided propagation domain 210 as discussed above .

[0075] In some embodiments , the outer circumference of the annular guided propagation domain 210 may be an area of the guided propagation domain 210 that comprises and / or consi sts of points that are closer to the outer edge of the guided propagation domain 210 than the inner edge of the guided propagation domain 210 . In some embodiments , the outer circumference of the annular guided propagation domain 210 may be an area of the guided propagation domain 210 that is on an outer hal f of the guided propagation domain 210 .

[0076] When the first domain 202 and / or the second domain 204 are located on an outer circumference of the annular guided propagation domain 210 , the first / second set of in-coupled beams 112 , 122 have a large k vector component in the xy plane . Thus , the in-coupled beams travel a large distance between each TIR interaction with the waveguide 101 . Therefore, the number of interactions between the in-coupled beams 112 , 122 and the IC structures 102 , 103 can be reduced and unwanted out- coupling can thus be reduced .

[0077] Since the first / second wavelength ranges are separated into different input beams the display component 100 comprises separate IC structures for differentwavelength ranges , the first domain 202 and / or the second domain 204 can be located closer to the radius of the annular guided propagation domain 210 . For example , if the f irst and second wavelength ranges were in-coupled using one IC structure , one wavelength range could get diffracted outside the annular guided propagation domain 210 when the other one is diffracted close to the radius of the annular guided propagation domain 210 .

[0078] The first set of in-coupled beams 112 and / or the first set of diffracted beams 123 do not always out- couple when interacting with the OC structure 105 . For example , the OC structure 105 may perform exit pupil expansion in addition to out-coupling the f irst set of in-coupled beams 112 and / or the first set of diffracted beams 123 .

[0079] Although in some embodiments disclosed herein the k-vectors 207 corresponding to the first / second set of input beams 111 , 121 are located at the k-space origin, this may not be the case for all embodiments . For example , if the propagation direction of the first / second set of input beams 111 , 121 is not perpendicular to the waveguide 101 , the k-vectors 207 corresponding to the first / second set of input beams 111 , 121 may be located in some other part of the coupling domain 220 .

[0080] According to an embodiment , the out-coupling structure 105 comprises an out-coupling grating with a plurality of grating vectors , the second in-coupling structure 103 comprises at least a first grating vector,the second in-coupling structure 103 is configured to couple the second set of input beams 121 into the waveguide 101 according to the first grating vector, the first exit pupil expansion structure 104 comprises at least a second grating vector, the first exit pupil expansion structure 104 is configured to diffract the second set of in-coupled beams 122 according to the second grating vector, and a sum of the first grating vector, the second grating vector , and a linear combination of the plural ity of grating vectors of the out- coupling grating is substantially zero .

[0081] According to an embodiment , the out-coupling structure 105 comprises an out-coupling grating with a plurality of grating vectors , the first in-coupling structure 102 comprises at least a fifth grating vector, the first in-coupling structure 102 is configured to couple the first set of input beams 111 into the waveguide 101 according to the fifth grating vector, and a sum of the fifth grating vector and a linear combination of the plurality of grating vectors of the out-coupling grating is substantially zero .

[0082] Grating vectors may represent the periodicity and orientation of the corresponding diffraction gratings . For example , a diffraction grating can comprise ridges / grooves and the grating vectors can correspond to the spatial periodicity and orientation of these ridges / grooves . The structure of these ridges / grooves define the diffraction caused by the diffraction grat-ing . Length of a grating vector may be inversely proportional to the spatial period of the corresponding diffraction grating in the direction of the grating vector . Thus , the ridges / grooves of the diffraction grating may run along a direction perpendicular to the direction of the grating vector . A two-dimensional diffraction grating can comprise a plurality of grating vectors .

[0083] For example , in the embodiment of Fig . 2 , transition 231 can correspond to the first grating vector of the second IC structure 103 , transition 233 can correspond to the second grating vector of the first EPE structure 104 , and transition 235 can correspond to a linear combination of the plurality of grating vectors of the OC structure 105 . Thus , in the embodiment of Fig . 2 , the sum of the first grating vector, the second grating vector, and a linear combination of the plurality of grating vectors of the out-coupling grating is substantially zero .

[0084] It should be appreciated that the grating vector for a specific diffraction grating can be chosen in various ways . For example , for a one-dimensional grating, there may be two possible grating vectors pointing in the opposite directions that describe the same onedimensional grating .

[0085] It should be understood that the manufacturing of a diffraction grating may be limited by the manufacturing method used . The sum of the first grating vector, the second grating vector, and the linear combination of the plurality of grating vectors of the out-couplinggrating being substantially zero may mean that the sum is substantially zero within the tolerances / limitations of the used manufacturing method .

[0086] Fig . 3 illustrates a schematic representation of a display component according to another embodiment .

[0087] According to an embodiment , the display component 100 further comprise a third in-coupling structure 301 configured to couple a third set of input beams 311 comprising a third wavelength range into the waveguide 101 as a third set of in-coupled beams 312 associated with a third set of in-coupled k-vectors lying in a fourth domain in k-space in the annular guided propagation domain associated with the waveguide 101 .

[0088] The third set of input beams 311 may be generated by, for example , a scanner-based optical engine . The third set of input beams 311 may represent an image generated by, for example , such an optical engine . Thus , the third set of input beams 311 may also be referred to as , for example , third image-bearing light rays / beams , third image-carrying light rays / beams , and / or similar .

[0089] The third wavelength range and the second wavelength range may be at least partially non-overlapping or totally non-overlapping .

[0090] The first wavelength range and the third wavelength range may be at least partially non-overlapping or totally non-overlapping .

[0091] The first , second, and third set of input beams 111 , 121 , 311 may correspond to , for example, differentcolour channels of an image generated by, for example , an optical engine .

[0092] The display component 100 may further comprise a second exit pupil expansion structure 302 configured to receive the third set of in-coupled beams 312 and to di ffract the third set of in-coupled beams 312 to form a second set of dif fracted beams 313 associated with a second set of diffracted k-vectors lying in a fifth domain in the annular guided propagation domain . The out-coupling structure 105 may be further configured to receive the second set of diffracted beams 313 and to out-couple the second set of dif fracted beams 313 from the waveguide 101 in the set of output beams 131 .

[0093] Any disclosure herein in relation to the first / second IC structure 102 , 103 , the first / second set of input beams 111 , 121 , and / or the first / second set of in-coupled beams 112 , 122 may also apply to the third IC structure 301 , the third set of input beams 311 and / or the third set of in-coupled beams 312 .

[0094] Any disclosure herein in relation to the first EPE structure 104 , the second set of in-coupled beams 122 , and / or the first set of diffracted beams 123 may also apply to the second EPE structure 302 , the third set of in-coupled beams 312 , and / or the second set of diffracted beams 313 .

[0095] According to an embodiment , the second EPE structure 302 comprises a one-dimensional or a two-dimensional diffraction grating .

[0096] Fig . 4 illustrates a k-space representation of beams diffracted by the display component according to an embodiment .

[0097] The third IC structure 301 can couple the third set of input beams 311 into the waveguide 101 as the third set of in-coupled beams 312 associated with a third set of in-coupled k-vectors 401 lying in a fourth domain 402 in k-space in the annular guided propagation domain 210 associated with the waveguide 101 .

[0098] The fourth domain 402 can be disj oint from the first domain 204 . The fourth domain 402 can be disj oint from the second domain 202 . The fourth domain 402 can be disj oint from the third domain 206 .

[0099] The second EPE structure 302 can receive the third set of in-coupled beams 312 and diffract the third set of in-coupled beams 312 to form a second set of diffracted beams 313 associated with a second set of diffracted k-vectors 403 lying in a fifth domain 404 in the annular guided propagation domain 210 .

[0100] The fifth domain 404 can be di sj oint from the first domain 204 . The f ifth domain 404 can be di sj oint from the second domain 202 . The fifth domain 404 can be disj oint from the third domain 206 . The fifth domain 404 can be disj oint from the fourth domain 402 .

[0101] In the embodiment of Fig . 4 , transition 411 can correspond to the in-coupling of the third set of input beams 311 by the third IC structure 301 . Transition 412 can correspond to the diffraction of the third set ofin-coupled beams by the second EPE structure 302 . Transition 413 can correspond to out-coupling of the second set of diffracted beams 313 by the OC structure 105 .

[0102] According to an embodiment , the OC structure 105 comprises an out-coupling grating with a plurality of grating vectors , the third IC structure 301 comprises at least a third grating vector, the third IC structure301 is configured to couple the third set of input beams 311 into the waveguide 101 according to the third grating vector, the second EPE structure 302 comprises at least a fourth grating vector, the second EPE structure302 is configured to di ffract the third set of in-coupled beams 312 according to the fourth grating vector, and a sum of the third grating vector, the fourth grating vector, and a linear combination of the plurality of grating vectors of the out-coupl ing grating is substantially zero .

[0103] For example , in the embodiment of Fig . 4 , transition 411 can correspond to the third grating vector of the third IC structure 301 , transition 412 can correspond to the fourth grating vector of the second EPE structure 302 , and transition 413 can correspond to a linear combination of the plurality of grating vectors of the OC structure 105 . Thus , in the embodiment of Fig . 4 , the sum of the third grating vector, the fourth grating vector, and a linear combination of the plurality of grating vectors out-coupling grating is substantially zero .

[0104] Fig . 5 illustrates a schematic representation of a display component according to another embodiment .

[0105] According to an embodiment , the display component 100 further comprises a third in-coupling structure 501 configured to couple a third set of input beams 511 comprising a third wavelength range into the waveguide 101 as a third set of in-coupled beams 512 associated with a third set of in-coupled k-vectors lying in a fourth domain in k-space in the annular guided propagation domain associated with the waveguide 101 , wherein the out-coupling structure 105 is further configured to receive the third set of in-coupled beams 512 , and to out-couple the third set of in-coupled beams 512 from the waveguide in the set of output beams 131 .

[0106] The third set of input beams 511 may be generated by, for example , a scanner-based optical engine . The third set of input beams 511 may represent an image generated by, for example , such an optical engine . Thus , the third set of input beams 511 may also be referred to as , for example , third image-bearing light rays / beams , third image-carrying light rays / beams , and / or similar .

[0107] The third wavelength range and the second wavelength range may be at least partially non-overlapping or totally non-overlapping .

[0108] The first wavelength range and the third wavelength range may be at least partially non-overlapping or totally non-overlapping .

[0109] The first , second, and third set of input beams 111 , 121 , 511 may correspond to , for example, different colour channels of an image generated by, for example , an optical engine .

[0110] The coupling of the third set of input beams 511 into the waveguide 101 as the third set of incoupled beams 512 can be illustrated in k space similarly to the transition 232 in the embodiments of Fig . 2 and 4 . The out-coupling of the third set of in-coupled beams 512 from the waveguide 101 can be i llustrated in k space similarly to the transition 234 in the embodi ments of Fig . 2 and 4 . The fourth domain may comprise the first domain 204 .[01 1 1 ] According to an embodiment , the out-coupling structure 105 comprises an out-coupling grating with a plurality of grating vectors , the third in-coupling structure 501 comprises at least a sixth grating vector, the third in-coupling structure 501 is configured to couple the third set of input beams 511 into the waveguide 101 according to the sixth grating vector, and a sum of the sixth grating vector and a linear combination of the plurality of grating vectors of the out-coupling grating is substantially zero .

[0112] Fig . 6 illustrates a schematic representation of display device according to an embodiment .[01 1 3] According to an embodiment , a display device 600 comprises the display component 100 .

[0114] The display device 600 may comprise a scannerbased optical engine and / or a laser-scanning opticalengine 601 for directing the first set of input beams at least to the first in-coupling structure . Other types of optical engines may also be used .[01 1 5] A laser-scanning optical engine may comprise , for example , a laser beam scanning (LBS ) optical engine .

[0116] In some embodiments , the optical engine may comprise a liquid crystal on silicon (LOOS ) based optical engine , a digital light processing ( DLP) based optical engine , and / or a microLED based optical engine .[01 1 7] A laser-scanning optical engine may be needed, for example , in embodiments where the in-coupling structure 102 is implemented using a chamfered edge of the waveguide 101 .

[0118] In some embodiments , the scanner-based optical engine and / or the laser-scanning optical engine 601 may be configured to provide the first set of input beams at least to the first IC structure , the second set of input beams at least to the second IC structure , and / or the third set of input beams at least to the third IC structure . In other embodiments , the display device 600 may comprise a plurality of optical engines , wherein each optical engine is configured to provide a corresponding set of input beams to a corresponding IC structure .

[0119] The display device 600 may be implemented as , for example , a see-through display device .

[0120] The display device 600 may be implemented as , for example , a head-mounted display device .

[0121] For example , in the embodiment of Fig . 6 , the display device 600 is implemented as smart glasses . The waveguide 101 can correspond to a lens or a layer of a lens of such smart glasses . Such smart glasses may be used to, for example , implement augmented reality (AR) , virtual reality (VR) , and / or extended reality (XR) functionality .

[0122] In the embodiment of Fig . 6 , a set of input beams 602 may be generated by, for example , an optical engine 601 , such as a scanner-based optical engine . The set of input beams 602 may comprise any combination of the sets of input beams 111 , 121 , 311 , 511 . The set of input beams 602 may represent an image generated by, for example , the optical engine 601 . The display component 100 of the display device 600 can direct the set of output beams 131 representing the image generated by the optical engine 601 into the eye of a user .

[0123] Any range or device value given herein may be extended or altered without losing the effect sought . Also any embodiment may be combined with another embodiment unless explicitly disallowed .

[0124] Although the subj ect matter has been described in language specific to structural features and / or acts , it is to be understood that the subj ect 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 disclosedas examples of implementing the claims and other equivalent features and acts are intended to be within the scope of the claims .

[0125] It will be understood that the benefits and advantages described 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 stated problems or those that have any or all of the stated benefits and advantages . It wil l further be understood that reference to ' an ' item may refer to one or more of those items .

[0126] Aspects of any of the embodiments described above may be combined with aspects of any of the other embodiments described to form further embodiments without losing the effect sought .

[0127] The term ' comprising ' is used herein to mean including the method, blocks or elements identified, but that such blocks or elements do not comprise an exclusive list and a method or apparatus may contain additional blocks or elements .

[0128] It will be understood that the above description is given by way of example only and that various modif ications may be made by those ski lled in the art . The above specification, examples and data provide a complete description of the structure and use of exemplary embodiments . Although various embodiments have been described above with a certain degree of particularity, or with reference to one or more individualembodiments , those skilled in the art could make numerous alterations to the disclosed embodiments without departing from the spirit or scope of this specification .

Claims

CLAIMS :

1. A display component (100) , comprising: a waveguide (101) ; a first in-coupling structure (102) configured to couple a first set of input beams (111) comprising a first wavelength range into the waveguide (101) as a first set of in-coupled beams (112) associated with a first set of in-coupled k-vectors (203) lying in a first domain (204) in k-space in an annular guided propagation domain (210) associated with the waveguide (101) ; a second in-coupling structure (103) configured to couple a second set of input beams (121) comprising a second wavelength range into the waveguide (101) as a second set of in-coupled beams (122) associated with a second set of in-coupled k-vectors (201) lying in a second domain (202) in k-space in the annular guided propagation domain (210) associated with the waveguide (101) ; a first exit pupil expansion structure (104) configured to receive the second set of in-coupled beams (122) and to diffract the second set of in-coupled beams (122) to form a first set of diffracted beams (123) associated with a first set of diffracted k-vectors (205) lying in a third domain (206) in the annular guided propagation domain (210) ; an out-coupling structure (105) configured to receive the first set of in-coupled beams (112) and the first set of diffracted beams (123) , and to out-couple the first set of in-coupled beams (112) and the firstset of diffracted beams (123) from the waveguide (101) as a set of output beams (131) ; and a third in-coupling structure (301) configured to couple a third set of input beams (311) comprising a third wavelength range into the waveguide (101) as a third set of in-coupled beams (312) associated with a third set of in-coupled k-vectors (401) lying in a fourth domain (402) in k-space in the annular guided propagation domain (210) associated with the waveguide (101) .

2. The display component (100) according to claim 1, further comprising: a second exit pupil expansion structure (302) configured to receive the third set of in-coupled beams (312) and to diffract the third set of in-coupled beams(312) to form a second set of diffracted beams (313) associated with a second set of diffracted k-vectors (403) lying in a fifth domain (404) in the annular guided propagation domain (210) ; wherein the out-coupling structure (105) is further configured to receive the second set of diffracted beams(313) and to out-couple the second set of diffracted beams (313) from the waveguide (101) in the set of output beams ( 131 ) .

3. The display component (100) according to claim 1, wherein the out-coupling structure is further configured to receive the third set of in-coupled beams,and to out-couple the third set of in-coupled beams from the waveguide in the set of output beams.

4. The display component (100) according to any preceding claim, wherein the out-coupling structure (105) comprises an out-coupling grating with a plurality of grating vectors, the second in-coupling structure (103) comprises at least a first grating vector, the second in-coupling structure is configured to couple the second set of input beams (121) into the waveguide (101) according to the first grating vector, the first exit pupil expansion structure (104) comprises at least a second grating vector, the first exit pupil expansion structure (104) is configured to diffract the second set of in-coupled beams (122) according to the second grating vector, and a sum of the first grating vector, the second grating vector, and a linear combination of the plurality of grating vectors of the out-coupling grating is substantially zero.

5. The display component (100) according to any preceding claim, wherein the first domain (204) and / or the second domain (202) is located on an outer circumference of the annular guided propagation domain (210) .

6. The display component (100) according to any preceding claim, wherein the first in-coupling structure (102) comprises an in-coupling diffraction grating, a prism, and / or a chamfered edge of the waveguide.

7. The display component (100) according to any preceding claim, wherein the out-coupling structure (105) is further configured perform exit pupil expansion by diffracting the first set of in-coupled beams (112) to form a third set of diffracted beams and to out- couple the third set of diffracted beams in the set of out-coupled beams (131) .

8. The display component (100) according to any preceding claim, wherein the out-coupling structure (105) comprises an out-coupling diffraction grating.

9. The display component (100) according to any of the preceding claim, wherein the first exit pupil expansion structure (104) is configured diffract the second set of in-coupled beams (122) via zeroth order and first order diffractions to form the first set of diffracted beams (123) .

10. A display device (600) comprising a display component (100) according to any preceding claim.

11. A display device (600) according to claim 10, comprising a scanner-based optical engine and / or a laser-scanning optical engine (601) , for directing the first set of input beams at least to the first in-coupling structure.

12. A display device (600) according to claim 10 or 11 implemented as a see-through display device .

13. A display device (600) according to any of claims 10 - 12 implemented as a head-mounted display device .

Images