A multi-focal 3D floating information display system

Abstract

A multi-focal-plane 3D floating information display system comprises a parallel light source, an LCD display screen, a multi-focal-plane light modulator and an imaging lens. The parallel light source is used to provide the light source required by the 3D floating information display system; the LCD display screen is used to provide the image information in the 3D floating information display system; the multi-focal-plane light modulator is used to spatially modulate the incident image information to form multi-focal-plane imaging and realize the reproduction of stereoscopic image information; and the imaging lens is used to form the stereoscopic 3D floating display visual effect. The image loaded by the LCD display screen is the image of a 3D object at different depths of field, and the corresponding pixels are aligned with the pixels on the multi-focal-plane light modulator. After being modulated by the corresponding stripe grating on the multi-focal-plane light modulator, the multi-depth-of-field image information is spatially separated, and the image is reconstructed at multiple focal planes in front of the LCD display screen to form the 3D floating information display effect.

Description

Technical Field

[0001] This invention relates to the field of 3D display technology, and in particular to a multi-focal 3D floating information display system. Background Technology

[0002] Vision is the primary source of information for people to acquire knowledge of the world. A 1967 study by Trétonra (France) proposed that 83% of human understanding of the world comes from visual information. Everything in the real world is three-dimensional, while traditional displays can only show two-dimensional images. This lack of depth significantly limits our observation and understanding of this complex physical space. Furthermore, nearly 50% of our brain's function is dedicated to processing visual information; the two-dimensional images displayed on a monitor greatly reduce the brain's utilization. Therefore, three-dimensional display has become a higher pursuit for human beings.

[0003] 3D displays offer a comprehensive, three-dimensional visual impact and are considered one of the ultimate goals of information display technology. However, most current 3D display technologies suffer from visual fatigue caused by the vergence-accommodation conflict (VAC). VAC refers to the discrepancy between the convergence of the eyes and the accommodation of the lens in responding to target distance information; that is, the problem arises because the convergence position of the two eyes differs from the focusing position of the single eye. Prolonged viewing of 3D images while in a state of VAC conflict can lead to symptoms such as eye strain, dizziness, and nausea, severely impacting the 3D stereoscopic visual experience and hindering the market promotion of 3D display technology. Therefore, the VAC problem is one of the key issues that needs to be addressed in current 3D information display technology. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide a 3D information display system based on the multi-focal plane imaging principle, which can form multiple imaging focal planes within the field of view, ensuring the consistency of target information distance between the human eye's convergence and the lens's accommodation response, greatly alleviating the visual fatigue problem caused by the convergence-accommodation contradiction, and achieving a 3D floating display effect without visual fatigue.

[0005] According to the present invention, a multi-focal-plane 3D levitation information display system is proposed, comprising a parallel light source, an LCD display screen, a multi-focal-plane light modulator, and an imaging lens. The parallel light source provides the light source required for the 3D levitation information display system; the LCD display screen provides image information for the 3D levitation information display system; the multi-focal-plane light modulator spatially modulates the incident image information to form multi-focal-plane imaging, thereby reproducing stereoscopic image information; and the imaging lens is used for human eye imaging to form a stereoscopic 3D levitation display visual effect.

[0006] Furthermore, the parallel light source is incident at an angle to prevent the influence of zero-order interference light on the imaging effect. The parallel light source can be formed by combining multiple point light sources and then collimating them with a lens, or it can be formed by a single high-power light source after collimation.

[0007] Furthermore, the image information loaded on the LCD display screen is composed of different depth-of-field image information of the 3D object arranged and combined through a certain encoding, wherein the number of image pixels is equal to the sum of the number of pixels of each depth-of-field image. The different depth-of-field images of the 3D object can be extracted by a computer based on image information, or they can be captured by a camera.

[0008] Furthermore, the multi-focal surface light modulator is composed of multiple sets of pixel arrays, which are interlocked with each other and uniformly distributed on the light-emitting surface of the multi-focal surface light modulator. The light emitted by the same set of pixel arrays converges on the focal plane with the same depth of field, while the light emitted by different sets of pixel arrays converges on the focal plane with different depths of field. The multiple sets of pixel arrays together form multi-focal surface imaging to reproduce a three-dimensional information image.

[0009] Furthermore, each pixel unit in the multi-focal surface light modulator is filled with a striped grating. The period and orientation angle of the striped grating satisfy a specific calculation formula. The parameters of each striped grating can be calculated based on the incident light angle and the position of the imaging focal plane. The striped grating is emitted in a transmission mode.

[0010] Specifically, the period Λ and orientation angle of the fringe grating The following relationship is satisfied, where the orientation angle is... The angle between the direction of the grating groove and the y-axis:

[0011]

[0012]

[0013]

[0014]

[0015] Among them, c 2 =a 2 +b 2 +2ab cos(θ1-θ2),θ1=tan -1 (cosβ1 / cosα1)+π / 2,θ2=tan -1(cosβ2 / cosα2)+π / 2; a, b, and c are intermediate values, θ1 and θ2 are intermediate angles; λ is the incident light wavelength; α1, β1, and γ1 are the angles between the incident light and the x-axis, y-axis, and z-axis, respectively; α2, β2, and γ2 are the angles between the diffracted light and the x-axis, y-axis, and z-axis, respectively. After specifying the incident light wavelength, incident angle, and diffracted light angle, the required fringe grating period and orientation angle are calculated using the above four formulas.

[0016] Furthermore, the imaging lens is used to image the focal plane image information with the human eye. The imaging lens operates on the principle of lens imaging. After passing through the imaging lens, the user can view the 3D floating image in front of the display screen.

[0017] Furthermore, this invention proposes to use a multi-focal plane imaging principle, combining an LCD display screen and a multi-focal plane light modulator to form a 3D floating display effect.

[0018] The advantages of this invention are as follows: First, the multifocal surface light modulator can separate combined image information of different depths of field loaded on the LCD, reproducing the image information of 3D objects at different depths of field in front of the LCD screen, forming a multifocal surface 3D floating display effect. This is a true 3D display technology that solves the contradiction between convergence and asymmetry in 3D displays, greatly alleviating visual fatigue. Second, the multifocal surface light modulator is composed of planar striped grating pixels, which can be customized to specific specifications and sizes according to the pixel size of the LCD screen, thus ensuring good alignment and bonding with the LCD screen. Compared with traditional multi-layer liquid crystal-based multifocal surface 3D display technology, the solution proposed in this invention has a simpler and more compact structure, is more practical, and is more suitable for market application, especially in fields such as medical, military, advertising, and gaming entertainment. Attached Figure Description

[0019] The above and / or additional aspects and advantages of the embodiments of the present invention will become apparent and readily understood from the description of the embodiments in conjunction with the following drawings, wherein:

[0020] Figure 1 This is a structural diagram of the striped grating in the XY plane;

[0021] Figure 2 yes Figure 1 The structural diagram of the striped grating in the XZ plane;

[0022] Figure 3 This is a schematic diagram illustrating the working principle of a multifocal surface light modulator according to an embodiment of the present invention;

[0023] Figure 4 This is a schematic diagram of a multi-focal surface display system according to an embodiment of the present invention;

[0024] Figure 5 This is a schematic diagram of a multi-focal 3D floating information display system according to an embodiment of the present invention. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] As described in the background section, the convergence-accommodation contradiction has long hindered the development and market application of 3D display technology. Multifocal plane 3D display technology can effectively solve this core problem, gaining favor among those skilled in the art and becoming one of the technologies most likely to be widely applied in 3D display systems in the future. This invention combines diffraction optics theory with multifocal plane imaging technology to form a highly compact and practical multifocal plane 3D levitation information display system.

[0027] Please refer to [the website / information] first. Figure 1 and Figure 2 , Figure 1 and Figure 2 This is a schematic diagram of a fringe grating in the XY and XZ planes. According to the theory of optical diffraction, the orientation angle of fringe grating 101... The period Λ satisfies the following relationship:

[0028]

[0029]

[0030]

[0031]

[0032] in:

[0033] c 2 =a 2 +b 2 +2ab cos(θ1-θ2);

[0034] θ1=tan -1 (cosβ1 / cosα1)+π / 2;

[0035] θ2=tan -1 (cosβ2 / cosα2)+π / 2;

[0036] a, b, and c are intermediate values; θ1 and θ2 are intermediate angles; λ is the incident light wavelength; α1, β1, and γ1 are the angles between the incident light 201 and the x-axis, y-axis, and z-axis, respectively; α2, β2, and γ2 are the angles between the diffracted light 202 and the x-axis, y-axis, and z-axis, respectively. In other words, after specifying the incident light wavelength, incident angle, and diffracted light angle, the required fringe grating period and orientation angle can be calculated using the above four formulas.

[0037] Based on the above principle, after creating multiple sets of customizable stripe grating pixels on the light-emitting surface of a multifocal light modulator, spatial separation and reconstruction of the image information loaded on the LCD screen can be performed, and a three-dimensional image information can be reproduced in front of the LCD screen.

[0038] The technical solution of this invention is as follows: the multi-depth image source pixels loaded on the LCD screen are aligned with the pixels on the multi-focal plane light modulator. After corresponding stripe grating modulation, the multi-depth image information is spatially separated, and the image is reconstructed on multiple focal planes in front of the LCD screen to form a reproduction of 3D object information. The parameters of the stripe grating pixel structure included in the multi-focal plane light modulator satisfy the equations (1)-(4) obtained above. The stripe grating pixel array is used to spatially separate and reconstruct the loaded image. Each group of stripe grating pixels can project an image of a specific depth onto a focal plane at a specific distance from the LCD screen. Multiple groups of stripe grating pixels can project images of different depths onto focal planes at different distances from the LCD screen. Continuous focal planes form images of continuous depth. Through the imaging lens, the human eye can observe the 3D stereoscopic image. Since this invention adopts the multi-focal plane imaging principle, it can solve the contradiction between convergence and accommodation in 3D display and achieve a true 3D display effect without visual fatigue.

[0039] The following is a detailed description of the specific implementation of the technical solution of the present invention.

[0040] Please refer to Figure 3 , Figure 3This is a schematic diagram illustrating the working principle of a multi-focal plane light modulator according to an embodiment of the present invention. The multi-focal plane light modulator 301 is composed of multiple groups of striped grating pixels (e.g., groups 302-304). Each group of striped grating pixels modulates to form a different focal plane; for example, group 302 forms focal plane 1, group 303 forms focal plane 2, and group 304 forms focal plane 3. Specifically, each sub-pixel in each group can form an image point on the focal plane through diffraction. For example, sub-pixels 302(a)-302(c) in group 302 form image points A1-A3 in focal plane 1, sub-pixels 303(a)-303(c) in group 303 form image points B1-B3 in focal plane 2, and sub-pixels 304(a)-304(c) in group 304 form image points C1-C3 in focal plane 3. To achieve this precise projection imaging, the parameters (period and orientation angle) of the striped grating pixels on the multifocal light modulator 301 are different. First, the diffraction angle needs to be determined based on the position coordinates of the striped grating pixels and the position coordinates of the imaging point. Then, the incident light wavelength and incident angle are combined and the diffraction angle is accurately calculated using equations (1)-(4).

[0041] Please refer to Figure 4 , Figure 4This is a schematic diagram of a multi-focal plane display system according to an embodiment of the present invention. The display system includes a light source 401, an LCD display screen 402, a multi-focal plane light modulator 403, and an imaging lens 404. The light source 401 is a plane light wave, incident at a certain angle to provide illumination. The LCD display screen 402 loads multiple image information (e.g., displaying the letters A, B, and C), and the sub-pixels corresponding to each image are aligned and fitted with each group of pixels in the multi-focal plane light modulator 403. Each group of pixels in the multi-focal plane light modulator 403 can be imaged on different focal planes. For example, the image sub-pixels 402(c) and 402(d) corresponding to the letter A displayed on the LCD screen 402 are respectively aligned and bonded to the sub-pixels 403(c) and 403(d) in the pixel group of the multifocal surface light modulator 403; the image sub-pixels 402(b) and 402(e) corresponding to the letter B displayed on the LCD screen 402 are respectively aligned and bonded to the sub-pixels 403(b) and 403(e) in the pixel group of the multifocal surface light modulator 403; and the image sub-pixels 402(a) and 402(f) corresponding to the letter C displayed on the LCD screen 402 are respectively aligned and bonded to the sub-pixels 403(a) and 403(f) in the pixel group of the multifocal surface light modulator 403. Since pixels 403(c) and 403(d) in the pixel group are imaged on focal plane 1, pixels 403(b) and 403(e) in the pixel group are imaged on focal plane 2, and pixels 403(a) and 403(f) in the pixel group are imaged on focal plane 3, the human eye can view different image information on different focal planes through the imaging lens 404 (for example, the image of the letter A is viewed on focal plane 1, the image of the letter B is viewed on focal plane 2, and the image of the letter C is viewed on focal plane 3), thus achieving a multi-focal plane display imaging effect.

[0042] Please refer to Figure 5 , Figure 5This invention relates to a multi-focal-plane 3D levitation information display system. The system includes a light source 501, an LCD display screen 502, a multi-focal-plane light modulator 503, and an imaging lens 504. The light source 501 is a plane light wave, incident at a certain angle to provide illumination. The LCD display screen 502 loads mixed image information of different depths of the 3D object, and the sub-pixels corresponding to each depth image are aligned and bonded to each group of pixels in the multi-focal-plane light modulator 503. For example, the image sub-pixels 502(c) and 502(d) corresponding to the image displayed on the LCD display 502 (e.g., the rear part of the cylinder) are respectively aligned and bonded to the sub-pixels 503(c) and 503(d) in the pixel group of the multi-focal surface light modulator 503; the image sub-pixels 502(b) and 502(e) corresponding to the image displayed on the LCD display 502 (e.g., the intersection of the cylinder and the cube) are respectively aligned and bonded to the sub-pixels 503(b) and 503(e) in the pixel group of the multi-focal surface light modulator 503; the image sub-pixels 502(a) and 502(f) corresponding to the image displayed on the LCD display 502 (e.g., the front part of the cube) are respectively aligned and bonded to the sub-pixels 503(a) and 503(f) in the pixel group of the multi-focal surface light modulator 503. Because each pixel group in the multifocal plane modulator 503 can be modulated and imaged onto different focal planes (depths of field), 3D image information can be reproduced at different depths of field. Imaged by the imaging lens 404, the human eye can view a suspended 3D stereoscopic image (e.g., a combination of a cylinder and a cube) in front of the LCD display screen. By optimizing the design to create a continuous focal plane distribution, a high-definition true 3D display effect can be achieved.

[0043] The multifocal surface light modulator described above in this invention has a striped grating on its light-emitting surface that can be fabricated using photolithography and nanoimprint lithography. It should be noted that, in this invention, either photolithography can be used to etch striped gratings with different parameters onto the surface of the multifocal surface light modulator, or a mask suitable for imprinting can be first fabricated using photolithography, and then the striped grating pattern can be mass-produced on the multifocal surface light modulator using nanoimprint lithography.

[0044] In summary, this invention discloses a multi-focal-plane 3D levitation information display system. In this invention, the LCD display screen can be replaced by other display screens, such as OLED, Micro-LED, DMD, and other spatial light modulators.

[0045] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0046] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A multi-focal-plane 3D levitation information display system, characterized in that: The system includes a parallel light source, an LCD display screen, a multifocal surface light modulator, and an imaging lens. The parallel light source provides the light source required for the 3D levitation information display system. The LCD display screen provides the image information for the 3D levitation information display system. The multifocal surface light modulator spatially modulates the incident image information to form multifocal imaging, thereby reproducing stereoscopic image information. The imaging lens is used for human eye imaging to create a stereoscopic 3D levitation display visual effect. The image information loaded on the LCD display screen is composed of different depth images of 3D objects arranged and combined in a certain encoding manner, wherein the number of image pixels is equal to the sum of the number of pixels of each depth image; The multifocal plane light modulator is composed of multiple sets of pixel arrays. Each set of pixel arrays is interlocked with each other and uniformly distributed on the light-emitting surface of the multifocal plane light modulator. The light emitted by the same set of pixel arrays converges on the focal plane with the same depth of field, while the light emitted by different sets of pixel arrays converges on the focal plane with different depths of field. The multiple sets of pixel arrays together form multifocal plane imaging to reproduce three-dimensional stereoscopic image information. Each pixel unit in the multifocal surface light modulator is filled with a striped grating, the period Λ and the orientation angle of the striped grating are... The following relationship is satisfied, where the orientation angle is... The angle between the direction of the grating groove and the y-axis: Among them, c 2 =a 2 +b 2 +2abcos(θ1-θ2),θ1=tan -1 (cosβ1 / cosα1)+π / 2,θ2=tan -1 (cosβ2 / cosα2)+π / 2; a, b, and c are intermediate values, θ1 and θ2 are intermediate angles; λ is the incident light wavelength; α1, β1, and γ1 are the angles between the incident light and the x-axis, y-axis, and z-axis, respectively; α2, β2, and γ2 are the angles between the diffracted light and the x-axis, y-axis, and z-axis, respectively. After specifying the incident light wavelength, incident angle, and diffracted light angle, the required fringe grating period and orientation angle are calculated using the above four formulas.

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