A display module with liquid crystal switch and AR device

Abstract

The present application provides a display module and AR device with a liquid crystal switch, which relates to the field of optical display technology. The liquid crystal switch unit is set in a control area on the surface of the optical waveguide in a non-embedded manner, so that the processing and fixing process are simpler, and the impact on the internal structure of the optical waveguide is also reduced, ensuring the transmission stability and consistency of light. In addition, the liquid crystal switch unit is located on the optical path between the coupling-in area and the coupling-out area. When the liquid crystal switch unit is in a first state, the light emitted by the optical machine can be adjusted to be transmitted to the outside of the optical waveguide in the control area. When the liquid crystal switch unit is in a second state, the light emitted by the optical machine can be adjusted to be totally reflected in the control area. Therefore, by accurately controlling the state of the liquid crystal switch unit, it is possible to achieve precise control of the imaging effect, reduce the generation of stray light during the imaging process, and improve the clarity and brightness of the picture.

Description

Technical Field

[0001] The present application relates to the field of optical display technology, and in particular, to a display module and an AR device with a liquid crystal switch. Background Art

[0002] With the advancement of imaging technology, people's demand for immersive experience is getting higher and higher. Virtual Reality (VR) and Augmented Reality (AR) technologies have emerged, gradually satisfying people's pursuit of visual experience. In VR or AR scenarios, users can wear a head-mounted device, which consists of an integrated graphics system, optical system and posture tracking system, and can provide an interactive immersive experience for the user of the device. Among them, unlike VR head-mounted devices that block the external environment, AR head-mounted devices can combine virtual information with the real world to enhance the user's reality perception experience.

[0003] Most of the existing AR head-mounted devices use a dual-optical machine configuration to achieve 3D imaging, but the dual-optical machine has complicated steps to assemble because the resulting image needs to be calibrated, which is time-consuming and has a low yield, making it unfavorable for mass production. In response to the above problems, a small number of AR head-mounted devices equipped with a single-optical machine have begun to appear. This type of device only needs to set up a single-optical machine and set two liquid crystal switches and polarizers in the optical waveguide to achieve 3D effect imaging in the human eye, reducing the difficulty of installation and calibration and saving costs. However, the overall processing of the equipment is difficult, and it is easy to generate stray light due to the position deviation of the liquid crystal switch and the polarizer, which reduces the brightness of the imaging picture and causes blurred images in some areas. Utility Model Content

[0004] The purpose of this application is to provide a display module and AR device with a liquid crystal switch to address the deficiencies in the above-mentioned technology.

[0005] To achieve the above purpose, the technical solution adopted in the embodiment of the present application is as follows:

[0006] In one aspect of an embodiment of the present application, a display module with a liquid crystal switch is provided, including an optical machine and an optical waveguide located on the light output side of the optical machine, the optical waveguide having a coupling-in area and a coupling-out area, a non-embedded liquid crystal switch unit is arranged in a control area on the surface of the optical waveguide, the liquid crystal switch unit is located on the optical path between the coupling-in area and the coupling-out area, and the liquid crystal switch unit has a first state for adjusting the transmission of light emitted by the optical machine in the control area and a second state for adjusting the total reflection of the light in the control area.

[0007] Optionally, the liquid crystal switch unit includes a first liquid crystal switch and a second liquid crystal switch, the outcoupling region includes a first outcoupling region and a second outcoupling region, the first liquid crystal switch is located on the optical path between the incoupling region and the first outcoupling region, and the second liquid crystal switch is located on the optical path between the incoupling region and the second outcoupling region.

[0008] Optionally, the working states of the first liquid crystal switch and the second liquid crystal switch are opposite; when the optical machine emits odd-numbered frames of light, the first liquid crystal switch is in the second state, and the odd-numbered frames of light are emitted through the first outcoupling area to the left eye for imaging; when the optical machine emits even-numbered frames of light, the second liquid crystal switch is in the second state, and the even-numbered frames of light are emitted through the second outcoupling area to the right eye for imaging.

[0009] Optionally, the liquid crystal switch unit is located on a surface of the optical waveguide close to the optical machine.

[0010] Optionally, the optical waveguide further has a first turning region, which is located between the liquid crystal switch unit and the outcoupling region. When the liquid crystal switch unit is in the second state, the light coupled in through the coupling region is dilated through the first turning region and then coupled out through the outcoupling region.

[0011] Optionally, the optical waveguide further has a second turning region, which is located between the coupling-in region and the liquid crystal switch unit, and the light coupled in through the coupling-in region is incident on the liquid crystal switch unit after the pupil is expanded through the second turning region.

[0012] Optionally, the display module with a liquid crystal switch further includes a controller, and the controller is electrically connected to the optical machine and the liquid crystal switch unit respectively.

[0013] Optionally, the coupling-in region is provided with an coupling-in grating, and the coupling-out region is provided with an coupling-out grating.

[0014] Optionally, the optical engine includes LCOS, DLP or Micro-LED.

[0015] In another aspect of an embodiment of the present application, an AR device is provided, including a wearable component and any one of the above-mentioned display modules with liquid crystal switches, wherein the wearable component is connected to an optical waveguide of the display module with the liquid crystal switch.

[0016] The beneficial effects of this application include:

[0017] The present application provides a display module and AR device with a liquid crystal switch, including an optical machine and an optical waveguide located on the light output side of the optical machine, the optical waveguide having an incoupling region and an outcoupling region, a non-embedded liquid crystal switch unit is arranged in the control region on the surface of the optical waveguide, the liquid crystal switch unit is located on the optical path between the incoupling region and the outcoupling region, and the liquid crystal switch unit has a first state for adjusting the transmission of the light emitted by the optical machine in the control region and a second state for adjusting the total reflection of the light in the control region. The present application arranges the liquid crystal switch unit in the control region on the surface of the optical waveguide in a non-embedded manner, so that the processing and fixing process are simpler, and the influence on the internal structure of the optical waveguide is also reduced, ensuring the transmission stability and consistency of the light. In addition, the liquid crystal switch unit is located on the optical path between the incoupling region and the outcoupling region, so that when the liquid crystal switch unit is in the first state, the light emitted by the optical machine can be adjusted to be transmitted to the outside of the optical waveguide in the control region, and when the liquid crystal switch unit is in the second state, the light emitted by the optical machine can be adjusted to be totally reflected in the control region, that is, the light continues to propagate inside the optical waveguide and is emitted through the outcoupling region to the human eye for imaging. Therefore, by precisely controlling the state of the liquid crystal switch unit, the transmission and total reflection of light can be effectively adjusted, thereby achieving precise control of the imaging effect, reducing the generation of stray light during the imaging process, improving the clarity and brightness of the picture, and enhancing the user experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 One of the structural schematic diagrams of a display module with a liquid crystal switch provided in an embodiment of the present application;

[0020] Figure 2 A second structural schematic diagram of a display module with a liquid crystal switch provided in an embodiment of the present application;

[0021] Figure 3 One of the optical path diagrams of light propagating in the optical waveguide when the first liquid crystal switch is in the second state and the second liquid crystal switch is in the first state provided in an embodiment of the present application;

[0022] Figure 4 A light path diagram of light propagating in an optical waveguide when a first liquid crystal switch is in a first state and a second liquid crystal switch is in a second state provided in an embodiment of the present application;

[0023] Figure 5A light path diagram of light propagating in an optical waveguide when a liquid crystal switch unit provided in an embodiment of the present application is in a first state;

[0024] Figure 6 A light path diagram of light propagating in an optical waveguide when a liquid crystal switch unit provided in an embodiment of the present application is in a second state;

[0025] Figure 7 A second optical path diagram of light propagating in an optical waveguide when a first liquid crystal switch is in a second state and a second liquid crystal switch is in a first state provided in an embodiment of the present application;

[0026] Figure 8 The third structural schematic diagram of a display module with a liquid crystal switch provided in an embodiment of the present application;

[0027] Fig. 9 The fourth structural schematic diagram of a display module with a liquid crystal switch provided in an embodiment of the present application.

[0028] Icon: 1-optical machine; 2-optical waveguide; 21-coupling region; 22-outcoupling region; 221-first outcoupling region; 222-second outcoupling region; 23-first turning region; 24-second turning region; 3-liquid crystal switch unit; 31-first liquid crystal switch; 32-second liquid crystal switch. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0030] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for protection, but merely represents selected embodiments of the present application. It should be noted that, in the absence of conflict, the various features in the embodiments of the present application can be combined with each other, and the combined embodiments are still within the scope of protection of the present application.

[0031] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0032] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the product of the application is usually placed when in use. They are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0033] In addition, the terms "horizontal", "vertical" and the like do not mean that the components are required to be absolutely horizontal or suspended, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0034] In the description of this application, it should also be noted that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" 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 it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0035] At present, most AR head-mounted devices use a dual-optical machine configuration to achieve 3D imaging. However, there are a series of problems in the assembly process of the dual-optical machine: cumbersome steps, long calibration time, high cost, and low production efficiency. In response to these challenges, some AR head-mounted devices with a single-optical machine configuration have begun to appear. This type of device only needs to set up a single-optical machine and place two liquid crystal switches and polarizers in the optical waveguide to achieve 3D effect imaging in the human eye, which reduces the difficulty of installation and calibration and saves costs. However, this configuration also has some problems. First, the overall processing difficulty of the equipment increases because the setting of the liquid crystal switch and the polarizer requires more sophisticated processes. Secondly, due to slight deviations in the position of the liquid crystal switch and the polarizer, stray light is easily generated, resulting in reduced brightness of the imaging screen and blurred areas.

[0036] In view of the above problems, one aspect of the embodiments of the present application provides a display module with a liquid crystal switch, such as Figures 1 to 4As shown, the display module with a liquid crystal switch includes an optical machine 1 and an optical waveguide 2 located on the light output side of the optical machine 1, the optical waveguide 2 having a coupling-in region 21 and a coupling-out region 22, a non-embedded liquid crystal switch unit 3 is arranged in a control region on the surface of the optical waveguide 2, the liquid crystal switch unit 3 is located on the optical path between the coupling-in region 21 and the coupling-out region 22, and the liquid crystal switch unit 3 has a first state for adjusting the transmission of light emitted by the optical machine 1 in the control region and a second state for adjusting the total reflection of light in the control region.

[0037] Specifically, by adopting a non-embedded manner to set the liquid crystal switch unit 3 in the control area on the surface of the optical waveguide 2, the complex embedded structure design and manufacturing process can be avoided, making its processing and fixing process simpler, while also reducing the impact on the internal structure of the optical waveguide 2, ensuring the transmission stability and consistency of the light. In addition, the liquid crystal switch unit 3 is located on the optical path between the coupling-in area 21 and the coupling-out area 22, so that the light emitted by the optical machine 1 is first coupled into the inside of the optical waveguide 2 through the coupling-in area 21. When the liquid crystal switch unit 3 is in the first state, the light control area can be adjusted to be transmitted to the outside of the optical waveguide 2. When the liquid crystal switch unit 3 is in the second state, the light can be adjusted to be totally reflected in the control area, that is, the light continues to propagate inside the optical waveguide 2 and is emitted through the coupling-out area 22 to the human eye for imaging. Therefore, by accurately controlling the state of the liquid crystal switch unit 3, the transmission and total reflection of the light can be effectively adjusted, thereby achieving precise control of the imaging effect, and reducing the generation of stray light during the imaging process, improving the clarity and brightness of the picture, and enhancing the user experience.

[0038] It should be noted that the liquid crystal switch unit 3 can be located on the surface of the optical waveguide 2 away from the optical machine 1, or on the surface of the optical waveguide 2 close to the optical machine 1. When the liquid crystal switch unit 3 is in the first state, when the liquid crystal switch unit 3 is located on the surface of the optical waveguide 2 away from the optical machine 1, the light emitted by the optical machine 1 will be transmitted in the control area to the direction away from the optical machine 1, and when the liquid crystal switch unit 3 is located on the surface of the optical waveguide 2 close to the optical machine 1, the light emitted by the optical machine 1 will be transmitted in the control area to the direction of the optical machine 1. According to the arrangement of the liquid crystal switch unit 3 on the surface of the optical waveguide 2, shading measures should be taken on the corresponding light transmission path, such as coating a shading layer, to prevent stray light from affecting the imaging quality. When the liquid crystal switch unit 3 is in the second state, the liquid crystal switch unit 3 arranged on the surface of the optical waveguide 2 away from the optical machine 1 or close to the optical machine 1 will cause the light emitted by the optical machine 1 to be totally reflected in the control area to the human eye for imaging. Preferably, the liquid crystal switch unit 3 is located on the surface of the optical waveguide 2 close to the optical machine 1. As a result, the transmission direction of the light when the liquid crystal switch unit 3 is in the first state is opposite to the total reflection direction of the light when the liquid crystal switch unit 3 is in the second state, which can further reduce the influence of the transmitted light on the imaging quality.

[0039] It should also be noted that the liquid crystal switch unit 3 and the optical waveguide 2 can be made in an integrated manner. By directly integrating the liquid crystal switch unit 3 into the structure of the optical waveguide 2, the complex assembly process and the additional docking process are avoided, making the entire optical system more compact, reducing costs, and reducing possible assembly errors and assembly difficulties. In addition, the integrated design makes the connection between the liquid crystal switch unit 3 and the optical waveguide 2 tighter, reduces possible gaps and cracks, effectively prevents the leakage and leakage of light, reduces the generation of stray light, reduces interference and noise in the image, and improves the clarity and contrast of the image, so that users can obtain a clearer, more realistic and comfortable image display effect, and enhances the overall visual experience. More importantly, by removing the structure that realizes the 3D function from the inside of the optical machine 1, the optical machine 1 can be simplified and streamlined. Such a design can not only effectively reduce the volume of the optical machine 1, improve wearing comfort and portability, but also reduce manufacturing costs, and reduce possible failure points and maintenance difficulties, thereby achieving a simpler and more efficient 3D imaging function.

[0040] Optionally, the coupling-in region 21 is provided with a coupling-in grating, and the coupling-out region 22 is provided with a coupling-out grating.

[0041] Specifically, the coupling-in grating is located in the coupling-in region 21, and its main function is to couple the light emitted by the optical machine 1 into the optical waveguide 2 for propagation. By designing a suitable coupling-in grating, the light can be successfully coupled into the optical waveguide 2 after being diffracted by the coupling-in grating. A refractive index difference is formed inside and outside the optical waveguide 2, so that the light can be propagated by total reflection, thereby ensuring the stable transmission of the light inside the optical waveguide 2. The coupling-out grating is located in the coupling-out region 22, and its main function is to couple the light inside the optical waveguide 2 out of the optical waveguide 2 and propagate it to the human eye to complete imaging. Through the appropriate design of the coupling-out grating, the light can be smoothly coupled out of the optical waveguide 2 and propagate to the human eye to complete the imaging function of the image. The coupling-in grating and the coupling-out grating can be surface relief gratings or volume holographic gratings.

[0042] Optionally, the display module with a liquid crystal switch further includes a controller, and the controller is electrically connected to the optical engine 1 and the liquid crystal switch unit 3 respectively.

[0043] Specifically, in addition to the optical waveguide 2 and the liquid crystal switch unit 3, the display module also includes a controller for managing the operation of the optical machine 1 and the liquid crystal switch unit 3. The controller is electrically connected to the optical machine 1 and the liquid crystal switch unit 3, respectively, to ensure that they can operate in the expected manner. Among them, the liquid crystal switch unit 3 is one of the core components of the display module and is mainly composed of liquid crystal. Liquid crystal is a birefringent crystal, that is, a crystal with two refractive indices. By applying different electric field directions to the liquid crystal switch unit 3 by the controller, the arrangement of the liquid crystal molecules can be changed, so that the liquid crystal switches between the two refractive indices. This switching causes the liquid crystal to produce different directions of refraction deflection for light in the same direction, thereby achieving precise control of the light. By controlling the electric field direction of the liquid crystal switch unit 3, the refractive index of the liquid crystal can be adjusted, thereby achieving the effect of controlling the transmission or total reflection of light.

[0044] The principle of controlling light transmission or total reflection when the liquid crystal switch unit 3 is in different states is as follows: Figure 5 and Figure 6 As shown, the light emitted by the optical machine 1 is coupled into the optical waveguide 2 through the coupling region 21 and propagates inside the optical waveguide 2. After passing through the coupling grating, the light is totally reflected and propagates inside the optical waveguide 2. When reaching the liquid crystal switch unit 3, the liquid crystal switch unit 3 has two states, namely, the first state and the second state. The controller outputs different voltages to the liquid crystal switch unit 3, thereby changing the state of the liquid crystal switch unit 3, that is, the refractive index of the incident light changes, thereby changing the state of the light. Specifically, as shown in the following three formulas:

[0045] The diffraction formula of light in the coupling-in region 21 is: sinθ=n1sinθ1-λ / d1;

[0046] When the liquid crystal switch unit 3 is in the first state, the light transmission formula is: n1sinθ1=n e sinθ2≤n e ;

[0047] When the liquid crystal switch unit 3 is in the second state, the total reflection formula of the light is: n1sinθ1=n o sinθ2≥n o .

[0048] Wherein, θ is the incident angle of the light, θ1 is the diffraction angle of the light after passing through the coupling region 21, θ2 is the angle of the light after passing through the liquid crystal switch unit 3, n1 is the refractive index of the optical waveguide 2, λ is the wavelength of the incident light, d1 is the coupling grating period in the coupling region 21, n e is the first refractive index of the liquid crystal switch unit 3 when it is in the first state, n o is the second refractive index when the liquid crystal switch unit 3 is in the second state.

[0049] The diffraction angle of the light after passing through the coupling region 21 is obtained according to the diffraction formula of the light in the coupling region 21, and the relationship between the refractive index of the optical waveguide 2 and the refractive index of the liquid crystal switch unit 3 can be obtained by combining the transmission formula and the total reflection formula of the light when the liquid crystal switch unit 3 is in different states: n o ≤n1sinθ1≤n e As long as the refractive index of the optical waveguide 2 and the refractive index of the liquid crystal switch unit 3 satisfy this relationship, and different voltages are applied to the liquid crystal switch unit 3 by the controller to control the first refractive index and the second refractive index, and the state switching of the liquid crystal switch unit 3 is completed, the precise control of the light by the liquid crystal switch unit 3 can be achieved. It should be understood that the switching of the first refractive index and the second refractive index is manifested as the change of the arrangement direction of the liquid crystal molecules at the microscopic level. After the arrangement direction of the liquid crystal molecules is changed, the refractive index for the incident light in the same direction is different, so that the light propagating from the coupling-in area 21 continues to be totally reflected or transmitted to the outside of the optical waveguide 2.

[0050] Optionally, the liquid crystal switch unit 3 includes a first liquid crystal switch 31 and a second liquid crystal switch 32, the outcoupling region 22 includes a first outcoupling region 221 and a second outcoupling region 222, the first liquid crystal switch 31 is located on the optical path between the coupling region 21 and the first outcoupling region 221, and the second liquid crystal switch 32 is located on the optical path between the coupling region 21 and the second outcoupling region 222.

[0051] Specifically, Figure 3 and Figure 4 As shown, the liquid crystal switch unit 3 includes a first liquid crystal switch 31 and a second liquid crystal switch 32, which play a key role in the entire display module. At the same time, the outcoupling area 22 is also subdivided into a first outcoupling area 221 and a second outcoupling area 222 to achieve more precise light control. The first liquid crystal switch 31 is located on the optical path between the coupling-in area 21 and the first outcoupling area 221, while the second liquid crystal switch 32 is located on the optical path between the coupling-in area 21 and the second outcoupling area 222. Therefore, after the light is coupled into the optical waveguide 2 through the coupling-in area 21, it can be adjusted by the first liquid crystal switch 31 in the second state and then emitted through the first outcoupling area 221 to the human eye for imaging, and adjusted by the second liquid crystal switch 32 in the second state and then emitted through the second outcoupling area 222 to the human eye for imaging. This partition design allows the liquid crystal switch unit 3 to independently adjust the transmission and total reflection states of the light as needed, thereby achieving fine control of the imaging effect. This design not only simplifies the assembly and calibration process, but also improves the imaging effect and product stability.

[0052] It should be noted that the shapes of the first liquid crystal switch 31 and the second liquid crystal switch 32 can be flexible and are not strictly limited. Figures 7 to 9As shown, they can adopt various shapes, such as a cuboid, a triangular prism, a cylinder, etc., to meet different design and installation requirements. In addition, the first liquid crystal switch 31 and the second liquid crystal switch 32 can also be set at a certain inclination angle to the horizontal, and such a design is not strictly limited. By flexibly designing the shape and angle of the liquid crystal switch unit 3, the structure and assembly requirements of different AR devices can be better adapted. For example, when designing AR glasses, it may be necessary to design the liquid crystal switch unit 3 into a smaller shape so that it can be better installed on the glasses frame. In other AR devices, the shape and angle of the liquid crystal switch unit 3 may be adjusted according to the overall design and functional requirements of the device.

[0053] Optionally, the working states of the first liquid crystal switch 31 and the second liquid crystal switch 32 are opposite; when the optical machine 1 emits odd-numbered frames of light, the first liquid crystal switch 31 is in the second state, and the odd-numbered frames of light are emitted through the first outcoupling area 221 to the left eye for imaging; when the optical machine 1 emits even-numbered frames of light, the second liquid crystal switch 32 is in the second state, and the even-numbered frames of light are emitted through the second outcoupling area 222 to the right eye for imaging.

[0054] Specifically, by setting the working states of the first liquid crystal switch 31 and the second liquid crystal switch 32 to be opposite, this design ensures that the light is processed differently in the two outcoupling regions 22. Figure 3 As shown, when the optical machine 1 emits odd-numbered frames of light, the second liquid crystal switch 32 is in the first state, and the first liquid crystal switch 31 is in the second state. At this time, the odd-numbered frames of light propagating to the second outcoupling area 222 will be transmitted to the outside of the optical waveguide 2 and cannot be imaged in the right eye, while the odd-numbered frames of light propagating to the first outcoupling area 221 can be normally fully reflected and propagated, and emitted to the left eye through the first outcoupling area 221, forming an image with left parallax. Figure 4 As shown, when the optical machine 1 emits an even-numbered frame of light, the first liquid crystal switch 31 is in the first state, and the second liquid crystal switch 32 is in the second state. At this time, the even-numbered frame of light propagating to the first outcoupling area 221 will be transmitted to the outside of the optical waveguide 2 and cannot be imaged in the left eye, while the even-numbered frame of light propagating to the second outcoupling area 222 can be normally fully reflected and propagated, and emitted to the right eye through the second outcoupling area 222, forming an image with right parallax. This frame processing method effectively realizes the separation of left and right eye imaging, that is, the images with different parallaxes are output to the left and right eyes by time-sharing, and finally a 3D image with depth information is formed after being processed by the brain, bringing a more immersive and realistic viewing experience to the user. At the same time, the coordination of the odd and even frame light emitted by the optical machine 1 and the state of the liquid crystal switch unit 3 ensures the accuracy and stability of the imaging effect. This sophisticated light control scheme greatly improves the imaging effect and user experience of the display module.

[0055] Optionally, the working states of the first liquid crystal switch 31 and the second liquid crystal switch 32 are opposite; when the optical machine 1 emits odd-numbered frames of light, the second liquid crystal switch 32 is in the second state, and the odd-numbered frames of light are emitted to the right eye through the second outcoupling area 222 for imaging; when the optical machine 1 emits even-numbered frames of light, the first liquid crystal switch 31 is in the second state, and the even-numbered frames of light are emitted to the left eye through the first outcoupling area 221 for imaging. Thus, when the optical machine 1 emits odd-numbered frames of light, the first liquid crystal switch 31 is in the first state, and the second liquid crystal switch 32 is in the second state. At this time, the odd-numbered frames of light propagating to the first outcoupling area 221 will be transmitted to the outside of the optical waveguide 2 and cannot be imaged in the left eye, while the odd-numbered frames of light propagating to the second outcoupling area 222 can be normally totally reflected and propagated, and emitted to the right eye through the second outcoupling area 222, forming an image with right parallax. When the optical machine 1 emits an even-numbered frame of light, the second liquid crystal switch 32 is in the first state, and the first liquid crystal switch 31 is in the second state. At this time, the even-numbered frame of light propagating to the second outcoupling area 222 will be transmitted to the outside of the optical waveguide 2 and cannot form an image in the right eye, while the even-numbered frame of light propagating to the first outcoupling area 221 can be normally totally reflected and propagated, and emitted to the left eye through the first outcoupling area 221, forming an image with left parallax.

[0056] It should be noted that in order to achieve time-sharing output of images with different parallaxes to the left and right eyes, the optical machine 1 needs to be able to adapt to different frame image requirements. This usually involves the image processing and control system inside the optical machine 1. For example, for each frame of image, the optical machine 1 needs to be able to generate corresponding left-eye and right-eye parallax images according to the set rules, and ensure that they are output to the corresponding eyes at the right time.

[0057] Optionally, the optical engine 1 includes LCOS, DLP or Micro-LED.

[0058] Specifically, common optical machines 1 include LCOS (liquid crystal microdisplay), Fast-LCD (fast liquid crystal display), DLP (digital micromirror component), Micro-LED (micro light emitting diode), Mini-LED (millimeter light emitting diode) and Micro-OLED (micro organic light emitting diode), etc.

[0059] Among them, LCOS technology is based on the principle of liquid crystal display and uses liquid crystal microdisplay to generate images. It has the advantages of high resolution and good color performance, and is suitable for AR application scenarios that require high clarity and color reproduction.

[0060] Fast-LCD is a display based on liquid crystal technology, which is characterized by fast response speed and the ability to quickly refresh image content. It has the advantages of rich colors and high resolution, and is suitable for scenes that require high-quality image display. In AR head-mounted devices, Fast-LCD is often used to achieve high-definition and realistic virtual images.

[0061] DLP technology uses micro-mirror components to control the reflection of light to achieve image display. It has the advantages of high brightness, high contrast and fast response speed, and is suitable for AR scenes that require high brightness and dynamic image display.

[0062] Micro-LED technology uses micro light-emitting diodes to achieve image display. It has the characteristics of small pixels, low energy consumption and high contrast. It is suitable for AR application scenarios that require high energy efficiency and high contrast.

[0063] Mini-LED is a new type of display technology that uses a smaller LED backlight module with higher brightness and contrast, as well as a wider color gamut. Mini-LED displays can provide brighter, clearer and more realistic image effects in AR devices.

[0064] Micro-OLED is a light-emitting diode made of organic materials, with extremely high pixel density and color saturation, as well as fast response speed. Micro-OLED displays can achieve high-resolution, high-contrast and low-power image display in AR devices, and are suitable for application scenarios requiring high image quality and low latency.

[0065] In specific applications, different types of optical machines 1 can be selected to achieve AR display according to specific needs and application scenarios. These different optical machine 1 technologies can provide users with high-quality visual experience, and also provide diverse choices and possibilities for the development of AR technology.

[0066] Optionally, the optical waveguide 2 further has a first turning region 23, which is located between the liquid crystal switch unit 3 and the outcoupling region 22. When the liquid crystal switch unit 3 is in the second state, the light coupled in through the coupling region 21 is dilated through the first turning region 23 and then coupled out through the outcoupling region 22.

[0067] Specifically, Figure 7 and Figure 8As shown, in the optical waveguide 2, in addition to the liquid crystal switch unit 3 and the out-coupling area 22, a first turning area 23 can also be set. The function of the first turning area 23 is to expand the pupil, that is, to expand the range of the image from another dimension, so that the imaging range is larger, thereby improving the user's visual experience. Specifically, the first turning area 23 can bend the light or change the propagation direction during the transmission process, so as to transmit the image from the optical waveguide 2 to the position of the eye. In this way, even if the overall size of the device is small, the clarity and field of view of the image can be maintained, providing a satisfactory viewing experience. The first turning area 23 is set between the liquid crystal switch unit 3 and the out-coupling area 22, so that when the liquid crystal switch unit 3 is in the second state, the light coupled into the coupling area 21 is first totally reflected in the control area, and after the pupil is expanded through the first turning area 23, it is transmitted to the human eye through the out-coupling area 22 to complete a clear imaging effect. Therefore, under the premise of outputting the same size of the picture, the volume of the optical machine 1 can be smaller and more suitable for assembly on a small AR device, such as AR glasses. It should be noted that when the outcoupling region 22 includes the first outcoupling region 221 and the second outcoupling region 222, there should also be two first turning regions 23, and the two first turning regions 23 are used to expand the light propagating to the first outcoupling region 221 and the light propagating to the second outcoupling region 222 respectively.

[0068] Alternatively, if Fig. 9 As shown, the optical waveguide 2 also has a second turning region 24, which is located between the coupling region 21 and the liquid crystal switch unit 3, and its function is to adjust the path of the incident light, so that the light coupled in through the coupling region 21 is incident on the liquid crystal switch unit 3 after the pupil is expanded by the second turning region 24. Specifically, when the liquid crystal switch unit 3 includes a first liquid crystal switch 31 and a second liquid crystal switch 32, and the coupling-out region 22 includes a first coupling-out region 221 and a second coupling-out region 222, there are also two second turning regions 24. When the light emitted by the optical machine 1 is coupled into the optical waveguide 2 through the coupling-in region 21 and propagates inside, based on the symmetry of diffraction, the light will be divided into two paths and propagate simultaneously. Therefore, after turning through the corresponding second turning region 24, the light will propagate toward the first liquid crystal switch 31 and the second liquid crystal switch 32. In this process, one of the first liquid crystal switch 31 and the second liquid crystal switch 32 is in the first state, and the other is in the second state. Therefore, only one of the light rays can reach the corresponding coupling-out region 22 and couple out of the optical waveguide 2 to form an image. In the next frame of image, the states of the two liquid crystal switches are opposite, so that another path of light can reach another outcoupling area 22 for imaging. Through such alternating operations, a 3D image with depth information is finally formed.

[0069] In another aspect of the embodiment of the present application, an AR device is provided, comprising a wearable component and any of the above-mentioned display modules with liquid crystal switches, wherein the wearable component is connected to the optical waveguide 2 of the display module with the liquid crystal switch to achieve image transmission and display. The AR device includes the same beneficial effects as the display module with the liquid crystal switch in the aforementioned embodiment. The beneficial effects of the display module with the liquid crystal switch have been described in detail in the aforementioned embodiment and will not be repeated here.

[0070] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A display module with a liquid crystal switch, characterized in that: The invention comprises an optical machine (1) and an optical waveguide (2) located on the light output side of the optical machine (1), wherein the optical waveguide (2) has an incoupling region (21) and an outcoupling region (22), a non-embedded liquid crystal switch unit (3) is arranged in a control region on the surface of the optical waveguide (2), the liquid crystal switch unit (3) is located on the optical path between the incoupling region (21) and the outcoupling region (22), and the liquid crystal switch unit (3) has a first state for adjusting the transmission of light emitted by the optical machine (1) in the control region and a second state for adjusting the total reflection of the light in the control region.

2. The display module with a liquid crystal switch according to claim 1, characterized in that: The liquid crystal switch unit (3) comprises a first liquid crystal switch (31) and a second liquid crystal switch (32); the outcoupling region (22) comprises a first outcoupling region (221) and a second outcoupling region (222); the first liquid crystal switch (31) is located on an optical path between the incoupling region (21) and the first outcoupling region (221); and the second liquid crystal switch (32) is located on an optical path between the incoupling region (21) and the second outcoupling region (222).

3. The display module with a liquid crystal switch according to claim 2, characterized in that: The working states of the first liquid crystal switch (31) and the second liquid crystal switch (32) are opposite; when the optical machine (1) emits odd-numbered frames of light, the first liquid crystal switch (31) is in a second state, and the odd-numbered frames of light are emitted through the first outcoupling area (221) to form an image for the left eye; when the optical machine (1) emits even-numbered frames of light, the second liquid crystal switch (32) is in a second state, and the even-numbered frames of light are emitted through the second outcoupling area (222) to form an image for the right eye.

4. The display module with a liquid crystal switch according to any one of claims 1 to 3, characterized in that: The liquid crystal switch unit (3) is located on the surface of the optical waveguide (2) on a side close to the optical engine (1).

5. The display module with a liquid crystal switch according to any one of claims 1 to 3, characterized in that: The optical waveguide (2) further comprises a first turning region (23), wherein the first turning region (23) is located between the liquid crystal switch unit (3) and the outcoupling region (22), and when the liquid crystal switch unit (3) is in a second state, the light coupled in through the coupling-in region (21) is dilated through the first turning region (23) and then coupled out through the outcoupling region (22).

6. The display module with a liquid crystal switch according to any one of claims 1 to 3, characterized in that: The optical waveguide (2) further comprises a second turning region (24), wherein the second turning region (24) is located between the coupling-in region (21) and the liquid crystal switch unit (3), and the light coupled in through the coupling-in region (21) is incident on the liquid crystal switch unit (3) after the pupil is expanded through the second turning region (24).

7. The display module with a liquid crystal switch according to any one of claims 1 to 3, characterized in that: The display module with a liquid crystal switch also includes a controller, which is electrically connected to the optical engine (1) and the liquid crystal switch unit (3) respectively.

8. The display module with a liquid crystal switch according to any one of claims 1 to 3, characterized in that: The coupling-in region (21) is provided with a coupling-in grating, and the coupling-out region (22) is provided with a coupling-out grating.

9. The display module with a liquid crystal switch according to any one of claims 1 to 3, characterized in that: The optical engine (1) includes LCOS, DLP or Micro-LED.

10. An AR device, characterized in that: It comprises a wearable component and a display module with a liquid crystal switch as claimed in any one of claims 1 to 9, wherein the wearable component is connected to an optical waveguide (2) of the display module with a liquid crystal switch.

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