A light field display system based on collimated light and multiple light control

Abstract

The present invention discloses a light field display system based on collimated light and multiple light control, which relates to the field of three-dimensional stereoscopic display. This system is provided with a diaphragm array layer that can limit the light output angle of the light source layer; a square lens array layer that can convert the light emitted by the light source layer into collimated light to ensure the directivity of the light; an orthogonal prism sheet layer to homogenize the light in two dimensions to ensure uniform brightness at all locations in the final display area; a light control grating layer projects pixel light to different positions in space so that the left and right eyes can see different image information to form a stereoscopic vision; a unidirectional diffusion layer is arranged above the light control grating layer to diffusely scatter the light in a single direction to produce the same three-dimensional effect at different positions in the vertical direction; and a diffusion error compensation algorithm is used for reverse compensation to ensure that observers at different positions can obtain a consistent visual experience, and finally present a three-dimensional light field display effect with uniform brightness and low crosstalk.

Description

Technical Field

[0001] The present invention relates to the field of three-dimensional display, and particularly to a light field display system based on collimated light and multiple light control. Background Art

[0002] Display devices enable humans to receive and process information more intuitively by converting various forms of information into visible images. In recent years, with the rapid development of virtual reality, augmented reality, and three-dimensional imaging technologies, three-dimensional display devices have received extensive attention and research due to their ability to provide a more realistic visual experience. Different from traditional two-dimensional displays, three-dimensional displays provide multi-view image information in different directions, enabling observers to visually perceive depth and three-dimensionality, greatly enhancing the immersion and interactivity.

[0003] Autostereoscopic 3D display technology, which allows users to view stereoscopic images without wearing special glasses, has made significant progress in recent years in various fields such as entertainment, education, and healthcare. Compared with traditional 3D display technologies, autostereoscopic 3D display technology offers a higher user experience and broader application prospects. However, there are still many pain points in the current market's autostereoscopic 3D display technology, which limit its popularization and effectiveness in practical applications.

[0004] Autostereoscopic 3D displays typically consist of a backlight system, a liquid crystal display screen, and a beam control device. The liquid crystal display screen itself does not have the property of emitting light and relies on the backlight source for illumination. The performance of the backlight source directly affects the display effect of the entire system, especially its collimation and uniformity. A highly collimated backlight source can provide higher on-axis brightness, thus significantly improving the user's viewing experience. At the same time, collimated light helps prevent light from escaping into non-observation areas, improving the energy utilization efficiency and reducing corresponding energy consumption.

[0005] However, the existing backlight systems have many deficiencies, which seriously affect the performance and user experience of autostereoscopic 3D display systems. First of all, to meet the high requirements of subsequent 3D display devices, many backlight systems need to be specially made, which not only increases the processing difficulty but also significantly raises the manufacturing cost. Secondly, the existing backlight systems are relatively large in size, which is not conducive to the thin design of 3D displays, and this is an obvious drawback for application scenarios that pursue portability and space utilization. In addition, the existing backlight systems perform poorly in terms of light directivity and uniformity, resulting in low-quality 3D images, serious crosstalk between viewpoints, and a greatly reduced viewing experience.

[0006] In this context, developing a backlight that can achieve high collimation and high uniformity while maintaining a thin design is of great significance for the popularization and application of flat-panel autostereoscopic 3D display systems. This new type of backlight can not only significantly improve the brightness and uniformity of the system, reduce crosstalk between viewpoints, but also optimize the overall energy efficiency and reduce manufacturing costs. Through precise control of the light field, the new backlight can provide consistent and high-quality images in different directions, enhancing the user's immersion and viewing experience. In addition, this technology has wide applicability and can be applied to multiple fields such as virtual reality, augmented reality, medical imaging, education, and entertainment, with very broad prospects. Summary of the Invention

[0007] Aiming at the above deficiencies in the prior art, a light field display system based on collimated light and multiple light controls provided by the present invention solves the problems of low image quality and serious crosstalk between viewpoints in existing autostereoscopic 3D displays.

[0008] In order to achieve the above invention objectives, the technical solution adopted by the present invention is as follows:

[0009] Provide a light field display system based on collimated light and multiple light controls, which includes a host computer, and a light source layer, a diaphragm array layer, a square lens array layer, an orthogonal prism sheet layer, a liquid crystal screen layer, a light control grating layer, and a single-direction diffusion layer arranged in sequence from the inside to the outside;

[0010] The light source layer is used to provide a backlight for the light field display system;

[0011] The diaphragm array layer is used to limit the light output angle of the light source layer;

[0012] The square lens array layer includes a plurality of square lenses and is used to convert the light emitted by the light source layer into collimated light;

[0013] The orthogonal prism sheet layer is used to homogenize the light and make the brightness balanced;

[0014] The liquid crystal screen layer is used to load a synthetic image containing multi-angle image information;

[0015] The light control grating layer is used to project the pixel light from the liquid crystal screen layer to different positions in space, so that the left and right eyes can see different image information to form a stereoscopic vision;

[0016] The single-direction diffusion layer is used to diffusely transmit the light in a single direction to produce the same 3D effect at different positions in the vertical direction;

[0017] The host computer is used to generate a synthetic image containing multi-angle image information; load a diffusion error compensation algorithm to perform reverse compensation on the pixel values that generate errors, and eliminate the crosstalk effect brought by the single-direction diffusion layer.

[0018] The beneficial effects of the present invention are as follows: A diaphragm array layer is provided above the light source layer, which can limit the light output angle of the light source layer; A square lens array layer is provided above the diaphragm array layer, which can convert the light emitted by the light source layer into collimated light to ensure the directivity of the light; An orthogonal prism sheet layer is provided above the square lens array layer to homogenize the light in two dimensions and ensure uniform brightness at all parts of the final display area; An LCD layer and a light control grating layer are sequentially provided above the orthogonal prism sheet layer. The light control grating layer projects the pixel light from the LCD layer to different positions in space, enabling the left and right eyes to see different image information respectively to form a stereoscopic vision; A one-way diffusion layer is provided above the light control grating layer to diffuse the light in a single direction and produce the same three-dimensional effect at different positions in the vertical direction; And the diffusion error compensation algorithm is used to perform reverse compensation on the pixel values with errors to eliminate the crosstalk effect brought by the one-way diffusion layer and ensure that observers at different positions can obtain a consistent visual experience, finally presenting a three-dimensional light field display effect with uniform brightness and low crosstalk.

[0019] Further, the light source layer includes a plurality of light-emitting diodes arranged in a matrix or a linear array, and the backlight is white.

[0020] The beneficial effect of adopting the above further solution is that the light-emitting diodes can provide stable white light source support for the entire light field display system.

[0021] Further, a plurality of holes are provided in the diaphragm array layer, and each hole corresponds to a light-emitting diode; By adjusting the aperture and spacing of the holes in the diaphragm array layer, the light is concentrated in the corresponding square lens in the square lens array layer after passing through the diaphragm array layer.

[0022] The beneficial effect of adopting the above further solution is that only one light-emitting diode is covered under a single square lens, ensuring that the light can be effectively transmitted to the corresponding square lens above it after passing through the diaphragm array layer without crosstalking to the other square lenses, limiting the light output angle and reducing the scattering of the light.

[0023] Further, each square lens corresponds to a light-emitting diode; The surface shape of the square lens is a free-form surface or an aspherical surface; The size of the square lens is more than ten times the size of the light-emitting diode; The thickness of the square lens is between 2 mm and 2 cm; The material of the square lens is PMMA or PET, and the refractive index is between 1.49 and 1.60; The parameters of the square lens have the following constraints:

[0024]

[0025] Where f is the focal length of the square lens; R is the radius of curvature of the square lens; Lis the distance from a single light-emitting diode to a square lens represents the tangent function; is the light-emitting angle of a single light-emitting diode; n is the refractive index of the material of the square lens.

[0026] The beneficial effect of adopting the above further solution is: It can ensure that the light forms a collimated beam after passing through the square lens, further reduce the optical aberration caused by the square lens, improve the collimation and uniformity of the light, and enhance the imaging quality and display performance.

[0027] Furthermore, a single square lens and a single hole in the aperture array layer form a single optical path modulation unit, and the parameters of a single optical path modulation unit have the following constraints:

[0028]

[0029] where represents the arctangent function; d is the diameter of a single hole in the aperture array layer; l is the distance from a single light-emitting diode to the aperture array layer; D is the width of the square lens.

[0030] The beneficial effect of adopting the above further solution is: It can optimize the output of the light, adapt to different light characteristics, and control the angle of the emitted light within a reasonable range

[0031] Furthermore, the orthogonally prismatic lens layer is composed of two prismatic lenses with orthogonally uniform light directions.

[0032] The beneficial effect of adopting the above further solution is: After two different refractions, it can effectively achieve the collimation and diffusion of the light beam, thereby significantly reducing the divergence angle of the emitted light.

[0033] Furthermore, the liquid crystal screen layer is an LCD liquid crystal screen.

[0034] Furthermore, the light control grating layer is composed of multiple longitudinal cylindrical lenses arranged. A single longitudinal cylindrical lens covers at least two sub-pixels of the liquid crystal screen layer; the arc surface of the longitudinal cylindrical lens faces the liquid crystal screen layer, and projects the pixel light from the liquid crystal screen layer to different positions in space, so that the left and right eyes respectively see different image information to form a stereoscopic vision with the following constraints:

[0035]

[0036] where M is the distance between the light control grating layer and the viewing position; m is the distance between the light control grating layer and the liquid crystal screen layer; S is the distance between viewpoints; is the width of the sub-pixels on the liquid crystal screen layer.

[0037] The beneficial effects of adopting the above further solution are as follows: Pixel light from the liquid crystal screen layer can be projected to different positions in space to form parallax, so that a person's two eyes can see images from different angles, thereby generating an out-of-screen effect; at the same time, sufficient optical transmission and light control effects can be ensured to ensure the best view color and light splitting effect.

[0038] Further, the one-way diffusion layer is composed of a plurality of horizontally arranged cylindrical lenses, and the pitch of a single horizontally arranged cylindrical lens is less than the sub-pixel length of the liquid crystal screen layer; the arc surface of the horizontally arranged cylindrical lens faces away from the light control grating layer; the horizontally arranged cylindrical lens and the vertically arranged cylindrical lens are orthogonally arranged.

[0039] The beneficial effects of adopting the above further solution are as follows: The diffusion direction of the horizontal grating and the grating stripe direction of the vertical grating are orthogonally arranged, which can perform one-way diffusion on the light refracted by the vertical grating, ensuring that observers at different positions can obtain a consistent display effect. At the same time, the outgoing angle and diffusion range of the light can be effectively controlled, so that the light after multiple refractions and diffusions forms a uniform and highly realistic light field in the observation space, thereby improving the stability of the stereoscopic display and the consistency of the viewing angle.

[0040] Further, a diffusion error compensation algorithm is loaded to perform reverse compensation on the pixel values that generate errors. The specific method for eliminating the crosstalk effect brought by the one-way diffusion layer is as follows:

[0041] When the difference in gray values of adjacent sub-pixels in the direction perpendicular to the horizontally arranged cylindrical lens under the same horizontally arranged cylindrical lens exceeds the threshold, reverse compensation is performed on the gray value of the next sub-pixel of the adjacent sub-pixels, and the corresponding expression is:

[0042]

[0043] where is the pixel gray value of the sub-pixel at is the pixel gray value of the sub-pixel at the sub-pixel at and the sub-pixel at are adjacent sub-pixels in the direction perpendicular to the horizontally arranged cylindrical lens under the same horizontally arranged cylindrical lens; is the gray value of the next sub-pixel of the sub-pixel at is the gray value of the next sub-pixel at after reverse compensation for the next sub-pixel at is The grayscale value after reverse compensation for the next sub-pixel at ; when in the formula where takes "-", in the formula where takes "+"; when ; when in the formula where takes "+", in the formula where takes "-".

[0044] The beneficial effect of adopting the above further solution is that by performing reverse compensation on specific pixel values (pixel values that generate errors) and maintaining the pixel information in the vertical direction unchanged, the overall visual effect can be ensured to be stable and unchanged, thereby enhancing the three-dimensional stereoscopic perception of the displayed object and forming a high-fidelity and low-crosstalk stereoscopic image. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 is a schematic structural diagram of the present system;

[0046] Figure 2 is a schematic structural diagram of the aperture array layer;

[0047] Figure 3 is a schematic structural diagram of the square lens array layer;

[0048] Figure 4 is a schematic diagram of parameter constraints of the optical path modulation unit;

[0049] Figure 5 is a schematic structural diagram of the orthogonal prism lens layer;

[0050] Figure 6 is a schematic diagram of the optical path regulation effect;

[0051] Figure 7 is a compensation schematic diagram of the diffusion error compensation algorithm.

[0052] Among them: 1. Light source layer; 2. Aperture array layer; 3. Square lens array layer; 4. Orthogonal prism lens layer; 5. Liquid crystal screen layer; 6. Light control grating layer; 7. Unidirectional diffusion layer. DETAILED DESCRIPTION OF THE INVENTION

[0053] The following describes the specific embodiments of the present invention to facilitate those skilled in the art of the present technology to understand the present invention. However, it should be clear that the present invention is not limited to the scope of the specific embodiments. For those of ordinary skill in the art of the present technology, as long as various changes are within the spirit and scope of the present invention defined and determined by the appended claims, these changes are obvious, and all inventions created using the concept of the present invention are within the scope of protection.

[0054] As Figure 1 shown, the light field display system based on collimated light and multiple light control includes a host computer, and a light source layer 1, a diaphragm array layer 2, a square lens array layer 3, an orthogonal prism sheet layer 4, a liquid crystal screen layer 5, a light control grating layer 6, and a one-way diffusion layer 7 arranged in sequence from the inside out;

[0055] The light source layer 1 is used to provide a backlight source for the light field display system;

[0056] The diaphragm array layer 2 is used to limit the light output angle of the light source layer 1;

[0057] The square lens array layer 3 includes a plurality of square lenses and is used to convert the light emitted by the light source layer 1 into collimated light;

[0058] The orthogonal prism sheet layer 4 is used to homogenize the light and make the brightness balanced;

[0059] The liquid crystal screen layer 5 is used to load a synthetic image containing multi-angle image information;

[0060] The light control grating layer 6 is used to project the pixel light from the liquid crystal screen layer 5 to different positions in space, so that the left and right eyes can see different image information respectively to form a stereoscopic vision;

[0061] The one-way diffusion layer 7 is used to diffuse the light in a single direction and produce the same three-dimensional effect at different positions in the vertical direction;

[0062] The host computer is used to load a light field encoding algorithm to generate a synthetic image containing multi-angle image information; load a diffusion error compensation algorithm to perform reverse compensation on the pixel values with errors and eliminate the crosstalk effect brought by the one-way diffusion layer.

[0063] The light source layer 1 includes a plurality of light-emitting diodes arranged in a matrix or a linear array, and the number can vary from dozens to thousands according to actual application requirements. The distance between adjacent light-emitting diodes should ensure the same distance as the square lens above, so that only one light-emitting diode is covered under a single square lens. The brightness of the light-emitting diode can be adjusted by the power provided by the power supply, and it should be kept between 30 lm and 500 lm to ensure appropriate visual brightness and provide stable white light source support for the entire light field display system.

[0064] As Figure 2As shown, multiple holes are provided in the aperture array layer 2, and each hole corresponds to a light-emitting diode; by adjusting the aperture and spacing of the holes in the aperture array layer 2, the light is concentrated in the corresponding square lens in the square lens array layer 3 after passing through the aperture array layer 2, thereby reducing crosstalk and improving the uniformity and directivity of the light. The shape of each hole can be but is not limited to being circular, and can be finely adjusted according to the actual situation to adapt to different light characteristics, so that the angle of the emitted light is controlled within a reasonable range.

[0065] Each square lens corresponds to a light-emitting diode; as Figure 3 shown, the surface shape of the square lens is a free-form surface or an aspherical surface, which can significantly reduce optical aberration and improve the collimation and uniformity of light; the size of the square lens is more than ten times the size of the light-emitting diode to ensure that the lens can effectively collect and collimate the light emitted by the light-emitting diode; the thickness of the square lens is between 2 mm and 2 cm to balance optical performance and mechanical strength; the material of the square lens is PMMA (polymethyl methacrylate) or PET (polyethylene terephthalate), and the refractive index is between 1.49 and 1.60 to ensure the effective collimation and transmission of light; the thickness of the square lens, together with the size and material refractive index, affects the refraction of light and directly affects the final display effect. The parameters of the square lens have the following constraints:

[0066]

[0067] where f is the focal length of the square lens; R is the radius of curvature of the square lens; L is the distance from a single light-emitting diode to the square lens represents the tangent function; is the light-emitting angle of a single light-emitting diode; n is the material refractive index of the square lens.

[0068] By adjusting the parameters, it can be ensured that the light forms a collimated beam after passing through the square lens, further reducing the optical aberration caused by the square lens, improving the collimation and uniformity of the light, and is fixed above the aperture array layer 2 through a precision mold, arranged in a matrix or linear array, and the number is the same as the number of light-emitting diodes.

[0069] As Figure 4 shown, a single square lens and a single hole in the aperture array layer 2 form a single optical path modulation unit. In order to ensure that the light can be effectively transmitted to the corresponding square lens above it after passing through the aperture array layer 2 without crosstalking to the remaining lenses, limit the light-emitting angle, reduce the scattering of light, and generate a stable collimated beam, the parameters of a single optical path modulation unit have the following constraints:

[0070]

[0071] wherein represents the arctangent function; d is the diameter of a single hole in the diaphragm array layer 2; l is the distance from a single light-emitting diode to the diaphragm array layer 2; D is the width of the square lens.

[0072] As Figure 5 shown, the orthogonal prism sheet layer 4 is composed of two prism sheets with mutually orthogonal light homogenizing directions. The two prism sheets are designed to be identical and arranged perpendicular to each other, forming a composite optical structure. The purpose is to further collimate and homogenize the light in two dimensions, ensuring uniform brightness across the final display area. This design enables the incident light to be effectively collimated and diffused after two different refractions, thereby significantly reducing the divergence angle of the outgoing light. The design parameters of the first prism sheet and the second prism sheet mainly include the prism apex angle and the refractive index of the material. The selection of these parameters is based on the divergence angle of the incident light and the expected divergence angle of the outgoing light. During design, the above parameters can be precisely adjusted through optical simulation software to ensure the optimal matching with the light source layer 1 and the square lens array, thereby improving the collimation and uniformity of the outgoing light. The design parameters of each prism include the prism apex angle, the refractive index of the material, and the thickness. By adjusting the parameters of the prism sheets, the collimation effect of the light can be homogenized, the divergence angle of the light beam can be reduced, and it is ensured that the light can be evenly distributed in the observation area after passing through the orthogonal prism sheets. At this time, uniform collimated backlight is obtained.

[0073] In this embodiment, the light control grating layer 6 is composed of a plurality of longitudinal cylindrical lenses arranged, and a single longitudinal cylindrical lens covers at least two sub-pixels of the liquid crystal screen layer 5; the liquid crystal screen layer 5 is an LCD liquid crystal screen, which is used to load a synthetic image generated by a light field coding algorithm. This synthetic image contains image information from multiple angles. Through the light splitting effect of the longitudinal cylindrical lens, it is ensured that the information of each sub-pixel can be accurately transmitted to different positions in the viewing space. For the light field coding algorithm, first, different-angle pictures of the object to be displayed are taken by a high-definition camera device or 3D creation software such as blender as a set of parallax maps. Sub-pixels on the LCD liquid crystal screen with the same distance from the optical axis center of a certain lens unit on the light control grating layer 6 will project the light emitted by them to the same area in space after passing through the lens. Therefore, these sub-pixels should be filled with the information of the same parallax map (read all parallax map operation pixels using visual studio + openCV programming and fill them into the corresponding positions of the synthetic map). For this reason, we can determine the relative position relationship between the sub-pixel and the lens it is located in (determine the relative position relationship by the distance from the center position of the sub-pixel to the center of the lens on the light control grating layer 6 where it is located. Pixels with different distances will be projected to different positions in space by the lens on the light control grating layer 6), which can be judged according to the distance from the center position of the sub-pixel to the center of the lens on the light control grating layer 6 where it is located. The number of sub-pixels covered by a lens unit of the light control grating layer 6 can project to the number of different areas in space. Let the width of the sub-pixel area on the LCD liquid crystal screen covered by a lens unit of the light control grating layer 6 in the horizontal direction be , the distance from the center of each sub-pixel to the center of its corresponding light control unit is within interval, the number of viewpoints is n , the corresponding interval for a single pixel is . When the distance from the sub-pixel on the LCD liquid crystal screen to the edge of the corresponding light control grating layer 6 satisfies , the pixel value at the corresponding position of the th parallax map should be assigned. After a complete traversal and filling, the finally obtained synthetic image can make a person's two eyes see images from different angles through the light control effect of the upper light control grating layer 6, thus generating an in-out screen effect, as shown in Figure 6 .

[0074] The arc surface of the longitudinal cylindrical lens faces the liquid crystal screen layer 5, and projects the pixel light from the liquid crystal screen layer 5 to different positions in space, so that the left and right eyes can see different image information respectively to form the constraints of stereoscopic vision as follows:

[0075]

[0076] where M is the distance between the light control grating layer 6 and the viewing position; mis the distance between the light control grating layer 6 and the liquid crystal display layer 5; S is the distance between viewpoints; is the width of the sub-pixels on the liquid crystal display layer 5.

[0077] The one-way diffusion layer 7 is composed of multiple horizontally arranged cylindrical lenses. The pitch of a single horizontally arranged cylindrical lens is less than the length of the sub-pixels of the liquid crystal display layer 5; the arc surface of the horizontally arranged cylindrical lens faces away from the light control grating layer 6; the orthogonal arrangement of the horizontally arranged cylindrical lens and the vertically arranged cylindrical lens mainly serves to diffusely transmit the light refracted by the light control grating layer 6 in a single direction, generating the same three-dimensional effect at different positions in the vertical direction. The design purpose of the one-way diffusion layer 7 is to ensure that observers at different positions can obtain a consistent visual experience, improving the brightness uniformity and stability of the display system.

[0078] Subsequently, the diffusion error compensation algorithm is used to adjust so that the pixel information in the vertical direction remains unchanged to ensure a stable three-dimensional visual effect. When traversing the entire synthesized image, if a single horizontal cylindrical lens can cover more than a single sub-pixel information, different pixel information will be seen at different angles in this light control direction. The diffusion error compensation algorithm is used to compensate and adjust it. As Figure 7 shown, a coordinate system is established with the upper left corner of the synthesized image as the vertex, the horizontal direction as the x-axis, and the vertical direction as the y-axis. When the difference in gray values between adjacent sub-pixels perpendicular to a horizontal cylindrical lens under the same horizontal cylindrical lens exceeds a threshold (set to 25 in this embodiment), the gray value of the next sub-pixel of the adjacent sub-pixel is compensated in the opposite direction. The corresponding expression is:

[0079]

[0080] where is the pixel gray value of the sub-pixel at is the pixel gray value of the sub-pixel at the sub-pixel at and the sub-pixel at are adjacent sub-pixels perpendicular to the same horizontal cylindrical lens; is the gray value of the next sub-pixel of the sub-pixel at is the gray value of the next sub-pixel at after reverse compensation; is the gray value of the next sub-pixel of the sub-pixel at when in the formula of takes "-", The “ ” in the formula takes “+”; when , the “ ” in the formula takes “+”, and the “ ” in the formula takes “-”.

[0081] In the specific implementation process, the present light field display system is applicable to a variety of scenarios, including large-screen three-dimensional display (such as cinemas, exhibition halls, etc.), virtual reality and augmented reality, medical devices (such as surgical simulation, medical imaging, etc. to provide high-precision three-dimensional display), and home entertainment devices.

[0082] In summary, the present invention is provided with a diaphragm array layer 2 above the light source layer 1, which can limit the light output angle of the light source layer 1; a square lens array layer 3 is provided above the diaphragm array layer 2, which can convert the light emitted by the light source layer 1 into collimated light to ensure the directivity of the light; an orthogonal prism sheet layer 4 is provided above the square lens array layer 3 to equalize the light in two dimensions to ensure uniform brightness at each location in the final display area; an LCD layer 5 and a light control grating layer 6 are sequentially provided above the orthogonal prism sheet layer 4, and the pixel light from the LCD layer 5 is projected to different positions in space through the light control grating layer 6, so that the left and right eyes respectively see different image information to form a stereoscopic vision; a unidirectional diffusion layer 7 is provided above the light control grating layer 6 to diffuse the light in a single direction to further equalize and refine the light; and the pixel values are reversely compensated through a diffusion error compensation algorithm to ensure that observers at different positions can obtain a consistent visual experience, and finally present a three-dimensional light field display effect with uniform brightness and low crosstalk.

Claims

1. A light field display system based on collimated light and multiple light control, characterized in that: It includes a host computer, and a light source layer, an aperture array layer, a square lens array layer, an orthogonal prism layer, a liquid crystal screen layer, a light control grating layer, and a unidirectional diffusion layer which are arranged in sequence from the inside to the outside; A light source layer, used to provide a backlight source for the light field display system; The aperture array layer is used to limit the light output angle of the light source layer; A square lens array layer, comprising a plurality of square lenses, for converting the light emitted by the light source layer into collimated light; Orthogonal prism sheet layer, used to homogenize the light and balance the brightness; The liquid crystal screen layer is used to load a composite image containing multi-angle image information; The light-controlling grating layer is used to project the pixel light from the liquid crystal screen layer to different positions in space, so that the left and right eyes can see different image information respectively to form a stereoscopic vision; The unidirectional diffusion layer is used to diffuse the light in one direction, producing the same three-dimensional effect at different positions in the vertical direction; The host computer is used to generate a composite image containing multi-angle image information; the diffusion error compensation algorithm is loaded to reversely compensate the pixel values ​​that produce errors, eliminating the crosstalk effect caused by the single diffusion layer; The light-controlling grating layer is composed of a plurality of longitudinal cylindrical lenses arranged in an array, and a single longitudinal cylindrical lens covers at least two sub-pixels of the liquid crystal screen layer; the arc surface of the longitudinal cylindrical lens faces the liquid crystal screen layer, and projects the pixel light from the liquid crystal screen layer to different positions in space, so that the left and right eyes see different image information respectively to form the constraints of stereoscopic vision as follows: in M is the distance between the light-controlling grating layer and the viewing position; m is the distance between the light-control grating layer and the liquid crystal screen layer; S is the distance between viewpoints; is the width of the sub-pixel on the LCD layer; The unidirectional diffusion layer is composed of a plurality of transverse cylindrical lenses arranged in an array, the pitch of a single transverse cylindrical lens is smaller than the sub-pixel length of the liquid crystal layer; the arc surface of the transverse cylindrical lens faces the side away from the light control grating layer; the transverse cylindrical lens and the longitudinal cylindrical lens are arranged orthogonally.

2. The light field display system based on collimated light and multiple light control according to claim 1, characterized in that: The light source layer includes a plurality of light emitting diodes arranged in a matrix or a linear array, and the backlight is white.

3. The light field display system based on collimated light and multiple light control according to claim 2, characterized in that: A plurality of holes are arranged in the aperture array layer, each hole corresponds to a light emitting diode; by adjusting the aperture and spacing of the holes in the aperture array layer, the light is concentrated in the corresponding square lens in the square lens array layer after passing through the aperture array layer.

4. The light field display system based on collimated light and multiple light control according to claim 3, characterized in that: Each square lens corresponds to a light-emitting diode; the surface of the square lens is a free-form surface or an aspherical surface; the size of the square lens is more than ten times the size of the light-emitting diode; the thickness of the square lens is between 2 mm and 2 cm; the material of the square lens is PMMA or PET, and the refractive index is between 1.49 and 1.60; the parameters of the square lens have the following constraints: in f is the focal length of the square lens; R is the radius of curvature of the square lens; L is the distance from a single LED to the square lens represents the tangent function; is the light output angle of a single light emitting diode; n is the material refractive index of the square lens.

5. The light field display system based on collimated light and multiple light control according to claim 4, characterized in that: A single square lens and a single hole in the aperture array layer constitute a single optical path modulation unit. The parameters of the single optical path modulation unit have the following constraints: in represents the inverse tangent function; d is the diameter of a single hole in the aperture array layer; l is the distance from a single light-emitting diode to the aperture array layer; D is the width of the square lens.

6. The light field display system based on collimated light and multiple light control according to claim 1, characterized in that: The orthogonal prism sheet layer is composed of two prism sheets whose light uniformity directions are orthogonal to each other.

7. The light field display system based on collimated light and multiple light control according to claim 1, characterized in that: The liquid crystal screen layer is an LCD liquid crystal screen.

8. The light field display system based on collimated light and multiple light control according to claim 1, characterized in that: The specific method of loading the diffusion error compensation algorithm to reversely compensate the pixel value that generates the error and eliminate the crosstalk effect caused by the single diffusion layer is as follows: When the grayscale value difference between adjacent sub-pixels perpendicular to the transverse cylindrical lens under the same transverse cylindrical lens exceeds a threshold, the grayscale value of the next sub-pixel of the adjacent sub-pixel is reversely compensated. The corresponding expression is: in for The pixel grayscale value of the sub-pixel at ; for The pixel grayscale value of the sub-pixel at ; The sub-pixel and The sub-pixels at are adjacent sub-pixels under the same transverse cylindrical lens and perpendicular to the direction of the transverse cylindrical lens; for The grayscale value of the next sub-pixel of the sub-pixel at ; for The gray value of the next sub-pixel at the position after reverse compensation; for The grayscale value of the next sub-pixel of the sub-pixel at ; for The gray value of the next sub-pixel after reverse compensation; hour, The " "Pick"-", The " "Take" + "; when hour, The " "Take"+", The " "Pick"-".

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