Optical waveguide device and display apparatus

Abstract

The application discloses an optical waveguide device, wherein a first optical element and a second optical element are arranged on the upper surface and the lower surface of a waveguide substrate or in the waveguide substrate, a first area of the first optical element and a first area of the second optical element cover each other, and the first area of the first optical element and the first area of the second optical element diffract the light propagating in the waveguide substrate to change the propagation mode of at least part of the light. At least one of the first optical element and the second optical element comprises a second area which is not covered by the other optical element, and the second area diffracts the light propagating in the waveguide substrate to make at least part of the light propagate along the waveguide substrate to the first area of the first optical element or the first area of the second optical element. The application can reduce the loss of optical energy and improve the utilization rate of optical energy. The application also discloses a display device.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of optical devices, in particular to an optical waveguide device. The present application also relates to a display device. BACKGROUND

[0002] In a near-eye display device, light carrying image information output by a projection light engine is propagated to a position in front of a human eye using an optical waveguide, so that the light enters the human eye to realize virtual image imaging.

[0003] In the prior art, when the light propagates along the optical waveguide to the coupling-out region, at least part of the energy of the propagating light is coupled out of the optical waveguide, and the remaining part of the light continues to propagate along the optical waveguide. The light that continues to propagate to the boundary of the coupling-out region will exit the coupling-out region, and this part of the light energy is lost. Therefore, the light energy utilization rate of the existing optical waveguide scheme is low. SUMMARY

[0004] The purpose of the present application is to provide an optical waveguide device that can improve the light energy utilization rate. The present application also provides a display device.

[0005] To achieve the above-mentioned purpose, the present application provides the following technical solutions:

[0006] An optical waveguide device includes a waveguide substrate, a first optical element, and a second optical element, the first optical element and the second optical element are arranged on the upper surface, the lower surface of the waveguide substrate or in the waveguide substrate, the first region of the first optical element and the first region of the second optical element are overlapped with each other, at least one of the first optical element and the second optical element includes a second region, the second region is a region without covering the other optical element;

[0007] The first region of the first optical element and the first region of the second optical element cause the light propagating in the waveguide substrate to diffract so that at least part of the light changes the form of propagation, and the second region causes the light propagating in the waveguide substrate to diffract so that at least part of the light propagates along the waveguide substrate to the first region of the first optical element or the first region of the second optical element.

[0008] Preferably, the first optical element includes the second region, and the second region is located on one side of the first region of the first optical element.

[0009] Alternatively, the second optical element includes the second region, and the second region is located on one side of the first region of the second optical element.

[0010] Preferably, the first optical element includes the second region, and the second region is surrounded by the first region of the first optical element.

[0011] Alternatively, the second optical element comprises the second region, and the first region of the second optical element surrounds the second region.

[0012] Preferably, the first optical element and the second optical element are respectively located in different planes in the thickness direction of the waveguide substrate.

[0013] Preferably, the first optical element and the second optical element are located in the same plane in the thickness direction of the waveguide substrate.

[0014] Preferably, the first optical element comprises at least one second region, and / or the second optical element comprises at least one second region.

[0015] Preferably, the second region diffracts the light propagating in the waveguide substrate, so that at least part of the light propagates along a one-dimensional direction of the waveguide substrate, and at least another part of the light propagates along another one-dimensional direction of the waveguide substrate, so as to realize the propagation of at least part of the light along the waveguide substrate to the first region of the first optical element or the first region of the second optical element.

[0016] Preferably, the first optical element comprises the second region, and the unit structure arrangement period of the first region of the first optical element is consistent with the unit structure arrangement period of the second region of the first optical element.

[0017] Alternatively, the second optical element comprises the second region, and the unit structure arrangement period of the first region of the second optical element is consistent with the unit structure arrangement period of the second region of the second optical element.

[0018] Preferably, the first region of the first optical element and the first region of the second optical element cooperate to make the light propagating in the waveguide substrate expand along two-dimensional directions.

[0019] A display device comprises an image projection device for generating light rays, and a light waveguide device for receiving the light rays, wherein the light waveguide device is the light waveguide device as described above.

[0020] According to the above technical solution, the light waveguide device provided by the application comprises a first optical element and a second optical element arranged on or in a waveguide substrate, and a first region of the first optical element and a first region of the second optical element are overlapped with each other, and the first region of the first optical element and the first region of the second optical element diffract the light propagating in the waveguide substrate to change the propagation form of at least part of the light.

[0021] At least one of the first optical element and the second optical element comprises a second region, the second region is a region without covering the other optical element, and the second region causes the light propagating in the waveguide substrate to diffract so that at least part of the light propagates along the waveguide substrate to the first region of the first optical element or the first region of the second optical element. Thus, by the second region, the light propagating to the second region is caused to propagate at least partially to the first region of the first optical element or the first region of the second optical element, and the light energy loss can be reduced, and the light energy utilization rate can be improved.

[0022] The present application also provides a display device, which can achieve the above beneficial effects. BRIEF DESCRIPTION OF DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative effort.

[0024] Figure 1 A schematic diagram of an optical waveguide device according to an embodiment of the present application;

[0025] Figure 2 A schematic diagram of an optical waveguide device according to another embodiment of the present application;

[0026] Figure 3 A schematic diagram of light propagation in the first region and the second region of an optical waveguide device according to an embodiment of the present application;

[0027] Figure 4 A schematic diagram of light propagation in the first region and the second region of an optical waveguide device according to another embodiment of the present application;

[0028] Figure 5 A schematic diagram of the arrangement of the second region of the first optical element and the second region of the second optical element in an optical waveguide device according to another embodiment of the present application;

[0029] Figure 6 A schematic diagram of an optical waveguide device according to an embodiment of the present application; Figure 5 A schematic diagram of an actual implementation state of an embodiment of the present application;

[0030] Figure 7 A schematic diagram of the arrangement of the second region of the first optical element and the second region of the second optical element in an optical waveguide device according to another embodiment of the present application. DETAILED DESCRIPTION

[0031] In order to make the person skilled in the art better understand the technical solutions in the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by the person skilled in the art without creative labor should belong to the protection scope of the present application.

[0032] The present embodiment provides an optical waveguide device, comprising a waveguide substrate, a first optical element and a second optical element, the first optical element and the second optical element are arranged on the upper surface or the lower surface of the waveguide substrate or in the waveguide substrate, the first region of the first optical element and the first region of the second optical element cover each other, at least one of the first optical element and the second optical element comprises a second region, the second region is a region without covering the other optical element;

[0033] The first region of the first optical element and the first region of the second optical element make the light propagating in the waveguide substrate diffract to change the propagation form of at least part of the light, and the second region makes the light propagating in the waveguide substrate diffract to propagate at least part of the light along the waveguide substrate to the first region of the first optical element or the first region of the second optical element.

[0034] Each of the first region of the first optical element and the first region of the second optical element makes the light propagating in the waveguide substrate diffract when the light is incident to the first region to change the propagation form of at least part of the light.

[0035] The light propagating in the waveguide substrate diffracts when the light is incident to the second region, and the second region makes the light propagating in the waveguide substrate propagate at least part of the light along the waveguide substrate to the first region of the first optical element or the first region of the second optical element. Thus, by making the light propagating to the second region propagate at least part of the light to the first region of the first optical element or the first region of the second optical element through the second region, the part of the light can be avoided from being completely lost, the loss of light energy can be reduced, and the utilization rate of light energy can be improved.

[0036] In the above description, the second region can be the second region included in the first optical element, or the second region can be the second region included in the second optical element.

[0037] Exemplary reference can be made to Figure 1 , Figure 1A schematic diagram of an optical waveguide device provided in an embodiment is shown in the figure. The optical waveguide device includes a waveguide substrate 100, a first optical element 101 and a second optical element 102. The first region 103 of the first optical element 101 and the first region 104 of the second optical element 102 are overlaid on each other.

[0038] The first optical element 101 further includes a second region 105. The second region 105 of the first optical element 101 is not overlaid on the second optical element 102. When light propagating in the waveguide substrate 100 is incident on the second region 105 of the first optical element 101, diffraction occurs, causing at least part of the light to propagate along the waveguide substrate 100 towards the first region 103 of the first optical element 101 or the first region 104 of the second optical element 102.

[0039] For another example, please refer to Figure 2 , Figure 2 A schematic diagram of an optical waveguide device provided in another embodiment is shown in the figure. The optical waveguide device includes a waveguide substrate 100, a first optical element 101 and a second optical element 102. The first region 103 of the first optical element 101 and the first region 104 of the second optical element 102 are overlaid on each other. The second optical element 102 further includes a second region 106. The second region 106 of the second optical element 102 is not overlaid on the first optical element 101. When light propagating in the waveguide substrate 100 is incident on the second region 106, diffraction occurs, causing at least part of the light to propagate along the waveguide substrate 100 towards the first region 103 of the first optical element 101 or the first region 104 of the second optical element 102.

[0040] In Figure 1 and Figure 2 , the first optical element 101 includes a second region or the second optical element 102 includes a second region is exemplified. In other embodiments, the first optical element 101 and the second optical element 102 can each include a second region.

[0041] The first region 103 of the first optical element 101 can include a periodic arrangement of unit structures, such that when light is incident on the first region 103 of the first optical element 101, diffraction occurs. If the first optical element 101 includes a second region, the second region of the first optical element 101 can include a periodic arrangement of unit structures, such that when light is incident on the second region of the first optical element 101, diffraction occurs. In the present embodiment, the specific structure of the unit structures of the first region 103 of the first optical element 101 is not limited, and the specific structure of the unit structures of the second region of the first optical element 101 is not limited. In actual applications, the unit structures can be designed according to application requirements.

[0042] Preferably, if the first optical element 101 comprises a second region, the first region 103 and the second region of the first optical element 101 respectively comprise unit structures arranged periodically, and the arrangement period of the unit structures of the first region 103 of the first optical element 101 is consistent with the arrangement period of the unit structures of the second region of the first optical element 101. Such arrangement can make the light propagating along the waveguide substrate 100 from the first region 103 of the first optical element 101 to the second region of the first optical element 101, and when passing through the second region, at least part of the light can be made to propagate reversely, i.e., to propagate in a direction opposite to the original propagation direction, and return to the first region 103 of the first optical element 101.

[0043] The first region 104 of the second optical element 102 can comprise unit structures arranged periodically, so that when light is incident on the first region 104 of the second optical element 102, diffraction occurs. If the second optical element 102 comprises a second region, the second region of the second optical element 102 can comprise unit structures arranged periodically, so that when light is incident on the second region of the second optical element 102, diffraction occurs. In the present embodiment, the specific structure of the unit structures of the first region 104 of the second optical element 102 is not limited, and the specific structure of the unit structures of the second region of the second optical element 102 is not limited, and in actual application, it can be designed according to the application requirements.

[0044] Preferably, if the second optical element 102 comprises a second region, the first region 104 and the second region of the second optical element 102 respectively comprise unit structures arranged periodically, and the arrangement period of the unit structures of the first region 104 of the second optical element 102 is consistent with the arrangement period of the unit structures of the second region of the second optical element 102. Such arrangement can make the light propagating along the waveguide substrate 100 from the first region 104 of the second optical element 102 to the second region of the second optical element 102, and when passing through the second region, at least part of the light can be made to propagate reversely, i.e., to propagate in a direction opposite to the original propagation direction, and return to the first region 104 of the second optical element 102.

[0045] The second region in the present application makes at least part of the light to propagate reversely based on the diffraction principle, which is not described here.

[0046] Optionally, the second region of the first optical element 101 or the second region of the second optical element 102 can make the light propagating in the waveguide substrate 100 to diffract, change the propagation direction of at least part of the light, and make at least part of the light propagate along the one-dimensional direction of the waveguide substrate 100, so that the light reaching the second region propagates at least partially along the waveguide substrate 100 to the first region 103 of the first optical element 101 or the first region 104 of the second optical element 102. For example, refer to Figure 3 As shown,Figure 3 For the light propagation in the first region and the second region of the optical waveguide device of an embodiment, as shown in the figure, the first region 103 of the first optical element and the first region 104 of the second optical element can expand the light propagating in the waveguide substrate 100 in two dimensions (as shown by the solid arrows in the figure, the direction of the arrow indicates the direction of light propagation). When the light is incident on the second region 106 of the second optical element, diffraction occurs, and at least part of the light propagates in one dimension of the waveguide substrate 100, and returns to the first region 103 and the first region 104 (as shown by the dashed arrows in the figure, the direction of the arrow indicates the direction of light propagation). Optionally, the second region of the first optical element 101 or the second region of the second optical element 102 can include unit structures arranged periodically in one dimension, and the unit structures arranged in this way can cause the light to diffract, and at least part of the light changes the direction of propagation and propagates in one direction.

[0047] Optionally, the second region of the first optical element 101 or the second region of the second optical element 102 causes the light propagating in the waveguide substrate 100 to diffract, and at least part of the light propagates in one dimension of the waveguide substrate 100, and at least another part of the light propagates in another dimension of the waveguide substrate 100, so as to achieve the propagation of at least part of the light to the first region of the first optical element 101 or the first region of the second optical element 102 along the waveguide substrate 100. When the light propagating in the waveguide substrate 100 reaches the second region of the first optical element 101 or the second region of the second optical element 102, diffraction occurs, and at least part of the light propagates in one dimension of the waveguide substrate 100, and at least another part of the light propagates in another dimension of the waveguide substrate 100, and the two parts of light propagate to the first region of the first optical element 101 or the first region of the second optical element 102 respectively, achieving the recovery of light in two dimensions. For an example, reference can be made to Figure 4 Figure 4 For the light propagation in the first region and the second region of the optical waveguide device of an embodiment, as shown in the figure, the first region 103 of the first optical element and the first region 104 of the second optical element can expand the light propagating in the waveguide substrate 100 in two dimensions (as shown by the solid arrows in the figure, the direction of the arrow indicates the direction of light propagation). When the light is incident on the second region 106 of the second optical element, diffraction occurs, and at least part of the light propagates in one direction of the waveguide substrate 100, and at least another part of the light propagates in another direction of the waveguide substrate 100, and the light returns to the first region 103 and the first region 104 (as shown by the dashed arrows in the figure, the direction of the arrow indicates the direction of light propagation). For an example, the second region of the first optical element 101 or the second region of the second optical element 102 can include unit structures arranged periodically in two dimensions.

[0048] ​If the first optical element 101 comprises a second region, the arrangement position, shape or size of the second region comprised by the first optical element 101 is not limited in the embodiment; if the second optical element 102 comprises a second region, the arrangement position, shape or size of the second region comprised by the second optical element 102 is not limited in the embodiment. In actual application, the first optical element 101 or the second optical element 102 can be designed according to the specific conditions of the first region or the second region, the application requirement of the optical waveguide device, etc.

[0049] Optionally, if the first optical element 101 comprises a second region, the second region can be located at one side of the first region 103 of the first optical element 101. For example, the second region 105 of the first optical element 101 can be located at one side of the first region 103 of the first optical element 101, as shown in FIG. 1B. Figure 1 Optionally, if the first optical element 101 comprises a second region, the second region can be located at one side of the first region 103 of the first optical element 101. For example, the second region 105 of the first optical element 101 can be located at one side of the first region 103 of the first optical element 101, as shown in FIG. 1B. Figure 2 Optionally, if the first optical element 101 comprises a second region, the second region can be located at one side of the first region 103 of the first optical element 101. For example, the second region 105 of the first optical element 101 can be located at one side of the first region 103 of the first optical element 101, as shown in FIG. 1B.

[0050] Optionally, the first optical element 101 can comprise at least one second region, and / or the second optical element 102 can comprise at least one second region, the first optical element 101 or the second optical element 102 can comprise a plurality of second regions, and the arrangement position, shape or size of each second region can be set according to the coverage range of the first optical element 101 on the waveguide substrate 100, the coverage range of the second optical element 102 on the waveguide substrate 100 or the application requirement of the optical waveguide device. For example, the first optical element 101 can comprise a plurality of second regions, and the arrangement position, shape or size of each second region can be set according to the coverage range of the first optical element 101 on the waveguide substrate 100, as shown in FIG. 1C. Figure 5 , Figure 5This is a schematic diagram illustrating the arrangement of the second regions of the first optical element and the second optical element in another embodiment of an optical waveguide device. As shown in the figure, the first optical element 101 includes two second regions, region 107 and region 108, which are located around the first region 103 of the first optical element 101, respectively. The second optical element 102 includes two second regions, region 109 and region 110, which are located around the first region 104 of the second optical element 102, respectively. In this embodiment, the two second regions of the first optical element 101 are not limited to being located diagonally opposite to the waveguide substrate 100, but can also be located on the same side of the waveguide substrate 100; similarly, the two second regions of the second optical element 102 are not limited to being located diagonally opposite to the waveguide substrate 100, but can also be located on the same side of the waveguide substrate 100. The second regions of the first optical element 101 and the second optical element 102 do not overlap or cover each other. Further reference can be made to... Figure 6 , Figure 6 for Figure 5 A schematic diagram of the actual implementation state of the embodiment.

[0051] Optionally, if the first optical element 101 includes a second region, the second region may be surrounded by a first region 103 of the first optical element 101. Alternatively, if the second optical element 102 includes a second region, the second region may be surrounded by a first region 104 of the second optical element 102. See also... Figure 7 , Figure 7 This is a schematic diagram illustrating the arrangement of the second regions of the first optical element and the second optical element in another embodiment of the optical waveguide device. As shown in the figure, the first optical element 101 includes two second regions, namely region five 111 and region six 112, which are respectively surrounded by the first region 103 of the first optical element 101. The second optical element 102 includes a second region, namely region seven 113, which is surrounded by the first region 104 of the second optical element 102.

[0052] Optionally, the first optical element 101 and the second optical element 102 may be located on the same plane in the thickness direction of the waveguide substrate 100 (e.g., Figure 5 and Figure 6 (As shown). A plane in the thickness direction of the waveguide substrate 100 refers to a plane perpendicular to the thickness direction of the waveguide substrate 100. The first optical element 101 includes a second region, and / or the second optical element 102 includes a second region. Figure 6 for Figure 5 Figure 5 The actual implementation state of the embodiment is shown in the figure. In this embodiment, the first optical element 101 and the second optical element 102 are located on the same plane of the waveguide substrate 1, that is, they are superimposed as one unit. Therefore, the first optical element 101 and the second optical element 102 form a unit structure with a two-dimensional periodic arrangement.

[0053] Optionally, the first optical element 101 and the second optical element 102 can be respectively located in different planes in the thickness direction of the waveguide substrate 100. In this case, the first optical element 101 can include a second region, i.e. the first optical element 101 includes a region not covered by the second optical element 102. Alternatively, the second optical element 102 can include a second region, i.e. the second optical element 102 includes a region not covered by the first optical element 101.

[0054] Alternatively, the first optical element 101 includes a region not covered by the second optical element 102, and the second optical element 102 also includes a region not covered by the first optical element 101. In this case, the first optical element 101 and the second optical element 102 can be respectively located in different planes in the thickness direction of the waveguide substrate 100, and the first optical element 101 can include a plurality of second regions, and the second optical element 102 can include a plurality of second regions. The shape, size and number of the second regions of the first optical element 101 can be different from those of the second regions of the second optical element 102.

[0055] It should be further noted that in the above embodiments, the first region 103 of the first optical element 101 or the first region 104 of the second optical element 102 can be configured to at least partially couple the light propagating in the waveguide substrate 100 out of the waveguide substrate 100. Alternatively, the first region 103 of the first optical element 101 or the first region 104 of the second optical element 102 can be configured to diffract the light propagating in the waveguide substrate 100 to deflect at least part of the light in the waveguide substrate 100 in a direction different from the original direction of propagation. Preferably, the first region 103 of the first optical element 101 and the first region 104 of the second optical element 102 are configured to cooperate to expand the light propagating in the waveguide substrate 100 in two dimensions.

[0056] Accordingly, the present embodiment also provides a display device, which includes an image projection device and a light waveguide device. The image projection device is configured to generate light rays, and the light rays are configured to be incident on the light waveguide device. The light waveguide device is the light waveguide device described above.

[0057] In the light waveguide device used in the display device of the present embodiment, the first optical element and the second optical element are disposed on or in the waveguide substrate, and the first region of the first optical element and the first region of the second optical element are overlapped with each other. The first region of the first optical element and the first region of the second optical element are configured to diffract the light propagating in the waveguide substrate to change the propagation form of at least part of the light.

[0058] At least one of the first optical element and the second optical element comprises a second region, the second region being a region without covering the other optical element, the second region causing the light propagating in the waveguide substrate to diffract so that at least part of the light propagates along the waveguide substrate to the first region of the first optical element or the first region of the second optical element, so that the light propagating to the second region is caused to propagate at least partially to the first region of the first optical element or the first region of the second optical element through the second region, thereby reducing the loss of light energy and improving the utilization of light energy.

[0059] The display device of the embodiment can be a near-eye display device, such as a head-mounted virtual reality glasses.

[0060] The above describes in detail the light waveguide device and the display device provided by the present application. The principles and implementation manners of the present application are described by applying specific examples. The above description of the embodiments is only used to help understand the method of the present application and its core idea. It should be pointed out that, for those skilled in the art, without departing from the principles of the present application, the present application can be improved and modified in several ways, and these improvements and modifications also fall within the protection scope of the claims of the present application.

Claims

1. An optical waveguide device, characterized by, The optical waveguide device comprises a waveguide substrate, a first optical element and a second optical element, the first optical element and the second optical element are arranged on the upper surface, the lower surface of the waveguide substrate or in the waveguide substrate, the first region of the first optical element and the first region of the second optical element cover each other, at least one of the first optical element and the second optical element comprises a second region, the second region is a region without covering the other optical element; The first region of the first optical element and the first region of the second optical element make the light propagating in the waveguide substrate diffract to change the propagation form of at least part of the light, and the second region makes the light propagating in the waveguide substrate diffract to propagate at least part of the light along the waveguide substrate to the first region of the first optical element or the first region of the second optical element.

2. The optical waveguide device of claim 1, wherein, The first optical element comprises the second region, and the second region is located on one side of the first region of the first optical element. Alternatively, the second optical element comprises the second region, and the second region is located on one side of the first region of the second optical element.

3. The optical waveguide device of claim 1, wherein, The first optical element comprises the second region, and the second region is surrounded by the first region of the first optical element. Alternatively, the second optical element comprises the second region, and the second region is surrounded by the first region of the second optical element.

4. The optical waveguide device of claim 1, wherein, The first optical element and the second optical element are respectively located on different planes in the thickness direction of the waveguide substrate.

5. The optical waveguide device of claim 1, wherein, The first optical element and the second optical element are located on the same plane in the thickness direction of the waveguide substrate.

6. The optical waveguide device of claim 1, wherein, The first optical element comprises at least one second region, and / or the second optical element comprises at least one second region.

7. The optical waveguide device of any of claims 1-6, wherein, The second region makes the light propagating in the waveguide substrate diffract, makes at least part of the light propagate along one-dimensional direction of the waveguide substrate, makes at least another part of the light propagate along another one-dimensional direction of the waveguide substrate, to realize the propagation of at least part of the light along the waveguide substrate to the first region of the first optical element or the first region of the second optical element.

8. The optical waveguide device of any of claims 1-6, wherein, The first optical element comprises the second region, and the unit structure arrangement period of the first region of the first optical element is consistent with the unit structure arrangement period of the second region of the first optical element. Alternatively, the second optical element comprises the second region, and the unit structure arrangement period of the first region of the second optical element is consistent with the unit structure arrangement period of the second region of the second optical element.

9. The optical waveguide device of claim 1, wherein, The first region of the first optical element and the first region of the second optical element cooperate to make the light propagating in the waveguide substrate expand along two-dimensional direction.

10. A display device, characterized by The optical waveguide device comprises an image projection device and an optical waveguide device, the image projection device is used to generate light rays, and the light rays are incident on the optical waveguide device, and the optical waveguide device is the optical waveguide device according to any one of claims 1-9.

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