Array waveguide system and near-to-eye display equipment

Abstract

The invention relates to an array waveguide system and a near-to-eye display device, the system comprises a first waveguide sheet and a second waveguide sheet which are stacked, and the first waveguide sheet comprises a first turning pupil expanding area and a first coupling-out area which are sequentially arranged along a first direction; the first waveguide sheet comprises a first pupil expanding area and a first coupling-out area which are sequentially arranged in the first direction, the second waveguide sheet comprises a second pupil expanding area and a second coupling-out area which are sequentially arranged in the second direction, an included angle gamma is formed between the first direction and the second direction and is 70-110 degrees, and the first waveguide sheet and the second waveguide sheet are different in structure; the first coupling-out region and the second coupling-out region intersect and are correspondingly arranged; the cementing layer is arranged between the first waveguide sheet and the second waveguide sheet; and the entrance pupil structure is arranged close to the first coupling-in end and the second coupling-in end, so that the range of the eye box is effectively enlarged, the process processing is simpler, and the waveguide is more compact and miniaturized.

Description

Technical Field

[0001] The present invention relates to the field of augmented reality technology, and in particular to an array waveguide system and a near-eye display device. Background Art

[0002] Head-mounted displays for augmented reality use near-eye display technology, which allows people to watch the virtual images being projected while viewing their surroundings. The virtual images are superimposed on the real world perceived by the user, creating a more realistic experience and a stronger sense of immersion for the user.

[0003] In the process of implementing the embodiments of the present invention, the inventors found that most of the above related technologies are Birdbath, prism, free-form surface, optical waveguide, etc. The first three solutions all have the problem of increasing the field of view and reducing the volume; in order to solve this problem, the researchers proposed the optical waveguide solution.

[0004] According to the way of coupling in and out of light, optical waveguide solutions can be divided into two categories: array optical waveguide and diffraction optical waveguide. Compared with diffraction optical waveguide, array optical waveguide mainly transmits images by reflecting and refracting light based on the principle of geometric optics. Therefore, array optical waveguide will not introduce additional dispersion to the image and has a high light energy utilization rate.

[0005] The existing single-layer waveguide sheet has an effective area and an eye box size, where the effective area refers to the effective working area of ​​the waveguide without affecting the viewing effect. When people want to increase the eye box, they must increase the area of ​​the effective area. The increase in the effective area will make the waveguide area larger and the shape more difficult to control. In actual operation, increasing the effective area usually increases the number of dichroic films, which not only increases the height of the entire waveguide structure, but also increases the difficulty of waveguide processing. In addition, the larger the field of view angle, the larger the invalid area. Summary of the invention

[0006] In view of the problems existing in the prior art, the present invention provides an array waveguide system and a near-eye display device.

[0007] The technical solution of the present invention is as follows:

[0008] The present application provides an arrayed waveguide system, comprising:

[0009] A first waveguide plate and a second waveguide plate are stacked, wherein the first waveguide plate includes a first turning pupil expansion area and a first outcoupling area sequentially arranged along a first direction; the second waveguide plate includes a second pupil expansion area and a second outcoupling area sequentially arranged along a second direction, and the first direction and the second direction have an angle γ, and the angle γ=70°-110°, wherein,

[0010] The first turning pupil expansion area includes a first coupling end, a turning mirror and M first spectroscopic films arranged in sequence along the second direction, the first coupling end is arranged adjacent to the turning mirror, and the turning mirror and the first spectroscopic film are parallel to the third direction, the turning mirror is arranged at an inclination angle α1 with the second direction, and the first spectroscopic film is arranged at an inclination angle α2 with the second direction; the second pupil expansion area includes a second coupling end along the first direction, and N second spectroscopic films arranged in sequence at an inclination angle α3, the second spectroscopic film is arranged at an angle α4 with the third direction, and the angle α4 is 25°-75°; the first turning pupil expansion area intersects with the second pupil expansion area, and the first coupling end and the second coupling end are arranged correspondingly;

[0011] The first outcoupling region includes P third spectral films arranged in sequence at an inclination angle β1 along the first direction; the second outcoupling region includes Q fourth spectral films arranged in sequence at an inclination angle β2 along the second direction; the first outcoupling region intersects with the second outcoupling region and is arranged correspondingly; the first direction and the second direction are both perpendicular to the third direction;

[0012] A bonding layer, disposed between the first waveguide sheet and the second waveguide sheet;

[0013] The entrance pupil structure is arranged adjacent to the first coupling end and the second coupling end, and is used for coupling light into the first waveguide plate and the second waveguide plate.

[0014] As a preferred technical solution, the turning mirror is a total reflection mirror with an inclination angle of α1 = α2 ± 5°.

[0015] As a preferred technical solution, M first prismatic films are parallel along the second direction and arranged at a first spacing, with an inclination angle of α2 = 45° ± 5°, and M ≥ 2; N second prismatic films are parallel along the first direction and arranged at a second spacing, with an inclination angle of α3 = 45° ± 5°, and N ≥ 2, wherein M is the same or different from N, and the first spacing is the same or different from the second spacing.

[0016] As a preferred technical solution, the deflecting mirror is parallel to the first prismatic film and has a spacing with the adjacent first prismatic film, and the spacing is the same as or different from the first spacing.

[0017] As a preferred technical solution, P third prismatic films are parallel along the first direction and are arranged at a third spacing, with an inclination angle of β1 = 45° ± 5°, and P ≥ 2; Q fourth prismatic films are parallel along the second direction and are arranged at a fourth spacing, with an inclination angle of β2 = 45° ± 5°, and Q ≥ 2, wherein P and Q are the same or different, and the third spacing is the same or different from the fourth spacing.

[0018] As a preferred technical solution, the entrance pupil structure is projected into a triangle along the second direction, including a first long side, a second short side and a third hypotenuse. The first long side is arranged adjacent to the first coupling end and the second coupling end, and the third hypotenuse is arranged at an angle θ with the second short side.

[0019] As a preferred technical solution, a surface of the entrance pupil structure adjacent to the first coupling end and the second coupling end is parallel to the second coupling end, and the angle θ=60-80°.

[0020] As a preferred technical solution, the entrance pupil structure is a right-angled triangular prism with an angle θ=70°.

[0021] As a preferred technical solution, the bonding layer is an optical bonding layer, which satisfies the relationship:

[0022] Alternatively, the bonding layer includes a first magnesium fluoride coating, an optical bonding layer and a second magnesium fluoride coating, and the optical bonding layer is located between the first magnesium fluoride coating and the second magnesium fluoride coating, satisfying the relationship:

[0023] The refractive index of the first waveguide and the second waveguide are both n w , the refractive index of the optical adhesive layer n G The refractive index of the first magnesium fluoride coating and the second magnesium fluoride coating are both n c The transmission angle ranges in the first waveguide plate and the second waveguide plate are both ω, the third beam splitter film has an inclination angle β1 along the first direction, and the fourth beam splitter film has an inclination angle β2 along the second direction, wherein β=β1=β2.

[0024] The present application also provides a near-eye display device, comprising the above-mentioned array waveguide system.

[0025] The technical solution adopted by the present invention achieves the following beneficial effects:

[0026] The present application proposes an arrayed waveguide system, which is achieved by superimposing another layer of two-dimensional array waveguide sheet on the basis of a traditional single-layer two-dimensional array waveguide sheet by gluing, that is, a double-layer array waveguide structure. The two array waveguide structures are different, and light enters the two waveguide sheets respectively through the entrance pupil structure for transmission until it is coupled out to the human eye. The eye box area of ​​the double-layer array waveguide is seamlessly spliced ​​or partially overlapped, which effectively increases the eye box range, has a high light transmission rate, is simpler in process processing, and makes the waveguide more compact and miniaturized. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments, which constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions explain the present invention and do not constitute improper limitations on the present invention. In the drawings:

[0028] Figure 1 This is a schematic diagram of the structure of the first waveguide disclosed in this embodiment;

[0029] Figure 2 A side view of the first waveguide plate structure disclosed in this embodiment;

[0030] Figure 3 This is a schematic diagram of the structure of the first waveguide disclosed in this embodiment;

[0031] Figure 4 This is a schematic diagram of the structure of the second waveguide disclosed in this embodiment;

[0032] Figure 5 This is a schematic diagram of the structure of the second waveguide disclosed in this embodiment;

[0033] Figure 6 This is a schematic diagram of the structure of the second waveguide disclosed in this embodiment;

[0034] Figure 7 Schematic diagram of the structure of the array waveguide system disclosed in this embodiment.

[0035] Description of reference numerals:

[0036] A first waveguide plate 100; a second waveguide plate 200; a first coupling end 101; a turning mirror 102; a first spectroscopic film 103; a third spectroscopic film 104; a second coupling end 201; a second spectroscopic film 202; a fourth spectroscopic film 203; an entrance pupil structure 300; and an array waveguide system 400. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the specific embodiments of the present invention and the corresponding drawings. In the description of the present invention, it should be noted that the term "or" is usually used in the sense of including "and / or", unless the content clearly indicates otherwise.

[0038] In the description of the present invention, it should be understood that "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through a medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0039] In addition, those skilled in the art should understand that, in the disclosure of the present invention, the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, the above terms should not be understood as limiting the present invention.

[0040] Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] Example

[0042] according to Figure 1-Figure 7 , an embodiment of the present invention provides an array waveguide system 400, comprising:

[0043] The first waveguide plate and the second waveguide plate 200 are stacked, the first waveguide plate includes a first turning pupil expansion area and a first coupling-out area sequentially arranged along a first direction; the second waveguide plate 200 includes a second pupil expansion area and a second coupling-out area sequentially arranged along a second direction, the first direction and the second direction have an angle γ, and the angle γ=70°-110°, wherein,

[0044] The first turning pupil expansion area includes a first coupling end 101, a turning mirror 102 and M first dichroic films 103 arranged in sequence along the second direction, the first coupling end 101 is arranged adjacent to the turning mirror 102, and the turning mirror 102 and the first dichroic film 103 are parallel to the third direction, the turning mirror 102 is arranged at an inclination angle α1 with the second direction, and the first dichroic film 103 is arranged at an inclination angle α2 with the second direction; the second pupil expansion area includes a second coupling end 201 along the first direction, and N second dichroic films 202 arranged in sequence at an inclination angle α3, the second dichroic film 202 is arranged at an angle α4 with the third direction, and the angle α4 is 25°-75°; the first turning pupil expansion area intersects with the second pupil expansion area, and the first coupling end 101 and the second coupling end 201 are arranged correspondingly;

[0045] The first outcoupling region includes P third prismatic films 104 arranged in sequence at an inclination angle β1 along the first direction; the second outcoupling region includes Q fourth prismatic films 203 arranged in sequence at an inclination angle β2 along the second direction; the first outcoupling region intersects with the second outcoupling region and is arranged correspondingly; the first direction and the second direction are both perpendicular to the third direction;

[0046] A bonding layer, provided between the first waveguide sheet 100 and the second waveguide sheet 200;

[0047] The entrance pupil structure 300 is disposed adjacent to the first coupling end 101 and the second coupling end 201 , and is used to couple light into the first waveguide plate 100 and the second waveguide plate 200 .

[0048] Based on the existing method of increasing the eye box, there are problems such as large waveguide area, high process difficulty, and difficult to control the shape. This embodiment proposes an arrayed waveguide system 400, which is based on the traditional single-layer two-dimensional array waveguide sheet. A layer of two-dimensional array waveguide sheet is superimposed by gluing, that is, a double-layer array waveguide structure. The two layers of array waveguide structures are different. The incident light enters the two waveguide sheets respectively through the entrance pupil structure 300 for transmission until it is coupled out to the human eye. The eye box area of ​​the double-layer array waveguide is seamlessly spliced ​​or partially overlapped, which effectively increases the eye box range. The light transmission rate is high, and the process processing will be simpler, and the waveguide is made more compact and miniaturized.

[0049] Preferably, the turning mirror 102 is a total reflection mirror with an inclination angle of α1 = α2 ± 5°.

[0050] Preferably, M first prismatic films 103 are parallel along the second direction and are arranged at a first spacing, with an inclination angle of α2 = 45°±5°, and M≥2; N second prismatic films 202 are parallel along the first direction and are arranged at a second spacing, with an inclination angle of α3 = 45°±5°, and N≥2, wherein M is the same as or different from N, and the first spacing is the same as or different from the second spacing.

[0051] Preferably, the deflection mirror 102 is a total reflection mirror, which is parallel to the first prismatic film 103 and has a spacing with the adjacent first prismatic film 103 , and the spacing is the same as or different from the first spacing.

[0052] In this embodiment, the light coupled into the first waveguide plate 100 through the entrance pupil structure 300 for total reflection transmission is set as the first image light, and the light entering the second waveguide plate 200 for total reflection transmission is set as the second image light.

[0053] The first waveguide plate 100 and the second waveguide plate 200 generally include an upper substrate and a lower substrate, which can be made of transparent materials such as transparent glass or transparent resin. Glass and resin have good optical properties and are helpful to improve the imaging quality of the array optical waveguide assembly. In this embodiment, the first waveguide plate 100 and the second waveguide plate 200 are preferably made of glass materials, which are low in cost and easy to process. Figure 1-Figure 3 ,in, Figure 2 is a side view of the first waveguide plate 100, Figure 3 for Figure 2The enlarged cross-sectional view in the middle dotted rectangular frame shows that the first waveguide 100 includes a first turning pupil expansion area and a first coupling-out area arranged in sequence along the first direction, the first turning pupil expansion area includes a first coupling-in end 101, a turning mirror 102 and M first bezel films 103, the turning mirror 102 and the M first bezel films 103 are arranged in sequence along the second direction, and the first coupling-in end 101 is arranged adjacent to the turning mirror 102, wherein M≥2, and the M first bezel films 103 can be understood as a first bezel film 103 array.

[0054] Further, see Figure 1 The turning mirror 102 is a total reflection mirror embedded between the upper substrate and the lower substrate and perpendicular to the upper substrate and the lower substrate. The total reflection mirror is set at an inclination angle α1 along the second direction, that is, the total reflection mirror is parallel to the third direction and has an angle α1 with the second direction. According to Figure 1-Figure 3 , used to turn the first image light incident into the first waveguide 100 through the first coupling end 101, and transfer it to the first beam splitter film 103 array in the second direction; the M first beam splitter films 103 refer to a plurality of beam splitter films parallel to each other and having beam splitting characteristics, each beam splitter film is embedded between the upper substrate and the lower substrate of the first waveguide 100, and is connected to the upper substrate and the lower substrate respectively, each beam splitter film is perpendicular to the upper substrate and the lower substrate, and has an inclination angle α2 along the second direction, and by adjusting the reflectivity and transmittance of the beam splitter film, each beam splitter film can be used to reflect and transmit the light that is totally reflected and propagated inside the first waveguide 100 and refraction, the transmittance and reflectivity of the dichroic film can be set according to actual needs and are not limited here. In short, the first dichroic film 103 is parallel to the third direction and has an angle α2 with the second direction, wherein the inclination angle α2=40°-50°, the inclination angle α1=α2±5°, for example, the inclination angle α2 can be 40°, 42°, 45°, 48°50°, so as to deflect the first image light through the total reflection mirror, so as to realize the transmission of the first image light along the second direction to the first dichroic film 103 array, and the first dichroic film 103 array then dilates the first image light along the second direction and outputs it to the first outcoupling area along the first direction.

[0055] Preferably, P third prismatic films 104 are parallel along the first direction and arranged at a third pitch, with an inclination angle β1=45°; Q fourth prismatic films 203 are parallel along the second direction and arranged at a fourth pitch, with an inclination angle β2=45°, wherein P≥Q, and the third pitch is the same as or different from the fourth pitch.

[0056] Similarly, according to Figure 4-Figure 6 The second waveguide plate 200 includes a second pupil expansion area and a second coupling-out area sequentially arranged along the second direction. The second pupil expansion area includes a second coupling-in end 201 sequentially arranged along the first direction, and N second splitter films 202, N≥2, that is, a second splitter film 202 array.

[0057] Further, the second waveguide plate 200 is Figure 4-Figure 6 , Figure 5 for Figure 4 The enlarged cross-sectional view indicated by the arrow in the second pupil dilation structure. Figure 6 FIG. 2 is an enlarged cross-sectional view of the second outcoupling structure in the second waveguide 200. The N second splitter films 202 refer to a plurality of splitter films that are parallel to each other and have splitter characteristics. Each splitter film is embedded between the upper substrate and the lower substrate of the second waveguide 200 and is connected to the upper substrate and the lower substrate respectively. Each splitter film is arranged at an inclination angle α3 along the first direction and is arranged at an angle α4 with the third direction. Figure 5 Similarly, by adjusting the reflectivity and transmittance of each splitter film, each splitter film can be used to reflect, transmit and refract the light that is totally reflected and propagated inside the second waveguide 200. The transmittance and reflectivity of the splitter film can be set according to actual needs and are not limited here. Among them, the inclination angle α3=40°-50°, the α4 angle is 25°-75°, and the α4 angle can be 25°, 30°, 45°, 48°, 56°, 60°, etc., so that the second image light that enters the second waveguide 200 through the second coupling-in end 201 is transmitted to the second splitter film 202 array for pupil expansion and turning in the first direction, and then is transmitted to the second coupling-out area along the second direction. Preferably, the inclination angle α2=α3=45°, the output light of each of the first waveguide 100 and the second waveguide 200 is more uniform, and the displayed image is clearer.

[0058] Furthermore, after a bonding layer is provided between the first waveguide sheet 100 and the second waveguide sheet 200, an array waveguide system 400 is formed. Figure 7, from the overall point of view, the first turning pupil expansion area intersects with the second pupil expansion area, and the first coupling end 101 and the second coupling end 201 are correspondingly arranged, and the first direction and the second direction have an angle γ=70°-110°. For ease of understanding, a coordinate system XYZ is established. According to the arrangement direction of the first turning pupil expansion area and the first coupling area, the first waveguide plate 100 is set to be parallel to the first direction and parallel to the X-axis. According to the arrangement direction of the second pupil expansion area and the second coupling area, the second waveguide plate 200 is set to be parallel to the second direction and parallel to the Y-axis. The first coupling end 101 and the second coupling end 201 are located at the origin of the coordinate system. That is to say, the current state is that the first direction is perpendicular to the second direction, that is, γ=90°. The second coupling end 201 is used as the rotation point, clockwise or counterclockwise. The second waveguide 200 is rotated 20°, wherein the main difference between the second waveguide 200 and the first waveguide 100 is that the second beam splitter film 202 has an angle α4 with the third direction, and the first beam splitter film 103 in the first waveguide 100 is strictly parallel to the third direction. It can also be understood that the first beam splitter film 103 is perpendicular to the XY plane, and the second beam splitter film 202 has an angle α4 with respect to the XY plane. Due to the existence of the angle α4, the total reflection angle of the second image light transmitted in the second waveguide 200 is modulated. Figure 7 , taking γ=90°, M=N, P=Q as an example, the first turning pupil expansion area is perpendicular to the second pupil expansion area, and the first coupling end 101 intersects with the second coupling end 201 and is completely correspondingly arranged, the first coupling area is perpendicular to the second coupling out area, forming a grid-like shape. For ease of understanding, it is briefly described as the first waveguide plate 100 and the second waveguide plate 200 are perpendicular and superimposed. If it is arranged at the same angle as the first wave plate 100, that is, α4=90°, it is equivalent to the first waveguide plate 100 and the second waveguide plate 200 having completely the same structure. In the same manner, the two are arranged to be vertically stacked on each other. Under this arrangement, the image coupled out by the first waveguide 100 and the second waveguide 200 is in a 90° relationship, which is obviously not a single image, but is equivalent to images in two directions. Therefore, by setting the angle α4 = 25°-75°, the image coupled in and out of the second waveguide 200 can be rotated 90°, so that the first waveguide 100 and the second waveguide 200 can couple out the same image in the same direction, thereby effectively expanding the eye box and helping to enhance the user's viewing experience and reduce visual fatigue.

[0059] Further, by reasonably setting the angle of α4 for different double-layer array waveguide structures, image output in the same direction can be achieved, for example, γ=70°-110°, and the parameters M, N, P, Q, the first spacing, the second spacing, the inclination angle α1, the inclination angle α2, and the inclination angle α3 in the structures of the first waveguide plate 100 and the second waveguide plate 200 may be the same, or may not be completely the same, for example, M is different from N, P is different from Q, and / or the first spacing is the same or different from the second spacing, and / or the inclination angle α1 is the same or different from the inclination angle α2, and / or the inclination angle α2 is the same or different from the inclination angle α3; or M is the same as N, P is different from Q, and / or The first spacing is the same or different from the second spacing, and / or the inclination angle α1 is the same as the inclination angle α2, and the interval is the same or different from the first spacing, and / or the inclination angle α2 is the same as or different from the inclination angle α3; or M is the same as N, P is different from Q, and / or the first spacing is the same or different from the second spacing, and / or the inclination angle α1 is different from the inclination angle α2, and / or the inclination angle α2 is the same as or different from the inclination angle α3, etc., and the specific optimal angle of α4 can be selected according to the actual situation. Not only can the image consistency output by the first waveguide 100 and the second waveguide 200 be well achieved, but also the eye box range can be expanded, thereby greatly improving the user experience.

[0060] Further, as shown in FIG7, the first waveguide sheet 100 and the second waveguide sheet 200 described above are superimposed to form an arrayed waveguide system 400, and their respective effective areas and eye boxes will overlap partially and not overlap partially. By setting the values ​​of one or more of the parameters M, N, P, Q, α1, α2, α3, α4, the first spacing, and the second spacing of the arrayed waveguide, the position and size of the eye box can be effectively adjusted, so that the eye box can be spliced ​​as follows: Figure 7 As shown, compared with the existing single-layer array waveguide method of adding a splitter film, under the condition of the same effective area as the existing method, the present embodiment can effectively increase the eye box range, reduce unnecessary ineffective areas, make the structure more compact and miniaturized, and output the best image. According to the above-mentioned method, the respective eye box areas formed by the array waveguide system 400 can be seamlessly spliced ​​or overlapped up and down and left and right to form a large eye box, which can effectively increase the eye box range, improve the light transmission efficiency, realize two-dimensional pupil expansion, and simplify the difficulty of array waveguide processing.

[0061] Preferably, the entrance pupil structure 300 is projected into a triangle along the second direction, including a first long side, a second short side and a third hypotenuse, the first long side is arranged adjacent to the first coupling end 101 and the second coupling end 201, and the third hypotenuse is arranged at an angle θ with the second short side.

[0062] Preferably, the entrance pupil structure 300 is adjacent to one side of the first coupling end 101 and the second coupling end 201 , and is parallel to the second coupling end 201 , with an angle θ=60-80°.

[0063] Preferably, the entrance pupil structure 300 is a right-angled triangular prism, and the angle θ=70°.

[0064] For details, see Figure 2 The array waveguide system 400 also includes an entrance pupil structure 300. The entrance pupil structure 300 is usually a geometric prism, which is arranged adjacent to the first coupling end 101 and the second coupling end 201, and is mainly used to couple the light emitted by the light engine into the array waveguide system 400 for total reflection transmission. In this embodiment, the entrance pupil structure 300 is a triangular prism, which is projected into a triangle along the second direction, including a first long side, a second short side and a third hypotenuse. The first long side is arranged adjacent to the first coupling end 101 and the second coupling end 201, and the third hypotenuse and the second short side form an angle θ=60-80°. A side of the triangular prism adjacent to the first coupling end 101 and the second coupling end 201 is parallel to the second coupling end 201, ensuring that within γ=70°-110°, the image light incident on the entrance pupil structure 300 can all enter the first image light into the first waveguide plate 100, and the second image light into the second waveguide. Preferably, the entrance pupil structure 300 is a right-angled triangular prism with an angle of θ=70°, which helps to efficiently and quickly couple the light emitted by the light engine into the array waveguide system 400 through the right-angled triangular prism within the range of γ=70°-110°, and at the same time evenly divide the light into a first image light and a second image light. The first image light is incident on the first waveguide plate 100, and the second image light is coupled into the second waveguide plate 200, thereby realizing a double-layer waveguide.

[0065] Preferably, the adhesive layer is an optical adhesive layer, satisfying the relationship:

[0066] Alternatively, the bonding layer includes a first magnesium fluoride coating, an optical bonding layer and a second magnesium fluoride coating, and the optical bonding layer is located between the first magnesium fluoride coating and the second magnesium fluoride coating, satisfying the relationship:

[0067] The refractive index of the first waveguide plate 100 and the second waveguide plate 200 are both n w , the refractive index of the optical adhesive layer n G The refractive index of the first magnesium fluoride coating and the second magnesium fluoride coating are both n c The transmission angle ranges in the first waveguide plate 100 and the second waveguide plate 200 are both ω, the third beam splitter film 104 has an inclination angle β1 along the first direction, and the fourth beam splitter film 203 has an inclination angle β2 along the second direction, wherein β=β1=β2.

[0068] Specifically, the arrayed waveguide system 400 has two structures. The first structure is that the first waveguide plate 100 and the second waveguide plate 200 are stacked, and an optical adhesive layer is provided between the two, satisfying the following relationship:

[0069]

[0070] The second type is based on the first type, in which a first magnesium fluoride coating is provided between the first waveguide plate 100 and the optical adhesive layer, and a second magnesium fluoride coating is provided between the second waveguide plate 200 and the optical adhesive layer, satisfying the following relationship:

[0071]

[0072] The refractive index of the first waveguide plate 100 and the second waveguide plate 200 are both n w , the refractive index of the optical adhesive layer n G The refractive index of the first magnesium fluoride coating and the second magnesium fluoride coating are both n C The transmission angle ranges in the first waveguide plate 100 and the second waveguide plate 200 are both ω, the third beam splitter film 104 has an inclination angle β1 along the first direction, and the fourth beam splitter film 203 has an inclination angle β2 along the second direction, wherein β=β1=β2.

[0073] Preferably, the thickness of the optical adhesive layer is 0.5-5 μm, the thickness of the first magnesium fluoride coating and the second magnesium fluoride coating is 80-500 nm, the thickness of the first magnesium fluoride coating and the second magnesium fluoride coating are the same or different, the thickness of the optical adhesive layer in the first structure is the same or different from the thickness of the optical adhesive layer in the second structure, and the specific thickness is selected by those skilled in the art according to actual needs and is not specifically limited here.

[0074] An adhesive layer is provided between the first waveguide plate 100 and the second waveguide plate 200, and the adhesive layer is used to fix the first waveguide plate 100 and the second waveguide plate 200 to form an array waveguide system 400. It also helps to avoid light leakage during light transmission, thereby achieving lossless propagation and preventing light transmitted between the two layers of waveguide plates from interfering with each other, thereby effectively improving image quality.

[0075] This embodiment also provides a near-eye display device, including the above-mentioned array waveguide system 400, which effectively expands the eye box range and improves the user experience.

[0076] The above is a detailed introduction to an arrayed waveguide system and a near-eye display device according to an embodiment of the present application. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea. At the same time, for a person skilled in the art, according to the idea of ​​the present application, there may be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. An array waveguide system, characterized in that: include: A first waveguide plate and a second waveguide plate are stacked, wherein the first waveguide plate includes a first turning pupil expansion area and a first outcoupling area sequentially arranged along a first direction; the second waveguide plate includes a second pupil expansion area and a second outcoupling area sequentially arranged along a second direction, and the first direction and the second direction have an angle γ, and the angle γ=70°-110°, wherein, The first turning pupil expansion area includes a first coupling end, a turning mirror and M first dichroic films arranged in sequence along the second direction, the first coupling end is arranged adjacent to the turning mirror, and the turning mirror and the first dichroic film are parallel to the third direction, the turning mirror is arranged at an inclination angle α1 with the second direction, and the first dichroic film is arranged at an inclination angle α2 with the second direction; the second pupil expansion area includes a second coupling end along the first direction, and N second dichroic films arranged in sequence at an inclination angle α3, the second dichroic film is arranged at an angle α4 with the third direction, and the angle α4 is 25°-75°; the first turning pupil expansion area intersects with the second pupil expansion area, and the first coupling end and the second coupling end are arranged correspondingly; The first outcoupling region includes P third spectral films arranged in sequence at an inclination angle β1 along a first direction; the second outcoupling region includes Q fourth spectral films arranged in sequence at an inclination angle β2 along the second direction; the first outcoupling region intersects with the second outcoupling region and is arranged correspondingly; the first direction and the second direction are both perpendicular to the third direction; A bonding layer, provided between the first waveguide sheet and the second waveguide sheet; The entrance pupil structure is arranged adjacent to the first coupling end and the second coupling end, and is used for coupling light into the first waveguide plate and the second waveguide plate.

2. The arrayed waveguide system according to claim 1, characterized in that: The turning mirror is a total reflection mirror, and the inclination angle α1=α2±5°.

3. The arrayed waveguide system according to claim 2, characterized in that: The M first prismatic films are parallel along the second direction and arranged at a first spacing, the inclination angle α2 = 45°±5°, and M≥2; the N second prismatic films are parallel along the first direction and arranged at a second spacing, the inclination angle α3 = 45°±5°, and N≥2, wherein M is the same as or different from N, and the first spacing is the same as or different from the second spacing.

4. The arrayed waveguide system according to claim 3, characterized in that: The deflecting mirror is parallel to the first prismatic film and has a spacing with the adjacent first prismatic film, and the spacing is the same as or different from the first spacing.

5. The arrayed waveguide system according to claim 4, characterized in that: The P third prismatic films are parallel along the first direction and are arranged at a third spacing, the inclination angle β1 = 45°±5°, P≥2; the Q fourth prismatic films are parallel along the second direction and are arranged at a fourth spacing, the inclination angle β2 = 45°±5°, Q≥2, wherein P is the same as or different from Q, and the third spacing is the same as or different from the fourth spacing.

6. The arrayed waveguide system according to claim 5, characterized in that: The entrance pupil structure is projected into a triangle along the second direction, including a first long side, a second short side and a third hypotenuse. The first long side is arranged adjacent to the first coupling end and the second coupling end, and the third hypotenuse is arranged at an angle θ with the second short side.

7. The arrayed waveguide system according to claim 6, characterized in that: A surface of the entrance pupil structure adjacent to the first coupling end and the second coupling end is parallel to the second coupling end, and the included angle θ=60-80°.

8. The arrayed waveguide system according to claim 7, characterized in that: The entrance pupil structure is a right-angled triangular prism, and the included angle θ=70°.

9. The arrayed waveguide system according to any one of claims 1 to 8, characterized in that: The bonding layer is an optical bonding layer, which satisfies the relationship: Alternatively, the bonding layer includes a first magnesium fluoride coating, an optical adhesive layer and a second magnesium fluoride coating, and the optical adhesive layer is located between the first magnesium fluoride coating and the second magnesium fluoride coating, satisfying the relationship: The refractive index of the first waveguide plate and the second waveguide plate are both n w , the refractive index n of the optical adhesive layer G The refractive index of the first magnesium fluoride coating and the second magnesium fluoride coating are both n c , the transmission angle ranges in the first waveguide plate and the second waveguide plate are both ω, the third beam splitter film has an inclination angle β1 along the first direction, and the fourth beam splitter film has an inclination angle β2 along the second direction, wherein β=β1=β2.

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

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