Diffraction optical waveguide and near-to-eye display equipment

Abstract

The invention provides a diffraction optical waveguide and a near-to-eye display device, the diffraction optical waveguide comprises a plurality of discrete diffraction coupling-out structures and a plurality of discrete light leakage prevention microstructures, each light leakage prevention microstructure at least corresponds to one diffraction coupling-out structure, and the spatial position of each diffraction coupling-out structure is close to the human eye relative to the light leakage prevention microstructure. Light leakage processing is carried out on the corresponding diffraction coupling-out structures through all the light leakage prevention microstructures, and information leakage is avoided; on the other hand, all the light leakage prevention microstructures are discrete, not overlapped and arranged in different areas in a small area mode, so that the area influencing the ambient light is small, the human eyes can still receive the ambient light through the area outside the light leakage prevention microstructures, namely, the human eyes can receive the ambient light to a large extent, and the light leakage prevention effect is improved. A user can receive ambient light while preventing information leakage as much as possible, the influence on external observation is reduced as much as possible, and the brightness of image light, obtained by human eyes, of an optical machine and the brightness of external ambient light are more adaptive and more balanced.

Description

Technical Field

[0001] The present invention relates to the field of optical technologies, and particularly to a diffractive optical waveguide and a near-eye display device. Background Art

[0002] Augmented Reality (AR) technology is a technology that combines virtual information with the real world. When an AR device is in use, it is necessary to ensure that virtual information can be observed while also ensuring that the real external world can be observed.

[0003] Generally, the display system for displaying virtual information in an AR device usually consists of a display screen and an optical system. The image displayed on the display screen is transmitted to the human eye through the optical system. And in order to avoid blocking the observation of the real world, the image emitted by the display screen is transmitted by adding an optical waveguide. The image emitted by the display screen enters from the coupling-in end of the optical waveguide and exits from the coupling-out end.

[0004] When the image light is transmitted in the diffractive optical waveguide and is incident on the diffractive coupling-out structure, diffraction occurs. The diffraction effect will simultaneously have reflection orders and transmission orders with opposite propagation directions. The diffraction order propagating towards the human eye side will be coupled out from the surface of the diffractive optical waveguide close to the human eye side and enter the human eye, and the diffraction order propagating away from the human eye side will be coupled out from the surface of the diffractive optical waveguide away from the human eye side, resulting in information leakage. Summary of the Invention

[0005] To solve the above problems, the present invention provides a diffractive optical waveguide, which includes a plurality of discrete diffractive coupling-out structures and a plurality of discrete light-leakage prevention microstructures. Each of the light-leakage prevention microstructures corresponds to at least one of the diffractive coupling-out structures. The spatial position of the diffractive coupling-out structure is closer to the human eye than the light-leakage prevention microstructure. Each of the diffractive coupling-out structures includes a plurality of periodically arranged diffraction units.

[0006] Preferably, each of the diffractive coupling-out structures corresponds to one of the light-leakage prevention microstructures, and the orthographic projection of each of the light-leakage prevention microstructures respectively covers the corresponding diffractive coupling-out structure.

[0007] Preferably, the size of the diffractive coupling-out structure is at the micron level or above, and the plurality of diffractive coupling-out structures are arranged in a regular array.

[0008] Preferably, the size of the diffractive coupling-out structure is at the sub-micron level or below, and the plurality of diffractive coupling-out structures are randomly arranged.

[0009] Preferably, the distance between any two of the diffractive coupling-out structures is less than the diameter of the human eye pupil.

[0010] Preferably, the diffractive optical waveguide includes at least one waveguide sheet and at least one protective sheet stacked thereon. The diffractive coupling-out structure is disposed on one side of the waveguide sheet facing the protective sheet, and the light leakage prevention microstructure is disposed on one side of the protective sheet facing the waveguide sheet. The working order of the diffractive coupling-out structure is a reflection order, and the light leakage prevention microstructure is an absorbing structure, a reflecting structure, or an astigmatic structure.

[0011] Preferably, the absorbing structure is a blackened material layer or a light filtering material layer, the reflecting structure is a reflective material layer, and the astigmatic structure is a microlens or a diffractive structure.

[0012] Preferably, the diffractive optical waveguide includes at least one waveguide sheet. The diffractive coupling-out structure is disposed on one surface of the waveguide sheet, and the light leakage prevention microstructure is disposed on the surface of the diffractive coupling-out structure. The light leakage prevention microstructure includes a reflecting structure disposed on the surface of the diffractive coupling-out structure and an absorbing structure disposed on the surface of the reflecting structure.

[0013] Preferably, the diffractive optical waveguide includes at least one waveguide sheet. The waveguide sheet includes opposite first and second sides. The diffractive coupling-out structure is disposed on the first side and operates in a transmission order, and the light leakage prevention microstructure is disposed on the second side. The light leakage prevention microstructure is an absorbing structure or a reflecting structure.

[0014] The present invention also provides a near-eye display device including the above diffractive optical waveguide.

[0015] Compared with the prior art, the present invention has the following technical effects:

[0016] Instead of covering the coupling-out region of the diffractive optical waveguide with diffractive coupling-out structures according to the technical idea of the prior art, the present invention disposes a plurality of discrete diffractive coupling-out structures. Each light leakage prevention microstructure corresponds to at least one diffractive coupling-out structure, and the spatial position of the diffractive coupling-out structure is closer to the human eye relative to the light leakage prevention microstructure. In this way, on the one hand, the discrete arrangement of the diffractive coupling-out structures does not affect the normal imaging of virtual content. On the other hand, by performing light leakage treatment on the diffractive coupling-out structures through the light leakage prevention microstructures, light leakage can be reduced or even eliminated, or the light leakage cannot be normally imaged, thereby alleviating or even avoiding information leakage. On the other hand, the light leakage prevention microstructures are also discrete, non-overlapping, and are arranged in regions and with small areas. Therefore, the influence on ambient light is small, and the human eye can still receive ambient light through the region outside the light leakage prevention microstructures on the diffractive optical waveguide, that is, the human eye can receive ambient light to a large extent, enabling the user to receive ambient light as much as possible while preventing information leakage, minimizing the impact on viewing the real world, and making the brightness of the image light of the optical engine obtained by the human eye more adapted and balanced with the brightness of the ambient light outside. Description of the Drawings

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0018] Figure 1 is a schematic structural diagram of a diffractive optical waveguide provided by the present invention;

[0019] Figure 2 is a schematic structural diagram of another diffractive optical waveguide provided by the present invention;

[0020] Figure 3 is a schematic structural diagram of the diffractive optical waveguide provided in Embodiment 1 of the present invention;

[0021] Figure 4 is a schematic structural diagram of the diffractive optical waveguide provided in Embodiment 2 of the present invention;

[0022] Figure 5 is a schematic structural diagram of the diffractive optical waveguide provided in Embodiment 3 of the present invention;

[0023] Figure 6 is a schematic structural diagram of the diffractive optical waveguide provided in Embodiment 4 of the present invention;

[0024] Figure 7 is a schematic structural diagram of a diffractive optical waveguide provided in Embodiment 5 of the present invention;

[0025] Figure 8 is another schematic structural diagram of the diffractive optical waveguide provided in Embodiment 5 of the present invention. Detailed implementation manners

[0026] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0027] Refer to Figure 1 , the diffractive optical waveguide 1 includes an input region 101 and an output region. A plurality of discrete diffractive output structures 102 are arranged in the output region. The image light rays emitted by the optical machine enter the diffractive optical waveguide 1 from the input region 101 and are output from the diffractive optical waveguide 1 after being diffracted by the diffractive output structures 102.

[0028] Refer to Figure 2, the diffractive optical waveguide 1 further includes a turning region 104 for turning the propagation direction of the image light rays that enter the diffractive optical waveguide 1 through the coupling-in region 101. The size of the turning region 104 is related to the size of the coupling-out region, with the aim of turning the image light rays towards the coupling-out region as much as possible for being coupled out and utilized.

[0029] In the present invention, a plurality of discrete diffractive coupling-out structures 102 are provided in the coupling-out region of the diffractive optical waveguide 1. Each of the diffractive coupling-out structures 102 is independent and non-overlapping, and is arranged in sub-regions with small areas. By setting the size of the independent diffractive coupling-out structures 102 and the gaps between each of the diffractive coupling-out structures 102, it can be ensured that the human eye can receive the image light rays of the complete field of view at any position within the viewing window.

[0030] Furthermore, the sizes of these diffractive coupling-out structures 102 can be the same or different, and the external contour shapes of the diffractive coupling-out structures 102 can be the same or different. If the sizes of the diffractive coupling-out structures 102 are the same and are at the order of hundreds of micrometers or above, then these diffractive coupling-out structures 102 can be arranged in a regular array; when the sizes are at the order of tens of micrometers or below, then these diffractive coupling-out structures 102 need to be randomly arranged to avoid the rainbow patterns generated by interference. The spacing between any two of these diffractive coupling-out structures 102 should be less than the diameter of the human eye's pupil, generally 4 mm, to prevent there being positions within the viewing window where the virtual content imaging cannot be viewed.

[0031] In the present invention, a light leakage prevention microstructure is provided at a position in the diffractive optical waveguide where the spatial position is farther from the human eye compared to the diffractive coupling-out structures, such that the image light rays diffracted by the diffractive coupling-out structures and propagating away from the human eye will pass through the light leakage prevention microstructure before leaking into the real world, thus alleviating or even avoiding information leakage. The present invention places no restrictions on the specific structure of the light leakage prevention microstructure 103. The light leakage prevention microstructure 103 can be an astigmatic structure for disrupting the normal imaging of the leaked image light rays, an absorbing structure for absorbing the leaked image light rays, or a reflecting structure for reflecting the leaked image light rays back towards the human eye direction. On the one hand, each light leakage prevention microstructure 103 performs light leakage processing on the corresponding diffractive coupling-out structure 102 to avoid information leakage. On the other hand, each of the light leakage prevention microstructures 103 is also discrete, non-overlapping, and arranged in sub-regions with small areas. Therefore, the influence on ambient light is small, and the human eye can still receive ambient light through the regions outside the light leakage prevention microstructures 103, that is, the human eye can receive ambient light to a large extent, enabling the user to receive ambient light as much as possible while preventing information leakage, minimizing the impact on the observation of the outside world, and making the brightness of the image light rays of the optical machine obtained by the human eye more compatible and balanced with the brightness of the ambient light.

[0032] Specifically, each light leakage prevention microstructure in the present invention corresponds to at least one diffraction coupling out structure. Implementably, there can be a one-to-one correspondence between the light leakage prevention microstructure and the diffraction coupling out structure, or one light leakage prevention microstructure can correspond to multiple diffraction coupling out structures, or multiple light leakage prevention microstructures can correspond to one diffraction coupling out structure, or one light leakage prevention microstructure can correspond to one diffraction coupling out structure and there are some diffraction coupling out structures without corresponding light leakage prevention microstructures. Herein, the correspondence between the light leakage prevention microstructure and the diffraction coupling out structure means that the projection of the light leakage prevention microstructure on the plane where the diffraction coupling out structure is located at least partially covers the diffraction coupling out structure. The above implementable corresponding settings of the light leakage prevention microstructure and the diffraction coupling out structure can reduce or even eliminate light leakage or make the light leakage unable to be normally imaged, thereby alleviating or even avoiding information leakage.

[0033] Further, when there is a one-to-one correspondence between the light leakage prevention microstructure and the diffraction coupling out structure, or one light leakage prevention microstructure corresponds to multiple diffraction coupling out structures, and the projection of the light leakage prevention microstructure on the plane where the diffraction coupling out structure is located can completely cover the corresponding diffraction coupling out structure, all the image light rays diffracted by the diffraction coupling out structure and propagating away from the human eye can be affected, thereby eliminating light leakage or making the light leakage unable to be normally imaged, and further being able to avoid information leakage.

[0034] Specifically, in the present invention, the spatial position of the diffraction coupling out structure is closer to the human eye relative to the light leakage prevention microstructure. Implementably, both the light leakage prevention microstructure and the diffraction coupling out structure are arranged on the waveguide sheet. The diffraction coupling out structure is arranged on the side of the waveguide sheet close to the human eye, and the light leakage prevention microstructure is arranged on the side of the waveguide sheet away from the human eye, or the light leakage prevention microstructure is arranged on the diffraction coupling out structure and on the side of the diffraction coupling out structure away from the human eye. The light leakage prevention microstructure can also be arranged on the protective sheet that is farther from the human eye than the waveguide sheet. In this way, the image light rays diffracted by the diffraction coupling out structure and propagating away from the human eye will pass through the light leakage prevention microstructure before leaking into the real world. The light leakage prevention microstructure acts on this part of the image light rays, reducing or even blocking them from entering the real world, or destroying their normal imaging in the real world, alleviating or even avoiding information leakage.

[0035] Specifically, each diffraction coupling out structure in the present invention includes a number of periodically arranged diffraction units. The diffraction unit can specifically be a grating unit, and the grating unit can be a one-dimensional grating unit or a two-dimensional grating unit. The tooth shape of the grating unit is not limited and can be a straight tooth or an inclined tooth. The cross-sectional shape of the grating unit is also not limited and can be an ellipse or a rhombus, etc.

[0036] The following uses several specific embodiments of the light leakage prevention microstructure 103 to describe the diffractive optical waveguide of the present invention in detail.

[0037] Embodiment 1

[0038] Please refer toFigure 3 , this embodiment provides a diffractive optical waveguide, which includes a stack of a waveguide sheet 105 and a protective sheet 106. A plurality of discretely distributed diffractive coupling-out structures 102 are arranged on the side of the waveguide sheet 105 facing the protective sheet 106, and a plurality of discrete light-leakage prevention microstructures 103 are arranged on the side of the protective sheet 106 facing the waveguide sheet 105. The light-leakage prevention microstructures 103 are arranged in one-to-one correspondence with the diffractive coupling-out structures 102, and the orthographic projection of each light-leakage prevention microstructure 103 respectively covers the corresponding diffractive coupling-out structure 102.

[0039] In this embodiment, the working order of the diffractive coupling-out structure 102 is the reflection order, and the leakage order is the transmission order. The light-leakage prevention microstructure 103 can be implemented as an astigmatic structure, such as a microlens or a diffractive structure, etc. Its function is to normally image the image light rays that damage the leakage order, so that the actual image content cannot be observed from the outside.

[0040] Since the astigmatic structure acts on the image light rays and the ambient light rays synchronously, while destroying the normal imaging of the leakage image light rays, it also destroys the normal imaging of the ambient light rays at its location. However, since the astigmatic structure is set in a sub-region and small area, the impact on the ambient light is within an acceptable range, and it can prevent information leakage as much as possible without causing a great impact on the user's reception of the ambient light, making the brightness of the image light rays of the optical machine obtained by the human eye more adaptable and balanced with the brightness of the ambient light in the outside world.

[0041] In other embodiments, there can be more waveguide sheets, such as two or three; the protective sheet can be two.

[0042] Embodiment 2

[0043] Please refer to Figure 4 , this embodiment provides a diffractive optical waveguide, which includes a stack of a waveguide sheet 105 and a protective sheet 106. A plurality of discretely distributed diffractive coupling-out structures 102 are arranged on the side of the waveguide sheet 105 facing the protective sheet 106, and a plurality of discrete light-leakage prevention microstructures 103' are arranged on the side of the protective sheet 106 facing the waveguide sheet 105. The light-leakage prevention microstructures 103' are arranged in one-to-one correspondence with the diffractive coupling-out structures 102, and the orthographic projection of each light-leakage prevention microstructure 103' respectively covers the corresponding diffractive coupling-out structure 102.

[0044] In this embodiment, the working order of the diffractive coupling-out structure 102 is the reflection order, and the leakage order is the transmission order. The light-leakage prevention microstructure 103' is implemented as an absorbing structure, which is used to absorb the image light rays of the leakage order and prevent the image light rays from propagating away from the human eye and entering the real world to cause information leakage.

[0045] Optionally, the light-absorbing structure can be a blackened material layer. The blackened material layer can absorb light in the entire wavelength range, and its effects on image light and ambient light are synchronous. However, since the light-absorbing structure is arranged in regions and small areas, the impact on ambient light is within an acceptable range, and it can prevent information leakage as much as possible while having little impact on the user's reception of ambient light. The light-absorbing structure can also be a light-filtering material layer, which only filters the wavelength band corresponding to the image light, so that ambient light in other wavelength bands can still enter the human eye, minimizing the impact on the viewing of the real world.

[0046] Embodiment 3

[0047] Please refer to Figure 5 , this embodiment provides a diffractive optical waveguide, including a stacked waveguide sheet 105 and a protective sheet 106. On the side of the waveguide sheet 105 facing the protective sheet 106, a plurality of discretely distributed diffractive coupling-out structures 102 are provided. On the side of the protective sheet 106 facing the waveguide sheet 105, a plurality of discrete light-leakage prevention microstructures 103” are provided. The light-leakage prevention microstructures 103” are arranged in one-to-one correspondence with the diffractive coupling-out structures 102, and the orthographic projection of each light-leakage prevention microstructure 103 respectively covers the corresponding diffractive coupling-out structure 102.

[0048] In this embodiment, the working order of the diffractive coupling-out structure 102 is the reflection order, and the leakage order is the transmission order. The light-leakage prevention microstructure 103” is implemented as a reflection structure, such as a reflective material layer, whose function is to reflect the image light of the leakage order back towards the human eye direction. The image light reflected back into the waveguide can be reused, thus improving the light energy utilization rate while preventing information leakage.

[0049] Embodiment 4

[0050] Please refer to Figure 6 , this embodiment provides a diffractive optical waveguide, including a waveguide sheet 105. On one side surface of the waveguide sheet 105, a plurality of discrete diffractive coupling-out structures 102 are provided. On the surface of each diffractive coupling-out structure 102, a light-leakage prevention microstructure 103”' is provided. The light-leakage prevention microstructure 103”' includes a reflection structure 1031 provided on the surface of the diffractive coupling-out structure 102 and a light-absorbing structure 1032 provided on the surface of the reflection structure 1031. The reflection structure 1031 completely covers the diffractive coupling-out structure 102, and the light-absorbing structure 1032 completely covers the reflection structure 1031.

[0051] In this embodiment, the working order of the diffractive coupling-out structure 102 is the reflection order, and the leakage order is the transmission order. The reflection structure 1031, such as a reflective material layer, can increase the diffraction efficiency of the reflection order and reduce the diffraction efficiency of the leakage order, preventing information leakage while increasing the brightness of the image displayed by the waveguide.

[0052] The light-absorbing structure can be a blackened material layer. The blackened material layer can absorb light in the entire wavelength band, and its effects on image light and ambient light are synchronous. However, since the light-absorbing structure is set in regions and with small areas, its impact on ambient light is within an acceptable range, and it can prevent information leakage as much as possible without significantly affecting the user's reception of ambient light. The light-absorbing structure can also be a light-filtering material layer. The light-filtering material layer only filters out the wavelength band corresponding to the image light, so that ambient light in other wavelength bands can still enter the human eye, and it can minimize the impact on viewing the real world. In this embodiment, an additional light-absorbing structure 1032 is provided on the reflection structure 1031 to absorb the image light of the leakage level.

[0053] Further, a reflection structure 1012 is also provided on the diffraction coupling structure 1011 coupled into the region 101, and the working level is also the reflection level. At this time, both the diffraction coupling structure 1011 and the diffraction coupling-out structure 102 are protected by the reflection structure, and no additional protective sheet needs to be added, which can reduce the thickness of the diffractive optical waveguide.

[0054] Embodiment 5

[0055] Please refer to Figure 7 and Figure 8 , this embodiment provides a diffractive optical waveguide, including a waveguide sheet 105 and a protective sheet. The waveguide sheet 105 includes opposite first and second sides. A plurality of discrete diffraction coupling-out structures 102 are provided on the first side of the waveguide sheet 105, and the working level of the diffraction coupling-out structure 102 is the transmission level, and the leakage level is the reflection level. A plurality of discrete light-leakage prevention microstructures 103”” are provided on the second side of the waveguide sheet 105. The light-leakage prevention microstructures 103”” are arranged in one-to-one correspondence with the diffraction coupling-out structures 102, and the orthographic projection of each light-leakage prevention microstructure 103 respectively covers the corresponding diffraction coupling-out structure 102.

[0056] Please refer to Figure 7 , the light-leakage prevention microstructure 103”” is a light-absorbing structure. Optionally, the light-absorbing structure can be a blackened material layer. The blackened material layer can absorb light in the entire wavelength band, and its effects on image light and ambient light are synchronous. However, since the light-absorbing structure is set in regions and with small areas, its impact on ambient light is within an acceptable range, and it can prevent information leakage as much as possible without significantly affecting the user's reception of ambient light. The light-absorbing structure can also be a light-filtering material layer. The light-filtering material layer only filters out the wavelength band corresponding to the image light, so that ambient light in other wavelength bands can still enter the human eye, and it can minimize the impact on viewing the real world.

[0057] Please refer to Figure 8The light leakage prevention microstructure 103 is a reflection structure. Optionally, the reflection structure can be a reflective material layer, which functions to reflect the image light of the leakage level back towards the human eye direction. The image light reflected back into the waveguide can be reused, thus improving the light energy utilization rate while preventing information leakage.

[0058] It should be noted that when the light leakage prevention microstructure includes an absorbing structure and / or a reflection structure in the foregoing embodiments, it can not only alleviate or even solve the light leakage problem, but also the external ambient light will be absorbed when incident on the absorbing structure and / or reflected when incident on the reflection structure and thus cannot be incident on the diffraction coupling out structure, thereby avoiding the rainbow pattern formed by the diffraction of the external ambient light by the diffraction coupling out structure. Moreover, when the diffractive optical waveguide further includes a turning region, the diffractive turning structure in the turning region should also correspondingly have an absorbing structure and / or a reflection structure, thereby avoiding the rainbow pattern formed by the diffraction of the external ambient light by the diffractive turning structure.

[0059] According to one aspect of the present invention, there is also provided a near-eye display device, which includes the diffractive optical waveguide as described in any one of the foregoing.

[0060] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A diffractive optical waveguide, characterized in that: It includes multiple discrete diffraction outcoupling structures and multiple discrete anti-light leakage microstructures, each of the anti-light leakage microstructures corresponds to at least one diffraction outcoupling structure, the spatial position of the diffraction outcoupling structure is close to the human eye relative to the anti-light leakage microstructure, and each of the diffraction outcoupling structures includes a plurality of periodically arranged diffraction units.

2. The diffractive optical waveguide according to claim 1, characterized in that: Each of the diffraction outcoupling structures corresponds to one of the light leakage prevention microstructures, and the orthographic projection of each of the light leakage prevention microstructures covers the corresponding diffraction outcoupling structure.

3. The diffractive optical waveguide according to claim 1, characterized in that: The size of the diffraction outcoupling structure is at or above the order of hundreds of microns, and a plurality of the diffraction outcoupling structures are arranged in a regular array.

4. The diffractive optical waveguide according to claim 1, characterized in that: The size of the diffraction outcoupling structure is at or below ten micrometers, and a plurality of the diffraction outcoupling structures are randomly arranged.

5. The diffractive optical waveguide according to claim 1, characterized in that: The distance between any two of the diffractive outcoupling structures is smaller than the diameter of the pupil of a human eye.

6. The diffractive optical waveguide according to any one of claims 1 to 5, characterized in that: The diffraction optical waveguide includes at least one stacked waveguide plate and at least one protective plate, the diffraction outcoupling structure is arranged on the side of the waveguide plate facing the protective plate, the anti-light leakage microstructure is arranged on the side of the protective plate facing the waveguide plate, the working order of the diffraction outcoupling structure is the reflection order, and the anti-light leakage microstructure is a light absorption structure, a reflection structure or an astigmatism structure.

7. The diffractive optical waveguide according to claim 6, characterized in that: The light absorbing structure is a black coating material layer or a light filtering material layer, the reflecting structure is a reflecting material layer, and the astigmatism structure is a micro lens or a diffraction structure.

8. The diffractive optical waveguide according to any one of claims 1 to 5, characterized in that: The diffraction optical waveguide includes at least one waveguide plate, the diffraction outcoupling structure is arranged on a side surface of the waveguide plate, the anti-light leakage microstructure is arranged on the surface of the diffraction outcoupling structure, and the anti-light leakage microstructure includes a reflective structure arranged on the surface of the diffraction outcoupling structure and a light absorbing structure arranged on the surface of the reflective structure.

9. The diffractive optical waveguide according to any one of claims 1 to 5, characterized in that: The diffraction optical waveguide includes at least one waveguide plate, the waveguide plate includes a first side and a second side opposite to each other, the diffraction outcoupling structure is arranged on the first side and works in the transmission order, the anti-light leakage microstructure is arranged on the second side, and the anti-light leakage microstructure is a light absorbing structure or a reflective structure.

10. A near-eye display device, characterized in that: A diffractive optical waveguide comprising any one of claims 1 to 9.

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