This PDF file contains the front matter associated with SPIE Proceedings Volume 9391 including the Title Page, Copyright information, Table of Contents, Introduction, Authors, and Conference Committee listing.

We propose the effective viewing window enhancement method for a holographic display with an amplitude-only SLM by using algorithmic approach. The basic concept is the superposition principle of holography. The multiple computer generated holograms (CGH) can be displayed on the SLM, and multiple 3D images are reconstructed at different positions within a viewing window simultaneously. In the experiments, we have implemented the holographic display using an amplitude-only SLM, a field lens, and laser light sources. We can observe the holographic 3D image in the frustum formed by the field lens through the viewing window located in the Fourier plane of the hologram. To enhance the effective viewing window, we generate multiple CGHs with an observer’s eye positions, and then overlap them to make the final CGH. Multiple 3D images can be reconstructed in different positions within the theoretical viewing window from the CGH displayed on SLM. This makes the enlargement of viewing zone that can observe the holographic images. The multiple holograms can be also made for enlargement of the viewing window along both horizontal and vertical direction (2D enlargement viewing zone). We confirmed that the experimental results and the simulation based on Rayleigh-Sommerfeld theory match well.

The Three-Dimensional (3D) vision became widely known as familiar imaging technique now. The 3D display has been put into practical use in various fields, such as entertainment and medical fields. Development of 3D display technology will play an important role in a wide range of fields. There are various ways to the method of displaying 3D image. There is one of the methods that showing 3D image method to use the ray reproduction and we focused on it. This method needs many viewpoint images when achieve a full-parallax because this method display different viewpoint image depending on the viewpoint. We proposed to reduce wasteful rays by limiting projector’s ray emitted to around only viewer using a spinning mirror, and to increase effectiveness of display device to achieve a full-parallax 3D display. We propose a method by using a tracking viewer’s eye, a high-speed projector, a rotating mirror that tracking viewer (a spinning mirror), a concave mirror array having the different vertical slope arranged circumferentially (a concave mirror array), a cylindrical mirror. About proposed method in simulation, we confirmed the scanning range and the locus of the movement in the horizontal direction of the ray. In addition, we confirmed the switching of the viewpoints and convergence performance in the vertical direction of rays. Therefore, we confirmed that it is possible to realize a full-parallax.

Most UHDTV content is presently created using single large CMOS sensor cameras as opposed to 2/3-inch small sensor cameras, which is the standard for HD content. The consequence is a technical incompatibility that does not only affect the lenses and accessories of these cameras, but also the content creation process in 2D and 3D. While UHDTV is generally acclaimed for its superior image quality, the large sensors have introduced new constraints in the filming process. The camera sizes and lens dimensions have also introduced new obstacles for their use in 3D UHDTV production. The recent availability of UHDTV broadcast cameras with traditional 2/3-inch sensors can improve the transition towards UHDTV content creation.

The following article will evaluate differences between the large-sensor UHDTV cameras and the 2/3-inch 3 CMOS solution and address 3D-specific considerations, such as possible artifacts like chromatic aberration and diffraction, which can occur when mixing HD and UHD equipment. The article will further present a workflow with solutions for shooting 3D UHDTV content on the basis of the Grass Valley LDX4K compact camera, which is the first available UHDTV camera with 2/3-inch UHDTV broadcast technology.

A three-dimensional (3D) capture system based on integral imaging with an enhanced viewing zone by using a camera array was developed. The viewing angle of the 3D image can be enlarged depending on the number of cameras consisting of the camera array. The 3D image was captured by using seven high-definition cameras, and converted to be displayed by using a 3D display system with a 4K LCD panel, and it was confirmed that the viewing angle of the 3D image can be enlarged by a factor of 2.5 compared with that of a single camera.

Live-action stereoscopic feature films are, for the most part, produced using a costly post-production process to convert planar cinematography into stereo-pair images and are only occasionally shot stereoscopically using bulky dual-cameras that are adaptations of the Ramsdell rig. The stereoscopic lens design described here might very well encourage more live-action image capture because it uses standard digital cinema cameras and workflow to save time and money.

There is pressing need for 3D imaging technology in many areas. A number of light field camera designs are proposed using single image sensor. However, due to the limited size of image sensor chip and optical design, the disparity of the light field captured using single sensor camera systems is very small. Stanford group pioneered an implementation of light field capture systems using camera array. But, since the camera array often employs discrete imaging sensors and associated optics, the coverage image area for 3D reconstruction is limited. We propose a novel optical design approach that customizes the design for each optical channel to maximize the image quality, coverage area, among other design targets. We then integrate the optical design of all imaging channels into a single monolithic piece with compact structure, high reliability and assembly precision. As a result, the captured light field images from all imaging channels have the same object size with uniform image quality, thus greatly improve the quality of 3D light field reconstruction.

A real-time viewpoint image generation method is achieved. Video communications with a high sense of reality are needed to make natural connections between users at different places. One of the key technologies to achieve a sense of high reality is image generation corresponding to an individual user's viewpoint. However, generating viewpoint images requires advanced image processing, which is usually too heavy to use for real-time and low-latency purposes. In this paper we propose a real-time viewpoint image generation method using simple blending of multiple camera images taken at equal horizontal intervals and convergence obtained by using approximate information of an object's depth. An image generated from the nearest camera images is visually perceived as an intermediate viewpoint image due to the visual effect of depth-fused 3D (DFD). If the viewpoint is not on the line of the camera array, a viewpoint image could be generated by region splitting. We made a prototype viewpoint image generation system and achieved real-time full-frame operation for stereo HD videos. The users can see their individual viewpoint image for left-and-right and back-and-forth movement toward the screen. Our algorithm is very simple and promising as a means for achieving video communication with high reality.

Amblyopia is a common condition affecting 2% of all children and traditional treatment consists of either wearing a patch or penalisation. We have developed a treatment using stereo technology, not to provide a 3D image but to allow dichoptic stimulation. This involves presenting an image with the same background to both eyes but with features of interest removed from the image presented to the normal eye with the aim to preferentially stimulated visual development in the amblyopic, or lazy, eye. Our system, called I-BiT can use either a game or a video (DVD) source as input. Pilot studies show that this treatment is effective with short treatment times and has proceeded to randomised controlled clinical trial. The early indications are that the treatment has a high degree of acceptability and corresponding good compliance.

This paper continues my 2014 February IS and T/SPIE Convention exploration into the relationship of stereoscopic vision and consciousness (90141F-1). It was proposed then that by using stereoscopic imaging people may consciously experience, or see, what they are viewing and thereby help make them more aware of the way their brains manage and interpret visual information. Environmental imaging was suggested as a way to accomplish this. This paper is the result of further investigation, research, and follow-up imaging. A show of images, that is a result of this research, allows viewers to experience for themselves the effects of stereoscopy on consciousness. Creating dye-infused aluminum prints while employing ChromaDepth® 3D glasses, I hope to not only raise awareness of visual processing but also explore the differences and similarities between the artist and scientist―art increases right brain spatial consciousness, not only empirical thinking, while furthering the viewer’s cognizance of the process of seeing. The artist must abandon preconceptions and expectations, despite what the evidence and experience may indicate in order to see what is happening in his work and to allow it to develop in ways he/she could never anticipate. This process is then revealed to the viewer in a show of work. It is in the experiencing, not just from the thinking, where insight is achieved. Directing the viewer’s awareness during the experience using stereoscopic imaging allows for further understanding of the brain’s function in the visual process. A cognitive transformation occurs, the preverbal “left/right brain shift,” in order for viewers to “see” the space. Using what we know from recent brain research, these images will draw from certain parts of the brain when viewed in two dimensions and different ones when viewed stereoscopically, a shift, if one is looking for it, which is quite noticeable. People who have experienced these images in the context of examining their own visual process have been startled by the effect they have on how they perceive the world around them. For instance, when viewing the mountains on a trip to Montana, one woman exclaimed, ”I could no longer see just mountains, but also so many amazing colors and shapes”―she could see beyond her preconceptions of mountains to realize more of the beauty that was really there, not just the objects she “thought” to be there.

The awareness gained from experiencing the artist’s perspective will help with creative thinking in particular and overall research in general. Perceiving the space in these works, completely removing the picture-plane by use of the 3D glasses, making a conscious connection between the feeling and visual content, and thus gaining a deeper appreciation of the visual process will all contribute to understanding how our thinking, our left-brain domination, gets in the way of our seeing what is right in front of us. We fool ourselves with concept and memory―experiencing these prints may help some come a little closer to reality.

Visual search is a task that is carried out in a number of important security and health related scenarios (e.g., X-ray baggage screening, radiography). With recent and ongoing developments in the technology available to present images to observers in stereoscopic depth, there has been increasing interest in assessing whether depth information can be used in complex search tasks to improve search performance. Here we outline the methodology that we developed, along with both software and hardware information, in order to assess visual search performance in complex, overlapping stimuli that also contained depth information. In doing so, our goal is to foster further research along these lines in the future. We also provide an overview with initial results of the experiments that we have conducted involving participants searching stimuli that contain overlapping objects presented on different depth planes to one another. Thus far, we have found that depth information does improve the speed (but not accuracy) of search, but only when the stimuli are highly complex and contain a significant degree of overlap. Depth information may therefore aid real-world search tasks that involve the examination of complex, overlapping stimuli.

With the recent introduction of Ostendo’s Quantum Photonic Imager (QPI) display technology, a very small pixel pitch, emissive display with high brightness and low power consumption became available. We used QPI’s to create a high performance light field display tiles with a very small form factor. Using 8 of these QPI light field displays tiled in a 4x2 array we created a tiled full parallax light field display. Each individual light field display tile combines custom designed micro lens array layers with monochrome green QPIs. Each of the light field display tiles can address 1000 x 800 pixels placed under an array of 20 x 16 lenslets with 500 μm diameters. The light field display tiles are placed with small gaps to create a tiled display of approximately 46 mm (W) x 17 mm (H) x 2 mm (D) in mechanical dimensions. The prototype tiled full parallax light field display demonstrates small form factor, high resolution and focus cues.

We propose a load-balancing multi-LCD light field display technology. The multiple LCD panels operate as a spatial light modulator. Each light ray is the combination of pixels located in multiple LCD panels. The challenging problem is how to decompose the light field into limited layer images and display the light field compressively. Each pixel, as a controllable unit, is in spatial-multiplexing which means one pixel needs to be responsible to modulate multiple target light rays at the same time. We analyze the load imposed on each pixel by casting the light field decomposition as an over-determined equation problem. We found each pixel works in the state of overload and single pixel couldn’t give consideration to all target light rays. In order to reduce the load on pixels and improve display fidelity, we develop a multi-layer and multi-zone joint optimization strategy. The target light field is divided into multiple subzones and each subzone is displayed by multiple LCD panels combining with a dynamic directional backlight. By resolving the target light field, our display system further explores the multi-LCD’s capability of displaying light field and higher quality of light field display is achieved. We test our load-balancing decomposition algorithm based on different scene. The parallax, occlusion and blur of out-of-focus are restored successfully. And a three-layer prototype is constructed to demonstrate that correct light field is displayed in indoor lighting environment.

We introduce our light field display simulation software that simulates the image observed by a viewer looking at a full parallax light field display. The simulation software uses the display parameters, viewer location and orientation, viewer pupil size and focus location to simulate the image observed by the viewer. This software has been used in simulating full parallax light field displays of various geometry and complexities as well as image processing and full parallax light field compression algorithms. The simulation results follow the real world observations very closely.

Effective integration of 3D acquisition, reconstruction (modeling) and display technologies into a seamless systems provides augmented experience of visualizing and analyzing real objects and scenes with realistic 3D sensation. Applications can be found in medical imaging, gaming, virtual or augmented reality and hybrid simulations. Although 3D acquisition, reconstruction, and display technologies have gained significant momentum in recent years, there seems a lack of attention on synergistically combining these components into a “end-to-end” 3D visualization system. We designed, built and tested an integrated 3D visualization system that is able to capture in real-time 3D light-field images, perform 3D reconstruction to build 3D model of the objects, and display the 3D model on a large autostereoscopic screen. In this article, we will present our system architecture and component designs, hardware/software implementations, and experimental results. We will elaborate on our recent progress on sparse camera array light-field 3D acquisition, real-time dense 3D reconstruction, and autostereoscopic multi-view 3D display. A prototype is finally presented with test results to illustrate the effectiveness of our proposed integrated 3D visualization system.

We aim to produce a wide field-of view large autostereoscopic display for multiple viewers based on a 1D retroreflective screen and overheard microprojectors. The 1D retroreflective screen consists of retroreflector, anisotropic diffuser, and embedded fiber-optic array with optical sensors. Microprojectors modified with wide angle converter lenses are mounted unobtrusively over each viewing location. Each projector’s structured lighting is detected by the screen’s sensor array for calibration. Pin-cushion distortion correction, rectification and cross-talk reduction are implemented for proper stereo fusion. We examine common viewing scenarios of single viewer autostereoscopic projection, multiprojector automultiscopic projection, side by side multiviewer common and independent autostereoscopic projection, and frontback autostereoscopic projection.

We devised dual side transparent 3D display using transparent OLED panel and two lenticular arrays. The OLED panel is sandwiched between two parallel confocal lenticular arrays, forming Gabor super-lens. The display provides dual side stereoscopic 3D imaging and floating image of the object, placed behind it. The floating image can be superimposed with the displayed 3D image. The displayed autostereoscopic 3D images are composed of 4 views, each with resolution 64x90 pix.

We proposed the 360-degree 3D display system which is composed of a flat panel display, a light control film, and holographic optical element (HOE). The HOE is a diffraction grating which is made by holography technique. HOE lens can be produced on the thin polygonal glass plate. The light control film and HOE lenses are used to control the direction of light from the flat panel display in our system. The size of proposed system depends on the size of the flat panel display is because other parts of proposed system are thin and placed on the screen of the flat panel display. HOE lenses and a light control film are used to control lights from multiple pixels of a flat panel display to multiple viewpoints. To display large 3D images and to increase viewpoints, we divided parallax images into striped images and distributed them on the display for multiple viewpoints. Therefore, observers can see the large 3D image around the system. To verify the effectiveness of the proposed system, we made the experimental system. To verify the effectiveness of the proposed system, we constructed the part of the proposed system. The experimental system is composed of the liquid crystal display (LCD), prototype HOE lenses, and light control films. We confirmed that experimental system can display two images to different viewpoints. This paper describes the configuration of the proposed system, and also describes the experimental result.

Stereo vision is a resource-intensive process. Nevertheless, it has evolved in many animals including mammals, birds, amphibians and insects. It must therefore convey significant fitness benefits. It is often assumed that the main benefit is improved accuracy of depth judgments, but camouflage breaking may be as important, particularly in predatory animals. In humans, for the last 150 years, stereo vision has been turned to a new use: helping us reproduce visual reality for artistic purposes. By recreating the different views of a scene seen by the two eyes, stereo achieves unprecedented levels of realism. However, it also has some unexpected effects on viewer experience. The disruption of established mechanisms for interpreting pictures may be one reason why some viewers find stereoscopic content disturbing. Stereo vision also has uses in ophthalmology. Clinical stereoacuity tests are used in the management of conditions such as strabismus and amblyopia as well as vision screening. Stereoacuity can reveal the effectiveness of therapy and even predict long-term outcomes post surgery. Yet current clinical stereo tests fall far short of the accuracy and precision achievable in the lab. At Newcastle University, we are exploiting the recent availability of autostereo 3D tablet computers to design a clinical stereotest app in the form of a game suitable for young children. Our goal is to enable quick, accurate and precise stereoacuity measures which will enable clinicians to obtain better outcomes for children with visual disorders.

While 3D displays are entering hospitals, no study to-date has explored the impact of binocular disparity and 3D inclination on contrast sensitivity function (CSF) of humans. However, knowledge of the CSF is crucial to properly calibrate medical, especially diagnostic, displays. This study examined the impact of two parameters on the CSF: (1) the depth plane position (0 mm or 171 mm behind the display plane, respectively DP:0 or DP:171), and (2) the 3D inclination (0° or 45° around the horizontal axis of the considered DP), each of these for seven spatial frequencies ranging from 0.4 to 10 cycles per degree (cpd). The stimuli were computer-generated stereoscopic images of a vertically oriented 2D Gabor patch with a given frequency. They were displayed on a 24” full HD stereoscopic display using a patterned retarder. Nine human observers assessed the CSF in a 3-down 1-up staircase experiment. Medians of the measured contrast sensitivities and results of Friedman tests suggest that the 2D CSF as modeled by Barten¹ still holds when a 3D display is used as a 2D visualization system (DP:0). However, the 3D CSF measured at DP:171 was found different from the 2D CSF at frequencies below 1 cpd and above 10 cpd.

This study proposes a new objective metric for video quality assessment. It predicts the impact of technical quality parameters relevant to visual discomfort on human perception. The proposed metric is based on a 3-level color scale: (1) Green - not annoying, (2) Orange - annoying but acceptable, (3) Red - not acceptable. Therefore, each color category reflects viewers' judgment based on stimulus acceptability and induced visual annoyance. The boundary between the “Green" and “Orange" categories defines the visual annoyance threshold, while the boundary between the “Orange" and “Red" categories defines the acceptability threshold. Once the technical quality parameters are measured, they are compared to perceptual thresholds. Such comparison allows estimating the quality of the 3D video sequence. Besides, the proposed metric is adjustable to service or production requirements by changing the percentage of acceptability and/or visual annoyance. The performance of the metric is evaluated in a subjective experiment that uses three stereoscopic scenes. Five view asymmetries with four degradation levels were introduced into initial test content. The results demonstrate high correlations between subjective scores and objective predictions for all view asymmetries.

This paper describes an experiment that focuses on disparity changes in emotional scenes of stereoscopic (3D) images, in which an examination of the effects on pleasant and arousal was carried out by adding binocular disparity to 2D images that evoke specific emotions, and applying disparity modification based on the disparity analysis of prominent 3D movies. From the results of the experiment, it was found that pleasant and arousal was increased by expanding 3D space to a certain level. In addition, pleasant gradually decreased and arousal gradually increased by expansion of 3D space above a certain level.

While heuristics have evolved over decades for the capture and display of conventional 2D film, it is not clear these always apply well to stereoscopic 3D (S3D) film. Further, while there has been considerable recent research on viewer comfort in S3D media, little attention has been paid to audience preferences for filming parameters in S3D. Here we evaluate viewers’ preferences for moving S3D film content in a theatre setting. Specifically we examine preferences for combinations of camera motion (speed and direction) and stereoscopic depth (IA). The amount of IA had no impact on clip preferences regardless of the direction or speed of camera movement. However, preferences were influenced by camera speed, but only in the in-depth condition where viewers preferred faster motion. Given that previous research shows that slower speeds are more comfortable for viewing S3D content, our results show that viewing preferences cannot be predicted simply from measures of comfort. Instead, it is clear that viewer response to S3D film is complex and that film parameters selected to enhance comfort may in some instances produce less appealing content.

In this paper, we investigate two error issues in stereo images, which may produce visual fatigue. When two cameras are used to produce 3D video sequences, vertical misalignment can be a problem. Although this problem may not occur in professionally produced 3D programs, it is still a major issue in many low-cost 3D programs. Recently, efforts have been made to produce 3D video programs using smart phones or tablets, which may present the vertical alignment problem. Also, in 2D-3D conversion techniques, the simulated frame may have blur effects, which can also introduce visual fatigue in 3D programs. In this paper, to investigate the relationship between these two errors (vertical misalignment and blurring in one image), we performed a subjective test using simulated 3D video sequences that include stereo video sequences with various vertical misalignments and blurring in a stereo image. We present some analyses along with objective models to predict the degree of visual fatigue from vertical misalignment and blurring.

In recent years, three-dimensional (3D) displays become more and more popular in many fields. Although they can provide better viewing experience, they cause extra problems, e.g., visual fatigue. Subjective or objective methods are usually used in discrete viewing processes to evaluate visual fatigue. However, little research combines subjective indicators and objective ones in an entirely continuous viewing process. In this paper, we propose a method to evaluate real-time visual fatigue both subjectively and objectively. Subjects watch stereo contents on a polarized 3D display continuously. Visual Reaction Time (VRT), Critical Flicker Frequency (CFF), Punctum Maximum Accommodation (PMA) and subjective scores of visual fatigue are collected before and after viewing. During the viewing process, the subjects rate the visual fatigue whenever it changes, without breaking the viewing process. At the same time, the blink frequency (BF) and percentage of eye closure (PERCLOS) of each subject is recorded for comparison to a previous research. The results show that the subjective visual fatigue and PERCLOS increase with time and they are greater in a continuous process than a discrete one. The BF increased with time during the continuous viewing process. Besides, the visual fatigue also induced significant changes of VRT, CFF and PMA.

Three dimensional (3D) displays have witnessed rapid progress in recent years because of its highly realistic sensation and sense of presence to humanist users. However, the comfort issues of 3D display are often reported and thus restrict its wide applications. In order to study the objective evaluation indicators associated with 3D visual fatigue, an experiment is designed in which subjects are required to accomplish a task realized with random dot stereogram (RDS). The aim of designing the task is to induce 3D visual fatigue of subjects and exclude the impacts of monocular depth cues. The visual acuity, critical flicker frequency (CFF), reaction time and correct rate of subjects during the experiment are recorded and analyzed. Correlation of the experimental data with the subjective evaluation scores is studied to find which indicator is closely related to 3D visual fatigue. Analysis of the experimental data shows that the trends of the correct rate are in line with the result of subjective evaluation.

This paper presents a new multi-view stereo image synthesis using binocular symmetric hole filling. In autostereoscopic displays, multi-view synthesis is needed to provide multiple perspectives of the same scene, as viewed from multiple viewing positions. In the warped image at a distant virtual viewpoint, it is difficult to generate visually plausible multi-view stereo images in multi-view synthesis since very large hole regions (i.e., disoccluded regions) could be induced. Also, binocular asymmetry between the synthesized left-eye and right-eye images is one of the critical factors, which leads to a visual discomfort in stereoscopic viewing. In this paper, we maintain the binocular symmetry using the already filled regions in an adjacent view. The proposed method introduces a binocular symmetric hole filling based on the global optimization for binocular symmetry in the synthesized multi-view stereo images. The experimental results showed that the proposed method outperformed those of the existing methods.

Full parallax light field displays require high pixel density and huge amounts of data. Compression is a necessary tool used by 3D display systems to cope with the high bandwidth requirements. One of the formats adopted by MPEG for 3D video coding standards is the use of multiple views with associated depth maps. Depth maps enable the coding of a reduced number of views, and are used by compression and synthesis software to reconstruct the light field. However, most of the developed coding and synthesis tools target linearly arranged cameras with small baselines. Here we propose to use the 3D video coding format for full parallax light field coding. We introduce a view selection method inspired by plenoptic sampling followed by transform-based view coding and view synthesis prediction to code residual views. We determine the minimal requirements for view sub-sampling and present the rate-distortion performance of our proposal. We also compare our method with established video compression techniques, such as H.264/AVC, H.264/MVC, and the new 3D video coding algorithm, 3DV-ATM. Our results show that our method not only has an improved rate-distortion performance, it also preserves the structure of the perceived light fields better.

Conventionally there exist two major methods to create mosaics in 3D videos. One is to duplicate the area of mosaics from the image of one viewpoint (the left view or the right view) to that of the other viewpoint. This method, which is not capable of expressing depth, cannot give viewers a natural perception in 3D. The other method is to create the mosaics separately in the left view and the right view. With this method the depth is expressed in the area of mosaics, but 3D perception is not natural enough. To overcome these problems, we propose a method to create mosaics by using a disparity map. In the proposed method the mosaic of the image from one viewpoint is made with the conventional method, while the mosaic of the image from the other viewpoint is made based on the data of the disparity map so that the mosaic patterns of the two images can give proper depth perception to the viewer. We confirm that the proposed mosaic pattern using a disparity map gives more natural depth perception of the viewer by subjective experiments using a static image and two videos.

Layered light field display, which consists of a backlight and several light attenuating layers, has been attracting attentions because of its potential to simultaneously support many viewing directions and high resolution for each direction. The transmittances of the layers’ pixels can be controlled individually, and are determined inversely from expected observation for each viewing direction. The expected observations are typically represented as a set of multi-view images. We have developed a simulator of the layered light field display using computer graphics technology, and evaluated the quality of displayed images (output quality) using real multi-view images as input. An important finding from the evaluation is that aliasing artifacts are occasionally observed from the directions without input images. To prevent aliasing artifacts, it is necessary to limit the disparities between neighboring input images into ±1 pixel according to plenoptic sampling theory, which requires significantly small viewpoint intervals. However, it is not always possible to capture such dense multi-view images that would satisfy the aliasing-free condition. To tackle this problem, we propose to use image based rendering techniques for synthesizing sufficiently dense virtual multi-view images from actually photographed images. We demonstrate that by using our method, high quality visualization without aliasing artifacts is possible even when the photographed multi-view images are sparse.

The common architecture of multi-view autostereoscopic displays assigns a nominal viewing distance. The design affects the convergence of the visible rays at a nominal viewing distance where diamond shaped viewing zones are created. In contrast to this approach, the authors present a new design strategy departing from the geometric relations of common 3D display designs. They show that a beam emitted from a sub-pixel should be rendered with an individual camera direction determined by an algorithm. This algorithm also uses, besides the parameters of the display design, the desired viewing distance and the allowed increments of the camera angle. This enables very flexible designs of autostereoscopic displays. The main difference from the common multiview display is that its design approach enables a continued viewing zone without the usually diamond shaped sweet spots. The algorithm for controlling the rendering and the multiplexing is generic, as well as for integral and multiview design approaches using an image splitter raster. The paper introduces it for autostereoscopic displays with horizontal parallax.

We propose a compact multi-projection system based on integral floating method with waveguide projection. Waveguide projection can reduce the projection distance by multiple folding of optical path inside the waveguide. The proposed system is composed of a wedge prism, which is used as a waveguide, multiple projection-units, and an anisotropic screen made of floating lens combined with a vertical diffuser. As the projected image propagates through the wedge prism, it is reflected at the surfaces of prism by total internal reflections, and the final view image is created by the floating lens at the viewpoints. The position of view point is decided by the lens equation, and the interval of view point is calculated by the magnification of collimating lens and interval of projection-units. We believe that the proposed method can be useful for implementing a large-scale autostereoscopic 3D system with high quality of 3D images using projection optics. In addition, the reduced volume of the system will alleviate the restriction of installment condition, and will widen the applications of a multi-projection 3D display.

The quality of the integral 3D images created by a 3D imaging system was improved by combining multiple LCDs to utilize a greater number of pixels than that possible with one LCD. A prototype of the display device was constructed by using four HD LCDs. An integral photography (IP) image displayed by the prototype is four times larger than that reconstructed by a single display. The pixel pitch of the HD display used is 55.5 μm, and the number of elemental lenses is 212 horizontally and 119 vertically. The 3D image pixel count is 25,228, and the viewing angle is 28^°. Since this method is extensible, it is possible to display an integral 3D image of higher quality by increasing the number of LCDs. Using this integral 3D display structure makes it possible to make the whole device thinner than a projector-based display system. It is therefore expected to be applied to the home television in the future.

A super multi-view display provides smooth motion parallax without special glasses, and it is expected that the observer is free from the visual fatigue caused by the accommodation-vergence conflict. However, a huge number of pixels are required on a display device because high-density rays are required for good quality images and each ray needs corresponding pixel. We have proposed a method to reduce the required number of pixels by limiting rays emitted to only around observer’s pupils. The display is based on the lenticular method. As stated above, the rays should be shot out to only around observer’s pupils. To do this, the lenticular lens of which viewing zone angle is narrowed is used and the lenticular lens is illuminated by directional light to suppress side lobes. The direction of directional light is changed to follow the observer’s pupil. In this paper, we constructed a prototype display and conducted an experiment. The experimental result confirmed that we could see image corresponding from each viewpoint by the change of the photographing images. In addition, it confirmed suppression of the side lobes by couldn’t see the image outside the viewing zone. By these results, we showed the effectiveness of the proposed method.

A novel 360-degree integral-floating display based on the real object is proposed. The general procedure of the display system is similar with conventional 360-degree integral-floating displays. Unlike previously presented 360-degree displays, the proposed system displays the 3D image generated from the real object in 360-degree viewing zone. In order to display real object in 360-degree viewing zone, multiple depth camera have been utilized to acquire the depth information around the object. Then, the 3D point cloud representations of the real object are reconstructed according to the acquired depth information. By using a special point cloud registration method, the multiple virtual 3D point cloud representations captured by each depth camera are combined as single synthetic 3D point cloud model, and the elemental image arrays are generated for the newly synthesized 3D point cloud model from the given anamorphic optic system’s angular step. The theory has been verified experimentally, and it shows that the proposed 360-degree integral-floating display can be an excellent way to display real object in the 360-degree viewing zone.

In this paper, we propose a new method that makes multi-layer images from a few viewpoint images to display a 3D image by the autostereoscopic display that has multiple display screens in the depth direction. We iterate simple “Shift and Subtraction” processes to make each layer image alternately. The image made in accordance with depth map like a volume slicing by gradations is used as the initial solution of iteration process. Through the experiments using the prototype stacked two LCDs, we confirmed that it was enough to make multi-layer images from three viewpoint images to display a 3D image. Limiting the number of viewpoint images, the viewing area that allows stereoscopic view becomes narrow. To broaden the viewing area, we track the head motion of the viewer and update screen images in real time so that the viewer can maintain correct stereoscopic view within +/- 20 degrees area. In addition, we render pseudo multiple viewpoint images using depth map, then we can generate motion parallax at the same time.

The present study aimed to examine the effect of the vision training, which is a benefit of watching 3D video images (3D video shooting game in this study), focusing on its accommodative facility and vergence facility. Both facilities, which are the scales used to measure human visual performance, are very important factors for man in leading comfortable and easy life. This study was conducted on 30 participants in their 20s through 30s (19 males and 11 females at 24.53 ± 2.94 years), who can watch 3D video images and play 3D game. Their accommodative and vergence facility were measured before and after they watched 2D and 3D game.

It turned out that their accommodative facility improved after they played both 2D and 3D games and more improved right after they played 3D game than 2D game. Likewise, their vergence facility was proved to improve after they played both 2D and 3D games and more improved soon after they played 3D game than 2D game. In addition, it was demonstrated that their accommodative facility improved to greater extent than their vergence facility. While studies have been so far conducted on the adverse effects of 3D contents, from the perspective of human factor, on the imbalance of visual accommodation and convergence, the present study is expected to broaden the applicable scope of 3D contents by utilizing the visual benefit of 3D contents for vision training.

This study contained two experimental examinations of the cognitive activities such as visual attention and memory in viewing stereoscopic (3D) images. For this study, partially converted 3D images were used with binocular parallax added to a specific region of the image. In Experiment 1, change blindness was used as a presented stimulus. The visual attention and impact on memory were investigated by measuring the response time to accomplish the given task. In the change blindness task, an 80 ms blank was intersected between the original and altered images, and the two images were presented alternatingly for 240 ms each. Subjects were asked to temporarily memorize the two switching images and to compare them, visually recognizing the difference between the two. The stimuli for four conditions (2D, 3D, Partially converted 3D, distracted partially converted 3D) were randomly displayed for 20 subjects. The results of Experiment 1 showed that partially converted 3D images tend to attract visual attention and are prone to remain in viewer’s memory in the area where moderate negative parallax has been added.

In order to examine the impact of a dynamic binocular disparity on partially converted 3D images, an evaluation experiment was conducted that applied learning, distraction, and recognition tasks for 33 subjects. The learning task involved memorizing the location of cells in a 5 × 5 matrix pattern using two different colors. Two cells were positioned with alternating colors, and one of the gray cells was moved up, down, left, or right by one cell width. Experimental conditions was set as a partially converted 3D condition in which a gray cell moved diagonally for a certain period of time with a dynamic binocular disparity added, a 3D condition in which binocular disparity was added to all gray cells, and a 2D condition. The correct response rates for recognition of each task after the distraction task were compared. The results of Experiment 2 showed that the correct response rate in the partial 3D condition was significantly higher with the recognition task than in the other conditions. These results showed that partially converted 3D images tended to have a visual attraction and affect viewer’s memory.

We have been developing an autostereoscopic display with directional backlight using Fresnel lens array. The system was originally composed of a dot matrix light source and a convex lens array and a LCD panel. We have previously proposed the methods to achieve uniform brightness and to expand the viewing zone free from crosstalk. The way to achieve uniform brightness is to add a vertical diffuser between the convex lens array and the LCD panel. The way to expand the viewing zone free from the crosstalk is to attach a large aperture convex lens onto the surface of the convex lens array. However, there still is a drawback that the viewing angle with homogenized brightness is narrow due to the darker peripheral part of the display region than the central part. In this paper two methods to enhance the viewing angle with homogenized brightness are proposed. The first one is to place two mirror boards on the upper end and the lower end between the convex lens array and the LCD panel horizontally. The second one is to place the large aperture convex lens just behind the LCD panel. By the first method, it is expected to reflect the directional light vertically and to make the upper and the lower part of the display region brighter, which enhances the viewing angle vertically. By the second method, it is expected that the directional light from the light source can be utilized more efficiently, which enhances the viewing angle horizontally and vertically.

Integral imaging (InIm) is an interesting research area in the three-dimensional (3-D) display technology. While it is simple in structure, it shows full color and full parallax 3-D images without the necessity of special glasses. InIm display usually uses the simplest lens array, and hence displayed 3-D image suffers from distortions. A dominating distortion is a Petzval curvature. To the authors' best knowledge, we have firstly analyzed an effect of the Petzval curvature in InIm display. The immediate consequence of Petzval curvature is that the depth plane of InIm display becomes a curved plane array. Using simulation, the effect of Petzval curvature is found to reduce the depth range, change the viewing direction, and increase the black stripe. The result indicates that the lens array in the InIm display should be customized to reduce these undesirable effects.

Streaming application of multi-view and free-viewpoint video is potentially attractive but due to the limitation of bandwidth, transmitting all multi-view video in high resolution may not be feasible. Our goal is to propose a new streaming data format that can be adapted to the limited bandwidth and capable of free-viewpoint video streaming using multi-view video plus depth (MVD). Given a requested free-viewpoint, we use the two closest views and corresponding depth maps to perform free-viewpoint video synthesis. We propose a new data format that consists of all views and corresponding depth maps in a lowered resolution, and the two closest views to the requested viewpoint in the high resolution. When the requested viewpoint changes, the two closest viewpoints will change, but one or both of views are transmitted only in the low resolution during the delay time. Therefore, the resolution compensation is required. In this paper, we investigated several cases where one or both of the views are transmitted only in the low resolution. We proposed adequate view synthesis method for multi resolution multi-view video plus depth. Experimental results show that our framework achieves view synthesis quality close to high resolution multi-view video plus depth.

The use of stereoscopic 3D vision affects how interactive entertainment has to be developed as well as how it is experienced by the audience. The large amount of possibly impacting factors and variety as well as a certain subtlety of measured effects on user experience make it difficult to grasp the overall potential of using S3D vision. In a comprehensive approach, we (a) present a development framework which summarizes possible variables in display technology, content creation and human factors, and (b) list a scheme of S3D user experience effects concerning initial fascination, emotions, performance, and behavior as well as negative feelings of discomfort and complexity. As a major contribution we propose a qualitative formalization which derives dependencies between development factors and user effects. The argumentation is based on several previously published user studies. We further show how to apply this formula to identify possible opportunities and threats in content creation as well as how to pursue future steps for a possible quantification.

Recently, there are tremendous growths in the area of 3D stereoscopic visualization. The 3D stereoscopic visualization technology has been used in a growing number of consumer products such as the 3D televisions and the 3D glasses for gaming systems. This technology refers to the idea that human brain develops depth of perception by retrieving information from the two eyes. Our brain combines the left and right images on the retinas and extracts depth information. Therefore, viewing two video images taken at slightly distance apart as shown in Figure 1 can create illusion of depth [8]. Proponents of this technology argue that the stereo view of 3D visualization increases user immersion and performance as more information is gained through the 3D vision as compare to the 2D view. However, it is still uncertain if additional information gained from the 3D stereoscopic visualization can actually improve user performance in real world situations such as in the case of teleoperation.

Multiview autostereoscopic displays have several image artifacts which prevent widespread adoption. Crosstalk between adjacent views is often severe, stereo inversion occurs at some head positions, and legacy 2-view content is difficult to display correctly. We introduce a method for driving multiview displays, dynamically assigning views to hardware display zones, based on potentially multiple observer's current head positions. Rather than using a static one-to-one mapping of views to zones, the mapping is updated in real time, with some views replicated on multiple zones, and some zones left blank. Quantitative and visual evaluation demonstrates that this method substantially reduces crosstalk.