A polarization stereoscopic encryption display system

Abstract

The present application relates to a kind of polarized stereoscopic encryption display systems, comprising: quantum dot backlight, pixel polarization selection layer, pixel polarization rotation layer, graphic layer and pixel light field regulation layer are sequentially arranged, and different layers are closely adhered, wherein the quantum dot backlight is used to emit light of different polarization directions, the pixel polarization selection layer is used to pixel polarization screening, the pixel polarization rotation layer is used to dynamically adjust polarization state, the graphic layer is used to load multi-view two-dimensional image, the pixel light field regulation layer is used to accurately guide light of different viewpoints according to the light of multi-view two-dimensional image, and form stereoscopic image.The present application can dynamically allocate completely different exit direction for the incident light of different polarization state under the same pixel unit, so as to seamlessly switch or superimpose multiple high-quality stereoscopic images or encrypted information on the same display plane, realize the dynamic update of encrypted content and the flexible switching of display mode.

Description

Technical Field

[0001] This invention relates to the field of stereoscopic display technology, and in particular to a polarized stereoscopic encrypted display system. Background Technology

[0002] Real three-dimensional objects are perceived through the fusion of light emitted from their surfaces, received by the observer's eyes, and then processed by the brain. In 1991, Adelson EH and Bergen JR first proposed the concept of a phantom light function, which expresses a visible light cone covering an arbitrary wavelength range from any point in space at any time, describing the environmental mapping relationship of all possible scenes. This phantom light function is generally characterized by seven dimensions of light: the observer's position, the deflection angle and azimuth angle of the light, the wavelength of the light, and the observation time.

[0003] Traditional naked-eye 3D display technologies often employ spatially multiplexed pixels for light field modulation, but suffer from limitations in resolution and weak encryption capabilities. While the all-optical function theory provides a foundation for light field description, its precision in light control is insufficient in practical applications. Although polarization technology has been used in 3D cinemas and LCD displays, it struggles to achieve dynamic, high-fidelity effects when combined with stereoscopic encryption. Existing encrypted displays largely rely on software or privacy films, sacrificing display quality.

[0004] In summary, when used for content encryption, polarization-based stereoscopic displays typically only present a single, fixed encrypted image, lacking the ability to dynamically switch and perform real-time encryption. The fundamental reason is that existing systems struggle to flexibly control and match multiple different polarization states and stereoscopic image information on the same display unit via electrical signals. This limits its application in situations requiring high security levels and dynamically updated ciphertext. When applying polarization technology to stereoscopic encrypted displays, existing solutions often pair fixed polarization devices with static stereoscopic images. This static binding prevents the system from dynamically switching between different encrypted stereoscopic images during display, thus limiting security, information capacity, and interactivity. The key issue lies in the lack of a system architecture capable of synchronously and rapidly adjusting the pixel mapping relationship between polarization states and stereoscopic images. Summary of the Invention

[0005] Therefore, the technical problem to be solved by the present invention is to overcome the problem that the existing encryption system can only present a single, fixed encrypted image and lacks a system architecture that can synchronously and quickly adjust the mapping relationship between polarization state and stereoscopic image pixels.

[0006] To address the aforementioned technical problems, this invention provides a polarization-based stereoscopic encrypted display system, comprising a quantum dot backlight, a pixel polarization selection layer, a pixel polarization rotation layer, an image layer, and a pixel light field control layer arranged sequentially, with the different layers tightly bonded together.

[0007] When the quantum dot backlight is used to emit light with different polarization directions, the pixel polarization selection layer is used to filter the polarized light, the pixel polarization rotation layer is used to dynamically adjust the polarization state of the light, the image layer is used to load multi-view two-dimensional images, and the pixel light field control layer is used to precisely guide the light formed by the multi-view two-dimensional images to different viewpoints to form a stereoscopic image.

[0008] In one embodiment of the present invention, the quantum dot backlight includes a blue LED, a quantum dot, a light guide plate, and a phase retardation film arranged sequentially. The blue LED serves as an excitation light source, emitting blue light. The quantum dot, excited by the light emitted by the blue LED, emits red and green light, thereby achieving a wide color gamut coverage. The light guide plate diffuses and homogenizes the light emitted from the blue LED and the quantum dot in a two-dimensional plane, forming a surface light source with uniform brightness. The phase retardation film, by applying a voltage, controls the conversion of unpolarized light or light of a certain polarization state from the light guide plate into linearly polarized light with a specific direction required by the system.

[0009] In one embodiment of the present invention, the pixel polarization selection layer is composed of a metal wire grid.

[0010] In one embodiment of the present invention, the pixel polarization rotation layer includes an indium tin oxide electrode and a liquid crystal material. An alternating voltage is applied to the indium tin oxide electrode of the pixel polarization rotation layer to rotate the liquid crystal molecules in the liquid crystal material, thereby dynamically adjusting the polarization state of light.

[0011] In one embodiment of the present invention, the pixel light field control layer is divided into several pixel units, each pixel unit including several sub-pixels; the sub-pixels with the same relative position in all pixel units constitute a pixel group, each pixel group corresponds to the transmission of light rays with the same polarization direction to the same viewpoint, and different pixel groups correspond to different viewpoints.

[0012] In one embodiment of the present invention, each pixel unit is configured to provide a corresponding sub-pixel for different stereoscopic images when the quantum dot backlight outputs light with different polarization directions.

[0013] In one embodiment of the present invention, each pixel unit includes at least two sub-pixels, and the two sub-pixels correspond to different stereoscopic images;

[0014] The sub-pixel spacing within the pixel unit corresponding to the same stereoscopic image is set to expand the field of view.

[0015] In one embodiment of the present invention, each pixel unit in the pixel light field control layer is a pixel-type nanograting, and the pixel-type nanograting only supports light transmission in a single polarization direction.

[0016] In one embodiment of the present invention, the pixel-type nanograting supports light transmission in only a single polarization direction, and the light transmission of the nanograting satisfies the following wave vector relationship:

[0017] ;

[0018] in, Let be the wave vector of the diffracted light in the pixel light field modulation layer and satisfy the following conditions: , λ is the wavelength of light in a vacuum. Let be the wave vector of the incident light in the pixel light field modulation layer and satisfy... , The refractive index of the pixel light field modulation layer material for the wavelength of light is given. The reciprocal lattice vector of the nanograting and satisfying , The period is the period of the nanograting.

[0019] In one embodiment of the present invention, the period of the nanograting The formula is:

[0020] ;

[0021] in, For wavelength, Let be the refractive index of the phase panel. , , , This is an angle parameter used to precisely modulate the direction of the emitted light.

[0022] Compared with the prior art, the above-described technical solution of the present invention has the following advantages:

[0023] The polarization-based stereoscopic encryption display system described in this invention can present multiple encrypted images when used for content encryption. This invention achieves pixel-level precise light programming through a pixel light field control layer, whose nanostructure satisfies wave vector relationships. This allows the system to dynamically allocate distinctly different exit directions for incident light with different polarization states within the same pixel unit, thereby seamlessly switching or overlaying multiple high-quality stereoscopic images or encrypted information on the same display plane. This enables dynamic updates of encrypted content and flexible switching of display modes, while maintaining a compact overall structure and high compatibility with existing display technologies. Attached Figure Description

[0024] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0025] Figure 1 This is a schematic diagram of the polarization stereoscopic encryption display system structure in an embodiment of the present invention;

[0026] Figure 2 This is a schematic diagram of the quantum dot backlight structure in an embodiment of the present invention;

[0027] Figure 3 This is a display diagram of the light path and stereoscopic image 1 under the adjustable quantum dot backlight output P2 polarized light in an embodiment of the present invention;

[0028] Figure 4 This is a display diagram of the light path and stereoscopic image 2 under the polarized light output P1 of the adjustable quantum dot backlight in this embodiment of the invention;

[0029] Figure 5 This is a schematic diagram of the imaging process of viewpoint 1 corresponding to stereoscopic image 1 in an embodiment of the present invention;

[0030] Figure 6 This is a schematic diagram of the imaging process of viewpoint 1 corresponding to stereoscopic image 2 in an embodiment of the present invention;

[0031] Figure 7 This is a schematic diagram of the pixel distribution of the pixel light field modulation layer in an embodiment of the present invention;

[0032] Figure 8 This is a schematic diagram showing the distribution of pixels at four viewpoints in stereoscopic image 1 in an embodiment of the present invention;

[0033] Figure 9 This is a schematic diagram showing the distribution of pixels at four viewpoints in the stereoscopic image 2 in an embodiment of the present invention;

[0034] Figure 10 This is a schematic diagram illustrating the calculation of nanograting parameters based on the pixel light field modulation layer in an embodiment of the present invention. Detailed Implementation

[0035] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments described are not intended to limit the present invention.

[0036] Example 1

[0037] Reference Figure 1 As shown, this invention relates to a polarized stereoscopic encrypted display system, capable of displaying different stereoscopic images and text under different polarized light, while possessing high color saturation, high brightness, and strong encryption. Figure 1As shown, the device sequentially comprises a quantum dot backlight 1, a pixel polarization selection layer 2, a pixel polarization rotation layer 3, an image layer 4, and a pixel light field modulation layer 5. These layers are tightly integrated using optical adhesive or micro-nano bonding technology to ensure precise control of light transmission. When the quantum dot backlight 1 emits light with different polarization directions, the pixel polarization selection layer 2 filters the polarized light, the pixel polarization rotation layer 3 dynamically adjusts the polarization state of the light, the image layer 4 loads multi-view two-dimensional images, and the pixel light field modulation layer 5 precisely guides the light from the multi-view two-dimensional images to different viewpoints, forming a stereoscopic image. Only through a decoder device with adjustable polarization direction synchronized with the polarization modulation signal of the quantum dot backlight 1 can the target stereoscopic image be viewed, thus achieving information encryption.

[0038] Quantum dot backlight 1 is the core light source of the device, and its structure is as follows: Figure 2 As shown, the backlight consists of a blue LED 1-1, quantum dots 1-2, a light guide plate 1-3, and a phase retardation film 1-4. The blue LED 1-1 serves as the excitation source, emitting blue light. Under the excitation of the light emitted by the blue LED 1-1, the quantum dots 1-2 emit high-purity red and green light with a narrow half-width at half-maximum (FWHM), thus achieving broad color gamut coverage. The light guide plate 1-3 diffuses and homogenizes the light emitted from the point or line light sources of the blue LED 1-1 and quantum dots 1-2 within a two-dimensional plane, forming a uniformly bright surface light source. The phase retardation film 1-4, by applying a voltage, converts the unpolarized light or light of a certain polarization state from the light guide plate 1-4 into linearly polarized light with a specific direction required by the system. The quantum dots 1-2 are made of cadmium selenide (CdSe) nanocrystals, with a FWHM of less than 20 nm, capable of emitting high-purity red and green light, achieving a color gamut coverage of over 120% of NTSC. Phase delay films 1-4 are made of nematic liquid crystal and can output light in the P1 (s-polarization) or P2 (p-polarization) direction by voltage control. The advantages of this design are: high color purity and low power consumption of quantum dot backlight 1; and the adjustable polarization characteristic provides a basic key for encryption.

[0039] The pixel polarization selection layer 2 is located in front of the backlight and is composed of a metal wire grid (linewidth approximately 100nm). In this embodiment, the quantum dot backlight 1 can emit both P1 polarized light (s-light) and P2 polarized light (p-light). For example, when the quantum dot backlight 1 outputs P1 polarized light (s-light), the s-light passes through the pixel polarization selection layer 2 (which has been pre-configured to allow s-light to pass through, its function being to filter out irrelevant polarized light and ambient light, ensuring that the output is pure polarized light) and the pixel polarization rotation layer 3, such as... Figure 3 As shown, the polarization direction remains unchanged. After the s-light passes through the image layer 4 and the pixel light field modulation layer 5, the human eye can perceive a three-dimensional image of the can. Figure 4 As shown, when the pixel polarization rotation layer 3 is activated, the polarization state of the s-light changes from s-light to p-light. After passing through the image layer 4 and the pixel light field modulation layer 5, the human eye can perceive a stereoscopic crocodile image. The pixel polarization rotation layer 3 consists of upper and lower indium tin oxide (ITO) transparent electrodes and a liquid crystal material layer filled between them. Applying an AC voltage to the indium tin electrodes of the pixel polarization rotation layer 3 causes the liquid crystal molecules in the liquid crystal material to rotate, thereby dynamically adjusting the polarization state of the light. Specifically, in P2 light (p-light) mode, an AC 5V voltage needs to be applied to the ITO electrodes to rotate the liquid crystal molecules by 90°, thus converting the s-light into p-light; while in P1 light (s-light) mode, no voltage needs to be applied, the liquid crystal material layer remains in its initial state, and the s-light can pass directly. The advantages of this design are: pixel-level control of polarization selection and rotation achieves encrypted splitting of the light path, and the response time is fast (microsecond level), making it suitable for dynamic scenes.

[0040] Please see Figure 5 Light of different polarization states passes through different positions on the pixel polarization selection layer 2. Quantum dot backlight 1 emits polarized light under P1. After passing through the pixel polarization selection layer 2, only s light can directly pass through the pixel polarization rotation layer 3 and enter the image layer 4 (the image layer 4 is a nano pattern made of a can by photolithography). The viewpoint 1 image of the stereoscopic image 1 is obtained through the pixel light field modulation layer 5.

[0041] Please see Figure 6 Light of different polarization states passes through different positions on the pixel polarization selection layer 2. The quantum dot backlight 1 emits polarized light under P2. After passing through the pixel polarization selection layer 2 and the pixel polarization rotation layer 3, the polarization state changes from p light to s light, and then enters the image layer 4 (the image layer 4 is a nano pattern of a shark made by photolithography). The viewpoint 1 image of the stereoscopic image 2 is obtained through the pixel light field modulation layer 5.

[0042] Pixel light field modulation layer 5 includes multiple pixel units (such as...) Figure 7 As shown in the example (taking four pixel units), each pixel unit consists of several sub-pixels. Sub-pixels with the same relative position in all pixel units form a pixel group, and each group corresponds to a viewpoint. Figure 7 The pixel distribution on pixel light field modulation layer 5 is shown: pixel units one, two, three, and four each contain four sub-pixels 11, 12, 13, and 14. Sub-pixels 11 form the first group of sub-pixels across units, guiding light to viewpoint 1; sub-pixels 12 form the second group, corresponding to viewpoint 2; sub-pixels 13 form the third group, corresponding to viewpoint 3; and sub-pixels 14 form the fourth group, corresponding to viewpoint 4. This grouping ensures that each viewpoint image is contributed by the full resolution, eliminating the need for pixel reuse and avoiding resolution loss.

[0043] The image layer 4 uses a conventional LCD panel and loads two-dimensional image information (such as four viewpoints) generated by a multi-view image algorithm. The pixel light field modulation layer 5 is the core innovation of this invention, and its structure is as follows: Figure 7 As shown, it consists of a pixel-type nanograting array. Each pixel unit contains four sub-pixels 11, 12, 13, and 14. The sub-pixels are silicon-based metasurface structures that only support light transmission in a single polarization direction. For stereoscopic image 1, the pixel distribution at its four viewpoints is as follows. Figure 8 As shown. The first group of sub-pixels (composed of sub-pixels 11 in each unit) supports the transmission of s-light to viewpoint 1; the second group of sub-pixels (sub-pixels 12) corresponds to viewpoint 2; the third group of sub-pixels (sub-pixels 13) corresponds to viewpoint 3; and the fourth group of sub-pixels (sub-pixels 14) corresponds to viewpoint 4. When P1 polarized light is incident, the pixel light field modulation layer 5, through the polarization sensitivity of the metastructure, precisely guides the s-light to these viewpoints, generating a coherent stereoscopic vision. Sub-pixels in the same position in all pixel units form a pixel group (such as the first group of sub-pixels 11), and each group corresponds to a viewpoint (such as viewpoint 1). For the stereoscopic image 2, its viewpoint pixel distribution is as follows. Figure 9 As shown. Similarly, sub-pixels 21, 22, 23, and 24 form four groups of sub-pixels, corresponding to viewpoints 1 to 4. When the P2 polarized light is rotated into s-light, the pixel light field control layer 5 transmits the light to each viewpoint of the stereoscopic image 2 according to the polarization selection characteristics of the sub-pixels, realizing dynamic encryption switching.

[0044] Furthermore, each pixel unit corresponds to at least one display object, and each pixel unit is used to provide a corresponding sub-pixel for different stereoscopic images when the quantum dot backlight 1 outputs light with different polarization directions.

[0045] Furthermore, each pixel unit includes at least two sub-pixels, and the two sub-pixels correspond to different stereoscopic images; the sub-pixels in the pixel unit corresponding to the same stereoscopic image are spaced apart to expand the viewing angle range.

[0046] Figure 10 This is a schematic diagram of the pixel light field modulation layer 5. This layer is typically a metasurface or metagrating structure, with a typical three-layer architecture from bottom to top: a transparent substrate 5-1 (supporting layer, glass), a nanostructure layer 5-2 (functional layer), and an encapsulation cover layer 5-3 (protective layer, PET film, PMMA film). The nanostructure layer 5-2 consists of a series of pixel-type nanograting units arranged according to a specific pattern. In dynamic 3D displays, the pixel light field modulation layer 5 is formed by the combination of pixel-type nanogratings. After the light is modulated by the nanogratings, its emission direction is precisely controlled by the grating diffraction equation. Specifically, the diffracted light wave vector... This directly determines the spatial angle at which light rays emerge, thus guiding the light to different preset viewpoints. The period of the nanograting... Through its reciprocal lattice vector It is regulation The direction, and thus the core structural parameters for precisely designing the light guide to the target viewpoint, are determined by this. Different periods are designed for different pixels or sub-pixel regions. By aligning nanostructures, complex optical field calculations can be achieved, satisfying the following:

[0047] (1)

[0048] in, The wave vector of the diffracted light in the pixel light field modulation layer 5 and satisfying , λ is the wavelength of light in a vacuum. The wave vector of the incident light in the pixel light field modulation layer 5 and satisfying , The refractive index of the pixel light field modulation layer 5 material for the wavelength of light is given. The reciprocal lattice vector of the nanograting and satisfying , The period is the period of the nanograting.

[0049] Period of nanograting The formula is:

[0050] (2)

[0051] in, For wavelength, Let be the refractive index of the phase panel. , , , The angle parameter is used to precisely modulate the direction of the emitted light. The advantages of this design are: it can achieve multi-viewpoint light distribution without pixel reuse, and the resolution remains unchanged; and under different polarized light, the sub-pixel groups guide different images, forming a dense stereoscopic effect.

[0052] The polarization-based stereoscopic encrypted display system of this invention includes a quantum dot backlight 1, a pixel polarization selection layer 2, a pixel polarization rotation layer 3, an image layer 4, and a pixel light field modulation layer 5. It can generate four viewpoint images of different stereoscopic images, allowing the human eye to perceive different stereoscopic images. This device utilizes backlighting and multi-layer modulation to generate different stereoscopic images under different polarized light, and achieves high-resolution multi-viewpoint output through the pixel light field modulation layer. This design not only improves display quality (such as color saturation and brightness) but also provides a reliable physical encryption method, suitable for AR / VR, secure displays, and other fields.

[0053] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A polarization-based stereoscopic encryption display system, characterized in that, It includes a quantum dot backlight (1), a pixel polarization selection layer (2), a pixel polarization rotation layer (3), an image layer (4), and a pixel light field control layer (5) arranged sequentially, and the different layers are closely bonded together. When the quantum dot backlight (1) is used to emit light with different polarization directions, the pixel polarization selection layer (2) is used to filter the light by polarization, the pixel polarization rotation layer (3) is used to dynamically adjust the polarization state of the light, the image layer (4) is used to load multi-view two-dimensional images, and the pixel light field control layer (5) is used to precisely guide the light formed by the multi-view two-dimensional images to different viewpoints to form a stereoscopic image.

2. The polarization stereoscopic encryption display system according to claim 1, characterized in that: The quantum dot backlight (1) includes a blue LED (1-1), a quantum dot (1-2), a light guide plate (1-3), and a phase delay film (1-4) arranged sequentially. The blue LED (1-1) serves as an excitation source, emitting blue light. The quantum dot (1-2) is excited by the light emitted by the blue LED (1-1) and emits red and green light, thereby achieving a wide color gamut coverage. The light guide plate (1-3) diffuses and homogenizes the light emitted from the blue LED (1-1) and the quantum dot (1-2) in a two-dimensional plane, forming a surface light source with uniform brightness. The phase delay film (1-4) controls the conversion of unpolarized light or light of a certain polarization state from the light guide plate (1-3) into linearly polarized light with a specific direction required by the system by applying a voltage.

3. The polarization stereoscopic encryption display system according to claim 1, characterized in that: The pixel polarization selection layer (2) is composed of a metal wire grid.

4. The polarization stereoscopic encryption display system according to claim 1, characterized in that: The pixel polarization rotation layer (3) includes an indium tin oxide electrode and a liquid crystal material. An AC voltage is applied to the indium tin electrode of the pixel polarization rotation layer (3) to rotate the liquid crystal molecules in the liquid crystal material, thereby dynamically adjusting the polarization state of light.

5. The polarization stereoscopic encryption display system according to claim 1, characterized in that: The pixel light field control layer (5) is divided into several pixel units, each pixel unit including several sub-pixels; the sub-pixels with the same relative position in all pixel units constitute a pixel group, each pixel group corresponds to the transmission of light rays with the same polarization direction to the same viewpoint, and different pixel groups correspond to different viewpoints.

6. The polarization stereoscopic encryption display system according to claim 5, characterized in that: Each pixel unit is used to provide a corresponding sub-pixel for different stereoscopic images when the quantum dot backlight (1) outputs light with different polarization directions.

7. The polarization stereoscopic encryption display system according to claim 5, characterized in that: Each pixel unit includes at least two sub-pixels, and the two sub-pixels correspond to different stereoscopic images; Subpixels in the same stereoscopic image corresponding to a pixel unit are set to be adjacent or spaced apart, wherein spaced subpixels are used to expand the field of view.

8. The polarization stereoscopic encryption display system according to claim 6, characterized in that: Each pixel unit in the pixel light field control layer (5) is a pixel-type nanograting, and the pixel-type nanograting only supports light transmission in a single polarization direction.

9. The polarization stereoscopic encryption display system according to claim 8, characterized in that: The pixel-type nanograting supports light transmission in only a single polarization direction, and the light transmission of the nanograting satisfies the following wave vector relationship: ； in, The wave vector of the diffracted light in the pixel light field modulation layer (5) and satisfying , λ is the wavelength of light in a vacuum. The wave vector of the incident light in the pixel light field modulation layer (5) and satisfying , The refractive index of the pixel light field modulation layer (5) material for the wavelength of light is given. The reciprocal lattice vector of the nanograting and satisfying , The period of the nanograting.

10. The polarization stereoscopic encryption display system according to claim 9, characterized in that: The period of the nanograting The formula is: ； in, For wavelength, Let be the refractive index of the phase panel. , , , This is an angle parameter used to precisely modulate the direction of the emitted light.

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