autostereoscopic display screens made in china

In this study, we compared the optical parameters and clinical indexes between the novel clinical dynamic stereopsis assessment based on an autostereoscopic display system and a conventional dynamic random-dot stereopsis measuring instrument. The findings showed that the autostereoscopic device had excellent functions in both physical condition and clinical performance, suggesting the potential for future screening applications and popularization.

Optical parameters including luminance, crosstalk, and spectrum of screening equipment have a huge impact on displaying dynamic clues for clinical dynamic stereopsis assessment (12,13). Existing research shows that stereopsis is diminished over a range of illumination from photopic to scotopic light (21). In our study, the luminance of the autostereoscopic device was clearly within the photopic range, which was classified as good interior lighting (250 cd/m2) (22). However, when participants wore filter glasses, the perceived luminance dropped dramatically, with a 97.33% decrease in the left eye and a 96.91% decrease in the right eye, which caused a loss of stereopsis effects. An early study by Mueller and Lloyd (23) reported that the threshold of stereopsis decreased with changes in the field luminance from 1 cd/m2to the lowest values (3×10-4 cd/m2). Many investigators now believe that stereopsis mainly depends on the level of illumination. Reduced luminance produces a temporal low-pass of neural response, resulting in secondary amplitude reduction and delay, which are particularly disruptive for stereopsis (24). The autostereoscopic device did not suffer a luminance decrease as the conventional instruments did, which demonstrated that the autostereoscopic device had a better ability for dynamic stereopsis assessment.

Screen performance of devices were compared: crosstalk de-camouflages test images. High levels of crosstalk cause a loss of fidelity in stereoscopic images. Therefore, it is crucial to maintain lower crosstalk in the stereo acuity assessment (25,26). Previous research revealed that 45° tilting of the head by participants wearing filter glasses resulted in 100% crosstalk in a random-dot stereopsis test (27). Degradation of stereopsis test accuracy by crosstalk may be associated with a violation of the fundamental principle of the stereo acuity assessment. Therefore, the examinations must exclude monocular cues (e.g., texture gradient, relative size) that would enable participants to perform correctly in the absence of stereo acuity. Crosstalk de-camouflages test images that should be detected only via stereopsis (28,29). In our study, the crosstalk of the new autostereoscopic device was significantly lower than that of the conventional instruments, suggesting that test results with the new approach would be more realistic.

The binocular chromatic aberration caused by filter glasses can also cause serious problems in stereo acuity assessment (30). Conventionally, the right eye observes test images through a red filter which appears red, while the left eye observes the images through a blue filter which appears blue. Although chromatic information could assist in stereopsis (31,32), previous studies have suggested that similarity, rather than difference, of color would extend the range of perceived stereopsis (33). The anti-correlations in color contrast degrades stereopsis (34). Kingdom et al. (35) concluded that it was unnecessary to pre-filter the image into separate color maps before the image underwent stereopsis processing for the visual system. Reports also tend to agree that visual features are somehow given a “label” based on their chromaticities and that stereoscopic matches with the same label are favored over those without (33,36). The conventional instruments had an obsolete chromatic stereopsis mechanism with limited stereo acuity (37). In contrast, the novel autostereoscopic device had a high color restoration degree that presented the dynamic stereopsis as closer to the actual state, which enabled more accurate dynamic assessments of stereopsis.

In the previous research, there was a dynamic stereoscopic measurement based on an autostereoscopic device called Nintendo’s 3DS (38). Compared with our device, there are slight differences in the technical principles of dynamic stereoscopic presentation. The Nintendo’s 3DS is a parallax-barrier autostereoscopic device with no detection floor of high-grade stereo. But would degrade in half the resolution and brightness of the dynamic image received by each eye. Our device is based on directional backlight technology. It ensures that each eye receives the full resolution and brightness of the dynamic image, which could better display dynamic clues for clinical dynamic stereopsis assessment.

Clinically, our autostereoscopic device demonstrated excellent accuracy and repeatability in a three-pattern evaluation. Moreover, according to the stereo acuity distribution comparison, 26 of 135 healthy participants with an abnormal range of stereo were recruited in this study. For this group of people, the accuracy of the device remained stable at a high level. Therefore, we could conclude that this autostereoscopic device had satisfactory precision in both normal stereo acuity and reduced stereo acuity, which was satisfied the requirements of dynamic stereopsis variability in the population assessment.

In terms of subjective evaluations, the autostereoscopic device had a lower fatigue score. We believe that this is mainly due to the advantages of optical parameters compared to conventional instruments. The brighter luminance, lower crosstalk, and higher color restoration degree of directional backlight technology provide separate images to each eye which allows visual representation to be closer to the human senses (39), offering a better stereopsis performance and lessening visual fatigue.

Furthermore, under the same testing protocol, besides higher acceptance and efficiency, the conventional instrument had a sizeable standard deviation of testing time (SD =116 s), indicating that there were substantial differences in adaptation of this examination among participants. In contrast, the autostereoscopic device had a lower standard deviation (SD =58.9 s), suggesting that participants could better understand and master the examination process. We assume that this difference would be mainly caused by the optimization of a user-friendly screening interface. The autostereoscopic device is equipped with interactive software and an eye-tracking camera. Participants can complete the assessments independently without the examiner"s guidance. This not only saves time but adds more fun to the examination procedure, thus increasing efficiency and acceptance.

The novel clinical dynamic stereopsis assessment based on an autostereoscopic display system with excellent optical parameters, such as brighter luminance, lower crosstalk, and higher color restoration degree, could better display dynamic clues for clinical dynamic stereopsis assessment while maintaining equal accuracy as the conventional dynamic random-dot stereopsis measuring instrument does. Moreover, the novel assessment is of higher patient acceptance and lesser visual fatigue compared with the conventional assessment.

The objective of the invention is to propose a kind of lens colour autostereoscopic display apparatus, it is compared with current device and has obtained higher resolution.

This purpose reaches by a kind of auto-stereoscopic display device, this auto-stereoscopic display device comprises the matrix display panel curtain, and be arranged in this display screen the place ahead and have the lens arra of the axis of lens that tilts with respect to the vertical axes of this display screen, this lens arra is designed to receive by the raster image of display screen emission and to it and carries out optical processing, and this raster image is encoded so that a plurality of (P) viewpoint of Same Scene is integrated.

According to the present invention, the image that this display screen is launched is made up of one group of voxel, each voxel is made up of a plurality of (P) viewpoint of the image pixel that is shown scene, and in each voxel, each viewpoint of the image pixel of being discussed is by level code, and three kinds of colors that are associated with each viewpoint of the described image pixel of being discussed are along the coding axle that is basically parallel to the axis of lens, be encoded in triplex row.

The problem utilization display device according to the present invention of equilibrium level and the vertically loss of resolution solves, particularly for many viewpoints of about 8,9 or 10.In fact, opposite with the coding techniques in being used in prior art equipment, in the present invention, on the one hand must the stereoscopic vision problem of handling on the horizontal dimensions and here along actual be that the coding axle of lens arra axle, the color coding problem of handling in triplex row have been carried out actual separation.

-matrix display panel curtain comprises one group of pixel, and each pixel comprises three colors row (RGB), and this screen design becomes to receive the signal that comes the content encoding to N voxel to produce according to a plurality of (P) viewpoint, and

-lens arra comprises a plurality of cylindrical lenss that are arranged in parallel along the axis of lens, and the axle of the row of the described axis of lens and display screen forms predetermined inclination α.

In the preferred embodiment according to auto-stereoscopic display device of the present invention, the electronic display curtain is a plasma screen.

According to a further aspect in the invention, proposed the automatic stereo display packing, it is used for according to auto-stereoscopic display device of the present invention, and this method comprises:

-receive the described image that is shown and it is carried out optical processing by the lens arra that is arranged in described display screen the place ahead and has an axis of lens that tilts with respect to the vertical axes of described display screen, so that long-range generation 3-D view, described raster image are encoded so that a plurality of viewpoints of described image are integrated.

According to the present invention, form by one group of voxel by the image that display screen is launched, each voxel is made up of a plurality of (P) viewpoint of the image pixel of the scene that is shown, and in each voxel, each viewpoint of the image pixel of being discussed is by level code, and three kinds of colors that are associated with each viewpoint of the described image pixel of being discussed are along the coding axle that is basically parallel to the axis of lens, be encoded in triplex row.

-according to according to a plurality of (P) viewpoint to the content of N voxel encode the signal that produces coding, come matrix to show one group of pixel by means of electronic display unit, each pixel all comprises horizontally disposed three color cell (RGB) in this group pixel, and

-producing stereo-picture by the lens arra that is arranged in display screen the place ahead, this array comprises a plurality of cylindrical lenss that are arranged in parallel along the axis of lens, the axle of the row of the described axis of lens and display screen forms predetermined inclination α,

Proposed to be used for the method for synthetic colored autostereoscopic image again on the other hand according to of the present invention, implemented this method and be in order to provide picture material to display device according to the present invention, this method comprises:

According to above-mentioned a plurality of (P) available digital picture, come the synthetic encoded display matrix of forming by the set of voxel, each voxel all with described image pixel in one be associated, each voxel all comprises one group of P encoded pixel, each encoded pixel is corresponding to the viewpoint that is associated with described image pixel, each encoded pixel is by respectively with first, the second and the 3rd color is associated and is arranged in three continuously three first in row and three continuation columns, the second and the 3rd coding unit is formed, make the described encoded pixel that is associated with given viewpoint aim at along the diagonal line between the unit that has been offset the plurality of continuous row and column basically, the described encoded pixel of same voxel arranges continuously that along transverse axis wherein the color in each continuous encoded pixel is recycled skew.

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Blackview P2 Lite 3D - Lo Smartphone con Display 3D. Best Discount. 27 December 2017. Archived from the original on 22 February 2020. Retrieved 4 August 2021 – via YouTube.

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Marvel Digital Limited will also be showcasing Singapore"s largest glasses free 3D screens – measuring 3.6m by 2.0m – during the Global Web 5.0 conference on 1 Nov 2022

SINGAPORE, Oct. 6, 2022 /PRNewswire/ -- Metaverse Blockchain company Coinllectibles™️, Cosmos Group Holdings Inc. (OTC: COSG), is pleased to announce that it will be partnering Marvel Digital Limited to incorporate autostereoscopic 3D technology into the Digital Ownership Tokens (DOTs) minted by the Group.

Marvel Digital Limited is an award wining technology company that has been developing autostereoscopic 3D technology since 2013. Autostereoscopic 3D technology allow users to experience 3D content from devices without the need to wear 3D glasses and Marvel Digital Limited has registered more than 60 related patents.

Gerald Gn, Corporate Finance Director of Coinllectibles, said, "Based on our market research, we believe we are one of the first blockchain companies that has Digital Ownership Tokens (DOTs) which are playable on autostereoscopic 3D devices. Not only will this give our owners another way to enjoy the DOTs, more importantly, this will differentiate us from the rest of the companies that deal with NFTs."

"In terms of implementation, we intend to do this with selected art pieces first. Our DOTs have always been positioned as an ownership token for the physical art pieces – that does not change. However, in these specially curated 3D DOTs, owners will also get digital copies of the art, that have been digitally enhanced to be playable on autostereoscopic 3D screens. In this way, through the autostereoscopic 3D devices, owners who bought those art DOTs can still get to enjoy the artwork without actually taking possession of the physical item," added Gerald.

As part of their outreach efforts, Marvel Digital Limited will be showcasing Singapore"s largest glasses-free 3D screen during the Global Web 5.0 conference on 1 Nov 2022. The screen has a viewable area of 3.6m by 2.0m and it will be the first time that the company is displaying this technology in Singapore.

On Marvel Digital Limited"s participation in the Global Web 5.0 Conference, Patrick commented, "As part of our expansion plan, we have always wanted to enter into the ASEAN markets. Other than large screens we also have technology for tablet and even phone sized devices. On top of such display hardware, we have developed processor chips that can be used to greatly enhance users" 3D experiences as well as software – such as instant 2D-to-3D conversion programs. In short, we are able to provide our partner with a full fledge 3D ecosystem and we see the Global Web 5.0 conference as an excellent platform for us to showcase our exciting technologies."

1. IntroductionNowadays, virtual reality (VR) technology has attracted a great deal of interest by virtue of its imagination, immersion, and interaction characteristics[1]. To build a virtual scene that enables people to feel almost like they are in the real world, the VR display is required to provide immersive and stereoscopic images. Previous reports on VR display are mainly about head-mounted displays (HMDs) and curved projection screens[2,3]. For HMD[4,5], the display panel is placed very close to the eyes and generates an immersive stereoscopic effect by sending stereo images to each eye from separate optical paths. The main problem for HMD is that the accommodation-convergence mismatch would become more serious than common stereoscopic television[5]. For curved projection screens[6,7], multiple projectors are usually used in pairs so as to illuminate the entire cylindrical screen, and polarizing filters are utilized to separate the left/right eye channels. So, people can receive immersive stereoscopic images by wearing polarizer glasses when they stand inside the cylinder. However, the de-polarizing effect[7] would appear at the top or bottom of the screen because of the large incident angle of projecting light, so some stereoscopic effect will be lost. Besides the mentioned problems, both HMD and curved projection screens need special eyewear, which is not suitable for people with myopia and for prolonged use[8].To solve these problems, autostereoscopy may be a good solution, which does not need any form of special glasses or other user-mounted devices[9–11]. The traditional way for autostereoscopic display is based on the parallax barrier[12,13], which is composed of vertical apertures separated by black masks. Left and right eye image columns are placed alternately on the display panel, and the parallax barrier can control light passing only to the desired zone and forming multiple discrete viewpoints. The viewpoints are strictly fixed, so people cannot freely rotate or move their heads, which leads to a non-immersive viewing experience. The low degree of freedom is the major reason why there have been few reports about autostereoscopic display for application in the VR field. In 2004, Tanaka et al. proposed an immersive autostereoscopic display named telexistence wide-angle immersive stereoscope (TWISTER)[14], which is composed of 30 display units. The display unit consists of one parallax barrier and two LED arrays, which correspond to two eyes. People can receive immersive autostereoscopic images by rotating display units around him and presenting time-varying patterns. The rotating method is inspiring; however, it would also lead to a bulky configuration, optical instability, and difficulty for image generation. Therefore, an immersive autostereoscopic display based on a static and fixed structure needs to be developed.In this Letter, we will present an immersive autostereoscopic display based on a curved screen and parallax barrier. Three consecutive pixels on the curved screen and parallax barrier make up a stereoscopic display unit. The pixels on both sides provide images for the left and right eyes, respectively, under the action of the curved parallax barrier. The middle pixel is set to be black to work as the second parallax barrier to prevent the crosstalk between the left and right images. The structure parameters and display characteristics of this proposed display system are investigated theoretically. The simulation and experimental results show that no crosstalk exists in the viewing zones. Moreover, the viewing direction can be freely rotated around the cylindrical center in this centrosymmetric display structure, so an immersive stereoscopic vision is achieved. This work provides an impetus towards the development of the autostereoscopic display in VR applications.

2. Structure and PrincipleFigure 1(a) shows the configuration of the proposed display system based on the curved screen and parallax barrier. Display pixels are connected circularly to form a curved screen. Three consecutive pixels make up a display unit: pixels “R” and “L” provide images for right and left eyes, respectively, and pixel “M” is used to prevent crosstalk. Discrete black strips are placed circularly and separated by a slit with a certain width, to obtain a curved parallax barrier. The curved screen and parallax barrier share the same center O, and the distance between them is constant, which makes the whole display structure centrosymmetric. The detailed geometrical relationship between the curved screen and parallax barrier can be described as follows: straight lines are drawn from the center O to the edges of the black strip, and the lines will intersect at the junctions between different pixels.

Figure 1.(a) Configuration of the immersive autostereoscopic display based on a curved screen and parallax barrier; (b) principle and (c) structure parameters of one display unit.Figure 1(b) shows the display unit and its working principle. A parallax barrier is arranged in front of the three pixels. Under the effect of the parallax barrier, pixels “R” and “L” form four regions. Regions I and II correspond to the viewing zones for the right and left eyes, respectively. Region III is the crosstalk zone where the pixels “R” and “L” are visible simultaneously. In contrast to that, no pixels can be seen in region IV. To prevent the crosstalk, the middle pixel “M” is set to be black to act as the second parallax barrier[12]. When the right eye is located in region I, it will see the pixels “R” and “M” through the slit at the same time. The existence of pixel “M” does not affect the image content of pixel “R” but only decreases its illuminating intensity, so the right eye can receive the right image with lower luminance. Considering that the left eye has a similar display procedure, an autostereoscopic vision can be achieved as long as the eyes stay in their corresponding regions. Moreover, since the whole structure [Fig. 1(a)] is centrosymmetric, people can watch the images by rotating around the center O, thereby an immersive autostereoscopic effect can be obtained.Figure 1(c) shows the structure parameters of the display unit. The parallax barrier with slit width ws and black strip width wb is placed in front of the display pixel with a width of wp. The distances from the center O to the slit, black strip, and pixel are denoted by rs, rb, and rp, respectively. All of these distances are represented by dotted lines. θ is the angle of the pixel relative to the center O. re represents the maximum horizontal movement distance for one eye. Beyond the allowable distance, one of the two eyes will see the wrong images. Considering that the interpupillary distance is usually about 65 mm[15], re is set to be 70 mm in this paper. From the geometrical relationships in Fig. 1(c), the following equations are obtained:wp2=rp×tan(θ/2),(1)wpre=rp−rsrs,(2)ws2=rs×tan(θ/2),(3)rb=rscos(θ/2)×cosθ,(4)wb2=rb×tanθ.(5)On the basis of these equations, we can design an immersive autostereoscopic display and simulate its display characteristics.

3. Results and DiscussionAn immersive autostereoscopic display model is developed, with the structure parameters as shown in Table 1. Considering that the angular resolution of human eye is about 1′ (0.017°), the pixel angle θ is set to be 0.016° to fulfill the viewing requirements. rp is set to be 1000 mm, which means that the viewing distance from center O to the screen is 1 m. Based on Eq. (1), wp is calculated to be 0.279 mm. Moreover, on the basis of the Eqs. (2)–(5), ws and wb are calculated to be 0.278 mm and 0.556 mm, respectively, which indicates that the aperture ratio of the parallax barrier is about 33.3%. rs and rb have the same value of 996.03 mm because θ is too small.

rb996.03As shown in Fig. 1(b), the display unit has three pixels, so the angle of the display unit relative to center O is 0.048°. When the eyes focus on the image content, the effective horizontal field of view (FOV) is about 50°[15,16], which means that there will be thousands of display units that can be received in the eyes at the same time, as shown in Fig. 2(a). To prevent the crosstalk, the viewing zone for each eye is changed to a specific shape compared to region I or II shown in Fig. 1(b). The detailed mathematical expression of this specific shape can be found elsewhere[16]. The viewing zones for the right and left eyes are repainted in Fig. 2(b), and a coordinate system is established for the convenience of the following description. The origin locates at the center O. Futher, the y axis splits the two viewing zones equally, and the x axis is perpendicular to the y axis and passes through the center O. Therefore, the viewing zones for the right and left eyes are located in the positive and negative directions, respectively, of the x axis.

Figure 2.(a) Viewing zones for numerous display units; (b) viewing zones with a coordinate system.The software LightTools is used to build up the theoretical model of the immersive autostereoscopic display and investigate its crosstalk characteristics. The structure parameters of the theoretical model are set according to Table 1. The number of light sources is 1042 in the horizontal direction corresponding to the effective horizontal FOV. A surface receiver with a size of 130mm×10mm is used to measure the illumination distribution along the x axis. To achieve the simulation results as accurately as possible, the number of tracing rays is set to 500 million. Firstly, the pixels “M” and “R” are set to be non-illuminated, where only pixel “L” is set to be illuminated, and the ray tracing simulation result is shown in Fig. 3(a). It can be seen that all the received light converges in the region on the left side of center O, which is the viewing zone for the left eye. A more intuitive and accurate light distribution result is also shown in Fig. 3(b). It can be clearly seen that the light illumination keeps zero in the region on the right side of center O, that is, there is no light from pixel “L” that can enter the viewing zone for the right eye, which shows a non-crosstalk characteristic. Further, the pixels “M” and “L” are set to be non-illuminated, and only pixel “R” is illuminated; then similar but opposite results are obtained in Figs. 3(c) and 3(d). It can be seen that there is no light from pixel “R” in the viewing zone for the left eye. The simulation results shown in Fig. 3 provide a good basis to prove that the combination of the parallax barrier and pixel “M” can effectively prevent the crosstalk between the two viewing zones, which ensures a good autostereoscopic quality.

Figure 3.Simulation results when only pixel “L” is set to be illuminated: (a) ray tracing result and (b) illumination distribution on the surface of receiver. Simulation results when only pixel “R” is set to be illuminated: (c) ray tracing result and (d) illumination distribution on the surface of receiver.Furthermore, to validate the reliability of simulation results, an experimental model of the immersive autostereoscopic display is built up, and the schematic structure is shown in Fig. 4(a). A pixels film, which is a transparent film with pixels printed on it, combined with an ambient light source is used as the curved screen. In the pixels film, pixels “R” and “M” are set to be opaque, and pixel “L” is set to be transparent. So, under the ambient light illumination, pixels “R” and “M” are non-illuminated, and pixel “L” is illuminated, which is the same as the simulation condition described above. The parallax barrier is composed of parallel, periodic opaque, and transparent parts. The pixels film and the parallax barrier film are attached to the outside and inside surface, respectively, of a piece of curved glass, so the distance between the two films and the curvature radius of the two films can be easily determined by the thickness and curvature radius of the curved glass. A camera with a horizontal FOV of 50° is used to capture the light from the pixels film. Two locations are selected for the camera, and their coordinates are (−32.5,0) and (32.5, 0), which are used to match the usual interpupillary distance.

Figure 4.(a) Schematic structure and (b) experimental setups to test the immersive autostereoscopic display based on a curved screen and parallax barrier.According to the schematic structure shown in Fig. 4(a), and the structure parameters shown in Table 1, the experimental setups are developed, as shown in Fig. 4(b). The curved glass is fabricated by the hot melt technique, and its height and thickness are 0.8 m and 4 mm, respectively. The curvature radius and the arc length of the outside surface of the curved glass are both 1 m. The pixels film and parallax barrier film are attached to the outside and inside surface of the curved glass, and the microscope images of the two films are also shown in Fig. 4(b). The horizontal lengths of the two films are both 0.9 m, so the two films can provide an effective horizontal FOV of 50° for the digital camera, which can move along the x axis.Figure 5(a) shows the image captured by the camera when located on the coordinate (−32.5, 0). It can be obtained that the scene under the ambient light can be seen, which indicates that the light from pixel “L” can enter the camera in the viewing zone for the left eye. When the camera is moved to the coordinate (32.5, 0), the image turns out to be all black, as shown in Fig. 5(b). The all black image demonstrates that no light from pixel “L” can enter the camera in the viewing zone for the right eye, which shows a non-crosstalk characteristic. Moreover, considering that the configuration of the experimental setups is bilaterally symmetric, it recognizes that a reversed result can be obtained when pixels “L” and “M” are set to be opaque, and pixel “R” is set to be transparent. The experimental results shown in Fig. 5, which have a good agreement with the simulation results shown in Fig. 3, provide further evidence to prove the effectiveness of the proposed immersive autostereoscopic display system. It should be noted that some black stripes can also be seen in the Fig. 5(a). It is a typical phenomenon in the autostereoscopic display based on parallax barrier[17], which is induced by the barriers and will cause the loss of display brightness[8]. To further decrease the effect of the parallax barrier, it can be achieved by using the slanted barrier[18] or increasing the backlight illumination[19]. We will improve this problem in our future work to get better application prospects.

4. ConclusionWe have demonstrated an immersive autostereoscopic display based on a curved screen and parallax barrier with a static and fixed structure. The display principle and structure design are investigated in detail. Three consecutive pixels and parallax barriers form a display unit. Under the action of the numerous display units, two separated viewing zones are generated for the left and right eyes. After building up a theoretical model in optical software, the simulation results show that there is no crosstalk between these two viewing zones. Moreover, the viewing direction can be freely rotated around the cylindrical center to achieve an immersive stereoscopic vision. We also build up an experimental model to test the display characteristics of this proposed display system. The results show that the left and right images can be obtained with the non-crosstalk effect, which proves the effectiveness of this display system. Therefore, we believe that this work will open a promising way to design immersive autostereoscopic displays for VR applications.

When we go to the cinema to see 3D movies, we usually wear special 3D glasses to achieve real 3D visual effects. On the contrary, 3D LED display is a kind of LED display, which allows the audience to enjoy the real 3D image with naked eyes. It is installed outdoors. Like the traditional LED display, it is usually installed on the front of the building to attract potential customers passing by to watch the 3D brand story or product details and make a deep impression.

Recently, more and more brands have foreseen the unexpected brand effect of 3D outdoor advertising LED display as a new method. For example, the Swiss watch manufacturer IWC Schaffhausen displayed the details of the 3D watch on the 3d led screen on the landmark Piccadilly light screen in central London; In Chengdu, China, a giant spacecraft broke through the 3D LED screen. Actress Rosamund Parker shot 3D content and promoted the wheel of time in Paris, New York, Madrid and Tokyo. They have attracted extensive interest and Discussion on social media. The rise of 3D LED displays has witnessed the innovative breakthrough of display technology and the refreshing visual impact. This is not only the future of advertising display, but also the breakthrough innovation of the combination of modern public art and display technology.

Autostereoscopic 3D LED display is a technology that does not require additional 3D glasses or any other tools to produce vivid led 3D performance. People can enjoy the immersive experience of spatial dimension with less visual fatigue.

Video processing: after the host outputs the information stream analog signal of the 3D movie video source, the digital DVI signal is generated. The digital signal passes through the video decoding system to output signals for the left eye and the right eye. The signal is processed by the video display module and then loaded onto the LED screen. Through the binocular parallax principle, the audience can see the 3D effect.

At present, all major cities are making naked eye 3D screens. The more famous ones are Chengdu taiguli business district, Guangzhou jiazhaoye, Chongqing Guanyin bridge, Beijing Wangfujing and so on.

All walks of life are making progress, and the display screen is no exception. It is a new breakthrough in the field of outdoor display. Interactive screens may appear in the future, and people may interact with large screens through sounds, gestures, etc.

In order to create these vivid effects, not only hardware such as LED display and control system must have excellent performance, but also corresponding 3D video production, including angles, details and a series of algorithms.

Since 3D LED display is more commercially feasible than traditional outdoor advertising display in the future, consumers and brands pay more attention to 3D display. The 3D image presented by the 3D outdoor advertising display screen is more realistic and convincing than 2D, because it has a larger area, a higher pixel density, and no edge physical elements that make the image look unreal. Therefore, with the 3D LED screen, your brand image and product display will become lifelike. In addition, 3D images bring viewers a new visual experience that 2D images do not, thus stimulating customers to spend more time exploring your brand and products. 3D technology adds depth to your content and makes your advertising more influential.

Naked eye 3D LED display is a kind of 3D effect that can be seen on the screen without wearing professional glasses. Because of its unique display mode, it also caused a sensation when it was listed. Due to the fierce market, the naked eye 3D technology quickly broke through the visual limitations of many viewpoints, and then there was no breakthrough in the naked eye 3D LED display technology. The whole industry can be said to be silent, and full-dimensional vision is still the development direction of the industry. Why not take this step? In the final analysis, its market awareness is not strong and its market capacity is limited, so it is difficult to form a corresponding industrial chain. Even if enterprises develop new products, there is no market in the industry to consume their products, leading to a waste of R & D funds and seriously hindering the enthusiasm of manufacturers in R & D. What is more fatal is that the high price of the naked eye 3D LED display screen has frightened many users. Moreover, the research and development cost of the naked eye 3D display screen is not low, and the enterprise has the research and development ability and cannot bear the risk of long-term return. Therefore, in the future, most enterprises have turned to other sub fields, making the development of naked eye 3D display industry more difficult.

In each subdivision field of LED display screen, all kinds of display screens have very clear application scene positioning. For example, the small spacing display screen is suitable for indoor application display such as conference command center; Transparent screens are suitable for outdoor advertising and glass film pasting screens, and corresponding technologies are further developed according to their clear positioning to promote a wide range of application scenarios and further promote the research and development of industrial products. But there are always exceptions. Compared with other displays, the application scene of naked eye 3D LED display is fuzzy, and the corresponding technology cannot touch the bypass, making the industry development very slow.

Although the 3D display screen is not as good as various subdivision displays in traditional applications, with the development of visual display technology, it can highlight the display mode of the naked eye 3D LED display screen and make it bright in the application of the dance stage. The unique naked eye 3D LED display mode creates a sense of spatial dimension. Combined with the stage lighting, it creates an immersive lighting and film feast, which brings a strong visual impact to the audience. In addition, in recent years, the demand for artistic performances has been rising, and the future prospect of immersive visual performance stage is very broad.

The Leyard Group is a global leader in fine pitch LED and premier supplier of visual digital signage and displays,established in 1995,main products include pine pitch LED displays series, front access LED display series,outdoor fixed led display series, rental led display series,MicroLED series, interactive conference LED display series, wholesales series, custom led screens and so on.

Shenzhen Lianjian Optoelectronics Co., Ltd. was established in 2003 and successfully listed on the Shenzhen Stock Exchange Growth Enterprise Market in 2011 with stock code 300269. It is a leading LED screen display supplier in China, providing domestic and foreign customers with mid-to-high-end LED display equipment and display. Control system development, manufacturing, engineering installation and after-sales service and other overall solutions.LianTronics is dedicated to provide professional digital media and visualization solutions for industries such as retailing,government,military,utility,transportation,education and broadcasting.The successful cases such as sports event Olympic games,World Cup and NBA,important clients like Tencent,Huawei,Alibaba and so on.

Founded in 2012, as a LED display brand of Unilumin which is focusing on channel distributions.Lamp is the world’s leading provider of large-screen digital display systems and comprehensive solutions for big data information visualization.Focus on new display panels, big data information visualization, optical electronics, image processing, signal transmission, etc. In the field of technology, it is committed to improving the visual experience of human display technology.Products mainly in HD LED screens,fixed LED screens,rental LED screens and creative LED screens.

Shenzhen Unilumin Technology Co., Ltd. was established in 2004 and listed in 2011.Unilumin supplies world-class LED screens and solutions for control room,broadcast,commercial,retail,entertainment,sports,landscape lighting and many other applications.Products mainly in commercial LED signage, rental LED signage, sports LED signage and so on.

Flinky has been specialized in LED field since 2014,a world-class manufacturer in China,aims to be your reliable LED screen partner and manufacturer.The LED displays meet international standards such as CE,RoHs,CCC,FCC,TUV,Saber,BIS,UL and so on.Providing you with 3~5 years warranty.For more information about Flinky LED display, please follow us on Twitter,Linkedin,Facebook,Instagram,Pinterest,Tumblr and so on!

Absen Group (stock code: 300389), founded in 2001, is the world’s leading provider of true LED display applications and services. Products are exported to more than 130 countries and regions in America, Europe, Australia, Asia, Africa, etc. Excellent product cases include Presidential Press Conference, China International Import Expo, World Cup, NBA game, New York Times Square, etc. So far, more than 50,000 cases have been successfully implemented. An application example, widely used in advertising display (standard billboards, outdoor large screens, transportation hubs, street view advertising, digital signage, sports, etc.), stage display (corporate events, public events, performing arts activities, TV broadcasting, etc.), commercial display (brand chains, commercial complexes, theme parks, exhibitions, churches, cruise ships, casinos, etc.), data visualization (control rooms, radio and television studios, etc.), conference screens (government and enterprises, education, finance, hotels, etc.), The export value of display products has ranked first in the industry for 12 consecutive years

Shenzhen ROE Technology Co., Ltd.was established in 2006 with a registered capital of 215.5 million. It is a provider of comprehensive solutions for “LED vision system”; it is a provider of “LED creative” integrating research, production and sales. It is a high-tech enterprise with “type display solutions”; it is a benchmark enterprise in the “LED stage display rental industry”.ROE, dubbed the “Apple” of the display industry, is a company that shares the same philosophy with Disney. They attach great importance to quality and service, and have the most high-end products in the industry, including various international industrial design awards. ROE ranks first in the LED rental display industry in terms of scale, and ranks top 1 in North America and Europe in terms of export volume. It is the preferred partner of top international leasing companies. It has offices in many overseas places, provides global services, and has great international brand influence.

The range of LED displays developed, designed and produced by InfiLED include fast and thin rental screens, smart high-definition fixed screens, multi-functional angle creative screens and high-brightness refresh stadium screens. The product application fields cover advertising, transportation, performing arts, sports, monitoring, Conducting, conference, cultural and creative industries, etc., have been exported to more than 85 countries and regions around the world. Passed CCC, CE, UL, ETL, FCC, RoHS, TUV and other certifications.

Shenzhen Ledman Optoelectronics Technology Co., Ltd. (stock abbreviation: Ledman, stock code: 300162) was established in 2004. It is the world’s leading expert in LED ultra-high-definition display, the leader in 8K ultra-high-definition LED giant screen display, and the first company in China. LED display high-tech listed company, strategic partner of China’s aerospace industry, producer of ice and snow rings for the opening ceremony of the 2022 Beijing Winter Olympics. Ledman focuses on the 8K ultra-high-definition video industry, assists the development of 5G+8K, takes the 8K Micro LED ultra-high-definition display products based on advanced COB technology as the leader, and jointly creates a full range of LED products and solution ecosystems.

Focusing on high-tech LED products, Ledman has established LEDMAN Ledman ultra-high-definition display large screen based on advanced COB technology, LEDMAN Ledman smart conference interactive large screen, LEDMAN Ledman ultra-high-definition giant screen and LED intelligent lighting, LED creative display in The whole series of LED products in the ecosystem and solution system. Under the background of today’s 5G ultra-fast coverage, Ledman keeps up with the trend of the times, starting from 5G+8K+AI, and is committed to building platforms in the fields of smart cities and data center visualization solutions.

Huang, Y.-g., Liu, W.-w.: Geometry Modeling for Autostereoscopic Display Based on Principle of Parallax Illumination. J. Liquid Crystals and Displays 21(5), 579–583 (2006)

Yang, L., Song, X.-h., Hou, C.-p., Dai, J.-f.: Image Synthesizing for Autostereoscopic Display Based on Lenticular Technology. J. Journal of Tianjin University 40(9), 1105–1110 (2007)

Son, J.-Y., Saveljev, V.V., Choi, Y.-J., et al.: Parameters for designing autostereoscopic imaging systems based on lenticular, parallax barrier and IP plates. J. Society of Photo-Optical Instrumentation Engineers 42(11), 3326–3333 (2003)

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In naked-eye LED 3D display, vernier fringe is apparent for a conventional parallax barrier. This paper presents an intended misplaced parallax barrier with discrepant width of Light Translucent Slits (LTSs) to weaken vernier fringe. Because of the wild Black Matrix (BM) of LED display, which causes apparent vernier fringe, we enlarge the width of the LTS and move the slits properly in their periods. This structure increases the periodic difference between the parallax barrier and pixel of the LED display, which can increase the brightness of the diazone of vernier fringe and make it to appear more sparsely. In this way, vernier fringe produced by those two periods is weakened at the condition that no obvious crosstalk of stereoimages is increased. The performances of simulation and experimental display prototype show that the diazone of vernier fringe is faded and obviously sparser in the naked-eye LED 3D display. As a result, vernier fringe of this display is significantly decreased and not visible for viewing.

Naked-eye 3D display technologies do not need any accessory such as stereo glasses and is currently a research hotspot in the field of display [1, 2]. Among them, the LCD-based parallax barrier naked-eye 3D display is a popular experimental scheme with simple structure, easy realization, and low cost, which has become a relatively mature product in recent years [3–7]. However, the LCD display screen is hard to be enlarged due to its low brightness, while the LED screen is suitable for large-screen display due to its high brightness, large size, and bright color [8–12]. For the traditional vertical parallax barrier design, the LTS is placed parallel to the column pixels of the display screen [13, 14]. When the eye sight captures the BM, which is the nonluminous part between adjacent subpixels, through the LTS, it will generally trigger the obvious periodic black and white gradient slits, named as vernier fringe [15–17], bringing discomfort to the viewers and seriously affecting the display effect. The use of an oblique parallax barrier can impair vernier fringe, but it will significantly increase the crosstalk of the stereoimage [18–21]. In order to reduce the discomfort brought by vernier fringe and not significantly increase crosstalk, this paper proposes a designing method of misplaced parallax barrier with nonuniform width of the LTS based on the wide characteristics of BM of the LED screen [22]. By appropriately increasing the width of the LTS of the parallax barrier and moving it during the period, the difference between the periodic structure of the parallax barrier and the pixel periodic structure of the LED screen can be increased, so as to reduce the correlation between the spectral element and the display screen [23] and further enhance the brightness of diazone in vernier fringe and make it sparse. Therefore, the proposed method can attenuate the vernier fringe without obvious introduction of crosstalk of the stereoimage.

We take the front-parallax barrier naked-eye 3D displayer based on the LED screen as an example to illustrate the inner structure and principle [24], which are shown in Figure 1. We set the spacing among adjacent pixels in the LED screen as p, the width of the LTS of the parallax barrier (parabar) as , Light Blocking Slit (LBS) width as , period as T =  + , optimal viewing distance as , and the distance between adjacent viewpoints as , according to the average human pupil distance. In terms of the triangle similarity principle, the relationship between the abovementioned parameters can be given by

In the parallax barrier naked-eye 3D display, since the pixels of the 2D displaying board are arranged in an orderly periodic matrix structure, the light of pixels interferes with the periodic parallax barrier in front of the pixel panel to form obvious vernier fringe, which makes the 3D display effect terrible to watch. Thus, in order to weaken the vernier fringe from the traditional vertical parallax barrier, this paper proposes a designing method of the parallax barrier with nonuniform width of LTS. As shown in Figure 2, the pixel spacing of the LED screen is denoted as  mm and the white disc, whose diameter equals to 1.5 mm, represents the actual luminous part of the pixel. In addition, half width of the BM is set as 0.5 mm, noted by mm, and the number of viewing point is set to . Also, the viewing distance S is defined as 4 m, and the adjacent distance of viewing points e is 65 mm.

First and foremost, three important parameters of the traditional vertical parallax barrier, LTS width, period, and distance from the parallax barrier to the LED screen, can be obtained by substituting the abovementioned parameters into equations (1)–(3):  mm,  mm, and mm. Then, keeping the period  mm unchanged, we alter the width of the LTS and move to the corresponding position in its respective period. However, there must be an upper limit and lower limit to the LTS width to ensure the effect of stereodisplay not to increase too sharply due to the mighty wide LTS and not to cause serious loss of stereoimage brightness due to excessive narrow LTS. The experiment verifies that the vernier fringe can be effectively weakened and the crosstalk has little effect when the width of the LTS is equal to the sum of the pixel spacing and the half width of the BM. The crosstalk can increase dramatically if the width of the LTS is further expanded. Besides, the width of the LTS equaling to the original width,  mm, is the minimal width which we can implement as the brightness of the stereoimage can be radically disrupted by the deteriorative vernier fringe when smaller width is applied. Thus, the upper limit of LTS width is  mm, and the lower limit is  mm.

We use ASAP software to simulate the brightness distribution of every view point for the naked-eye 3D display. Figure 3 illustrates the normalized luminance distribution in the horizontal direction at the optimum viewing distance. Figure 3(a) shows the simulation performance of the proposed misplaced parallax barrier with nonuniform LTS width, and Figure 3(b) demonstrates the corresponding performance of the conventional vertical parallax barrier.

Normalized brightness distribution curves of naked-eye 3D displays based on the parallax barrier at the optimum 3D view distance. (a) Using the proposed parallax barrier; (b) using the conventional vertical parallax barrier.

More specifically, the horizontal axis of Figure 3 represents the horizontal viewing position and the viewing position is directly opposite the center of the naked-eye 3D display when the value on horizontal axis reaches zero (0 mm). We can qualitatively measure the severity of crosstalk by the amount of the overlapped region of the normalized luminance distribution at each view point. The smaller the overlapped area is, the less the crosstalk is introduced and, thereby, the better the performance of the naked-eye 3D displayer is. Comparing Figure 3(a) with Figure 3(b), the overlapped region of the brightness curves of each view point in Figure 3(a) is slightly more than that in Figure 3(b), enhancing the crosstalk merely a little bit. But, it influences little on the visual zone and viewing effect.

To conduct the comparative experiments, a naked-eye 3D displaying prototype 1 with a misplaced parallax barrier with nonuniform width of the LTS and a naked-eye 3D display prototype 2 with a traditional vertical parallax barrier were produced. The dominant parameters are shown in Table 1. Also, Figure 4 demonstrates the image details of vernier fringe when two prototypes display the stereoimage, while Figure 4(a) implies applying the prototype 1 with a misplaced parallax barrier with nonuniform width of the LTS, whereas we adopt the traditional prototype 2 for Figure 4(b). The consequences show that the diazone of vernier fringe is light, thin, and sparse, giving rise to the desired viewing effect for prototype 1, but in Figure 4(b), it is prominent, wide, and dense.

Therefore, the experiment results verify that the proposed structure can obviously reduce the vernier fringe of the parallax barrier naked-eye 3D display and improve the stereoimaging effect. By appropriately increasing the width of the LTS of the parallax barrier and moving it to the corresponding position in its period, the difference between the periodic structure of the parallax barrier and the pixel periodic structure of the LED screen can be enlarged. Hence, the correlation between the splitter elements and the displaying screen can be lessened. Such a design method reduces the contrast ratio of the BM at the junction of adjacent viewpoints, thus promoting the brightness of the diazone in vernier fringe and making it sparse.

In this paper, in order to effectively reduce the vernier fringe of the parallax barrier naked-eye 3D display, a new designed parallax barrier is proposed, which is the misplaced parallax barrier with nonuniform width of the LTS. This parallax barrier can enhance the brightness of the diazone in vernier fringe and make it obviously fade, thin, and sparse. The simulation and experimental results prove that the proposed structure can effectively weaken vernier fringe at the condition that no obvious crosstalk of stereoimages is increased. Thus, the research has high practical value.