Display module and display device

Abstract

This application discloses a display module and display device. The display module includes a first polarizer, a liquid crystal layer, a second polarizer, and a dimming layer stacked along the thickness direction of the display module. The liquid crystal layer is disposed on one side of the first polarizer, the second polarizer is disposed on the side of the liquid crystal layer opposite to the first polarizer, and the dimming layer is disposed on the side of the second polarizer opposite to the first polarizer. The dimming layer is configured to change the exit angle of light passing through it. By incorporating a dimming layer within the display module, this application can adjust and control the exit angle of light after it passes through the dimming layer, ensuring that the light exits at a preset angle. This allows the exit angle of the display module to match the principal ray angle of the optomechanical system, thereby significantly improving luminous efficiency. Simultaneously, the matching of the principal ray angle reduces light scattering into non-observation areas, effectively reducing stray light and thus mitigating ghosting.

Description

Technical Field

[0001] This application belongs to the field of display technology, specifically relating to a display module and display device. Background Technology

[0002] The folded optical path design (pancake design) of virtual reality display modules has become a mainstream optical engine design solution due to its advantages such as a large field of view, high resolution, and thinness. However, the folded optical path of virtual reality display modules has a low actual light utilization rate during the folding process; and under a large field of view, from the center of the panel to the edge of the panel, the closer to the edge of the display module, the more the light deviates from the vertical direction, resulting in severe ghosting and further reducing the light efficiency. Summary of the Invention

[0003] Purpose of the invention: This application provides a display module that aims to solve the problem of low light efficiency utilization in existing virtual reality display modules when the optical path is folded to form a large field of view; another purpose of this application is to provide a display device.

[0004] Technical solution: A display module according to an embodiment of this application includes: stacked along the thickness direction of the display module:

[0005] First polarizer;

[0006] A liquid crystal layer is disposed on one side of the first polarizer;

[0007] The second polarizer is disposed on the side of the liquid crystal layer opposite to the first polarizer;

[0008] A dimming layer is disposed on the side of the second polarizer or the first polarizer away from the liquid crystal layer;

[0009] The dimming layer is configured to impart an additional phase to the light rays incident into it in order to change the light emission angle.

[0010] In some embodiments, the dimming layer includes a third polarizer and a dimming film; the dimming film is configured to impart an additional phase to light rays incident on the dimming film to change the exit angle of the light rays;

[0011] Wherein, the third polarizer is disposed on the side of the first polarizer opposite to the liquid crystal layer, and the dimming film is disposed on the side of the third polarizer opposite to the first polarizer; or,

[0012] The third polarizer is disposed on the side of the second polarizer away from the liquid crystal layer, and the dimming film is disposed on the side of the third polarizer away from the second polarizer.

[0013] In some embodiments, the dimming film includes a plurality of liquid crystal molecules extending from the center of the display module to the edge of the display module, with the emitted light from the liquid crystal molecules tilted in a direction away from the main light ray of the display module.

[0014] In some embodiments, the third polarizer is disposed on the side of the second polarizer away from the liquid crystal layer, and the display module further includes:

[0015] A fourth polarizer is disposed on the side of the first polarizer that is away from the liquid crystal layer;

[0016] A backlight layer is disposed on the side of the dimming film opposite to the third polarizer.

[0017] In some embodiments, a fifth polarizer is further included, which is disposed on the side of the second polarizer away from the liquid crystal layer, and the fifth polarizer is located between the second polarizer and the third polarizer.

[0018] In some embodiments, the third polarizer is disposed on the side of the first polarizer away from the liquid crystal layer, and the display module further includes a backlight layer disposed on the side of the second polarizer away from the liquid crystal layer.

[0019] In some embodiments, a fifth polarizer is further included, which is disposed on the side of the second polarizer away from the liquid crystal layer, and the fifth polarizer is located between the second polarizer and the backlight layer.

[0020] In some embodiments, a reflective layer is further included, the reflective layer being disposed on the side of the backlight layer away from the fifth polarizer.

[0021] In some embodiments, the fifth polarizer is a reflective polarizer.

[0022] Accordingly, the display device described in the embodiments of this application includes the display module as described in any of the above embodiments.

[0023] Beneficial Effects: Compared with the prior art, a display module according to an embodiment of this application includes a first polarizer, a liquid crystal layer, a second polarizer, and a dimming layer stacked along the thickness direction of the display module; the liquid crystal layer is disposed on one side of the first polarizer, the second polarizer is disposed on the side of the liquid crystal layer opposite to the first polarizer, and the dimming layer is disposed on the side of the second polarizer opposite to the first polarizer; wherein, the dimming layer is configured to change the emission angle of light passing through the dimming layer. By setting a dimming layer in the display module, this application can adjust and control the emission angle of light after it passes through the dimming layer, so that the light is emitted at a preset angle, thereby achieving the matching of the emission angle of the display module with the principal ray angle of the optomechanical system, thus greatly improving the light efficiency; at the same time, since the principal ray angle is matched, the light scattering into the non-observation area is reduced, effectively reducing stray light and thus weakening ghosting.

[0024] Compared with the prior art, a display device according to an embodiment of this application includes a display module as described in any of the above embodiments. It is understood that the display device includes all the technical features and effects of the display module, which will not be repeated here. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of the overall structure of a display module according to an embodiment of this application;

[0027] Figure 2 This is a schematic diagram of the overall structure of a display module according to a second embodiment of this application;

[0028] Figure 3 This is a schematic diagram of the overall structure of a display module according to one of the three embodiments of this application;

[0029] Figure 4 This is a schematic diagram of the overall structure of a display module according to one of the four embodiments of this application;

[0030] Figure 5 This is a schematic diagram illustrating the principle of beam steering using a dimming film in a display module according to an embodiment of this application.

[0031] Figure 6 This is a schematic diagram of the liquid crystal molecule arrangement of the dimming film based on the PB phase according to an embodiment of this application;

[0032] Figure 7This is a simulation diagram of the modulation of incident light by a dimming film based on the PB phase of a display module according to an embodiment of this application;

[0033] Figure 8 This is a schematic diagram of the structure of a display device according to an embodiment of this application.

[0034] Figure label:

[0035] 100. Display module; 1. First polarizer; 2. Liquid crystal layer; 3. Second polarizer; 4. Dimming layer; 41. Third polarizer; 42. Dimming film; 421. Liquid crystal molecule; 5. Fourth polarizer; 6. Backlight layer; 7. Fifth polarizer; 8. Reflective layer; 200. Main body of the device; 300. Driving module; X, Thickness direction. Detailed Implementation

[0036] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0037] In the description of this application, it should be understood that the terms "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more features. In the description of this application, "multiple" means two or more, and "at least one" can mean one, two, or more, unless otherwise explicitly specified. In the description of this application, "perpendicular" means completely perpendicular to 90° or almost completely perpendicular, for example, the range of included angles from 80° to 100° is considered perpendicular. Similarly, "parallel" means completely parallel or almost completely parallel, for example, the range of completely parallel angles from 10° is considered parallel.

[0038] The applicant notes that with the popularization of the metaverse concept and the increasing demand for interactive experiences from display devices, virtual / augmented reality display technology has received increasingly widespread attention and research. Virtual reality (VR) technology can enhance the user's interactive experience with displayed information and is increasingly favored by consumers. Among them, the pancake optical path has become the mainstream optical engine design solution due to its advantages such as a large field of view (FOV), high resolution, and the ability to make VR devices thinner and lighter. However, this technology currently faces the following difficulties or shortcomings:

[0039] 1. From a design perspective, the light effect of the Pancake cannot be 100% utilized during the folding process; in reality, less than 25% of the light effect can be utilized.

[0040] 2. Different areas of the VR optical engine module use different angles for the main light rays used for imaging. The main light ray emitted from the center of the display is perpendicular to the panel surface, while the closer to the edge of the display, the more the main light ray deviates from the vertical direction under the corresponding large field of view. This will cause severe ghosting and further reduce the light effect.

[0041] 3. Since VR displays require close-range viewing, in order to ensure that the image quality is not affected, the resolution of VR displays usually needs to be higher than 1000ppi, which is a significant challenge for current panel manufacturing capabilities.

[0042] 4. Improving the brightness of VR displays by optimizing backlight design is quite difficult. For edge-lit backlights, placing too many LEDs will increase the size of the VR optical system, which contradicts the current research trend of making VR optical engines thinner and lighter. At the same time, the light guide plate inevitably causes significant light loss. Therefore, it is difficult for edge-lit backlights to achieve high brightness. Direct-lit backlight systems also cannot achieve high brightness due to their complex film structure.

[0043] In view of this, embodiments of this application provide a display module aimed at solving at least one of the above problems.

[0044] like Figures 1-4 As shown, a display module according to an embodiment of this application includes a first polarizer 1, a liquid crystal layer 2, a second polarizer 3, and a dimming layer 4 stacked along the thickness direction X of the display module 100; the liquid crystal layer 2 is disposed on one side of the first polarizer 1, the second polarizer 3 is disposed on the side of the liquid crystal layer 2 opposite to the first polarizer 1, and the dimming layer 4 is disposed on the side of the second polarizer 3 or the first polarizer 1 opposite to the liquid crystal layer 2; wherein, the dimming layer 4 is configured to impart an additional phase to the light rays incident on the dimming layer 4 to change the light emission angle.

[0045] In this embodiment, by providing a dimming layer 4 in the display module 100, an additional phase can be assigned to the light when it passes through the dimming layer 4 to change the light emission angle, so that the light is emitted at a preset angle, thereby enabling the light emission angle of the display module 100 to match the main light angle of the optical engine system, and thus greatly improving the light efficiency.

[0046] This application adjusts the light emission angle by adding a phase to the light, which is a physical optical adjustment that does not affect the thickness of the display module 100, thereby avoiding increasing the weight of the VR device.

[0047] Specifically, in this embodiment of the application, the display module 100, through the setting of the dimming layer 4, can control the light emission angle of each point on the display module 100 according to the light emission angle of the master ray of the adaptive light at different positions of the VR optical engine, thereby achieving the matching of the light emission angle of the display module 100 with the master ray angle designed for the VR optical system. It should be noted that the PancakeVR optical engine has a great demand for high collimation of the light source to match the object-side light emission angle with the master ray angle of its optical system. This not only reduces the light scattered into the non-observation area and maximizes energy utilization efficiency while reducing ghosting, but also improves on-axis brightness and optimizes image quality.

[0048] Of course, since VR displays require close-range viewing, a high resolution is usually required for the display module 100. Therefore, in specific embodiments, liquid crystal displays are often used for display. Thus, the display module 100 of this application embodiment includes a liquid crystal layer 2, and a first polarizer 1 and a second polarizer 3 are respectively disposed on both sides of the liquid crystal layer 2 along the thickness direction X of the display module 100. Specifically, in specific embodiments, the first polarizer 1 and the second polarizer 3 can be an upper polarizer and a lower polarizer, used to polarize and filter the light entering the liquid crystal layer 2 and emanating from the liquid crystal layer 2, thereby reducing stray light interference.

[0049] It should also be noted that in this embodiment, the first polarizer 1 can be an upper polarizer, and the second polarizer 3 can be a lower polarizer. Therefore, in this embodiment, the dimming layer 4 is located on the side of the second polarizer 3 away from the liquid crystal layer 2. In this case, the dimming layer 4 can be located on the side of the lower polarizer away from the liquid crystal layer 2. In this case, the dimming layer 4 is located on the light-incident side of the liquid crystal layer 2, and is used to first deflect the light emitted from the backlight at a preset angle, and then pass through the polarizer and the liquid crystal layer 2 to control the light emission angle. Of course, in another embodiment of this application, the dimming layer 4 is located on the side of the first polarizer 1 away from the liquid crystal layer 2. In this case, the first polarizer 1 can be an upper polarizer, and correspondingly, the dimming layer 4 is located on the light-emitting side of the liquid crystal layer 2, and performs a final deflection on the light emitted from the liquid crystal layer 2 to control the angle and position of the light at the final emission.

[0050] In addition, it should be noted that the display module 100 also includes an array substrate and a color filter substrate (not shown in the figure). The color filter substrate can be disposed on the side of the liquid crystal layer 2 away from the array substrate. The color filter substrate can also be disposed in a COA (Color Filter on Array) configuration (specifically, the method of arranging the color filter material on the pixel electrode through specific process steps during the manufacturing of the color filter substrate). The specific placement position can be adjusted as needed, and will not be elaborated here.

[0051] Furthermore, in some embodiments, the dimming layer 4 includes a third polarizer 41 and a dimming film 42; the dimming film 42 is configured to impart an additional phase to the light incident on the dimming film 42 to change the light emission angle; wherein, the third polarizer 41 is disposed on the side of the first polarizer 1 opposite to the liquid crystal layer 2, and the dimming film 42 is disposed on the side of the third polarizer 41 opposite to the first polarizer 1; or, the third polarizer 41 is disposed on the side of the second polarizer 3 opposite to the liquid crystal layer 2, and the dimming film 42 is disposed on the side of the third polarizer 41 opposite to the second polarizer 3.

[0052] In this embodiment, the light emission angle is adjusted by setting a dimming film 42. It should be noted that the dimming film 42 in this embodiment needs to meet the half-wave condition to achieve the adjustment of the light rotation direction. Therefore, the dimming film 42 in this embodiment mainly adjusts circularly polarized light, and the light emitted from the dimming film 42 is still circularly polarized light, but the incident light and the emitted light rotate in opposite directions. The liquid crystal layer 2, the first polarizer 1, and the second polarizer 3 all transmit linearly polarized light (that is, the liquid crystal layer 2, the upper polarizer, and the lower polarizer all transmit linearly polarized light), and the second polarizer 3 and the first polarizer 1 respectively perform polarization filtering on the light. Therefore, a third polarizer 41 is set between the dimming film 42 and the first polarizer 1 or the second polarizer 3, and the third polarizer 41 can be a quarter-wave plate. Correspondingly, when the dimming film 42 is located on the side of the third polarizer 41 away from the second polarizer 3, the dimming film 42 is located on the light-incident side of the liquid crystal layer 2. The circularly polarized light after the dimming film 42 adjusts the emission angle needs to be polarized by the third polarizer 41 to convert the circularly polarized light into linearly polarized light before entering the liquid crystal layer 2 for display. When the dimming film 42 is located on the side of the third polarizer 41 away from the first polarizer 1, the dimming film 42 is located on the light-emitting side of the liquid crystal layer 2. The linearly polarized light emitted from the liquid crystal layer 2 enters the third polarizer 41 (quarter-wave plate) after passing through the upper polarizer. The third polarizer 41 converts the linearly polarized light into circularly polarized light that can be adjusted by the dimming film 42. The dimming film 42 adjusts the emission angle of the circularly polarized light to adapt to the VR optical engine.

[0053] In some embodiments, the dimming film 42 includes a plurality of liquid crystal molecules 421 extending from the center of the display module 100 to the edge of the display module 100, with the emitted light from the liquid crystal molecules 421 tilted in a direction away from the main light ray from the center of the display module 100.

[0054] It should be noted that the angle of light used for imaging in different areas of the VR optical engine is different. Specifically, the main light emitted from the center of the display module 100 is perpendicular to the panel surface. The closer to the edge of the display module 100, the more the main light under the large field of view will deviate from the vertical direction. Therefore, in this embodiment, by controlling the orientation of the liquid crystal molecules 421 of the dimming film 42, the main light emitted by the liquid crystal molecules 421 gradually tilts away from the main light at the center of the display module 100 from the center to the edge of the display module 100. The further away from the center of the display module 100, the greater the deflection angle of the corresponding liquid crystal molecules 421. That is, the angle of the main light emitted by the liquid crystal molecules 421 relative to the main light at the center of the display module 100 is greater.

[0055] Specifically, the dimming film 42 in this embodiment can be an LC PB HOE dimming film 42 with beam steering capability and polarization response, manufactured using processes such as holographic exposure and laser direct writing. Here, LC represents liquid crystal molecules 421, PB represents the Pancharagh-Berry (PB) phase principle, and HOE represents a holographic optical element. That is, the dimming film 42 in this embodiment is a holographic optical thin film composed of multiple liquid crystal molecules 421 based on the PB phase principle.

[0056] It is understood that the dimming film 42 in this embodiment of the application has multiple liquid crystal molecules 421 distributed within it for modulating the light transmitted through it. Based on the PB phase principle, during the production of the dimming film 42, depending on the different principal ray angles of the VR optical engine design, to match the light emission angle of the display module 100 with the VR optical engine, liquid crystal dimming films 42 with different phase distributions can be easily designed to meet the optical engine requirements of different designs. Therefore, the dimming film 42 of the display module 100 in this embodiment of the application can be flexibly customized according to the VR optical engine of different embodiments.

[0057] It should also be noted that, based on the PB phase principle, this application sets the deflection angle of the liquid crystal molecules 421 in the dimming film 42 when the principal ray angle of the VR optical engine is known. The liquid crystal molecules 421 add an additional phase to the incident light according to their specific deflection angle, thereby changing the exit angle of the emitted light and achieving different exit angles. The dimming film 42 includes multiple liquid crystal molecules 421, each of which can be adjusted and designed according to the exit angle requirements at a specific position, thereby meeting the exit angle requirements and improving luminous efficiency.

[0058] This application achieves physical dimming by adding an additional phase to the incident light through the dimming film 42. Compared with dimming using geometric structures such as lenses, the deflection angle of the liquid crystal molecules 421 can be arbitrarily controlled, making the light control effect easier to control and implement, with higher design freedom and higher transmittance. At the same time, the dimming film 42 performs physical optical dimming through the additional phase, resulting in small wavefront aberrations, which can effectively improve the display quality.

[0059] Furthermore, this application utilizes the principle of beam steering achieved by the dimming film 42 as follows: Figure 5 As shown in the figure, after a vertically incident light beam passes through the dimming film 42, the polarization of the liquid crystal molecules 421 at point B imparts an additional phase dφ to the light, making BC an equiphase surface. This is equivalent to the dimming film 42 at point B causing the light to travel the optical path from point A to point C. Based on trigonometric relationships, the phase that the dimming film 42 should impart to the incident light at each position can be obtained according to the different radii r and deflection angles θ of each point on the dimming film 42. The specific calculation formula is as follows:

[0060]

[0061] The principle of assigning phase to light rays using the PB phase principle is as follows: The Jones matrix of a planar optical device with a rotating surface polarizing element (microstructure, liquid crystal molecule) can be expressed as:

[0062]

[0063] Where t represents transmission, and x and y represent the polarization directions of light, t xx This represents the relationship between the incident polarization amount in the x-direction and the transmitted x-direction polarization component, t. yy This represents the relationship between the incident polarization component in the y-direction and the polarization component in the y-direction after transmission.

[0064] Where R is the rotation matrix:

[0065]

[0066] When a right-handed beam of light is incident perpendicularly on this planar optical element, according to the principle of the Jones matrix, the outgoing light can be represented as:

[0067]

[0068] It can be seen that when t xx With t yy When there is a π phase difference, all the right-handed light in the outgoing light disappears, leaving only the left-handed light. The polarization conversion rate is 100%, and the left-handed light has a phase increase of 2θ compared to the incident light. Therefore, the desired phase can be obtained simply by rotating the liquid crystal molecules by a certain angle.

[0069] The selection of the liquid crystal molecule arrangement on the dimming film 42 is first based on the requirement of the main beam angle after the completion of the VR optical engine design, the deflection requirement of the light output angle of each point of the display module 100 is obtained, the phase distribution of the dimming film 42 is calculated, and then the arrangement of the liquid crystal molecules 421 of the dimming film 42 is obtained.

[0070] It should also be noted that the liquid crystal molecules of the dimming film 42 in this application can be made of different liquid crystal materials. Different liquid crystal materials have different refractive indices. Simultaneously, the dimming film 42 converts circularly polarized light into circularly polarized light with the opposite polarization direction. This means the dimming film needs to meet the half-wave condition. Different liquid crystal materials, based on their different refractive indices and incident wavelengths, will have different thicknesses due to the different materials. In addition to controlling the deflection angle of the liquid crystal molecules 421, parameters such as the refractive index of the liquid crystal material and the thickness of the dimming film 42 also affect the direction and intensity of the light coupling. Therefore, by screening liquid crystal materials and selecting those with suitable refractive indices, a corresponding thickness of the dimming film 42 can be achieved, thus allowing for more precise control of the direction and intensity of the light coupling.

[0071] Given the principal beam angle of the VR optical engine design, in order to meet the design requirements of matching the screen emitted light with the VR principal beam angle, the phase corresponding to each radius value of the dimming film can be calculated using equation (1) and a fitting curve can be obtained. Then, the rotation angle of the liquid crystal molecules based on the PB phase principle can be calculated through the relationship between the phase distribution and the molecular rotation angle. Subsequently, a dimming film 42 with beam steering capability and polarization response that conforms to the VR optical engine principal beam angle design curve is produced using holographic exposure, laser direct writing and other processes.

[0072] One embodiment of the arrangement of liquid crystal molecules 421 in the dimming film 42 is as follows: Figure 6 As shown, the liquid crystal molecules 421 on the dimming film 42 are arranged in multiple concentric circles, and the principal ray angles of the emitted light corresponding to the liquid crystal molecules 421 on each circle are the same. To verify the modulation effect of the PB phase on the incident light, a simulation was performed using COMSOL, as shown below. Figure 7As shown, when the refractive index distribution of the given dimming film 42 structure surface is (f-sqrt(f^2+x^2+y^2))*π / λ, it can be seen that it can deflect parallel incident light. Therefore, dimming films 42 with different phase distributions can be designed according to the specific design of the principal ray angle of the optical engine to meet the needs of VR optical engine use.

[0073] like Figure 1 As shown, in one embodiment, the display module 100 includes a first polarizer 1, a liquid crystal layer 2, a second polarizer 3, and a dimming layer 4 stacked along the thickness direction X of the display module 100; the liquid crystal layer 2 is disposed on one side of the first polarizer 1, the second polarizer 3 is disposed on the side of the liquid crystal layer 2 away from the first polarizer 1, and the dimming layer 4 is disposed on the side of the second polarizer 3 away from the liquid crystal layer 2; the dimming layer 4 includes a third polarizer 41 and a dimming film 42, the third polarizer 41 is disposed on the side of the second polarizer 3 away from the liquid crystal layer 2, and the dimming film 42 is disposed on the side of the third polarizer 41 away from the second polarizer 3; the display module 100 also includes a fourth polarizer 5 and a backlight layer 6, the fourth polarizer 5 is disposed on the side of the first polarizer 1 away from the liquid crystal layer 2, and the backlight layer 6 is disposed on the side of the dimming film 42 away from the third polarizer 41.

[0074] In this embodiment, the dimming layer 4 is disposed on the light-emitting side of the backlight layer 6. At this time, the light first passes through the dimming layer 4, and then is emitted through the polarizer and the liquid crystal layer 2.

[0075] It should be noted that in this embodiment, the backlight layer 6 emits circularly polarized light that is not unidirectional. The PB phase has polarization selectivity for the incident light, and can only redirect incident light of one direction of rotation, such as the left-hand circularly polarized light (L light) shown in the figure. That is, the dimming film 42 adjusts the direction of the left-hand circularly polarized light emitted by the backlight layer 6. Then, the redirected left-hand circularly polarized light passes through the third polarizer 41 (quarter-wave plate) and is converted into longitudinal linearly polarized light (P light). The longitudinal linearly polarized light is emitted at an exit angle that matches the principal ray angle of the VR optical engine, and passes through the second polarizer 3, the liquid crystal layer 2, and the first polarizer 1 in sequence, and then enters the fourth polarizer 5 for further polarization. It should be noted that the fourth polarizer 5 can be a quarter-wave plate. The longitudinal linearly polarized light reaches the fourth polarizer 5 after being polarized and filtered by the first polarizer 1, and is converted into left-hand circularly polarized light again before being emitted from the display module 100. At the same time, for the right-hand circularly polarized light that is not deflected (such as...), Figure 1 The intermediate R light is converted into transversely polarized light (such as light from the third polarizer 41) by the third polarizer 41. Figure 1The light emitted from the backlight (S-beam) then reaches the second polarizer 3 and is absorbed by it. Therefore, in this embodiment, the non-single circularly polarized light emitted from the backlight passes through the dimming film 42 to adjust the angle of the left-hand circularly polarized light before being emitted and entering the third polarizer 41 to be converted into linearly polarized light. The longitudinally polarized light then passes through the second polarizer 3, the liquid crystal layer 2, and the first polarizer 1 in sequence before entering the fourth polarizer 5. The fourth polarizer 5 converts the light backlight into circularly polarized light again, which is then used by the VR optical engine.

[0076] In this embodiment, by setting a dimming layer 4 on the light-emitting side of the backlight layer 6 and setting a fourth polarizer 5 on the side of the dimming film 42 away from the backlight layer 6, the angle of light can be directly adjusted on the light-incident side of the liquid crystal layer 2. The subsequent multiple polarizers and the liquid crystal layer 2 will only further polarize or transmit the light, but will not change the light emission angle. Therefore, the preset angle of light emission can be achieved, which meets the usage requirements of VR optical engines.

[0077] like Figure 2 As shown, the second embodiment of this application, based on the first embodiment, further includes a fifth polarizer 7. The fifth polarizer 7 is disposed on the side of the second polarizer 3 facing away from the liquid crystal layer 2, and is located between the second polarizer 3 and the third polarizer 41. Furthermore, the fifth polarizer 7 is a reflective polarizer.

[0078] Specifically, such as Figure 2 As shown in this embodiment, the fifth polarizer 7 is disposed between the third polarizer 41 and the second polarizer 3, and is attached to the second polarizer 3. At this time, the longitudinally linearly polarized light, after being polarized by the third polarizer 41, smoothly passes through the fifth polarizer 7 and enters the second polarizer 3, eventually exiting to the outside of the display module 100. However, the transversely linearly polarized light, after being converted by the third polarizer 41, is reflected back to the third polarizer 41 by the fifth polarizer 7, and is again converted into right-hand circularly polarized light by the third polarizer 41. It then passes through the dimming film 42 and returns to the backlight layer 6, where it can be reused, effectively reducing energy consumption.

[0079] like Figure 3 As shown, the display module 100 of the three embodiments of this application includes a first polarizer 1, a liquid crystal layer 2, a second polarizer 3, and a dimming layer 4 stacked along the thickness direction X of the display module 100; the liquid crystal layer 2 is disposed on one side of the first polarizer 1, the second polarizer 3 is disposed on the side of the liquid crystal layer 2 away from the first polarizer 1, and the dimming layer 4 is disposed on the side of the first polarizer 1 away from the liquid crystal layer 2; the dimming layer 4 includes a third polarizer 41 and a dimming film 42, the third polarizer 41 is disposed on the side of the first polarizer 1 away from the liquid crystal layer 2, and the dimming film 42 is disposed on the side of the third polarizer 41 away from the first polarizer 1; the display module 100 also includes a backlight layer 6, the backlight layer 6 is disposed on the side of the second polarizer 3 away from the liquid crystal layer 2.

[0080] It should be noted that in this embodiment, the dimming layer 4 is disposed on the light-emitting surface of the display module 100. At this time, the dimming layer 4 uses the dimming film 42 to make a final angle adjustment of the light emitted by the display module 100, so that the light emission angle is precisely controlled, and the accuracy of the light emission angle control is further improved.

[0081] Specifically, such as Figure 3 As shown, in this embodiment, the light emitted by the backlight layer 6 is non-single polarized linear light. The non-single polarized linear light directly enters the second polarizer 3 for stray light filtering. The longitudinal linearly polarized light (P light in the figure) passes smoothly through the second polarizer 3, while the transverse linearly polarized light (S light in the figure) is absorbed by the second polarizer 3. Then, the longitudinal linearly polarized light continues to pass through the liquid crystal layer 2 to reach the first polarizer 1 for further polarization filtering. After passing through the first polarizer 1, the longitudinal linearly polarized light enters the third polarizer 41 for polarization and is converted into right-hand circularly polarized light (R light in the figure). The right-hand circularly polarized light can be adjusted by the dimming film 42 to deflect the light out at a predetermined angle, thus achieving effective control of the angle of the light emitted by the display module 100.

[0082] Furthermore, such as Figure 4 As shown, the display module 100 of the four embodiments of this application, based on the three embodiments, further includes a fifth polarizer 7. The fifth polarizer 7 is disposed on the side of the second polarizer 3 facing away from the liquid crystal layer 2, and is located between the second polarizer 3 and the backlight layer 6. Furthermore, the fifth polarizer 7 is a reflective polarizer.

[0083] In this embodiment, the fifth polarizer 7 is disposed between the backlight layer 6 and the second polarizer 3, and is attached to the second polarizer 3. At this time, the non-single-polarized linearly polarized light emitted from the backlight layer 6 directly enters the fifth polarizer 7. The longitudinally polarized light is transmitted through the fifth polarizer 7, while the transversely polarized light is directly reflected back to the backlight layer 6 by the fifth polarizer 7, facilitating the reuse of the backlight layer 6 and effectively reducing energy consumption. After being transmitted through the fifth polarizer 7, the longitudinally polarized light first passes through the second polarizer 3 for polarization filtering, further filtering out excess stray light. Then, the longitudinally polarized light after passing through the second polarizer 3 passes through the liquid crystal layer 2 and enters the first polarizer 1 for further polarization filtering, and then passes through the third polarizer 41 to be converted into left-hand circularly polarized light (e.g., ...). Figure 4 As shown in the figure, the light is finally converted into right-hand circularly polarized light by the dimming film 42 and emitted outward for use by the VR optical engine.

[0084] In some embodiments, a reflective layer 8 is also included, which is disposed on the side of the backlight layer 6 away from the fifth polarizer 7.

[0085] In this embodiment, a reflective layer 8 is provided on the side of the backlight layer 6 away from the fifth polarizer 7. At this time, the light emitted by the backlight layer 6 can be emitted towards the side of the backlight layer 6 away from the reflective layer 8. At the same time, the light reflected back to the backlight layer 6 by the fifth polarizer 7 can be further reflected as the emitted light of the backlight layer 6 and reused as unpolarized light, thereby effectively improving the light efficiency.

[0086] Accordingly, a display device according to an embodiment of this application includes a display module 100 as described in any of the above embodiments; the display device further includes a device body 200 and a driving module 300, the driving module 300 and the display module 100 being disposed on the device body 200, and the driving module 300 being connected to the display module 100 for driving the display module 100 to work. It is understood that this display device may possess all the technical features and effects of the display module 100, which will not be elaborated upon here.

[0087] The display device in this application embodiment can be a near-eye display device such as VR glasses.

[0088] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0089] The above provides a detailed description of a display module and display device provided in the embodiments of this application, and uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the technical solutions and core ideas of this application. Those skilled in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A display module, characterized in that, include: Stacked along the thickness direction of the display module: First polarizer; A liquid crystal layer is disposed on one side of the first polarizer; The second polarizer is disposed on the side of the liquid crystal layer opposite to the first polarizer; A dimming layer is disposed on the side of the second polarizer or the first polarizer away from the liquid crystal layer; The dimming layer is configured to impart an additional phase to the light rays incident into it, thereby changing the exit angle of the light rays; The dimming layer includes a dimming film, which includes a holographic optical film and a plurality of liquid crystal molecules. From the center of the display module to the edge of the display module, the emitted light from the liquid crystal molecules is tilted away from the main ray of the display module. The further away from the center of the display module, the larger the deflection angle of the corresponding liquid crystal molecules. The dimming film is configured to impart an additional phase to the light rays incident on the dimming film to change the emission angle of the light rays so that the emission angle of the display module matches the main ray angle of the optomechanical system. The display module further includes a fifth polarizer, which is disposed on the side of the second polarizer away from the liquid crystal layer, and the fifth polarizer is a reflective polarizer.

2. The display module according to claim 1, characterized in that, The dimming layer includes a third polarizer disposed on the side of the first polarizer facing away from the liquid crystal layer, and the dimming film disposed on the side of the third polarizer facing away from the first polarizer; or, The third polarizer is disposed on the side of the second polarizer away from the liquid crystal layer, and the dimming film is disposed on the side of the third polarizer away from the second polarizer.

3. The display module according to claim 2, characterized in that, When the third polarizer is disposed on the side of the second polarizer away from the liquid crystal layer, the display module further includes: A fourth polarizer is disposed on the side of the first polarizer that is away from the liquid crystal layer; A backlight layer is disposed on the side of the dimming film opposite to the third polarizer.

4. The display module according to claim 3, characterized in that, The fifth polarizer is located between the second polarizer and the third polarizer.

5. The display module according to claim 2, characterized in that, When the third polarizer is disposed on the side of the first polarizer away from the liquid crystal layer, the display module further includes a backlight layer, which is disposed on the side of the second polarizer away from the liquid crystal layer.

6. The display module according to claim 5, characterized in that, The fifth polarizer is located between the second polarizer and the backlight layer.

7. The display module according to any one of claims 4 or 6, characterized in that, It also includes a reflective layer disposed on the side of the backlight layer away from the fifth polarizer.

8. A display device, characterized in that, Includes the display module as described in any one of claims 1-7.

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