Light leakage prevention optical waveguide display device and near-to-eye display equipment with same

Abstract

The invention discloses an optical waveguide display device and near-eye display equipment, the optical waveguide display device comprises a first diffraction optical waveguide and a second diffraction optical waveguide which are respectively used for coupling in first input light and second input light and carrying out pupil expansion and coupling out on the first input light and the second input light to realize image display, and the maximum inclination angle of the first input light relative to the normal of the surface of the first diffraction optical waveguide is theta0; an optical film layer is formed on the surface, facing the second diffractive optical waveguide, of the first diffractive optical waveguide, and the optical film layer is constructed to have the average reflectivity of light with the incident angle smaller than a first threshold angle theta1 within the wavelength range of the first input light as R1; the average reflectivity of light with the incident angle larger than the second threshold angle theta2 and smaller than the total reflection critical angle is R2, theta2 > = theta1 > = theta0, 2% < = R1 < = 15%, and 40% < = R2 < = 90%. Through the optical film layer, unexpected light leakage from the first diffraction optical waveguide to the second diffraction optical waveguide can be effectively blocked under the condition that the light effect of image display is not obviously influenced.

Description

Technical Field

[0001] The present invention relates to display technology based on diffractive optical waveguides; specifically, it relates to a light-leakage-proof optical waveguide display device and a near-eye display device having the same. Background Art

[0002] The display technology based on diffractive optical waveguides is one of the mainstream solutions for realizing AR display currently. Among them, waveguide gratings are provided on a waveguide substrate, and the waveguide gratings include an input grating and an output grating. The input grating receives the input light carrying image information from an optical engine and couples it into the waveguide substrate; the output grating propagates and expands the light carrying image information while coupling the light out of the waveguide substrate to form an output light field. The eye receives the light of the output light field, so that for example, the image carried by the incident light can be observed.

[0003] In order to achieve full-color display, a dual-waveguide scheme has been proposed, as Figure 1 shown, in which two diffractive optical waveguides w1 and w2 stacked on top of each other are used to cover a full-color spectral range of about 200 nm from, for example, blue light to red light. These two diffractive optical waveguides w1 and w2 each include a waveguide substrate and input gratings 1, 1' and output gratings 2, 2' formed on the waveguide substrate, and are designed to cover visible light with shorter wavelengths (such as "blue-green light") and visible light with longer wavelengths (such as "red light" or "red-yellow light") respectively. In such a design, since different grating periods can be adopted for different wavelength ranges in the two diffractive optical waveguides, the requirement for the material refractive index of each waveguide substrate can be effectively reduced.

[0004] However, the above dual-waveguide scheme is not without deficiencies. In particular, in addition to the normal light used for display (the light ray a shown by the solid line in Figure 1 ) being coupled and propagated between the two diffractive optical waveguides, there is also an undesirable "light leakage" situation between the two diffractive optical waveguides (the light ray b shown by the dashed line in Figure 1 ), resulting in colored ghost images in the image finally projected onto the eyebox EB and presented to the human eye, which has an adverse impact on the display quality. Summary of the Invention

[0005] The object of the present invention is to provide a light-leakage-proof optical waveguide display device and a near-eye display device having the same, which at least partially overcome the problems in the prior art.

[0006] According to one aspect of the present invention, there is provided a light-leakage-proof optical waveguide display device, including a first diffractive optical waveguide and a second diffractive optical waveguide stacked in parallel with each other, which are respectively used to couple in the first input light and the second input light carrying image information and perform pupil expansion and coupling out on them to realize image display, wherein:

[0007] The first diffractive optical waveguide includes a first waveguide substrate, a first coupling grating, and a first output grating disposed on the first waveguide substrate. The wavelength of the first input light is within a first wavelength range, and the maximum tilt angle of the first input light with respect to the normal of the surface of the first diffractive optical waveguide is θ. 0 ; and

[0008] The first diffractive optical waveguide has a first surface facing the second diffractive optical waveguide, and an optical film layer is formed on the first surface. The optical film layer is configured such that, within the first wavelength range, for light with an incident angle less than a first threshold angle θ 1 , the average reflectivity of the light is R 1 , and for light with an incident angle greater than a second threshold angle θ 2 and less than the critical angle of total reflection, the average reflectivity of the light is R 2 , θ 2 ≥θ 1 ≥θ 0 , 2% ≤ R 1 ≤ 15%, and 40% ≤ R 2 ≤ 90%.

[0009] Advantageously, 5% ≤ R 1 ≤ 10%, and 60% ≤ R 2 ≤ 80%.

[0010] Advantageously, the first threshold angle θ 1 and the second threshold angle θ 2 satisfy θ 2 - θ 1 ≤ 20°.

[0011] In some embodiments where the first output grating diffracts the light propagating therein to generate diffracted light with diffraction orders of ±2, advantageously, the minimum included angle formed by the diffracted light with diffraction orders of ±2 with respect to the normal is

[0012] In some embodiments where the first output grating is configured to couple out the light propagating therein from the first waveguide substrate through +1 - order diffraction to achieve image display, advantageously, the minimum included angle formed by the - 2 - order diffracted light generated by the first output grating when diffracting the light propagating therein with respect to the normal is And the optical film layer is configured to satisfy

[0013] In some embodiments, the first input light has an angular range [±H1, ±V1] with respect to its center line, and the center line has a deflection angle [H2, V2] with respect to the normal line, where H1 and H2 are angles in a first plane passing through the normal line, and V1 and V2 are angles in a second plane passing through the normal line and perpendicular to the first plane, θ 1 > θ 0 ’, where:

[0014]

[0015] In some embodiments, the wavelength of the second input light is within a second wavelength range, where the first wavelength range covers shorter wavelengths, and the second wavelength range covers longer wavelengths. In such embodiments, the width of the first wavelength range may be in the range of 100 - 150 nm, where the peak wavelength may be in the range of 470 - 510 nm; and the width of the second wavelength range may be in the range of 100 - 150 nm, where the peak wavelength may be in the range of 570 - 610 nm. Advantageously, the first input light is blue light and / or green light, and the second input light is red light.

[0016] In some embodiments, the wavelength of the second input light is within a second wavelength range, the first wavelength range and the second wavelength range at least partially overlap, and lights of the same wavelength in the first input light and the second input light have different field-of-view angle ranges.

[0017] Advantageously, the first output grating is a reflective output grating and is formed on a second surface of the first diffractive optical waveguide opposite to the first surface.

[0018] Advantageously, the second diffractive optical waveguide includes a second waveguide substrate and a second input grating and a second output grating disposed on the second waveguide substrate. The second output grating is aligned with the first output grating along the direction of the normal line, and the projection of the optical film layer along the normal line direction at least partially overlaps with the first output grating.

[0019] In some embodiments, the optical waveguide display device further includes a third diffractive optical waveguide, which is stacked in parallel with the first diffractive optical waveguide and the second diffractive optical waveguide.

[0020] According to another aspect of the present invention, there is also provided a near-eye display device, which includes a lens and a frame for holding the lens close to the eye, and the lens includes the optical waveguide display device as described above.

[0021] Advantageously, the display device is an augmented reality display device or a virtual reality display device.

[0022] In the optical waveguide display device according to an embodiment of the present invention, by providing an optical film layer on a first surface of the first diffractive optical waveguide facing the second diffractive optical waveguide, and configuring the optical film layer to have specific reflectivity characteristics with respect to different incident angle ranges, it effectively blocks the unwanted light leakage from the first diffractive optical waveguide to the second diffractive optical waveguide without significantly affecting the light effect of the image display, suppresses the possible "ghosting" phenomenon caused thereby, and improves the display quality. Description of the Drawings

[0023] Other features, objects, and advantages of the present invention will become more apparent by reading the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0024] Figure 1 A schematic side view of a dual waveguide display device of the prior art;

[0025] Figure 2 A schematic side view of an optical waveguide display device according to an embodiment of the present invention;

[0026] Figure 3 A schematic diagram of multiple incident angle ranges with different reflection characteristics of an optical film layer that can be used in an optical waveguide display device according to an embodiment of the present invention;

[0027] Figure 4 A schematic plan view of an example of a first diffractive optical waveguide;

[0028] Figure 5 Schematically shows an example of an optical waveguide display device, in which the central axis of the input light of the incident optical waveguide display device has a deflection angle with respect to the normal of the diffractive optical waveguide surface;

[0029] Figure 6 Schematically illustrates the angular range of the input light of the incident optical waveguide display device;

[0030] Figure 7 A wave vector space diagram of the first diffractive optical waveguide of the optical waveguide display device;

[0031] Figure 8 A wave vector space diagram of the second diffractive optical waveguide of the optical waveguide display device;

[0032] Figure 9 A schematic plan view of another example of the optical waveguide display device;

[0033] Figure 10 Schematically shows Figure 9 The different field of view angle ranges of the light of the same wavelength in the first wavelength range and the second wavelength range used in the shown optical waveguide display device;

[0034] Figure 11 Schematic side view of another example of an optical waveguide display device. Detailed implementation mode

[0035] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the related invention, rather than limiting the invention. For the sake of description, only the parts related to the invention are shown in the drawings. It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments can be combined with each other.

[0036] Figure 2 An example of a light leakage prevention optical waveguide display device according to an embodiment of the present invention is shown. As Figure 2 shown, the optical waveguide display device 100 includes a first diffractive optical waveguide 10 and a second diffractive optical waveguide 20 that are stacked parallel to each other. The first diffractive optical waveguide 10 is used to couple in the first input light L1 carrying image information, expand its pupil, and couple it out, and the second diffractive optical waveguide 20 is used to couple in the second input light L2 carrying image information, expand its pupil, and couple it out, so as to realize image display as a whole.

[0037] As Figure 2 shown, the first diffractive optical waveguide 10 includes a first waveguide substrate 11 and a first coupling grating 12 and a first output grating 13 provided on the first waveguide substrate 11. According to an embodiment of the present invention, the first diffractive optical waveguide 10 has a first surface 10a facing the second diffractive optical waveguide 20, and an optical film layer 14 is formed on the first surface 10a.

[0038] The optical film layer 14 of the optical waveguide display device according to an embodiment of the present invention is configured to have different reflection characteristics in different incident angle intervals, and is used to prevent unexpected "light leakage" from the first diffractive optical waveguide 10 to the second diffractive optical waveguide 20, thereby suppressing the ghosting phenomenon caused by the "light leakage". Specifically, as Figure 3 shown, the optical film layer 14 is configured such that within the wavelength range of the first input light L1 (i.e., the first wavelength range), for light incident on the optical film layer 14 with an incident angle less than the first threshold angle θ 1 has a first average reflectivity R 1 , for light with an incident angle greater than the second threshold angle θ 2 and less than the total reflection critical angle θ c has a second average reflectivity of R 2 , and satisfies θ 2 ≥θ 1 ≥θ 0 , 2% ≤ R 1 ≤ 15%, and 40% ≤ R 2 ≤ 90%, where θ 0The maximum tilt angle of the first input light L1 with respect to the normal of the surface of the first diffractive optical waveguide 10 ( Figure 2 as shown in 10b).

[0039] The light for image display that is coupled into, pupil-expanded, and coupled out via the diffractive optical waveguide will retain the original field of view angle of the input light carrying image information input into the diffractive optical waveguide. Therefore, the optical film layer 14 is configured to have a low reflectivity for light incident thereon within an incident angle range of 0 to θ 1 (the first average reflectivity satisfies 2% ≤ R 1 ≤ 15%), which is beneficial to ensuring the efficiency of coupling out the light for image display from the first diffractive optical waveguide 10.

[0040] At the same time, the optical film layer 14 is configured to have a high reflectivity for light within an incident angle range of θ 2 to θ c (the second average reflectivity satisfies 40% ≤ R 2 ≤ 90%), which can help prevent the light in this part from exiting the first diffractive optical waveguide 10, thereby suppressing the ghosting visible to the human eye caused by the light in this part being projected into the window EB area via the second diffractive optical waveguide 20.

[0041] In some embodiments, the first threshold angle θ 1 and the second threshold angle θ 2 can be selected such that θ 2 - θ 1 ≤ 20°. Preferably, θ 2 - θ 1 ≤ 10°.

[0042] To further reduce the impact on the coupling-out efficiency of the light for image display and more effectively suppress the unwanted "light leakage", preferably, the first average reflectivity satisfies R 1 ≤ 10%, and the second average reflectivity R 2 ≥ 60%. At the same time, preferably, R 1 ≥ 5%, and R 2 ≤ 80%. This is because the inventors found that if the first average reflectivity is too low and / or the second average reflectivity is too high, the fluctuations in the reflectivity of the optical film layer 14 for different wavelengths are too large.

[0043] The images usually displayed have a rectangular shape. This corresponds to the field of view angle [±h, ±v] of the light for image display. At the same time, the light engine is often configured to project the input light obliquely with respect to the waveguide display device. Considering the above situation, the following is referred to Figure 5 and Figure 6An example of the light guide display device 100, namely, the light guide display device 100A is introduced. In this example, Figure 5 As shown, the center line of the first input light L1 projected by the optical machine LE has a deflection angle [H2, V2] relative to the normal line of the surface of the first diffractive optical waveguide 10; Figure 6 As shown, the first input light L1 has an angular range of [±H1, ±V1] relative to its center line, where H1 and H2 are first planes passing through the normal line (e.g., passing through the normal line and parallel to Figure 6 V1 and V2 are angles in a second plane passing through the normal and perpendicular to the first plane (e.g., passing through the normal and parallel to the Figure 6 The angle within the plane of the V axis shown in .

[0044] In this example, the optical film layer 14 is configured such that the first threshold angle satisfies θ 1 >θ 0 ',in:

[0045]

[0046] Return to reference Figure 2 In some examples of the optical waveguide display device according to an embodiment of the present invention, preferably, the first outcoupling grating 13 is a reflective outcoupling grating and is formed on a second surface 10b of the first diffraction optical waveguide 10 opposite to the first surface 10a. Figure 4 1 is a plan view of an example of a first diffractive optical waveguide 10 , in which a first outcoupling grating 13 and an optical film layer 14 formed on different surfaces of the first diffractive optical waveguide 10 are respectively shown by solid lines and dotted lines.

[0047] Advantageously, the projection of the optical film layer 14 along the normal direction of the surface of the first diffractive optical waveguide 10 at least partially overlaps with the first outcoupling grating 13. Figure 4 As shown, the projection completely covers the area of ​​the first outcoupling grating 13 .

[0048] exist Figure 2 and Figure 4 In the example shown, the first coupling grating 12 is shown to be formed on the same surface as the first coupling grating 13, but it should be understood that this is merely exemplary and not limiting. In other examples, the first coupling grating 12 and the first coupling grating 13 can be formed on different surfaces.

[0049] In addition, if Figure 2As shown, the second diffractive optical waveguide 20 may include a second waveguide substrate 21 and a second coupling-in grating 22 and a second coupling-out grating 23 disposed on the second waveguide substrate 21. Preferably, the second coupling-out grating 23 is aligned with the first coupling-out grating 13 along the direction of the normal to the surfaces of the first and second diffractive optical waveguides 10, 20. The coverage of the optical film layer 14 may be further determined in combination with its position relative to the second coupling-out grating 23. For example, the projection of the optical film layer 14 along the above-mentioned normal may be arranged to completely cover the area of ​​the second coupling-out grating 23.

[0050] The wavelength of the second input light L2 is within the second wavelength range. Preferably, the first wavelength range covers shorter wavelengths, while the second wavelength range covers longer wavelengths. For example, the first input light may be blue light and / or green light, and the second input light may be red light or red light.

[0051] Preferably, the width of the first wavelength range is in the range of 100-150 nm, with a median wavelength in the range of 470-510 nm; and the width of the second wavelength range is in the range of 100-150 nm, with a median wavelength in the range of 570-610 nm. For example, in some applications, the first wavelength range may be 440 nm-540 nm, and the second wavelength range may be 540 nm-640 nm. In other applications, the first wavelength range may be 440 nm-570 nm, and the second wavelength range may be 500 nm-650 nm.

[0052] In the preferred embodiment of the present invention, it is particularly considered to prevent the first outcoupling grating 13 from diffracting the light propagating therein and generating diffraction light of ±2 orders from emitting from the first diffraction optical waveguide 10 to the second diffraction optical waveguide 20, so the optical film layer 14 is constructed to have a second threshold angle in It is the minimum angle formed by the diffracted light of ±2nd order with respect to the normal line of the surface of the diffraction light waveguide 10 , 20 .

[0053] Alternatively, in applications where the first outcoupling grating 13 is configured to couple light propagating therein out of the first waveguide substrate 11 by +1 order diffraction to achieve image display, the optical film layer 14 may be configured to satisfy in The minimum angle formed by the -2nd order diffracted light generated by the first outcoupling grating due to the diffraction of the light propagating into it with respect to the normal line.

[0054] Diffraction optical waveguides usually use 0th and ±1st order diffraction for propagation, pupil expansion and outcoupling. In addition, ±2nd order diffraction light, especially -2nd order diffraction light, which is difficult to ignore, may be generated. After being coupled into the second diffraction optical waveguide 20, the ±2nd order diffraction light (especially -2nd order diffraction light) generated by the first outcoupling grating 13 of the first diffraction optical waveguide 10 will produce an image that is offset from the expected image (the viewing angle is changed) under the diffraction effect of the second outcoupling grating 23, which is an important reason for the existence of "ghost images" in the optical waveguide display device.

[0055] For ease of understanding, Figure 7 and Figure 8 The wave vector space diagrams of the first diffractive optical waveguide 10 and the second diffractive optical waveguide 20 in the optical waveguide display device 100 are schematically shown respectively. Figure 7 and Figure 8 In the wave vector space shown, B 1 , B 1 ' respectively represent the first wave vector boundary formed by satisfying the total internal reflection condition in the first and second diffractive optical waveguides 10 and 20, and the first wave vector boundary B 1 , B 1 'Can be normalized to a circle with a radius of 1; B 2 , B 2 ' respectively represent the second wave vector boundary corresponding to the maximum wave vector that can be transmitted in the first and second diffractive optical waveguides 10 and 20, and the second wave vector boundary B 2 , B 2 ' is determined by the refractive index of the waveguide substrates 11 and 21 respectively. 1 , B 1 ' and the second wave vector boundary B 2 , B 2 ', light can be transmitted in the diffraction waveguide. If the beam wave vector is at the first wave vector boundary B 1 , B 1 ', light will leak out from the waveguide substrate.

[0056] Figure 7 In the wave vector space diagram of the first diffraction optical waveguide 10 shown in FIG. 1 , F represents the field angle range of the input light L1 incident on the first coupling-in grating 12, ①, ②, ③, ④, and ⑤ respectively represent that the first coupling-out grating 13 diffracts the light propagating therein with +1 order in three different grating vector directions, and these diffractions expand the pupil and couple out the light, and ⑥ represents that the first coupling-out grating 13 also diffracts the light propagating therein with -2 order, and at least a part of the light generated by the diffraction enters the first wave vector boundary B. 1 , thereby leaking out from the first diffractive optical waveguide 10, entering and coupling into the second diffractive optical waveguide 20. In the second diffractive optical waveguide 20, asFigure 8 As shown in the wave vector space diagram, the leaked light is diffracted by the second out-coupling grating 23 (see Figure 8 The light is coupled out from the second diffractive optical waveguide 20 and forms a “ghost” with a viewing angle of F′.

[0057] In a preferred embodiment of the present invention, the second threshold angle is set to or The optical film layer 14 is combined with the second threshold angle θ for the incident angle greater than 2 And less than the critical angle of total reflection θ c The light has a larger average reflectivity R 2 (40%≤R 2 ≤90%, preferably R 2 ≥60%), the optical film layer 14 can effectively prevent the ±2nd order diffraction light (especially -2nd order diffraction light) generated by the first outcoupling grating 13 from leaking from the first diffraction light waveguide 10 and generating "ghost images".

[0058] In the optical waveguide device according to the embodiment of the present invention, the first wavelength range may at least partially overlap with the second wavelength range, and light of the same wavelength in the first input light and the second input light may have different viewing angle ranges. Figure 9 An example of such a light waveguide display device, namely a light waveguide display device 100B, is schematically shown; Figure 10 The optical waveguide display device 100B schematically shows different viewing angle ranges of light of the same wavelength in the first wavelength range and the second wavelength range. Figure 2 The optical waveguide display device 100 shown in FIG. 1 is substantially the same in structure, except that: Figure 9 As shown, the first coupling grating 12 of the first diffractive optical waveguide 10 of the optical waveguide display device 100B includes a blue light coupling grating 12a and a green light coupling grating 12b, and the second coupling grating 22 of the second diffractive optical waveguide 20 includes a green light coupling grating 22a and a red light coupling grating 22b. The green light coupling grating 12b and the green light coupling grating 22a can be aligned in a direction perpendicular to the diffractive optical waveguides 10 and 20. Since the first coupling grating 12 and the second coupling grating 22 have different grating periods, the first viewing angle range F of the optical waveguide display device 100B projected by the optical machine is 1 The green light of the first diffraction waveguide 10 is coupled into the first diffraction waveguide 10 via the green light coupling grating 12b, and the second viewing angle range F 2 The green light is coupled into the second diffractive optical waveguide 20 via the green light coupling grating 22a, so that the entire target field of view angle range F can be achieved through the first and second diffractive optical waveguides 10 and 20. 0When designing and manufacturing the optical film layer 14, for green light, only the first viewing angle range F1 can be considered to determine the maximum tilt angle of the green light input light relative to the normal line of the surface of the first diffractive light waveguide 10 as θ. 0 .

[0059] although Figure 2 , Figure 5 and Figure 9 In the example shown, the light guide display device only includes the first and second diffractive light guides, but it should be understood that the present invention is not limited in this respect. That is, the light guide display device according to the embodiment of the present invention may include three or more diffractive light guides stacked in parallel with each other. For example, Figure 11 Another example of an optical waveguide display device is shown. Figure 11 As shown, in addition to the first diffraction light waveguide 10 and the second diffraction light waveguide 20, the light waveguide display device 100C also includes a third diffraction light waveguide 30 stacked in parallel with the first diffraction light waveguide and the second diffraction light waveguide. The third diffraction light waveguide 30 may include a third waveguide substrate 31 and a third coupling-in grating 32 and a third coupling-out grating 33 disposed on the third waveguide substrate 31. An optical film layer 24 may be formed on the third surface 20a of the second diffraction light waveguide 20 facing the third diffraction light waveguide 30, and the optical film layer 24 is constructed similarly to the optical film layer 14. Specifically, the optical film layer 24 is constructed as follows: within the second wavelength range, for an incident angle less than a third threshold angle θ 3 The light has a third average reflectivity R 3 , for incident angles greater than the fourth threshold angle θ 4 The light whose angle is less than the critical angle of total reflection has a fourth average reflectivity of R 4 ,θ 4 ≥θ 3 ≥θ 0 , 2% ≤ R 1 ≤15%, and 40%≤R 4 ≤90%.

[0060] The optical waveguide display device 100C may have the above reference Figures 2 to 10 The same and similar features introduced above will not be repeated here.

[0061] The above describes the light waveguide display device according to the embodiment of the present invention. According to the embodiment of the present invention, there is also provided a near-eye display device, which includes a lens and a frame for holding the lens close to the eye, and the lens includes the light waveguide display device according to the embodiment of the present invention. Preferably, the near-eye display device is an augmented reality display device or a virtual reality display device.

[0062] Those skilled in the art should understand that the scope of the invention involved in this application is not limited to the technical solutions formed by the specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the inventive concept. For example, the technical solutions formed by mutually replacing the above features with the technical features (but not limited to) disclosed in this application that have similar functions.

Claims

1. An anti-light leakage optical waveguide display device, comprising a first diffractive optical waveguide and a second diffractive optical waveguide stacked in parallel with each other, respectively used to couple in a first input light carrying image information and a second input light, and to expand the pupil and couple out the first input light to realize image display, wherein: The first diffractive optical waveguide comprises a first waveguide substrate and a first coupling-in grating and a first coupling-out grating arranged on the first waveguide substrate, the wavelength of the first input light is within a first wavelength range, and the maximum inclination angle of the first input light relative to the normal line of the surface of the first diffractive optical waveguide is θ0; and The first diffraction optical waveguide has a first surface facing the second diffraction optical waveguide, and an optical film layer is formed on the first surface, and the optical film layer is constructed as follows: within the first wavelength range, the average reflectivity for light with an incident angle less than a first threshold angle θ1 is R1, and the average reflectivity for light with an incident angle greater than a second threshold angle θ2 and less than a critical angle of total reflection is R2, θ2≥θ1≥θ0, 2%≤R1≤15%, and 40%≤R2≤90%.

2. The optical waveguide display device according to claim 1, wherein: 5%≤R1≤10%, and 60%≤R2≤80%.

3. The optical waveguide display device according to claim 1 or 2, wherein: θ2-θ1≤20o.

4. The optical waveguide display device according to claim 1 or 2, wherein: The first outcoupling grating diffracts the light propagating therein to generate diffraction light of ±2nd order, and the minimum angle formed by the diffraction light of ±2nd order with respect to the normal line is 5. The optical waveguide display device according to claim 1 or 2, wherein: The first outcoupling grating is configured to couple the light propagating therein from the first waveguide substrate through +1-order diffraction to realize image display, and the minimum angle formed by the -2-order diffracted light generated by the first outcoupling grating diffracting the light propagating therein with respect to the normal line is And the optical film layer is constructed to meet 6. The optical waveguide display device according to any one of claims 1 to 5, wherein: The first input light has an angle range [±H1, ±V1] relative to its center line, and the center line has a deflection angle [H2, V2] relative to the normal line, where H1 and H2 are angles in a first plane passing through the normal line, V1 and V2 are angles in a second plane passing through the normal line and perpendicular to the first plane, θ1>θ0', wherein:

7. The optical waveguide display device according to any one of claims 1 to 6, wherein: The wavelength of the second input light is within a second wavelength range, wherein the first wavelength range covers shorter wavelengths and the second wavelength range covers longer wavelengths.

8. The optical waveguide display device according to claim 7, wherein: The width of the first wavelength range is in the range of 100-150 nm, with a median wavelength in the range of 470-510 nm; and the width of the second wavelength range is in the range of 100-150 nm, with a median wavelength in the range of 570-610 nm.

9. The optical waveguide display device according to claim 7, wherein: The first input light is blue light and / or green light, and the second input light is red light.

10. The optical waveguide display device according to any one of claims 1 to 6, wherein: The wavelength of the second input light is within a second wavelength range, the first wavelength range at least partially overlaps with the second wavelength range, and light of the same wavelength in the first input light and the second input light has different viewing angle ranges.

11. The optical waveguide display device according to any one of claims 1 to 10, wherein: The first outcoupling grating is a reflective outcoupling grating, and is formed on a second surface of the first diffraction optical waveguide opposite to the first surface.

12. The optical waveguide display device according to claim 11, wherein: The second diffraction optical waveguide includes a second waveguide substrate and a second coupling-in grating and a second coupling-out grating arranged on the second waveguide substrate, the second coupling-out grating is aligned with the first coupling-out grating along the direction of the normal line, and the projection of the optical film layer along the normal line direction at least partially overlaps with the first coupling-out grating.

13. The light waveguide display device of claim 1, further comprising a third diffractive light waveguide stacked in parallel with the first diffractive light waveguide and the second diffractive light waveguide.

14. A near-eye display device, comprising a lens and a frame for holding the lens close to the eye, the lens comprising the optical waveguide display device according to any one of claims 1 to 13.

15. The near-eye display device according to claim 14, wherein: The near-eye display device is an augmented reality display device or a virtual reality display device.

Images