Waveguide structure, near-to-eye display device and use method of near-to-eye display device

Abstract

The invention provides a waveguide structure, a near-to-eye display device and a use method of the near-to-eye display device. The waveguide structure comprises a first waveguide and a second waveguide which are stacked, a coupling structure is arranged on the first waveguide; a plurality of first partial transmission and partial reflection mirrors are obliquely arranged in the first waveguide; the interior of the second waveguide is divided into areas corresponding to the first transmission partial reflectors; a plurality of mirrors are arranged in each region, and the included angles between the mirrors in the plurality of regions and the total internal reflection surface are gradually increased; and the control switch is corresponding to each area, and when any control switch is turned on, the light can be transmitted from the first waveguide to the corresponding area in the second waveguide. According to the technical scheme, the two waveguide layers are stacked, the control switch is used for controlling the light to enter the different areas of the second waveguide layer, and the mirrors with different inclination angles are arranged in the different areas, so that the different areas of the image can be coupled out of the second waveguide layer through the mirrors in the different areas in the second waveguide layer, and the field angle is increased.

Description

Technical Field

[0001] This application relates to the field of near-eye display technology, and in particular, to a waveguide structure, a near-eye display device, and a method of using the same. Background Art

[0002] An optical waveguide is a device that uses the principle of total internal reflection of light to couple light into the interior of the waveguide from one surface, and finally realizes the propagation of light through the total internal reflection of light inside the waveguide. The field of view angle, that is, the maximum angular range that the human eye can observe in the device, directly determines the visual field width of the user in the virtual environment. Existing technical solutions for increasing the field of view angle include reducing the critical total internal reflection angle of light transmission in the waveguide by using glass with a high refractive index, thereby increasing the angular range of light beam transmission in the waveguide; another existing solution is to increase the final field of view angle entering the human eye by expanding the field of view angle of the projected image and transmitting it through the waveguide.

[0003] By increasing the refractive index of the glass, although the angular range of light allowed to pass through the waveguide can be increased, the highest refractive index of common glass is about 2.0, and the improvement range is still limited. Moreover, high-refractive-index glass usually has a low Abbe number, which means that the glass has a stronger dispersion ability, which will affect the display effect of color images; furthermore, this method still needs to cooperate with expanding the field of view angle of the coupled-in image, which will increase the size of the optical engine and affect the miniaturization and lightweight of AR glasses. Summary of the Invention

[0004] This application provides a waveguide structure, a near-eye display device, and a method of using the same to improve the display effect of the near-eye display device.

[0005] In a first aspect, a waveguide structure is provided. The waveguide structure includes a first waveguide and a second waveguide stacked on top of each other; wherein, a coupling structure is provided on the first waveguide;

[0006] A plurality of first partially transmissive and partially reflective mirrors are disposed obliquely in the first waveguide and arranged at intervals;

[0007] Along the length direction of the second waveguide, the second waveguide is divided into regions corresponding to each first partially transmissive and partially reflective mirror; a plurality of mirrors are disposed in parallel in each region, wherein the mirror farthest from the coupling structure is a reflective mirror, and the remaining mirrors are second partially transmissive and partially reflective mirrors; along the direction away from the coupling structure, the angle between the mirrors in the plurality of regions and the total internal reflection surface of the second waveguide gradually increases;

[0008] A control switch corresponding to each region is provided between the first waveguide and the second waveguide. When any control switch is turned on, light can propagate from the first waveguide to the corresponding region in the second waveguide and be coupled out through the plurality of mirrors in this region.

[0009] In the above technical solution, by stacking two waveguide layers and controlling the switch to control the light to enter different regions of the second waveguide layer, and setting mirrors with different tilt angles in different regions, different regions of the image can be coupled out of the second waveguide layer through the mirrors in different regions of the second waveguide layer, thereby increasing the field of view angle.

[0010] In a specific implementable embodiment, the control switch includes a liquid crystal layer and a polarizing film; wherein,

[0011] When power is applied to the liquid crystal layer, the control switch can transmit light of the first polarization state;

[0012] When power is not applied to the liquid crystal layer, the control switch can transmit light of the second polarization state.

[0013] In a specific implementable embodiment, along the length direction of the second waveguide, the control switch corresponding to each region is located between the first mirror in this region and the last mirror in the adjacent region.

[0014] In a specific implementable embodiment, the control switch corresponds one-to-one with the first partial transmission and partial reflection mirror.

[0015] In a specific implementable embodiment, along the length direction of the second waveguide, the lengths of any two of the regions may be equal.

[0016] In a specific implementable embodiment, the first waveguide and the second waveguide are adhesively connected through an adhesive layer; wherein,

[0017] The refractive index of the first waveguide is greater than that of the adhesive layer, and the refractive index of the second waveguide is greater than that of the adhesive layer.

[0018] In a second aspect, a near-eye display device is provided, and the near-eye display device includes an optical engine and the waveguide structure according to any one of the above; wherein,

[0019] The light emitted by the optical engine is coupled into the first waveguide through the coupling-in structure.

[0020] In the above technical solution, by stacking two waveguide layers and controlling the switch to control the light to enter different regions of the second waveguide layer, and setting mirrors with different tilt angles in different regions, different regions of the image can be coupled out of the second waveguide layer through the mirrors in different regions of the second waveguide layer, thereby increasing the field of view angle.

[0021] In a specific implementable embodiment, the near-eye display device further includes a control chip, and the control chip is configured to control the opening and closing of the control switch according to the correspondence between the polarization state of the light and the region.

[0022] In a third aspect, a method for using a near-eye display device is provided, where the near-eye display device is the near-eye display device described in any one of the above; the method includes the following steps:

[0023] Emit light rays for displaying an image through an optical engine;

[0024] Propagate the light rays into the first waveguide through a coupling structure, and reflect the light rays to the control switch through the first partial transmission and partial reflection mirror;

[0025] Control, through the control switch, the light rays to propagate to corresponding regions in the second waveguide.

[0026] In the above technical solution, by stacking two waveguide layers and controlling, through a control switch, the light rays to enter different regions of the second waveguide layer, and by setting mirrors with different tilt angles in different regions, different regions of the image can thus be coupled out of the second waveguide layer through the mirrors in different regions of the second waveguide layer, increasing the field of view angle.

[0027] In a specific feasible implementation, the step of emitting light rays for displaying an image through an optical engine is specifically:

[0028] Sequentially emit light rays corresponding to images of different regions through the optical engine. Description of the Drawings

[0029] Figure 1 A schematic diagram of an application scenario of a waveguide structure in the prior art;

[0030] Figure 2 A schematic diagram of the waveguide structure provided by an embodiment of the present application;

[0031] Figure 3 A schematic diagram of the structure of the second waveguide provided by an embodiment of the present application;

[0032] Figure 4 A schematic diagram of the reflected light rays of mirrors with different tilt angles provided by an embodiment of the present application. Detailed Embodiments

[0033] In order to make the objectives, technical solutions, and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings.

[0034] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in one or more embodiments of this specification should have the ordinary meanings understood by those of ordinary skill in the art to which this disclosure belongs. The terms "first", "second" and similar terms used in one or more embodiments of this specification do not indicate any order, quantity or importance, but are only used to distinguish different components. Words such as "including" or "comprising" mean that the elements or objects appearing before this word cover the elements or objects listed after this word and their equivalents, without excluding other elements or objects. Words such as "connected" or "coupled" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right", etc. are only used to represent relative positional relationships. When the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0035] To facilitate the understanding of the waveguide structure provided by the embodiments of the present application, its application scenario will be described first. The waveguide structure provided by the embodiments of the present application is applied to a near-eye display device, and the waveguide structure provided by the embodiments of the present application is applied to AR (Augmented Reality) or VR (Virtual Reality) devices. In the current optical waveguide, when light propagates, the field of view angle is relatively small, which affects the display effect of AR or VR devices. For this reason, the embodiments of the present application provide a waveguide structure to improve the light propagation effect of the waveguide structure, and thus improve the display effect of AR or VR devices. The following will describe it in detail with specific drawings and embodiments.

[0036] Refer to Figure 1 as shown, Figure 1 which shows an application schematic diagram of the waveguide structure 3 in the prior art. When the waveguide structure 3 is in use, the light emitted by the light engine 1 is coupled into the waveguide structure 3 through the coupling structure 2 in the waveguide structure 3. The waveguide structure 3 has two total internal reflection surfaces arranged oppositely, and the light can propagate in the waveguide structure 3 through total reflection on the two total internal reflection surfaces. An output structure 4 is also arranged in the waveguide structure 3. As Figure 1 shown in, the output structure 4 is a plurality of partially transmissive and partially reflective mirrors arranged at intervals. When the light propagates to the output structure 4, for any one of the partially transmissive and partially reflective mirrors, part of the light is reflected by the partially transmissive and partially reflective surface and then coupled out of the waveguide structure 3 and can be irradiated into the human eye. And the other part of the light continues to propagate after being transmitted by the partially transmissive and partially reflective mirror.

[0037] It can be seen from Figure 1 that since the tilt angles of the partially transmissive and partially reflective surfaces are the same, and the angles of light with different field of view angles when coupled into the waveguide structure 3 are different, it affects the maximum field of view angle when the user views.

[0038] To this end, an embodiment of the present application provides a waveguide structure for improving the maximum viewing angle when a user views.

[0039] Refer to Figure 2 as shown Figure 2 As shown, a schematic structural diagram of the waveguide structure provided by the embodiment of the present application is shown. The waveguide structure provided by the embodiment of the present application includes two stacked waveguides. For convenience of description, the two waveguides are respectively named the first waveguide 10 and the second waveguide 20. The first waveguide 10 and the second waveguide 20 are stacked, and the stacking direction is along the direction perpendicular to the length directions of the first waveguide 10 and the second waveguide 20.

[0040] When specifically arranged, a coupling structure 30 is provided on the first waveguide 10, and the light emitted by the optical engine 100 can be coupled into the first waveguide 10 through the coupling structure 30 and propagate in the first waveguide 10. Among them, the coupling mechanism 30 can be a coupling grating.

[0041] In addition, a plurality of partially transmissive and partially reflective mirrors 21 are also provided in the first waveguide 10. For convenience of description, the partially transmissive and partially reflective mirror 21 is named the first partially transmissive and partially reflective mirror. The plurality of first partially transmissive and partially reflective mirrors are inclined and arranged at intervals along the length direction of the first waveguide 10. When specifically arranged, the inclination angles of the plurality of first partially transmissive and partially reflective mirrors are the same. When the light emitted by the optical engine 100 is coupled into the first waveguide 10 through the coupling structure 30, it is totally reflected and propagated between the two total internal reflection surfaces of the first waveguide 10, and the light is partially reflected and partially transmitted through the plurality of first partially transmissive and partially reflective mirrors. Among them, the partially reflected light can be coupled out of the first waveguide 10, and the partially transmitted light can continue to propagate in the first waveguide 10.

[0042] Refer to together Figure 2 and Figure 3 as shown Figure 3 As shown, a schematic structural diagram of the second waveguide 20 in the embodiment of the present application is shown. The inside of the second waveguide 20 is divided into a plurality of regions 201, and the plurality of regions 201 are arranged along the length direction of the second waveguide 20. Among them, the plurality of regions 201 correspond to the plurality of first partially transmissive and partially reflective mirrors, and they are in one-to-one correspondence. In addition, a control switch 40 is provided between the first waveguide 10 and the second waveguide 20. The control switch 40 corresponds to each region 201 one-to-one and is used to control whether the light reflected by the first partially transmissive and partially reflective mirror can enter the corresponding region 201. When any one of the control switches 40 is turned on, the light can propagate from the first waveguide 10 to the corresponding area in the second waveguide 20 and be coupled out through the plurality of mirrors 21 in the region 201.

[0043] Exemplarily, when the control switch 40 is turned on, the light reflected by the first partially transmissive and partially reflective mirror can pass through the control switch 40 and enter the second waveguide 20, and propagate in the corresponding area 201 of the first partially transmissive and partially reflective mirror. When the control switch 40 is turned off, the light reflected by the first partially transmissive and partially reflective mirror cannot enter the corresponding area 201 in the second waveguide 20.

[0044] When specifically setting each area 201 of the second waveguide 20, a plurality of mirrors 21 arranged in parallel are provided in each area 201, and the plurality of mirrors 21 are arranged at intervals along the length direction of the second waveguide 20. When specifically arranging the plurality of mirrors 21, the mirror 21 farthest from the coupling structure 30 is a reflective mirror 21, and the remaining mirrors 21 are partially transmissive and partially reflective mirrors 21. For the convenience of description, it is named the second partially transmissive and partially reflective mirror 21. When the control switch 40 corresponding to each area 201 is turned on, the light reflected by the first partially transmissive and partially reflective mirror corresponding to this area 201 can enter this area 201 through the control switch 40, and the light is transmitted and reflected by the second partially transmissive and partially reflective mirror 21 in the area 201. Among them, the reflected light can be coupled out of the second waveguide 20 and is used for the user to view. The transmitted light continues to propagate in the area 201 and is transmitted and reflected by the remaining second partially transmissive and partially reflective mirrors 21. Until the light propagates to the last mirror 21, the light is reflected out of the second waveguide 20 by this mirror 21, reducing the risk of the light in this area 201 propagating to the adjacent area 201.

[0045] In addition, for multiple areas, along the direction away from the coupling structure 30, the included angle between the mirrors 21 in the multiple areas 201 and the total internal reflection surface of the second waveguide 20 gradually increases. Taking Figure 2 the three areas 201 shown as an example, the three areas 201 are arranged along the direction away from the coupling structure 30, and are named the first area 201a, the second area 201b and the third area 201c respectively. Among them, the included angle between the mirror 21 in the first area 201a and the total internal reflection surface of the second waveguide 20 is the first included angle α, the included angle between the mirror 21 in the second area 201b and the total internal reflection surface of the second waveguide 20 is the second included angle β, and the included angle between the mirror 21 in the third area 201c and the total internal reflection surface of the second waveguide 20 is the third included angle γ. Then it satisfies: α < β < γ. It should be understood that in the embodiments of the present application, the included angle between the mirror 21 and the total internal reflection surface refers to the angle less than 90° among the two angles formed by the total internal reflection surface and the mirror 21.

[0046] Take the second waveguide 20 having a first region 201a, a second region 201b, and a third region 201c as an example. The light transmitted by the waveguide is parallel light, and parallel light at different angles corresponds to different regions 201 of the image. The light machine 100 controls the images of different regions 201 to enter the first waveguide 10 in sequence for propagation. Exemplarily, at time T1, when the light at an angle A1 enters the first waveguide 10, the control switch 40 corresponding to the first region 201a in the second waveguide 20 is in the on state, and the control switches 40 of the remaining regions 201 are in the off state. At time T2, the image of the second image region 201 enters the first waveguide 10 at an angle A2, and the control switch 40 corresponding to the second region 201b in the second waveguide 20 is in the on state, and the control switches 40 of the remaining regions 201 are in the off state; at time T3, the image of the third image region 201 enters the first waveguide 10 at an angle A3, and the control switch 40 corresponding to the third region 201c in the second waveguide 20 is in the on state, and the control switches 40 of the remaining regions 201 are in the off state. The time interval from T1 to Tn is very short. According to the visual persistence effect of the human eye, a complete image is formed in the human brain. Wherein, 1 to n are all natural numbers. And A1 < A2 < A3.

[0047] When the light is incident on the first waveguide 10 at angles A1, A2, and A3, since the larger the incident angle of the light, if the partially transmissive and partially reflective mirror 21 with the same tilt angle is still used to couple it out, the field of view angle of the coupled-out light is the same as the field of view angle of the light machine. When using mirrors 21 with different tilt angles, the angle of the mirror 21 can compensate for the angle of the coupled-out light (i.e., the field of view angle).

[0048] As Figure 4 shown, for easy understanding, take two mirrors 21 with different tilt angles as an example for illustration. One of the mirrors 21 forms an angle a1 with the total internal reflection surface, and the other mirror 21 forms an angle a2 with the total internal reflection surface, and a1 < a2. When a beam of parallel light is irradiated on the mirrors 21 with different tilt angles, the angle of the light reflected by the mirror 21 with a smaller angle with the total internal reflection surface is a3, and the angle of the light reflected by the mirror 21 with a larger angle with the total internal reflection surface is a4. Then a3 = 45° - a1, a4 = 45° - a2; since a1 < a2, then a3 > a4, that is, when the light is reflected by the light with a larger angle with the total internal reflection surface, the exit angle of the light (the angle between the exit light and the total internal reflection surface) is smaller and the inclination is larger. For the field of view angle, the two satisfy: the larger the tilt angle, the larger the field of view angle.

[0049] In the embodiments of the present application, the correspondence between the light incident angle and region 201 satisfies that the greater the incident angle of the light incident on the first waveguide 10, the greater the angle between the mirror 21 and the total internal reflection surface in region 201 of the second waveguide 20 where the light propagates.

[0050] As can be seen from the above description, when light rays with different incident angles enter the second waveguide 20, there are corresponding mirrors 21 with different angles. When coupling out from the second waveguide 20, due to the different tilt angles of the mirrors 21 in region 201 corresponding to light rays with different incident angles, different angle compensations will be given to these light rays, increasing the field of view angle.

[0051] Similarly, in the technical solution disclosed in the present application, by using mirrors 21 with different tilt angles in the second waveguide 20 corresponding to light rays with different incident angles, light rays within a larger viewing angle range can be reflected by the mirrors 21 in different regions 201 of the second waveguide 20 and converge into the user's pupil.

[0052] As can be seen from the above description, in the waveguide structure provided by the embodiments of the present application, by stacking two waveguide layers, where the first waveguide 10 is used to propagate light through total internal reflection, and the second waveguide 20 is used to couple out light through mirrors 21 with different tilt angles. Additionally, when the light propagates from the first waveguide 10 to the second waveguide 20, the switch 40 is used to control the light to enter different regions 201 of the second waveguide 20 layer, and mirrors 21 with different tilt angles are provided in different regions 201. Among them, when corresponding to region 201, the tilt angles of the mirrors 21 in region 201 corresponding to light rays incident on the first waveguide 10 at different incident angles are different, so as to compensate the exit angles of the light rays through the mirrors 21 with different tilt angles, so that different regions 201 of the image can be coupled out of the second waveguide 20 layer through the mirrors 21 in different regions of the second waveguide 20 layer and enter the user's through-hole, increasing the field of view angle of the waveguide structure.

[0053] In a specific feasible implementation, the first waveguide 10 and the second waveguide 20 are adhesively connected. For example, if the first waveguide 10 and the second waveguide 20 are adhesively connected through an adhesive layer, it satisfies that the refractive index of the first waveguide 10 is greater than the refractive index of the adhesive layer, and the refractive index of the second waveguide 20 is greater than the refractive index of the adhesive layer. When adhesively connecting in the above manner, a stable connection between the first waveguide 10 and the second waveguide 20 can be ensured, and at the same time, when the first waveguide 10 and the second waveguide 20 propagate light, total reflection can be used for propagation.

[0054] When specifically bonding through the bonding layer, different bonding methods can be adopted. In one example, in one method, the bonding layer is filled in the edge region 201 between the two waveguide layers, and the middle region 201 is air. That is, the part corresponding to the region 201 where total reflection occurs between the first waveguide 10 and the second waveguide 20 is air, which can ensure that total reflection occurs when light propagates in the first waveguide 10 or the second waveguide 20. Or in another solution, the bonding layer is filled in the edge or middle region 201 of the two waveguide layers. When light propagates in the first waveguide 10 or the second waveguide 20, since the refractive index of the bonding layer is less than that of the first waveguide 10 and the second waveguide 20, total reflection can also occur when light propagates in the first waveguide 10 or the second waveguide 20.

[0055] In a specific feasible implementation, the control switch 40 can be realized through polarization conversion. For example: the incident light is p-polarized. The open state of the control switch 40 in the region 201 corresponding to the incident light allows P-polarized light to pass through, while the switch state of the control switch 40 in the region 201 where coupling is not required can be controlled to allow S-polarized light to pass through. Then, at this time, the incident light that is p-polarized can only be incident in the corresponding region 201 and not enter the second waveguide 20 in other regions 201. The corresponding polarization of the above control switch 40 can be realized by means of voltage regulation.

[0056] Exemplarily, the control switch 40 provided in the embodiment of the present application includes a liquid crystal layer and a polarization film. Among them, the liquid crystal layer is located on the side close to the first waveguide 10, and the polarization film is located on the side close to the second waveguide 20. When in use, by applying a voltage to the liquid crystal layer, the arrangement mode of liquid crystal molecules can be changed, thereby changing the polarization state of light. For example: the light incident on the first waveguide 10 is P-linearly polarized light, and the polarization film of the control switch 40 allows S-linearly polarized light to pass through. At this time, if the polarization state of the light is not modulated by applying a voltage, the light cannot be coupled into the second waveguide 20. If a voltage is applied to the liquid crystal layer to modulate the polarization state of the light, only in the region 201 where coupling into the second waveguide 20 is required, the polarization state of the liquid crystal layer is modulated to modulate the light from P light to S light. At this time, the light can pass through the control switch 40 and be coupled into the second waveguide 20.

[0057] Continue to refer to Figure 2As shown, when specifically arranging the control switch 40, along the length direction of the second waveguide 20, the control switch 40 corresponding to each region 201 is located between the first mirror 21 in this region 201 and the last mirror 21 in the adjacent region 201. Taking the second region 201b as an example, its corresponding control switch 40 is located at one end close to the first region 201a on the upper edge of the second region 201b. That is, the control switch 40 corresponding to the second region 201b is located between the first mirror 21 in the second region 201b and the last mirror 21 in the first region 201a. When setting the control switch 40 in the above manner, taking the multiple mirrors 21 in each region 201 as a group of mirrors 21 as an example, then along the length direction of the second waveguide 20, the control switch 40 and multiple groups of mirrors 21 are alternately arranged. When arranging in the above manner, it can make the light entering the second waveguide 20 through the control switch 40 be reflected by all the mirrors 21.

[0058] When specifically setting the control switch 40, the control switch 40 can be made to correspond one by one with the first partial transmission and partial reflection mirrors. That is, each control switch 40 corresponds to a first partial transmission and partial reflection surface. That is, the light reflected by each first partial transmission and partial reflection mirror enters its corresponding region 201 through a corresponding control switch 40. Of course, in addition to the above corresponding manner, a control switch 40 array can also correspond to a first partial transmission and partial reflection surface, and its principle is the same as the principle of the control switch 40 described above, only the number of control switches 40 changes, so it will not be elaborated in detail here.

[0059] In an alternative solution, the division of the regions 201 in the second waveguide 20 can be adjusted according to requirements. For example, the sizes of different regions 201 can be the same or different. When it is necessary to adjust the aperture of the field-of-view light beam, the sizes of different regions 201 can be made different, so that the viewing range of a certain field-of-view image can be increased through the region 201 with a larger size. Similarly, the viewing range of a certain field-of-view image can also be reduced through the region 201 with a smaller size. That is, in the embodiments of the present application, the sizes in different regions 201 are determined according to the aperture required for the field-of-view image corresponding to this region 201, and the size of this aperture corresponds to the size of the region 201.

[0060] In an alternative solution, the aperture of the outgoing light beam can be effectively controlled by controlling the position and size of the region 201 and the tilt angle of the mirrors 21 arranged in the region 201, so that the outgoing light beams at different angles are concentrated at the same exit pupil position to increase the viewing angle range of the image observed by the user.

[0061] In an alternative solution, in the embodiments of the present application, the number of mirrors 21 in different regions 201 can be different or the same, so as to determine the number of mirrors 21 in this region 201 according to the image field of view corresponding to different regions 201.

[0062] In an optional embodiment, one mirror 21 in each region 201 of the embodiments of the present application that is farthest from the coupling structure 30 is a reflecting mirror, which can reduce the light in this region 201 from propagating to the adjacent region 201 and the ghost images formed by the reflection of the light by the mirrors 21 with different tilting angles in the adjacent region 201, thereby improving the display effect of the waveguide structure.

[0063] The embodiments of the present application also provide a near-eye display device, which includes an optical engine 100 and the waveguide structure of any one of the above; wherein, the light emitted by the optical engine 100 is coupled into the first waveguide 10 through the coupling structure 30. The near-eye display device provided by the embodiments of the present application transmits the light for displaying an image through the optical engine 100, and the light is coupled into the first waveguide 10 through the coupling structure 30 and then coupled out through the second waveguide 20. In the cooperation mode of the first waveguide 10 and the second waveguide 20, reference can be made to the detailed description of the above waveguide structure, which will not be elaborated here.

[0064] As can be seen from the above description, in the near-eye display device provided by the embodiments of the present application, the adopted waveguide structure stacks two waveguide layers, and controls the light to enter different regions 201 of the second waveguide 20 layer through the control switch 40, and mirrors 21 with different tilting angles are arranged in different regions 201, so that different regions 201 of the image can be coupled out of the second waveguide 20 layer through the mirrors 21 in different regions of the second waveguide 20 layer, increasing the viewing angle.

[0065] In a specific feasible embodiment, the near-eye display device provided by the embodiments of the present application further includes a control chip, and the control chip is used to control the opening and closing of the control switch 40 according to the corresponding relationship between the polarization state of the light and the region 201.

[0066] The embodiments of the present application also provide a usage method of a near-eye display device, and the near-eye display device is the near-eye display device of any one of the above; the method includes the following steps:

[0067] Step 001: Transmit the light for displaying an image through the optical engine 100;

[0068] Specifically, the light corresponding to the images of different regions 201 is sequentially transmitted through the optical engine 100. During specific use, the optical engine 100 transmits different fields in the image according to the time sequence. Specifically, reference can be made to the relevant descriptions in Figure 2 and Figure 3 for relevant descriptions.

[0069] Step 002: Propagate the light into the first waveguide 10 through the coupling structure 30 and reflect it to the control switch 40 through the first partial transmission and partial reflection mirror;

[0070] Specifically, light is totally reflected and propagated through the total internal reflection surface within the first waveguide 10, and part of the light is reflected by the first partial transmission and partial reflection mirror to couple out of the first waveguide 10. The coupled-out light irradiates the control switch 40 and enters the second waveguide 20 through the control of the control switch 40. For specific reference, see Figure 2 and Figure 3 description.

[0071] In the embodiment of the present application, the control switch 40 can control light through the polarization state of the light. For specific reference, see the description of the control switch 40 in the waveguide structure.

[0072] Step 003: Control the light to propagate to the corresponding area 201 in the second waveguide 20 through the control switch 40.

[0073] Specifically, determine the area 201 into which the light is to be incident according to the correspondence between the incident angle of the light incident on the first waveguide 10 and the area 201, and control the control switch 40 of this area 201 to be turned on, so that the light can enter this area 201 and the light is coupled out through the mirror 21 in this area 201.

[0074] In the above technical solution, by stacking two waveguide layers and controlling the light to enter different areas 201 of the second waveguide 20 layer through the control switch 40, and setting mirrors 21 with different tilt angles in different areas 201, different areas 201 of the image can be coupled out of the second waveguide 20 layer through the mirrors 21 in different areas of the second waveguide 20 layer, thus increasing the field of view angle.

[0075] One or more embodiments of this specification are intended to cover all such substitutions, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of one or more embodiments of this specification shall be included within the protection scope of this disclosure.

[0076] The above is only the specific implementation manner of this application, but the protection scope of this application is not limited thereto. Any person skilled in the art within the technical scope disclosed by this application can easily think of changes or substitutions, which should all be covered within the protection scope of this application. Therefore, the protection scope of this application shall be subject to the protection scope of the claims.

Claims

1. A waveguide structure, characterized in that, It includes a stacked first waveguide and a second waveguide; wherein, a coupling-in structure is provided on the first waveguide; A plurality of first partially transmissive and partially reflective mirrors arranged at intervals and inclined are provided in the first waveguide; Along the length direction of the second waveguide, the inside of the second waveguide is divided into regions corresponding to each first partially transmissive and partially reflective mirror; a plurality of parallel mirrors are provided in each region, wherein the mirror farthest from the coupling-in structure is a reflective mirror, and the remaining mirrors are second partially transmissive and partially reflective mirrors; along the direction away from the coupling-in structure, the angle between the mirrors in multiple regions and the total internal reflection surface of the second waveguide gradually increases; A control switch corresponding to each region is provided between the first waveguide and the second waveguide. When any control switch is turned on, light can propagate from the first waveguide into the corresponding region in the second waveguide and be coupled out through the multiple mirrors in this region.

2. The waveguide structure according to claim 1, characterized in that, The control switch includes a liquid crystal layer and a polarizing film; wherein, When the liquid crystal layer is powered on, the control switch can transmit light of the first polarization state; When the liquid crystal layer is not powered on, the control switch can transmit light of the second polarization state.

3. The waveguide structure according to claim 2, characterized in that, Along the length direction of the second waveguide, the control switch corresponding to each region is located between the first mirror in this region and the last mirror in the adjacent region.

4. The waveguide structure according to claim 3, characterized in that The control switch corresponds to the first partially transmissive and partially reflective mirror one by one.

5. The waveguide structure according to claim 2, wherein Along the length direction of the second waveguide, the lengths of any two of the regions may be equal.

6. The waveguide structure according to any one of claims 1 to 5, characterized in that, The first waveguide and the second waveguide are adhesively connected through an adhesive layer; wherein, The refractive index of the first waveguide is greater than that of the adhesive layer, and the refractive index of the second waveguide is greater than that of the adhesive layer.

7. A near-eye display device, characterized in that, It includes an optical engine and the waveguide structure according to any one of claims 1 to 6; wherein, The light emitted by the optical engine is coupled into the first waveguide through the coupling-in structure.

8. The near-eye display device according to claim 7, wherein, The near-eye display device further includes a control chip, and the control chip is used to control the opening and closing of the control switch according to the corresponding relationship between the polarization state of light and the region.

9. A method of using a near-eye display device, characterized in that, The near-eye display device is the near-eye display device according to claim 7 or 8; the method includes the following steps: Emitting light for displaying an image through an optical engine; Propagating the light into the first waveguide through the coupling-in structure and reflecting it to the control switch through the first partially transmissive and partially reflective mirror; Controlling the light to propagate into the corresponding region in the second waveguide through the control switch.

10. The method according to claim 9, wherein The emitting light for displaying an image through an optical engine; specifically: Sequentially sending the light corresponding to the images of different regions through the optical engine.

Images