Ar waveguide and ar device

Abstract

The application discloses an AR waveguide and an AR device, the AR waveguide comprises a first light waveguide including a first light waveguide body, a first entrance pupil region, a first turning region, a second turning region, a first exit pupil region and a second exit pupil region; the second light waveguide at least includes a second light waveguide body, a second entrance pupil region and a third exit pupil region; the projection of the second entrance pupil region to the surface where the first entrance pupil region is located at least partially overlaps with the first entrance pupil region; the projection of the third exit pupil region to the surface where the first turning region or the second turning region is located at least partially overlaps with the first turning region or the second turning region. Thus, by setting the second light waveguide to increase the image light beams coupled out by the second exit pupil region, the brightness of the side edge of the image presented by the image light beams is improved, and the phenomenon that the brightness of the edge region of the image is low is reduced, so that the display effect of the image is improved, and the user experience is improved.

Description

Technical Field

[0001] This application relates to the technical field of AR devices, and more specifically, to an AR waveguide and an AR device. Background Technology

[0002] Augmented Reality (AR) technology is widely used in various fields such as gaming, education, and healthcare. AR devices provide users with an immersive experience by combining virtual information with the real world. As one of the key hardware components of AR technology, AR glasses need to possess characteristics such as lightweight design, high resolution, a large field of view (FOV), high brightness, and low power consumption to meet users' needs for wearing comfort and experience. The optical display system in AR glasses typically employs waveguide display technology, with waveguide sheets as its core component. Waveguide sheets split, guide, and output the image beam displayed by the optomechanical system to achieve the transmission and display of virtual images.

[0003] In practical optical display systems, due to the long propagation path of light in the waveguide, the light gradually attenuates with multiple total internal reflections, resulting in gradual energy loss. Especially when the light propagates to the edge area of ​​the image, the light intensity is significantly lower than that in the center area, which causes the problem of uneven image brightness, that is, the brightness of the center area of ​​the image is higher, while the brightness of the edge area of ​​the image is lower. Summary of the Invention

[0004] In view of the above problems, this application proposes an AR waveguide and an AR waveguide that can effectively improve the uniformity of image brightness, thereby improving the image display effect.

[0005] In a first aspect, embodiments of this application provide an AR waveguide and an AR device, the AR waveguide and the AR device comprising: a first optical waveguide and a second optical waveguide; the first optical waveguide comprising a first optical waveguide body, a first entrance pupil region, a first bend region, a second bend region, a first exit pupil region and a second exit pupil region; the first bend region and the first exit pupil region are disposed on one side of the first entrance pupil region; the second bend region and the second exit pupil region are disposed on the other side of the first entrance pupil region; the second optical waveguide comprises at least a second optical waveguide body, a second entrance pupil region and a third exit pupil region; the projection of the second entrance pupil region onto the surface where the first entrance pupil region is located overlaps at least partially with the first entrance pupil region; the projection of the third exit pupil region onto the surface where the first bend region or the second bend region is located overlaps with a portion of the area of ​​the first bend region or the second bend region.

[0006] Secondly, embodiments of this application provide an AR device, which includes an optical engine and the aforementioned AR waveguide. The AR waveguide includes a first optical waveguide and a second optical waveguide. The first optical waveguide includes a first optical waveguide body, a first entrance pupil region, a first bend region, a second bend region, a first exit pupil region, and a second exit pupil region. The second optical waveguide includes at least a second optical waveguide body, a second entrance pupil region, and a third exit pupil region. The optical engine is used to direct light into the first entrance pupil region. The first optical waveguide outputs an image through a first path in the first and second exit pupil regions. The first and second optical waveguides output a compensated image through a second path in the first and / or second exit pupil regions.

[0007] The technical solution provided in this application includes an AR waveguide and an AR device comprising: a first optical waveguide and a second optical waveguide; the first optical waveguide includes a first optical waveguide body, a first entrance pupil region, a first turning region, a second turning region, a first exit pupil region, and a second exit pupil region; the first turning region and the first exit pupil region are disposed on one side of the first entrance pupil region; the second turning region and the second exit pupil region are disposed on the other side of the first entrance pupil region; the second optical waveguide includes at least a second optical waveguide body, a second entrance pupil region, and a third exit pupil region; the projection of the second entrance pupil region onto the surface where the first entrance pupil region is located at least partially overlaps with the first entrance pupil region; the projection of the third exit pupil region onto the surface where the first turning region or the second turning region is located overlaps with a portion of the area of ​​the first turning region or the second turning region. Therefore, by setting the second optical waveguide to increase the image beam coupled out of the second exit pupil region, the brightness of one edge of the image presented by the image beam is increased, thereby reducing the phenomenon of low brightness in the image edge region, improving the image display effect, and thus improving the user experience. Attached Figure Description

[0008] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments and drawings obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0009] Figure 1 A schematic diagram of an AR waveguide provided in an embodiment of this application is shown.

[0010] Figure 2 A schematic diagram of the structure of a first optical waveguide provided in an embodiment of this application is shown.

[0011] Figure 3 A schematic diagram of an image beam propagation path provided in an embodiment of this application is shown.

[0012] Figure 4 A schematic diagram of another image beam propagation path provided in an embodiment of this application is shown.

[0013] Figure 5 This illustration shows a structural schematic diagram of another image beam propagation path provided in an embodiment of this application.

[0014] Figure 6 A schematic diagram of another AR waveguide structure provided in an embodiment of this application is shown.

[0015] Figure 7 This illustration shows a structural diagram of an image provided in an embodiment of this application.

[0016] Figure 8 A schematic diagram of another AR waveguide provided in an embodiment of this application is shown.

[0017] Figure 9 A schematic diagram of another AR waveguide provided in an embodiment of this application is shown.

[0018] Figure 10 A schematic diagram of another first optical waveguide provided in an embodiment of this application is shown.

[0019] Figure 11 A schematic diagram of the structure of the AR device provided in an embodiment of this application is shown. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this application clearer, the application will be further described in detail below with reference to the accompanying drawings. The described embodiments should not be regarded as limitations on this application. All other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0021] In the following description, references to "some embodiments" describe a subset of all possible embodiments; however, it is understood that "some embodiments" may be the same subset or different subsets of all possible embodiments and may be combined with each other without conflict. In the following description, the term "a plurality of" means at least two.

[0022] In the following description, the terms "first" and "second" are used merely to distinguish similar objects and do not represent a specific ordering of objects. It is understood that "first" and "second" may be interchanged in a specific order or sequence where permitted, so that the embodiments of this application described herein can be implemented in an order other than that illustrated or described herein.

[0023] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing embodiments of this application only and is not intended to limit this application.

[0024] Augmented Reality (AR) technology is widely used in various fields such as gaming, education, and healthcare. AR devices provide users with an immersive experience by combining virtual information with the real world. As one of the key hardware components of AR technology, AR glasses need to possess characteristics such as lightweight design, high resolution, a large field of view (FOV), high brightness, and low power consumption to meet users' needs for wearing comfort and experience. The optical display system in AR glasses typically employs waveguide display technology, with waveguide sheets as its core component. Waveguide sheets split, guide, and output the image beam displayed by the optomechanical system to achieve the transmission and display of virtual images.

[0025] In practical optical display systems, due to the long propagation path of light in the waveguide, the light gradually attenuates with multiple total internal reflections, resulting in gradual energy loss. Especially when the light propagates to the edge area of ​​the image, the light intensity is significantly lower than that in the center area, which causes the problem of uneven image brightness, that is, the brightness of the center area of ​​the image is higher, while the brightness of the edge area of ​​the image is lower.

[0026] In related technologies, a non-uniform grating design is employed to gradually improve the coupling efficiency of the waveguide sheet along the light propagation path, thereby matching the intensity of the coupled light with the energy loss of the light and improving the unevenness of image brightness. Specifically, the depth of the grating is not the same in different regions of the waveguide sheet, resulting in different diffraction efficiencies in different regions, with higher diffraction efficiency in regions where light arrives later.

[0027] In another related technology, a gradient grating design can be used to control the coupling efficiency of different regions of the waveguide, thereby achieving precise optical energy compensation and optical uniformity. Specifically, the coupling efficiency of different regions can be controlled by changing the period, depth, or duty cycle of the grating on the waveguide.

[0028] However, the high complexity of the grating design and the high precision requirements for grating fabrication in the aforementioned technologies result in low generation efficiency. Furthermore, the material of the waveguide itself also causes energy loss in the light, leading to a phenomenon where the central area of ​​the image is brighter than the edge areas.

[0029] To address the aforementioned issues, this application provides an AR waveguide and an AR device. The AR waveguide includes a first optical waveguide and a second optical waveguide. The first optical waveguide includes a first optical waveguide body, a first entrance pupil region, a first bend region, a second bend region, a first exit pupil region, and a second exit pupil region. The first bend region and the first exit pupil region are located on one side of the first entrance pupil region. The second bend region and the second exit pupil region are located on the other side of the first entrance pupil region. The second optical waveguide includes at least a second optical waveguide body, a second entrance pupil region, and a third exit pupil region. The projection of the second entrance pupil region onto the surface of the first entrance pupil region at least partially overlaps with the first entrance pupil region. The projection of the third exit pupil region onto the surface of the first bend region or the second bend region overlaps with a portion of the area of ​​the first bend region or the second bend region.

[0030] Therefore, by setting a second optical waveguide to increase the image beam coupled out of the second exit pupil region, the brightness of one edge of the image presented by the image beam is increased, thereby reducing the phenomenon of low brightness in the image edge region, thus improving the image display effect and improving the user experience.

[0031] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings.

[0032] Please see Figure 1 and Figure 2 , Figure 1 This paper shows a schematic diagram of an AR waveguide structure provided in an embodiment of this application. Figure 2 A schematic diagram of the structure of a first optical waveguide provided in an embodiment of this application is shown. Figure 1 and Figure 2 As shown, the AR waveguide 100 includes a first optical waveguide 120 and a second optical waveguide 130, wherein:

[0033] The first optical waveguide 120 includes a first optical waveguide body 121, a first entrance pupil region 122, a first turning region 123, a second turning region 124, a first exit pupil region 125, and a second exit pupil region 126; the first turning region 123 and the first exit pupil region 125 are disposed on one side of the first entrance pupil region 122; the second turning region 124 and the second exit pupil region 126 are disposed on the other side of the first entrance pupil region 122.

[0034] The second optical waveguide 130 includes a second optical waveguide body 131, a second entrance pupil region 132, and a third exit pupil region 133. The projection of the second entrance pupil region 132 onto the surface where the first entrance pupil region 122 is located at least partially overlaps with the first entrance pupil region 122.

[0035] The projection of the third exit pupil region 133 onto the surface where the first turning region 123 or the second turning region 124 is located overlaps with part of the area of ​​the first turning region 123 or the second turning region 124.

[0036] The projection of the third exit pupil region 133 onto the surface of the first transition region 123 or the second transition region 124 overlaps with a portion of the area of ​​the first transition region 123 or the second transition region 124, so that the image beam coupled out of the third exit pupil region is at least partially coupled into the first transition region 123 or the second transition region 124, thereby enabling the first optical waveguide 120 and the second optical waveguide 130 to cooperate with each other, thereby improving the brightness of one edge of the image presented by the image beam.

[0037] The first optical waveguide 120 includes two imaging paths. The first path is the imaging optical path on the first optical waveguide 120: light ray—first entrance pupil region 122—first turning region 123—first exit pupil region 125 outputs the first image, and light ray—first entrance pupil region 122—second turning region 124—second exit pupil region 126 outputs the second image.

[0038] The second path is the imaging optical path that passes through the second optical waveguide and then returns to the first optical waveguide: Optical mechanism 110 — First entrance pupil region 122 — Second entrance pupil region 132 — Third exit pupil region 133 — First turning region 123 — First exit pupil region 123 — Second turning region 124 — Second exit pupil region 126 Output the compensated part of the image.

[0039] The distance from the center of the second entrance pupil region 132 to the center of the third exit pupil region 133 is greater than the distance from the center of the first entrance pupil region 122 to the first turning region 123, so as to compensate for the brightness of the image at a greater distance from the entrance pupil.

[0040] The optical engine 110 is used to emit an image beam into the first entrance pupil region 122; the image beam coupled out of the first entrance pupil region 122 is at least partially coupled into the second entrance pupil region 132; and the image beam coupled out of the third exit pupil region 133 is at least partially coupled into the first turning region 123.

[0041] The optical engine 110 can be a micro projector, such as a DLP projector, an LCOS projector, or a micro light-emitting diode (MicroLED).

[0042] The first optical waveguide body 121 and the second optical waveguide body 131 can be diffractive optical waveguides.

[0043] The first entrance pupil region 122, the first inflection region 123, the second inflection region 124, the first exit pupil region 125, and the second exit pupil region 126 can be diffraction gratings.

[0044] The second entrance pupil region 132 and the third exit pupil region 133 can be relief diffraction gratings.

[0045] In one specific embodiment, a first entrance pupil region 122, a first bend region 123, a second bend region 124, a first exit pupil region 125, and a second exit pupil region 126 are disposed on the lower surface of the first optical waveguide body 121. A second entrance pupil region 132 and a third exit pupil region 133 are disposed on the lower surface of the second optical waveguide body 131.

[0046] In another specific embodiment, a first entrance pupil region 122, a first turning region 123, a second turning region 124, a first exit pupil region 125, and a second exit pupil region 126 are disposed on the upper surface of the first optical waveguide body 121. A second entrance pupil region 132 and a third exit pupil region 133 are disposed on the upper surface of the second optical waveguide body 131.

[0047] It is understood that this application does not limit whether the first entrance pupil region 122, the first turning region 123, the second turning region 124, the first exit pupil region 125, and the second exit pupil region 126 are respectively disposed on the upper or lower surface of the first optical waveguide body 121. That is, some regions of the first entrance pupil region 122, the first turning region 123, the second turning region 124, the first exit pupil region 125, and the second exit pupil region 126 are disposed on the upper surface of the first optical waveguide body 121, and other regions are disposed on the lower surface of the first optical waveguide body 121.

[0048] Similarly, this application does not limit whether the second entrance pupil region 132 and the third exit pupil region 133 are located on the upper or lower surface of the second optical waveguide body 131. For example, the second entrance pupil region 132 can be located on the upper surface of the second optical waveguide body 131, and the third exit pupil region 133 can be located on the lower surface of the second optical waveguide body 131. As another example, the second entrance pupil region 132 can be located on the lower surface of the second optical waveguide body 131, and the third exit pupil region 133 can be located on the upper surface of the second optical waveguide body 131.

[0049] In other words, after the optical engine 110 emits an image beam into the first entrance pupil region 122, the image beam is coupled into the first entrance pupil region 122 and coupled into the first optical waveguide body 121. Part of the image beam undergoes multiple reflections within the first optical waveguide body 121 and then reaches the first turning region 123 and the second turning region 124. Meanwhile, part of the image beam is coupled out of the first optical waveguide body 121 and propagates in the direction of the second entrance pupil region 132, and then the second entrance pupil region 132 couples this part of the image beam into the second optical waveguide body 131.

[0050] For more details, please refer to... Figure 2An image beam coupled into the first optical waveguide body 121 from the first entrance pupil region 122 is at least partially propagated to the first turning region 123 and the second turning region 124. The first turning region 123 and the second turning region 124 propagate at least part of the image beam coupled into the first optical waveguide body 121 from the first entrance pupil region 122 to the first exit pupil region 125 and the second exit pupil region 126, so as to couple the image beam out of the first optical waveguide body 121 through the first exit pupil region 125 and the second exit pupil region 126.

[0051] In other words, the propagation path of the image beam is: Optical mechanism 110 – first entrance pupil region 122 – first turning region 123 – first exit pupil region 125; Optical mechanism 110 – first entrance pupil region 122 – second turning region 124 – second exit pupil region 126.

[0052] Therefore, the image beam emitted by the optical engine 110 can be coupled out of the first optical waveguide body 121 in the first exit pupil region 125 and the second exit pupil region 126, and the image beam can be obtained at the position where the image beam is coupled out in the first exit pupil region 125 and the second exit pupil region 126, thereby obtaining the display content corresponding to the image beam.

[0053] However, during the process from the image beam entering the first optical waveguide body 121 from the first entrance pupil region 122 to the image beam exiting the first optical waveguide body 121 from the first exit pupil region 125 and the second exit pupil region 126, due to the long propagation path of the image beam and the multiple reflections of the image beam within the first optical waveguide body 121, the image beam will gradually attenuate, resulting in a gradual loss of energy. Consequently, the brightness of the edge region of the image formed by the image beam is less than that of the center region of the image, leading to uneven image brightness and thus affecting the imaging effect of the AR waveguide.

[0054] Based on the above, please refer to Figure 3 , Figure 3 A schematic diagram of an image beam propagation path provided in an embodiment of this application is shown. Figure 3 As shown, by setting a second optical waveguide 130, and by having the third exit pupil region 133 on the second optical waveguide 130 cooperate with the first turning region 123, the brightness of the edge region of the image formed by the image beam is compensated, thereby reducing the unevenness of image brightness and improving the imaging effect of the AR waveguide.

[0055] Specifically, at least a portion of the image beam coupled to the second optical waveguide body 130 from the second entrance pupil region 132 propagates to the third exit pupil region 133, so that the image beam coupled to the second optical waveguide body 130 from the second entrance pupil region 132 is coupled out of the second optical waveguide body 130 through the third exit pupil region 133. The first turning region 123 propagates at least a portion of the image beam coupled out of the third exit pupil region 133 to the first exit pupil region 123, so that the image beam coupled out of the third exit pupil region 133 is propagated to the second turning region 124 through the first exit pupil region 125, and then propagated to the second exit pupil region 126 through the second turning region 124, and then coupled out of the first optical waveguide body 120 through the second exit pupil region 126.

[0056] In other words, the propagation path of the image beam is: Optical mechanism 110 — First entrance pupil region 122 — Second entrance pupil region 132 — Third exit pupil region 133 — First turning region 123 — First exit pupil region 123 — Second turning region 124 — Second exit pupil region 126.

[0057] Thus, through the cooperation of the first optical waveguide 120 and the second optical waveguide 130, the image beam coupled out of the first entrance pupil region 122 is at least partially coupled into the second entrance pupil region 132. By reusing the light transmitted through the first entrance pupil region 122, the image beam can be obtained at the position where the image beam is coupled out of the first exit pupil region 125 and the second exit pupil region 126, and an image with relatively uniform brightness can be obtained, thereby improving the user experience.

[0058] That is, by adding a second optical waveguide 130 to increase the energy of the image beam coupled out of the second exit pupil region 126, the brightness of one edge of the image is compensated, thereby improving the uniformity of image brightness.

[0059] In one specific embodiment, please continue to refer to Figure 2 The first entrance pupil region 122 and the second entrance pupil region 132 are located on opposite sides of the second optical waveguide body 131, respectively. The optomechanical system 110 emits an image beam into the first entrance pupil region 122, which couples the image beam into the first optical waveguide body 121. Part of the image beam propagates into the first turning region 123 and the second turning region 124, while part of the image beam exits the first optical waveguide body 121 and propagates into the second entrance pupil region 132, thus coupling into the second optical waveguide body 131 through the second entrance pupil region 132. By cooperating with the first optical waveguide 120 and the second optical waveguide 130, an image beam can be acquired at the positions where the image beam exits from the first exit pupil region 125 and the second exit pupil region 126.

[0060] To further improve the efficiency of the image beam coupled into the second entrance pupil region 132, in some embodiments, the distance between the projection point of the center point of the second entrance pupil region 132 onto the surface where the first entrance pupil region 122 is located and the center point of the first entrance pupil region 122 is less than a preset value.

[0061] In other words, the center point of the first entrance pupil region 122 and the center point of the second entrance pupil region 132 can be slightly offset. It is worth noting that this application does not limit the size relationship between the areas of the first entrance pupil region 122 and the second entrance pupil region 132. That is, the area of ​​the first entrance pupil region 122 is greater than, less than, or equal to the area of ​​the second entrance pupil region 132.

[0062] In a preferred embodiment, the area of ​​the first entrance pupil region 122 is smaller than the area of ​​the second entrance pupil region 132, so that the second entrance pupil region 132 can better couple the image beam coupled from the first entrance pupil region 122, thereby increasing the energy of the image beam coupled from the second exit pupil region 126, thereby improving the brightness of one edge of the image and thus improving the uniformity of image brightness.

[0063] As described above, the AR waveguide 100 includes two sets of image beam propagation paths. By setting a first turning region 123 on the path from which the image beam is coupled out of the third exit pupil region 133, the image beam coupled out of the third exit pupil region 133 is at least partially coupled into the first turning region 123, thereby enhancing the energy of the image beam coupled out of the second exit pupil region 126, thereby increasing the brightness of one edge of the image and improving the uniformity of image brightness.

[0064] The reason why the image beam does not couple out of the first optical waveguide body 121 through the first exit pupil region 125 when it propagates from the first inflection region 123 to the first exit pupil region 125, but instead propagates from the first exit pupil region 125 to the second inflection region 124, is because this part of the image beam is not closed in the K-space (wave vector space).

[0065] Specifically, taking the optical engine 110 as an example of a monochromatic optical engine (such as a single green optical engine, a single red optical engine, or a single blue optical engine), please refer to [the relevant documentation]. Figure 4 , Figure 4 A schematic diagram of another image beam propagation path provided in an embodiment of this application is shown. For example... Figure 4As shown, circle D1 represents a space with a refractive index of air. The space between circles D1 and D2 is the internal space Z1 of the optical waveguide. Box 1 represents the state where the image beam is coupled out of the second optical waveguide body 131 but has not yet reached the first turning region 123 of the first optical waveguide 120. Subsequently, the image beam reaches the first turning region 123 of the first optical waveguide 120 from box 1, forming box 2. The angle between the line connecting box 1 and box 2 and the horizontal direction is the grating vector direction of the first turning region 123 (e.g., 45°). The image beam reaches the first exit pupil region 125 of the first optical waveguide 120 from box 2. A small portion of the image beam propagates towards the second turning region 124, forming box 3. The image beam diffracts this portion of light from the second turning region 124 to the second exit pupil region 126, forming box 4. It then couples out of the second optical waveguide body 131 through box 4, reforming box 1, thus completing the closure in space Z1.

[0066] The lines connecting different boxes represent their diffraction paths in space Z1, and the direction of the diffraction path is consistent with the direction of the grating (grating vector direction) that caused the path.

[0067] It is worth noting that, by Figure 4 It can be seen that some areas of box 2 extend beyond the boundary of circle D2. Areas extending beyond the boundary of circle D2 represent areas that do not exist or leak from the first optical waveguide 120. The reason for this situation may be that the step size of the image beam is too long, and the difference in refractive index between the first optical waveguide 120 and the outside (air) is not large, resulting in a small range of space Z1. This makes the image beam travel a longer distance after one diffraction in space Z1. Therefore, for some long-wavelength image beams, some light rays may extend beyond the boundary of circle D2. However, since some areas of box 2 retain the propagation, it is still possible to enhance the energy of the image beam coupled out of the second exit pupil region 126, thereby increasing the brightness of one edge of the image and improving the uniformity of image brightness.

[0068] The following explanation uses the Optical Engine 110 as an example of a color optical engine (such as a DLP optical engine or an LCOS optical engine). Please refer to [link / reference]. Figure 5 , Figure 5 A schematic diagram of another image beam propagation path provided in an embodiment of this application is shown. For example... Figure 5As shown, when the image beam is coupled out of the third exit pupil region 133 of the second optical waveguide 130, its state in K-space is box 1. It then reaches the first turning region 123 of the first optical waveguide 120, diffracting to form box 2. However, box 2 then splits into three. This is because the step size of image beams of different wavelengths in K-space is inconsistent (the longer the wavelength of the image beam, the longer its step size after one diffraction in K-space). Therefore, for the color optical engine, the three colors RGB are separated after diffraction. Red light may exceed the boundary of circle D2, and blue light may exceed the boundary of circle D1. However, if the space between circle D2 and circle D1 is large enough, it can completely accommodate all RGB rays in the field of view. This depends on the difference in refractive index between the optical waveguide and the air outside the waveguide (the greater the difference, the larger the space). The remaining process is consistent with the above description, except that the image beams are divided into three colors and propagate, finally coupling out from the second exit pupil region 126 of the first optical waveguide 120. This will not be elaborated further here.

[0069] It is worth noting that by combining the first turning region 123 with the third exit pupil region 133, the brightness of one edge of the image can only be improved. Therefore, the above structure is more suitable for situations where the brightness difference between the left and right eyes is large in the imaging of the first optical waveguide 120.

[0070] To accommodate situations where the brightness difference between the left and right eyes is small in the imaging of the first optical waveguide 120, please refer to the following embodiments: Figure 6 , Figure 6 A schematic diagram of another AR waveguide structure provided in an embodiment of this application is shown. Figure 6 As shown, the second optical waveguide 130 also includes a fourth exit pupil region 134, and the image beam coupled out of the fourth exit pupil region 134 is at least partially coupled into the second turning region 124.

[0071] The second optical waveguide 130 also includes a fourth exit pupil region 134, with the third exit pupil region 133 and the fourth exit pupil region 134 disposed on both sides of the second entrance pupil region 132.

[0072] By setting the second inflection region 124 on the path of the image beam coupled out of the fourth exit pupil region 134, the second inflection region 124 couples the image beam coupled out of the fourth exit pupil region 134 into the first optical waveguide body 121, and then propagates from the second inflection region 124 to the second exit pupil region 126, then from the second exit pupil region 126 to the first inflection region 123, and then from the first inflection region 123 to the first exit pupil region 125, so as to couple out of the first optical waveguide body 121 through the first exit pupil region 125, thereby improving the brightness of the image edge.

[0073] In other words, the propagation path of the image beam is: Optical mechanism 110 — First entrance pupil region 122 — Second entrance pupil region 132 — Fourth exit pupil region 134 — Second turning region 124 — Second exit pupil region 126 — First turning region 123 — First exit pupil region 123.

[0074] Please refer to Figure 7 , Figure 7 This illustration shows a structural diagram of an image provided in an embodiment of this application. For example... Figure 7 As shown, 7A is a schematic diagram of the image formed by the user's left eye, and 7B is a schematic diagram of the image formed by the user's right eye. Region a in 7A is a region with low brightness, and region b in 7B is a region with low brightness (due to the larger optical path lengths corresponding to regions a and b). Through the cooperation between the third exit pupil region 133 and the first transition region 123, and the cooperation between the fourth exit pupil region 134 and the second transition region 124, more image beams reach regions a and b, thereby increasing the brightness of regions a and b, improving the uniformity of the overall image brightness, and thus improving the imaging effect of the AR waveguide 100, thereby enhancing the user experience.

[0075] In some embodiments, in order to allow more image beams coupled into the second entrance pupil region 132 to reach the third exit pupil region 133, the second optical waveguide 130 further includes a third turning region and a fourth turning region, which are respectively disposed on both sides of the second entrance pupil region 132.

[0076] Specifically, the image beam coupled to the first optical waveguide body 121 from the second entrance pupil region 132 propagates at least partially to the third and fourth transition regions. The third transition region propagates at least partially of the image beam coupled to the first optical waveguide body 121 from the second entrance pupil region 132 to the third exit pupil region 133; the fourth transition region propagates at least partially of the image beam coupled to the second optical waveguide body 131 from the second entrance pupil region 132 to the fourth exit pupil region 134.

[0077] In one implementation, the third and fourth transition regions can be embossed gratings.

[0078] By setting a third and a fourth transition region in the second optical waveguide 130, the image beam coupled from the second entrance pupil region 132 to the first optical waveguide body 121 is propagated more through the third and fourth transition regions to the third exit pupil region 133 and the fourth exit pupil region 134, thereby improving the coupling of more image beams from the first exit pupil region 125 and the second exit pupil region 126, and thus improving the brightness of the image edge.

[0079] In order to accommodate situations where there is a significant difference in brightness between the left and right eyes in the imaging of the first optical waveguide 120, in some embodiments, the second entrance pupil region 132 is an asymmetric grating, and the depth of the gap between different adjacent grating lines on the second entrance pupil region 132 is different.

[0080] The asymmetric grating can be a slanted grating or a blazed grating. By setting the second entrance pupil region 132 as an asymmetric grating, and making the depth of the gap between different adjacent grating lines on the second entrance pupil region 132 different, the proportion of energy propagating toward the third exit pupil region 133 and the fourth exit pupil region 134 can be adjusted, thereby increasing the energy on the darker side of the image and thus increasing the brightness of the image edge.

[0081] In situations where brightness compensation is not required on one side of the image, the second optical waveguide body 131 may only set the third exit pupil region 133 without setting the fourth exit pupil region 134, or the second optical waveguide body 131 may only set the fourth exit pupil region 134 without setting the third exit pupil region 133, in order to compensate for the brightness of the darker side of the image.

[0082] In some embodiments, the second optical waveguide body 131 is rotatably disposed on the AR waveguide 100, with the center of the third exit pupil region 133 as the rotation point.

[0083] In some embodiments, the second optical waveguide body 131 is rotatably disposed on the AR waveguide 100, with the center of the entrance pupil as the rotation point.

[0084] By rotating the second optical waveguide body 131 relative to the AR waveguide 100, brightness compensation can be avoided on the brighter side of the image when brightness compensation is not required on one side of the image.

[0085] As described above, by cooperating with the first optical waveguide 120 and the second optical waveguide 130, the proportion of energy propagating in the second exit pupil region 126 is increased, or the proportion of energy propagating in the first exit pupil region 125 and the second exit pupil region 126 is increased, thereby increasing the energy on the darker side of the image or increasing the energy at the darker edges of the image, thereby increasing the brightness of the image edges, improving the uniformity of image brightness, and thus improving the user experience.

[0086] To further improve the user experience, in one implementation method, please refer to... Figure 8 , Figure 8 A schematic diagram of another AR waveguide structure provided in an embodiment of this application is shown. Figure 8As shown, 8A is a side view of the second optical waveguide 130, and 8B is a front view of the second optical waveguide 130. The projection of the second optical waveguide body 131 onto the first optical waveguide body 121 is smaller than the area of ​​the first optical waveguide body 121. That is, the area of ​​the second optical waveguide body 131 can be equal to the area of ​​the first optical waveguide body 121, i.e., the shape of the second optical waveguide body 131 can correspond to the shape of the first optical waveguide body 121.

[0087] By setting the area of ​​the second optical waveguide body 131 to be smaller than the area of ​​the first optical waveguide body 121, the weight of the AR waveguide 100 is reduced, thereby improving the user's experience of wearing the AR waveguide 100.

[0088] Furthermore, in one embodiment, please refer to Figure 9 , Figure 9 A schematic diagram of another AR waveguide structure provided in an embodiment of this application is shown. Figure 9 As shown, the first optical waveguide body 121 includes a hollow region 127, which is located between the first exit pupil region 125 and the second exit pupil region 126.

[0089] By setting a hollow area 127 on the first optical waveguide body 121, the weight of the first optical waveguide body 121 is reduced, thereby reducing the weight of the AR waveguide 100 and improving the user's experience of wearing the AR waveguide 100.

[0090] To prevent the cutout area 127 from affecting the propagation of the image beam from the first exit pupil area 125 to the second turning area 124, or from the second exit pupil area 126 to the first turning area 123, in some embodiments, please refer to... Figure 10 , Figure 10 A schematic diagram of another first optical waveguide structure provided in an embodiment of this application is shown. Figure 10 As shown, the height of the hollowed-out area 127 is D; the distance between the midpoint of the first exit pupil area 125 or the second exit pupil area 126 and the lower surface of the first optical waveguide body 121 is X1; the distance between the midpoint of the first exit pupil area 125 and the midpoint of the first turning area 123, or the distance between the midpoint of the second exit pupil area 126 and the midpoint of the second turning area 124 is X2; where D≤X1+1 / 2X2.

[0091] Please continue reading. Figure 10The height of the hollowed-out area 127 is D; the distance between the midpoint of the first exit pupil area 125 or the second exit pupil area 126 and the lower surface of the first optical waveguide body 121 is X1; the distance between the first exit pupil area 125 and the second exit pupil area 126 is X3; and the angle between the line connecting the first exit pupil area 125 and the second exit pupil area 126 and the line connecting the second exit pupil area 126 and the first turning area 123 is A. Where D ≤ X1 + tanA*X3.

[0092] This AR waveguide can be used in fields such as navigation, entertainment, education, medical care, and industrial operations.

[0093] In some embodiments, diffraction gratings are provided in all regions, namely, the first entrance pupil region, the first turning region, the second turning region, the first exit pupil region, the second exit pupil region, the second entrance pupil region, and the third exit pupil region are all provided with diffraction gratings. In other embodiments, a diffraction grating is also provided in the fourth exit pupil region.

[0094] Please refer to Figure 11 , Figure 11 A schematic diagram of the structure of an AR device provided in an embodiment of this application is shown. Figure 11 As shown, Figure 11 The AR device 200 includes an optical engine 110 and the aforementioned AR waveguide 100, wherein:

[0095] AR waveguide 100 includes a first optical waveguide 120 and a second optical waveguide 130. The first optical waveguide 120 includes a first optical waveguide body, a first entrance pupil region, a first bend region, a second bend region, a first exit pupil region, and a second exit pupil region. The second optical waveguide 130 includes at least a second optical waveguide body, a second entrance pupil region, and a third exit pupil region.

[0096] Specifically, the optical engine 110 is used to direct light into the first entrance pupil region.

[0097] The first optical waveguide 120 outputs an image through a first path in the first exit pupil region and the second exit pupil region.

[0098] The first optical waveguide 120 and the second optical waveguide 130 output compensated images through a second path in the first exit pupil region and / or the second exit pupil region.

[0099] In some embodiments, the image beam coupled from the first entrance pupil region is at least partially coupled into the second entrance pupil region.

[0100] It is understandable that the above description can be used as a reference for how the Optical Mechanism 110 and the AR Waveguide 100 work together, and will not be repeated here.

[0101] This application provides an AR waveguide and an AR waveguide, which includes: a first optical waveguide and a second optical waveguide; the first optical waveguide includes a first optical waveguide body, a first entrance pupil region, a first turning region, a second turning region, a first exit pupil region, and a second exit pupil region; the first turning region and the first exit pupil region are disposed on one side of the first entrance pupil region; the second turning region and the second exit pupil region are disposed on the other side of the first entrance pupil region; the second optical waveguide includes at least a second optical waveguide body, a second entrance pupil region, and a third exit pupil region; the projection of the second entrance pupil region onto the surface where the first entrance pupil region is located at least partially overlaps with the first entrance pupil region; the projection of the third exit pupil region onto the surface where the first turning region or the second turning region is located overlaps with a portion of the area of ​​the first turning region or the second turning region. Therefore, by setting the second optical waveguide to increase the image beam coupled out of the second exit pupil region, the brightness of one edge of the image presented by the image beam is increased, thereby reducing the phenomenon of low brightness in the image edge region, improving the image display effect, and thus improving the user experience.

[0102] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. An AR waveguide, characterized in that, The AR waveguide includes a first optical waveguide and a second optical waveguide; The first optical waveguide includes a first optical waveguide body, a first entrance pupil region, a first bend region, a second bend region, a first exit pupil region, and a second exit pupil region; the first bend region and the first exit pupil region are disposed on one side of the first entrance pupil region; the second bend region and the second exit pupil region are disposed on the other side of the first entrance pupil region; The second optical waveguide includes at least a second optical waveguide body, a second entrance pupil region, and a third exit pupil region; The projection of the second entrance pupil region onto the surface where the first entrance pupil region is located overlaps with the first entrance pupil region in at least part; The projection of the third exit pupil region onto the surface where the first or second turning region is located overlaps with a portion of the area of ​​the first or second turning region. The third exit pupil region is used to direct the output light to the first or second turning region before it enters the first optical waveguide. The first optical waveguide includes two imaging paths, namely the first path and the second path. The first path is the imaging optical path on the first optical waveguide: light ray - first entrance pupil region - first turning region - first exit pupil region to output the first image, and light ray - first entrance pupil region - second turning region - second exit pupil region to output the second image. The second path is an imaging optical path that passes through the second optical waveguide and then returns to the first optical waveguide: Optical engine — first entrance pupil region — second entrance pupil region — third exit pupil region — first turning region — first exit pupil region — second turning region — second exit pupil region outputs a compensated portion of the image.

2. The AR waveguide according to claim 1, characterized in that, The second optical waveguide also includes a fourth exit pupil region, with the third and fourth exit pupil regions located on either side of the second entrance pupil region.

3. The AR waveguide according to claim 2, characterized in that, The second path also includes another path, which is: the first entrance pupil region – the second entrance pupil region – the fourth exit pupil region – the second turning region – the second exit pupil region – the first turning region – the first exit pupil region.

4. The AR waveguide according to claim 2, characterized in that, The distance from the center of the second entrance pupil region to the third exit pupil region is greater than the distance from the center of the first entrance pupil region to the first turning region.

5. The AR waveguide according to claim 1, characterized in that, The distance between the projection point of the center point of the second entrance pupil region onto the surface where the first entrance pupil region is located and the center point of the first entrance pupil region is less than a preset value.

6. The AR waveguide according to claim 1, wherein diffraction gratings are provided in all regions.

7. The AR waveguide according to claim 1, characterized in that, The number of third exit pupil regions is one, the second entrance pupil region is an asymmetric grating, and the depth of the gap between different adjacent grating lines on the second entrance pupil region is different.

8. The AR waveguide according to claim 1, characterized in that, The first optical waveguide body includes a hollow area, which is located between the first exit pupil area and the second exit pupil area. The hollow area allows light to propagate uninterruptedly from the first turning area and the second exit pupil area.

9. An AR device, characterized in that, Including an optical engine and an AR waveguide as described in any one of claims 1-8, the AR waveguide comprising a first optical waveguide and a second optical waveguide, the first optical waveguide comprising a first optical waveguide body, a first entrance pupil region, a first bend region, a second bend region, a first exit pupil region, and a second exit pupil region, the second optical waveguide comprising at least a second optical waveguide body, a second entrance pupil region, and a third exit pupil region, wherein: The optical engine is used to direct light rays into the first entrance pupil region; The first optical waveguide outputs images in the first exit pupil region and the second exit pupil region through the first path; The first optical waveguide and the second optical waveguide output compensated images in the first exit pupil region and / or the second exit pupil region through the second path.

10. The AR device according to claim 9, characterized in that, The image beam coupled from the first entrance pupil region is at least partially coupled into the second entrance pupil region.

Images