Display screen and VR display device

Abstract

The application discloses a display screen and a VR display device. The display screen comprises a display panel, a polarization conversion layer and a first geometric phase element. Each sub-pixel of the display panel emits incident light during display, and an occlusion area is formed between two adjacent sub-pixels. The polarization conversion layer is arranged on the light-emitting side of the display panel, and the first geometric phase element is arranged on the side of the polarization conversion layer away from the display panel. During display of two adjacent frames of pictures, the polarization conversion layer corresponds to a first conversion mode and a second conversion mode, respectively. In the first conversion mode, the incident light is converted into first emitted light which is emitted vertically and covers the light-emitting area. In the second conversion mode, the incident light is converted into second emitted light which is emitted vertically. The polarization direction of the second emitted light is the same as that of the first emitted light, and the emission path is parallel. The second emitted light covers the occlusion area on the adjacent side.

Description

Technical Field

[0001] This application relates to the field of display technology, specifically to a display screen and a VR display device. Background Technology

[0002] With the increasing demand for interactive information display experiences and the popularization of XR (Extended Reality) technology, the market prospects for VR (Virtual Reality) display technology are becoming increasingly broad. SDE (Screen Door Effect) is one of the important indicators for evaluating the image quality of VR devices. SDE occurs because VR device screens have insufficient resolution and low aperture ratios, and non-illuminated periodic structures such as BM (black matrix) are larger than the minimum resolution of the human eye, thus causing users to perceive black gaps between subpixels. Existing methods to solve the screen door effect include: one is to equip VR devices with ultra-high subpixel density displays or reduce the FOV (Field of View) of VR devices, but reducing the FOV affects the immersion of VR devices; the other is to use mechanical image shifters to slightly move the image, but this will increase the spatial volume of the VR device and cause users to feel vibrations. Summary of the Invention

[0003] This application provides a display screen and a VR display device, which can not only improve the resolution of the display screen, optimize the imaging quality, and alleviate the screen-door effect, but also make the display screen thinner and lighter.

[0004] In a first aspect, embodiments of this application provide a display screen, including:

[0005] The display panel includes a plurality of sub-pixels arranged in an array, each sub-pixel forming a light-emitting area and a light-shielding area forming between adjacent sub-pixels;

[0006] A polarization conversion layer is disposed on the light-emitting side of the display panel. When two adjacent frames are displayed, the polarization conversion layer respectively has a first conversion mode and a second conversion mode; and...

[0007] A first geometric phase element is disposed on the side of the polarization conversion layer away from the display panel;

[0008] In the first conversion mode, the incident light emitted by the sub-pixel passes through the polarization conversion layer and forms a first circularly polarized light. The first circularly polarized light is perpendicularly transmitted through the first geometric phase element and forms a first outgoing light, which covers the light-emitting area.

[0009] In the second conversion mode, the incident light emitted by the sub-pixel passes through the polarization conversion layer and forms a second circularly polarized light. The second circularly polarized light is converted by the first geometric phase element and forms a second outgoing light. The polarization direction of the second outgoing light is the same as that of the first outgoing light and the outgoing path is parallel. The second outgoing light covers the light-shielding area on the adjacent side.

[0010] In one embodiment, the incident light is configured as linearly polarized light;

[0011] The polarization conversion layer includes:

[0012] The first liquid crystal waveplate is located on the light-emitting side of the display panel. The first liquid crystal waveplate is used to change the polarization state of light. When two adjacent frames are displayed, the liquid crystal molecules in the first liquid crystal waveplate have a first deflection angle and a second deflection angle.

[0013] A second geometric phase element is disposed on the side of the first liquid crystal waveplate away from the display panel. The second geometric phase element and the first geometric phase element have the same deflection angle for the light emission path but different deflection directions, and both respond to light with the same polarization direction; and,

[0014] The second liquid crystal waveplate is disposed on the side of the second geometric phase element away from the first liquid crystal waveplate. The second liquid crystal waveplate is used to change the polarization direction of light. When two adjacent frames are displayed, the liquid crystal molecules in the second liquid crystal waveplate have a third deflection angle and a fourth deflection angle.

[0015] In the first conversion mode, the liquid crystal molecules in the first liquid crystal waveplate are at the first deflection angle, the liquid crystal molecules in the second liquid crystal waveplate are at the third deflection angle, and the incident light is converted into the first circularly polarized light and emitted perpendicularly.

[0016] In the second conversion mode, the liquid crystal molecules in the first liquid crystal waveplate are at the second deflection angle, and the liquid crystal molecules in the second liquid crystal waveplate are at the fourth deflection angle, and the incident light is converted into the second circularly polarized light and refracted out.

[0017] In one embodiment, the first liquid crystal waveplate includes two first substrates, two first electrode layers and a first liquid crystal layer. The two first electrode layers are respectively disposed on two opposite surfaces of the two first substrates, and the first liquid crystal layer is disposed between the two first electrode layers. A first preset voltage is applied to the first liquid crystal layer.

[0018] The second liquid crystal waveplate includes two second substrates, two second electrode layers, and a second liquid crystal layer. The two second electrode layers are respectively disposed on two opposite surfaces of the two second substrates, and the second liquid crystal layer is placed between the two second electrode layers. A second preset voltage is applied to the second liquid crystal layer.

[0019] In one embodiment, the liquid crystal molecules of the first geometric phase element and the second geometric phase element have different arrangement directions but the same tilt angle.

[0020] In one embodiment, the incident light is configured as circularly polarized light;

[0021] The polarization conversion layer includes a third geometric phase element, which is disposed between the first geometric phase element and the display panel. The third geometric phase element and the first geometric phase element have the same deflection angle for the light emission path but different deflection directions, and respond to light with different polarization directions respectively.

[0022] In the first conversion mode, the third geometric phase element is in a transmission state, and the incident light is perpendicularly transmitted through the third geometric phase element to form the first circularly polarized light emitted.

[0023] In the second conversion mode, the third geometric phase element is in a deflection state, and the incident light is converted by the third geometric phase element to form the second circularly polarized light emitted.

[0024] In one embodiment, the third geometric phase element includes two third substrates disposed opposite to each other, and a third liquid crystal layer disposed between the two third substrates, wherein at least one of the third substrates is provided with a third electrode layer;

[0025] In the first conversion mode, the electrode layer is energized, and the liquid crystal molecules of the third liquid crystal layer are deflected to form a field-nematic phase, so that the incident light is perpendicularly transmitted through the third liquid crystal layer;

[0026] In the second conversion mode, the electrode layer is de-energized, and the liquid crystal molecules of the third liquid crystal layer are in an initial state to convert the outgoing path and polarization direction of the incident light.

[0027] In one embodiment, the first geometric phase element is configured as a Bragg grating structure.

[0028] In one embodiment, the grating thickness parameter of the first geometric phase element is set to Q, where, λ is the wavelength of light in the medium, d is the thickness of the first geometric phase element, Λ is the grating constant, and n is the average refractive index;

[0029] When Q≥1, the first geometric phase element is set as a Bragg grating structure.

[0030] In one embodiment, the display panel includes:

[0031] Backlight module; and,

[0032] The display module is disposed on the light-emitting side of the backlight module. The display module includes an array substrate and a color filter substrate disposed opposite to each other, and a liquid crystal layer disposed between the array substrate and the color filter substrate. The color filter substrate includes a substrate, a black matrix, and a color resist layer. The black matrix is ​​disposed on the side of the substrate facing the array substrate, and the color resist layer is disposed on the side of the substrate facing the array substrate. The color resist layer includes a plurality of color resist blocks arranged in an array, and the plurality of color resist blocks are distributed within the black matrix.

[0033] Each of the color resist blocks forms a light-emitting area, and the black matrix between two adjacent color resist blocks forms a light-blocking area.

[0034] Secondly, embodiments of this application also provide a VR display device, including a display screen and a frame disposed around the display screen;

[0035] The display screen is configured as described above.

[0036] Beneficial effects: In the display screen provided by this application, the incident light emitted during sub-pixel display is converted into first circularly polarized light and second circularly polarized light with different polarization directions after passing through the polarization conversion layer. The first circularly polarized light is perpendicularly transmitted through the first geometric phase element and forms a first outgoing light, which covers the light-emitting area. The second circularly polarized light is converted by the first geometric phase element and forms a second outgoing light, which covers the light-shielding area on the adjacent side. That is, the first outgoing light corresponds to the light-emitting area, and the second outgoing light corresponds to the light-shielding area. In this way, the second outgoing light converts the light-shielding area into the light-emitting area, eliminating the influence of the light-shielding area on the human eye, alleviating the screen-door effect, improving the resolution of the display screen, and optimizing the imaging quality. Moreover, the second outgoing light and the first outgoing light have the same polarization direction and parallel emission paths, that is, the same rotation direction. This optical path can be applied to the folded optical path of the current mainstream VR Pancake optical engine, thereby enabling the display screen to be applied to the current mainstream VR Pancake optical engine module and improving the competitiveness of the product. Meanwhile, since the deflection angle of the liquid crystal molecules in the first geometric phase element can impart both wavefront phase and deflection angle to the light beam, users can design geometric phase elements with different phase distributions based on the sub-pixel arrangement of the display screen, thereby improving the applicability of the product. Furthermore, because the first geometric phase element has an ultra-thin shape factor, with a thickness only the thickness of a single film, it contributes to the thinning and lightening of the display screen and the VR display device. Attached Figure Description

[0037] The technical solution and other beneficial effects of this application will become apparent from the following detailed description of specific embodiments in conjunction with the accompanying drawings.

[0038] Figure 1 A structural diagram of the display screen provided in an embodiment of this application;

[0039] Figure 2 for Figure 1 The subpixel arrangement diagram of the display screen;

[0040] Figure 3 A structural diagram of the first geometric phase element provided in an embodiment of this application;

[0041] Figure 4 for Figure 3 The light transmission path diagram of the first geometric phase element in the diagram;

[0042] Figure 5 This is a first type of film layer diagram for a display screen provided in an embodiment of this application;

[0043] Figure 6 For light to pass through Figure 5 A schematic diagram of the first type of beam deflection;

[0044] Figure 7 For light to pass through Figure 5 A schematic diagram of the second type of beam deflection;

[0045] Figure 8 This is a second film layer diagram of the display screen provided in an embodiment of this application;

[0046] Figure 9 for Figure 8 A schematic diagram of the molecular arrangement of the third geometric phase element (applied voltage);

[0047] Figure 10 for Figure 8 A schematic diagram of the molecular arrangement of the third geometric phase element (without applied voltage);

[0048] Figure 11 This is a schematic diagram of the structure of a VR display device provided in an embodiment of this application. Detailed Implementation

[0049] 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.

[0050] In the description of this application, it should be understood that the terms "above," "below," "front," "back," "left," "right," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and should not be construed as limiting this application. Furthermore, unless otherwise expressly specified and limited, "above" or "below" the second feature of the first feature merely indicates that the first feature is at a higher or lower level than the second feature, and does not indicate a direct connection relationship.

[0051] Furthermore, the terms "first" and "second" are used for descriptive purposes only, and features defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0052] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation", "connection" and "linking" should be interpreted broadly without specifically limiting the connection method. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0053] The following disclosure provides many different embodiments for implementing different structures of this application. To simplify the disclosure of this application, specific examples of components and arrangements are described below. Of course, these are merely examples and are not intended to limit the scope of this application. Furthermore, various specific examples of processes and materials are provided in this application, but those skilled in the art will recognize the application of other processes and / or the use of other materials.

[0054] This application provides a display screen and a VR display device. The VR display device can be VR glasses, VR head-mounted displays, etc., and is not limited thereto.

[0055] In a first aspect, embodiments of this application provide a display screen 100. The display screen 100 includes a display panel 1, a polarization conversion layer 2, and a first geometrical phase element 3; the display panel 1 includes a plurality of sub-pixels arranged in an array, each sub-pixel forming a light-emitting area 1a, and adjacent sub-pixels forming a light-shielding area 1b; the polarization conversion layer 2 is disposed on the light-emitting side of the display panel 1, and when two adjacent frames are displayed, the polarization conversion layer 2 respectively has a first conversion mode and a second conversion mode; the first geometrical phase element 3 is disposed on the side of the polarization conversion layer 2 away from the display panel 1; in the first conversion mode, the light emitted by the sub-pixel... Incident light A passes through the polarization conversion layer 2 and forms a first circularly polarized light B. The first circularly polarized light B is perpendicularly transmitted through the first geometric phase element 3 and forms a first outgoing light D. The first outgoing light D covers the light-emitting area 1a. In the second conversion mode, incident light A emitted by the sub-pixel passes through the polarization conversion layer 2 and forms a second circularly polarized light C. The second circularly polarized light C is converted by the first geometric phase element 3 and forms a second outgoing light E. The second outgoing light E has the same polarization direction as the first outgoing light D and its outgoing path is parallel. The second outgoing light E covers the light-shielding area 1b on the adjacent side.

[0056] Please see Figure 1 and Figure 2A polarization conversion layer 2 and a first geometric phase element 3 are added to the light-emitting side of the display panel 1. After the incident light A passes through the polarization conversion layer 2, it is converted into a first circularly polarized light B and a second circularly polarized light C with opposite polarization directions. The first circularly polarized light B is perpendicularly transmitted through the first geometric phase element 3 and forms a first emitted light D. The first emitted light D covers the light-emitting area 1a. The second circularly polarized light C is converted by the first geometric phase element 3 and forms a second emitted light E. The second emitted light E covers the light-shielding area 1b on the adjacent side. That is, the first emitted light D corresponds to the light-emitting area 1a, and the second emitted light E corresponds to the light-shielding area 1b. In this way, the second emitted light E converts the light-shielding area 1b into the light-emitting area 1a, eliminating the influence of the light-shielding area 1b on the human eye, alleviating the screen-door effect, improving the resolution of the display screen 100, and optimizing the imaging quality.

[0057] Furthermore, the second circularly polarized beam C and the first circularly polarized beam B have the same polarization direction when emitted from the first geometrical phase element 3, meaning they have the same rotation direction. This optical path is applicable to the folded optical path of the current mainstream VR Pancake optical engine, thus enabling the display screen 100 to be used in the current mainstream VR Pancake optical engine module, improving the product's competitiveness. Simultaneously, since the deflection angle of the liquid crystal molecules 31 in the first geometrical phase element 3 can impart both wavefront phase and deflection angle to the beam, users can design geometrical phase elements with different phase distributions based on the sub-pixel arrangement of the display screen 100, thereby improving the product's applicability. Moreover, because the first geometrical phase element 3 has an ultra-thin shape factor, with a thickness only the thickness of a single film, it contributes to the thinning and lightening of the display screen 100 and the VR display device.

[0058] It is known that the principle by which the first geometrical phase element 3 imparts phase to the light rays is as follows: the Jones matrix of a planar optical element rotating from a surface polarization element (e.g., a microstructure or liquid crystal molecule 31) can be expressed as... Where txx is the transmission coefficient in the x-direction when linearly polarized light is incident in the x-direction, tyy is the transmission coefficient in the y-direction when linearly polarized light is incident in the y-direction, and R(-θ) and R(θ) are rotation matrices. Multiplying the Cartesian coordinate system by the rotation matrix after rotating it counterclockwise by θ transforms the coordinate system into the rotated coordinate system. The rotation matrix R(θ) can be expressed as...

[0059] When a right-handed beam of light is incident perpendicularly on this planar optical element, please refer to... Figure 3 and Figure 4 According to the principle of the Jones matrix, the emitted light can be represented as: Where Eout is the vector of the outgoing light in the Jones matrix, and the outgoing light vector is equal to the incident light vector multiplied by the Jones matrix of the element; i is the imaginary part.

[0060] As can be seen from the above formula, when there is a π phase difference between txx and tyy, all the right-handed light in the outgoing light disappears, leaving only 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 phase of the outgoing light can be adjusted simply by adjusting the deflection angle of the liquid crystal molecules 31 in the first geometric phase element 3.

[0061] This application does not impose specific restrictions on the polarization state of the incident light A. The incident light A can be linearly polarized light or circularly polarized light.

[0062] It should be noted that this application does not impose specific limitations on the structure of the polarization conversion layer 2. The polarization conversion layer 2 includes a switchable phase liquid crystal element with beam steering capability and polarization response, or a non-switchable phase liquid crystal element controlled by timing, which is fabricated using processes such as holographic exposure, DMD (Digital Micromirror Devices), and laser direct writing.

[0063] In one embodiment, the incident light A is set as linearly polarized light; the polarization conversion layer 2 includes a first liquid crystal waveplate 21, a second geometric phase element 22, and a second liquid crystal waveplate 23. The first liquid crystal waveplate 21 is located on the light-emitting side of the display panel 1. The first liquid crystal waveplate 21 is used to change the polarization state of the light. When two adjacent frames are displayed, the liquid crystal molecules in the first liquid crystal waveplate 21 have a first deflection angle and a second deflection angle; the second geometric phase element 22 is located on the side of the first liquid crystal waveplate 21 away from the display panel 1. The second geometric phase element 22 and the first geometric phase element 23 have the same deflection angle and different deflection directions for the light emission path, and both respond to light with the same polarization direction; the second liquid crystal waveplate 23 is located on the side of the first liquid crystal waveplate 21 away from the display panel 1. Two geometric phase elements 22 are located on the side away from the first liquid crystal waveplate 21. The second liquid crystal waveplate 23 is used to change the polarization direction of light. When two adjacent frames are displayed, the liquid crystal molecules in the second liquid crystal waveplate 23 have a third deflection angle and a fourth deflection angle. In the first conversion mode, the liquid crystal molecules in the first liquid crystal waveplate 21 are at the first deflection angle, and the liquid crystal molecules in the second liquid crystal waveplate 23 are at the third deflection angle. The incident light A is converted into the first circularly polarized light B and emitted perpendicularly. In the second conversion mode, the liquid crystal molecules in the first liquid crystal waveplate 21 are at the second deflection angle, and the liquid crystal molecules in the second liquid crystal waveplate 23 are at the fourth deflection angle. The incident light A is converted into the second circularly polarized light C and refracted.

[0064] It should be noted that this application does not impose specific restrictions on the polarization direction of the first geometric phase element 3 and the second geometric phase element 22 that generate the response. It is now assumed that both the first geometric phase element 3 and the second geometric phase element 22 respond to right-handed circularly polarized light.

[0065] In this embodiment, please refer to Figure 5 In the first conversion mode, the linearly polarized light is converted into left-hand circularly polarized light by the first liquid crystal waveplate 21. The left-hand circularly polarized light can be transmitted perpendicularly through the second geometric phase element 22. At this time, the second liquid crystal waveplate 23 switches to allow the left-hand circularly polarized light to be transmitted perpendicularly, forming the first circularly polarized light B, which is then transmitted to the first geometric phase element 3. In the second conversion mode, the linearly polarized light is converted into right-hand circularly polarized light by the first liquid crystal waveplate 21. The right-hand circularly polarized light is converted into left-hand circularly polarized light by the second geometric phase element 22, and its exit path is deflected. The left-hand circularly polarized light is converted into right-hand circularly polarized light by the second liquid crystal waveplate 23, and its exit path remains unchanged, forming the second circularly polarized light C, which is then transmitted to the first geometric phase element 3. That is to say, before entering the first geometric phase element 3, the first circularly polarized light B is left-hand circularly polarized light, and the second circularly polarized light C is right-hand circularly polarized light. The first circularly polarized light B and the second circularly polarized light C are set at an angle.

[0066] Since the first geometric phase element 3 also responds to right-hand circularly polarized light, the first circularly polarized light B can be transmitted perpendicularly through the first geometric phase element 3 to form the first outgoing light D. The second circularly polarized light C is converted by the first geometric phase element 3 into left-hand circularly polarized light, and its outgoing path is deflected. Furthermore, since the second geometric phase element 22 and the first geometric phase element 3 have the same deflection angle and different deflection directions on the light outgoing path, the second circularly polarized light C can also be emitted perpendicularly from the first geometric phase element 3 to form the second outgoing light E. In other words, the first circularly polarized light B and the second circularly polarized light C emitted from the first geometric phase element 3 have the same polarization direction and parallel outgoing paths.

[0067] In one embodiment, the first liquid crystal waveplate 21 includes two first substrates, two first electrode layers, and a first liquid crystal layer. The two first electrode layers are respectively disposed on two opposite surfaces of the two first substrates, and the first liquid crystal layer is disposed between the two first electrode layers. The first liquid crystal layer is subjected to a first preset voltage. The second liquid crystal waveplate 23 includes two second substrates, two second electrode layers, and a second liquid crystal layer. The two second electrode layers are respectively disposed on two opposite surfaces of the two second substrates, and the second liquid crystal layer is disposed between the two second electrode layers. The second liquid crystal layer is subjected to a second preset voltage.

[0068] The first liquid crystal layer is placed between the two first electrode layers, and the first liquid crystal layer may be a nematic liquid crystal. By energizing the two first electrode layers to apply a voltage to the first liquid crystal layer, the liquid crystal molecules in the first liquid crystal layer can be controlled to flip, causing the o-ray and e-ray of the liquid crystal birefringence to produce different phase differences. The phase difference between the o-ray and e-ray produced by the liquid crystal birefringence is in the range of π / 2 to 2π, so that the first liquid crystal waveplate 21 can convert the linearly polarized light into circularly polarized light with different polarization directions.

[0069] Similarly, the second liquid crystal layer is placed between the two second electrode layers, and the second liquid crystal layer can be a nematic liquid crystal. By energizing the two second electrode layers to apply a voltage to the second liquid crystal layer, the liquid crystal molecules in the second liquid crystal layer can be controlled to flip, causing the o-ray and e-ray of the liquid crystal birefringence to produce different phase differences. The phase difference between the o-ray and e-ray produced by the liquid crystal layer birefringence is in the range of π / 2 to 2π, so that the second liquid crystal waveplate 23 can allow light to be transmitted perpendicularly or change the polarization direction of the light.

[0070] This application does not impose specific limitations on the first preset voltage and the second preset voltage. In one embodiment, the first preset voltage is set to 0V~10V, and the second preset voltage is set to 0V~10V, thereby enabling the first liquid crystal waveplate and the second liquid crystal waveplate to achieve dynamic switching between different types of waveplates under a relatively small voltage drive.

[0071] The user can calculate the deflection angle of the incident light A based on the arrangement of the sub-pixels, thereby adjusting the arrangement of the liquid crystal molecules 31 of the first geometric phase element 3 and the second geometric phase element 22. Taking the LCD liquid crystal display screen 100 as an example, assuming the size of a single sub-pixel is 16.8*16.8μm and the length of each color block is 8μm, then the incident light A needs to be shifted by approximately 8 micrometers. Assuming the deflection gap is 2μm, then the required deflection angle of the incident light A is arctan8 / 4, approximately 63°.

[0072] In one embodiment, the liquid crystal molecules 31 of the first geometric phase element 3 and the second geometric phase element 22 are arranged in opposite directions but tilted at the same angle; this enables the second geometric phase element 22 and the first geometric phase element 3 to have the same deflection angle for the light emission path but opposite deflection directions; the grating period of the first geometric phase element 3 and the second geometric phase element 22 is set to 275 μm, with 15 deflection molecules evenly distributed within one period. The deflection angle of the liquid crystal molecules 31 of the first geometric phase element 3 is set to x / 15*π, and the deflection angle of the liquid crystal molecules 31 of the second geometric phase element 22 is set to -x / 15*π. Please refer to [link to relevant documentation]. Figure 6 and Figure 7 When right-handed circularly polarized light is incident, observing the outgoing left-handed circularly polarized light reveals that the left-handed circularly polarized light has the same deflection angle but opposite direction.

[0073] In another embodiment, please refer to Figure 8 The incident light A is set as circularly polarized light; the polarization conversion layer 2 includes a third geometric phase element 24, which is disposed between the first geometric phase element 3 and the display panel 1. The third geometric phase element 24 and the first geometric phase element 3 have the same deflection angle for the light emission path but different deflection directions, and respond to light with different polarization directions respectively; in the first conversion mode, the third geometric phase element 24 is in a transmission state, and the incident light A is perpendicularly transmitted through the third geometric phase element 24 to form the first circularly polarized light B and emitted; in the second conversion mode, the third geometric phase element 24 is in a deflection state, and the incident light A is converted by the third geometric phase element 24 to form the second circularly polarized light C and emitted.

[0074] It should be noted that this application does not impose specific restrictions on the polarization direction of the first geometric phase element 3 and the third geometric phase element 24 that generate the response. It is assumed that the first geometric phase element 3 responds to right-hand circularly polarized light and the third geometric phase element 24 responds to left-hand circularly polarized light.

[0075] In this embodiment, the incident light A is a left-handed circularly polarized ray. In the first conversion mode, the left-handed circularly polarized ray is perpendicularly transmitted through the third geometrical phase element 24 to form the first circularly polarized light B. In the second conversion mode, the left-handed circularly polarized ray is converted by the third geometrical phase element 24 into a right-handed circularly polarized ray and refracted out to form the second circularly polarized light C. Since the first geometrical phase element 3 responds to right-handed circularly polarized light, the first circularly polarized light B can also be perpendicularly transmitted through the first geometrical phase element 3 to form the first outgoing light D. The second circularly polarized light C is converted by the first geometrical phase element 3 into a left-handed circularly polarized ray and exits. Since the third geometrical phase element 24 and the first geometrical phase element 3 have the same deflection angle and different deflection directions for the light exit path, the second circularly polarized light C is also perpendicularly emitted from the first geometrical phase element 3 to form the second outgoing light E. Thus, the second circularly polarized light C is translated relative to the first circularly polarized light B.

[0076] In one embodiment, please refer to Figure 9 and Figure 10 The third geometric phase element 24 includes two third substrates 241 disposed opposite to each other, and a third liquid crystal layer 242 disposed between the two third substrates 241. At least one of the third substrates 241 is provided with a third electrode layer 243. In the first conversion mode, the third electrode layer 243 is energized, and the liquid crystal molecules of the third liquid crystal layer 242 are deflected to form a field-aligned catamaran phase, so that the incident light A is perpendicularly transmitted through the third liquid crystal layer 242. In the second conversion mode, the electrode layer 243 is de-energized, and the liquid crystal molecules of the third liquid crystal layer 242 are in an initial state, so as to convert the emission path and polarization direction of the incident light A.

[0077] This application does not impose specific limitations on the structure of the first geometrical phase element 3. In one embodiment, the first geometrical phase element 3 is a Bragg grating structure, wherein a small amount of chiral dopant is added to the first geometrical phase element 3. The Bragg grating structure can achieve zero diffraction efficiency for a certain incident light, causing it to exit perpendicularly with an unchanged rotation direction, and a certain diffraction efficiency for incident light with another rotation direction, causing the exited light to be polarized at a certain angle and changing its rotation direction.

[0078] Furthermore, the grating thickness parameter of the first geometric phase element 3 is set to Q, where, λ is the wavelength of light in the medium, d is the thickness of the first geometric phase element 3, Λ is the grating constant, and is the average refractive index; when Q≥1, the first geometric phase element 3 is set as a Bragg grating structure.

[0079] This application does not impose specific limitations on the type of the display screen 100. The display screen 100 can be a liquid crystal display screen 100 or an organic light-emitting diode display screen 100.

[0080] Taking the liquid crystal display screen 100 as an example, the display panel 1 includes a backlight module 11 and a display module 12; the display module 12 is disposed on the light-emitting side of the backlight module 11, and the display module 12 includes an array substrate 121 and a color filter substrate 122 disposed opposite to each other, and a liquid crystal layer disposed between the array substrate 121 and the color filter substrate 122. The color filter substrate 122 includes a substrate 1221, a black matrix 1222 and a color resist layer 1223. The black matrix 1222 is disposed on the side of the substrate 1221 facing the array substrate 121, and the color resist layer 1223 is disposed on the side of the substrate 1221 facing the array substrate 121. The color resist layer 1223 includes a plurality of color resist blocks arranged in an array, and the plurality of color resist blocks are distributed in the black matrix 1222; wherein, each color resist block forms a light-emitting area 1a, and the black matrix 1222 between two adjacent color resist blocks forms a light-shielding area 1b.

[0081] A polarizer 13 is also provided on the side of the display module 12 away from the backlight module 11.

[0082] It is known that the black matrix 1222 between two adjacent color resist blocks forms the light-shielding area 1b; after the incident light A passes through the polarization conversion layer 2 and the first geometric phase element 3, it forms the first emitted light D and the second emitted light E. The first emitted light D corresponds to the light-emitting area 1a, and the emission path of the second emitted light E covers the black matrix 1222. In this way, the influence of the black matrix 1222 on the human eye can be eliminated, the screen-door effect can be alleviated, the resolution of the display screen 100 can be improved, and the imaging quality can be optimized. At the same time, since the deflection angle of the liquid crystal molecules 31 in the first geometric phase element 3 can impart the wavefront phase and deflection angle of the light beam, the user can design geometric phase elements with different phase distributions according to the position arrangement of the black matrix 1222 of the display screen 100, thereby improving the applicability of the product. Furthermore, since the first geometric phase element 3 has an ultra-thin shape factor, with a thickness of only one film thickness, it is beneficial to the thinning of the display screen 100 and the VR display device.

[0083] Secondly, embodiments of this application provide a VR display device 1000, please refer to... Figure 11The VR display device 1000 includes a display screen 100 and a frame 200 disposed around the display screen 100. It should be noted that the display screen 100 is configured as described above, that is, the display screen 100 has all the embodiments of the display screen 100 described above, and the VR display device 1000 also has all the technical features of all the embodiments of the display screen 100 described above, and thus has all the beneficial effects brought by all the technical features, which will not be elaborated here.

[0084] 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.

[0085] The above provides a detailed description of a display screen and VR display device provided in the embodiments of this application. Specific examples have been used 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. 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 screen, characterized in that, include: The display panel includes a plurality of sub-pixels arranged in an array, each sub-pixel forming a light-emitting area and a light-shielding area forming between adjacent sub-pixels; A polarization conversion layer is disposed on the light-emitting side of the display panel. When two adjacent frames are displayed, the polarization conversion layer has a first conversion mode and a second conversion mode, respectively. The polarization conversion layer includes: The first liquid crystal waveplate is located on the light-emitting side of the display panel. The first liquid crystal waveplate is used to change the polarization state of light. When two adjacent frames are displayed, the liquid crystal molecules in the first liquid crystal waveplate have a first deflection angle and a second deflection angle. The second geometric phase element is disposed on the side of the first liquid crystal waveplate away from the display panel; A second liquid crystal waveplate is disposed on the side of the second geometric phase element away from the first liquid crystal waveplate. The second liquid crystal waveplate is used to change the polarization direction of light. When two adjacent frames are displayed, the liquid crystal molecules in the second liquid crystal waveplate have a third deflection angle and a fourth deflection angle; and, A first geometric phase element is disposed on the side of the polarization conversion layer away from the display panel; In the first conversion mode, the incident light emitted by a sub-pixel passes through the polarization conversion layer and forms a first circularly polarized light. The incident light is set as linearly polarized light. The first circularly polarized light is perpendicularly transmitted through the first geometric phase element and forms a first outgoing light. The first outgoing light covers the light-emitting area corresponding to the sub-pixel. In the second conversion mode, incident light emitted from the same sub-pixel passes through the polarization conversion layer and forms a second circularly polarized light. The second circularly polarized light is deflected by the first geometric phase element and forms a second outgoing light. The polarization direction of the second outgoing light is the same as that of the first outgoing light and the outgoing path is parallel. The second outgoing light covers the light-shielding area on the side adjacent to the sub-pixel. In the first conversion mode, the liquid crystal molecules in the first liquid crystal waveplate are at the first deflection angle, the liquid crystal molecules in the second liquid crystal waveplate are at the third deflection angle, and the incident light is converted into the first circularly polarized light and emitted perpendicularly. In the second conversion mode, the liquid crystal molecules in the first liquid crystal waveplate are at the second deflection angle, and the liquid crystal molecules in the second liquid crystal waveplate are at the fourth deflection angle, and the incident light is converted into the second circularly polarized light and refracted out.

2. The display screen as described in claim 1, characterized in that, The second geometric phase element and the first geometric phase element have the same deflection angle for the light emission path but different deflection directions, and both respond to light with the same polarization direction.

3. The display screen as described in claim 2, characterized in that, The first liquid crystal waveplate includes two first substrates, two first electrode layers and a first liquid crystal layer. The two first electrode layers are respectively disposed on two opposite surfaces of the two first substrates. The first liquid crystal layer is placed between the two first electrode layers. A first preset voltage is applied to the first liquid crystal layer. The second liquid crystal waveplate includes two second substrates, two second electrode layers, and a second liquid crystal layer. The two second electrode layers are respectively disposed on two opposite surfaces of the two second substrates, and the second liquid crystal layer is placed between the two second electrode layers. A second preset voltage is applied to the second liquid crystal layer.

4. The display screen as described in claim 2, characterized in that, The liquid crystal molecules of the first geometric phase element and the second geometric phase element have different orientations but the same tilt angle.

5. The display screen as described in claim 1, characterized in that, The first geometric phase element is configured as a Bragg grating structure.

6. The display screen as described in claim 5, characterized in that, The grating thickness parameter of the first geometric phase element is set to Q, where, λ is the wavelength of light in the medium, d is the thickness of the first geometric phase element, and Λ is the grating constant. The average refractive index; When Q≥1, the first geometric phase element is set as a Bragg grating structure.

7. The display screen as claimed in claim 1, characterized in that, The display panel includes: Backlight module; and, The display module is disposed on the light-emitting side of the backlight module. The display module includes an array substrate and a color filter substrate disposed opposite to each other, and a liquid crystal layer disposed between the array substrate and the color filter substrate. The color filter substrate includes a substrate, a black matrix, and a color resist layer. The black matrix is ​​disposed on the side of the substrate facing the array substrate, and the color resist layer is disposed on the side of the substrate facing the array substrate. The color resist layer includes a plurality of color resist blocks arranged in an array, and the plurality of color resist blocks are distributed within the black matrix. Each of the color resist blocks forms a light-emitting area, and the black matrix between two adjacent color resist blocks forms a light-blocking area.

8. A VR display device, characterized in that, Includes a display screen and a frame disposed around the display screen; The display screen is configured as described in any one of claims 1 to 7.

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