Viewpoint-Tolerant Depth Perception for Shared Extended Space Experience on Wall-Sized Display.

The evolution of Virtual Reality (VR) technology has contributed in all fields, including psychology. This evolution involves improvements in hardware and software allowing more immersive experiences. In a VR environment users can perceive the sensation of presence and feel immersed. These sensations are possible using VR devices as HMDs. Nowadays, the development of the HMDs has focused on improving their technical features to offer full immersion. In psychology, VR environments are research tools because they allow the use of new paradigms that are not possible to employ in a real environment. There are some applications for assessing spatial memory that use basic methods of HCI. However, VR systems that incorporate stereoscopy and physical movement have not yet been exploited in psychology. In this thesis, a novel VR system combining immersive, interactive and motion features was developed. This system was used for the assessment of the spatial memory and the evaluation of depth perception. For this system, a virtual maze task was designed and implemented. In this system, two different types of interaction were integrated: a locomotion-based interaction pedaling a fixed bicycle (condition1), and a stationary interaction using a gamepad (condition2). This system integrated two types of display systems: 1) The Oculus Rift; 2) A large stereo screen. Two studies were designed to determine the efficacy of the VR system using physical movement and immersion. The first study (N=89) assessed the spatial short term memory using the Oculus Rift and the two types of interaction The results showed that there were statistically significant differences between both conditions. The participants who performed the condition2 got better performance than participants who performed the condition1. However, there were no statistically significant differences in satisfaction and interaction scores between both conditions. The performance on the task correlated with the performance on other classical neuropsychological tests, revealing a verisimilitude between them. The second study (N=59) involved participants who had and who had not stereopsis. This study assessed the depth perception by comparing the two display systems. The participants performed the task using the condition2. The results showed that the different features of the display system did not influence the performance on the task between the participants with and without stereopsis. Statistically significant differences were found in favor of the HMD between the two conditions and between the two groups of participants regard to depth perception. The participants who did not have stereopsis and could not perceive the depth when they used other display systems (e.g. CAVE); however, they had the illusion of depth perception when they used the Oculus Rift. The study suggests that for the people who did not have stereopsis, the head tracking largely influences the 3D experience. The statistical results of both studies have proven that the VR system developed for this research is an appropriate tool to assess the spatial short-term memory and the depth perception. Therefore, the VR systems that combine full immersion, interaction and movement can be a helpful tool for the assessment of human cognitive processes as the memory. General conclusions from these studies are: 1) The VR technology and immersion provided by current HMDs are appropriate tools for psychological applications, in particular, the assessment of spatial short-term memory; 2) A VR system like the one presented in this thesis could be used as a tool to assess or train adults in skills related to spatial short-term memory; 3) The two types of interaction (condition1 and condition2) used for navigation within the virtual maze could be helpful to use with different collectives; 4) The Oculus Rift allows that the users without stereopsis can perceive the depth perception of 3D objects and have rich 3D experiences.

Many wall-size display systems are built to provide large-scale visualization. These systems may be quite successful for some limited applications, but are very inflexible, since these systems only have fixed display regions. This paper integrates steerable projectors whose beam can be moved under computer control onto a wall-size display system to strengthen its display ability. With the steerable projectors, the integrated display system, named Flexible Display, provide an extendable display region. This consists of a large-scale display region and several movable display regions, such that the integrated display system has great potential in the area of human-computer interaction and information visualization. This paper applies the Flexible Display to a virtual museum application to give the users fluent navigation experience. For the application, the Flexible Display provides the following functions: 1) intensity and resolution enhancement of sub-region of display wall, 2) information augmentation, and 3) “stepping user interfaces” for its viewers interacting with display wall.

There has been much research concerning visual depth perception in 3D stereoscopic displays and, to a lesser extent, auditory depth perception in 3D spatial sound systems. With 3D sound systems now available in a number of different forms, there is increasing interest in the integration of 3D sound systems with 3D displays. It therefore seems timely to review key concepts and results concerning depth perception in such display systems. We first present overviews of both visual and auditory depth perception, before focussing on cross-modal effects in audio-visual depth perception, which may be of direct interest to display and content designers.

Laparoscopic surgeons require extended experience of cases to overcome the lack of depth perception on a two-dimensional (2D) display. Although a three-dimensional (3D) display was reported to be useful over two decades ago, 3D systems have not been widely used. Recently, we developed a novel 3D dome-shaped display (3DD) system, CyberDome. In the present study, a total of 23 students volunteered. We evaluated the effects of the 3DD system on depth perception and laparoscopic procedures in comparison with the 2D, a conventional 3D (3DP) or the 2D high definition (HD) systems using seven tasks. The 3DD system significantly improved depth perception and laparoscopic performance compared with the 2D system in six new tasks. We further found that the 3DD system shortened the execution time and reduced the number of errors during suturing and knot tying. The 3DD system also provided more depth perception than the 3DP and 2D HD systems. The novel 3DD system is a promising tool for providing depth perception with high resolution to laparoscopic surgeons.

Virtual reality (VR) displays aim to create highly immersive virtual environments based on the principle of binocular disparity, which reproduces spatial information of virtual scenes through the fusion processing of binocular disparity by the visual system. However, due to the differences between VR displays and real‐world scenes, the challenge of rendering in VR displays in a manner that aligns with users' natural depth perception principles has not been fully addressed. In this paper, the virtual image distances (VIDs) of RGB channels in head‐mounted display (HMD) were measured and a depth perception experiment based on random dot stereograms (RDS) according to the measured VID values was designed. The depth perception comfort fusion thresholds in VR systems were determined by psychophysical methods, and the results demonstrate that the comfort fusion threshold for uncrossed disparity is significantly lower than that for crossed disparity. Additionally, user interaction performance in the determined virtual depth scenarios showed a 12.94% reduction in reaction time and a 16.86% improvement in accuracy compared to other virtual depths. Our findings provide further understanding of comfortable depth visual presentation in VR displays, which is crucial for enhancing user experience and promoting the widespread adoption of VR technology across various applications.

Mixed reality (MR) is a technique which can combine a virtual environment and a real environment without making users feel that anything is unnatural. We propose a method using a see-through head mounted display (STHMD) to improve the precision of depth perception using tactile feedback. The visual accuracy of depth perception was measured when virtual objects were displayed through a STHMD. Subjects perceived the real objects to be closer to them than the virtual objects. The reason for this may be due to the optical characteristics of the HMD. We then manipulated our fingers while watching virtual objects through the STHMD. After decreasing the visual depth gap, we measured how accurately subjects moved their fingers to the exact location where the virtual objects appeared. From the results, it was found that there were depth gaps between our fingers and the virtual objects. Finally, vibratory tactile feedback was presented to the fingertip when the finger was near the virtual object. We measured how accurately subjects moved their fingers to the virtual objects. There was a range where subjects did not perceive the gap between their fingers and the virtual objects when tactile feedback was presented. The reason for this improvement was the integration between visual and tactile information. Accordingly, by controlling the degree of perceptual error through various tactile feedback, we assume that the precision of depth perception would improve. From the above results, we have proposed that using visual and tactile integration is one method that could solve the problem of inaccurate virtual objects' depth perception.

Purpose:To compare the complication rates, surgical time and learning curve using the 3-D Heads up display system in comparison with the conventional microscope for routine cataract surgery.Methods:Consecutive consenting adults with uncomplicated cataract were offered phacoemulsification using the 3-D Heads up display system (ARTEVO 800 Carl Zeiss Meditec) or the conventional microscope (Zeiss Lumera 700) by two experienced surgeons. Surgical time, measured from start of corneal incision to removal of microscope from the surgical field and complication rates were compared between the groups.Results:Of the 343 eyes enrolled, 100 (29%) underwent surgery using the 3-D Heads up display system. The surgical time for 3-D Heads up display system was significantly higher in the 3-D group (8.4 ± 2.1 vs. 6.5 ± 1.8 minutes, P < 0.001). There were no group differences in surgical complications (2% in 3-D vs. 2.5% in conventional microscope, P = 0.28). Comparing across 4 quartiles within the 3-D group, the mean surgical time was slightly higher during the 1st quartile (n = 25, 9.1 ± 1.9 minutes) compared to the last quartile (n = 25, 8.2 ± 1.9 minutes) (p = 0.17). Complications in the 3-D group occurred only in the initial 50% of cases. Seven (7%) cases in the 3-D group were converted to conventional binocular microscope of which 3 each were due to difficulty in depth perception and low illumination while one was due to intraoperative pupillary constriction.Conclusion:Phacoemulsification with the 3-D Heads up display system takes longer time but offers excellent visualization, ergonomics and safety compared to conventional microscopes. Experienced surgeons should be able to adapt easily after their first 50 surgeries.

Intelligent interactive systems should not ignore the individuality of the user. The one-size-fits-all approach, especially in user interaction, is not appropriate when user satisfaction and acceptability is a primary goal. Each user has unique human cognitive processing styles and abilities. In addition, emotions change over time, which possibly affect the user's cognitive state and the overall interaction process. Unsurprisingly, the users' ability to control their emotions is another essential factor in adapting user interfaces, applications and data delivery. How can an interactive system adapt to human cognitive and emotional factors with the aim to deliver a personalized and more usable interface? Is there a user interface to an application or system that is equally effective to all types of users? How can we place the human in the center of every day's interaction and task activity? This keynote speech will present some approaches that our work at the DMAC Lab/SCRAT Group has addressed on how individual differences in human cognitive processing and emotional factors place the user in the center of every day interaction.

&#x0D; &#x0D; &#x0D; Driving Simulators are a valuable tool for the evaluation of driver assistance systems and analysis of user behaviour. They consist of a vehicle mock-up and a display, motion and an audio system. As, driving is mainly a visual task and the driver receives most of the information through his eyes, so the configuration of the display is very important for accurate perception of surroundings. Important features of a display system are its distance from driver's eyes, field of view, continuity and the picture quality of the displayed image. In order to simulate motion, most of the existing driving simulators consist of a dome, mounted on a Stewart platform, which is either stationary or moves on a rail or a horizontal table. Due to the limiting working space of the motion system of such driving simulators, they cannot accurately simulate longitudinal accelerations so they use scaled vehicle dynamics model or blend the longitudinal movement of simulator with the tilt movement, which the driver perceives as unrealistic motion cues. To eliminate the issues of false motion perception in the driver, a mobile driving simulator is developed, which is to be driven on a planar area and a display system is designed around it. The display system covers the horizontal and vertical field of view of the driver and the distance of the display system from the driver's eyes is chosen in such a way that it takes into account the accommodation effects, which helps in the perception of depth. This results in a display system in the form of 220º cylindrical dome with a diameter of approximately 4.8 meter.&#x0D; &#x0D; &#x0D;

Background/Aim: The three-dimensional (3D) display system can solve essential problems in conventional laparoscopic radical prostatectomy (LRP), like depth perception and spatial orientation. Several studies reported initial comparisons of LRP with 2D and 3D vision systems in terms of operative outcomes, with 3D systems coming out on top. However, there are few published comparison studies on the long-term outcomes of LRP with 2D and 3D vision systems. In this regard, we aimed to compare operative and long-term functional results of 3D-High definition (HD) LRP with conventional two-dimensional (2D)-HD display systems. Methods: A total of 115 cases that underwent LRP between October 2010 and December 2016 were prospectively evaluated, and a prospective cohort study was conducted. Inclusion criteria at baseline were as follows: age at surgery &lt;75 yr, prostate-specific antigen (PSA) concentration &lt;20 ng/ml, clinical tumor stage &lt;T4, no diagnosis of metastatic disease, and informed consent to participate in the study. Patients who underwent salvage treatments after LRP and patients with incomplete follow-up were excluded. The patients were divided into groups, Group 1 (n=72) and Group 2 (n=43), according to the display systems used, 2D-HD vs. 3D-HD during LRP. Demographic data, operative and postoperative, and long-term follow-up outcomes were recorded. Additionally, urinary continence rate determined with a patient questionnaire and erectile functions determined with the International Index of Erectile Function (IIEF) questionnaire were recorded. All obtained parameters were compared between the groups using the independent t-test and the chi-square test. Differences were considered significant at two-sided P &lt;0.05 and 95% confidence interval. Results: All patients completed a 24-month follow-up procedure. The groups were similar in age, serum PSA level, prostate volume, preoperative Gleason score, and cancer-positive core number. There were significantly better results in group 2 than in group 1 for operative parameters, catheterization time, and hospital stay (P&lt;0.001, for all parameters). At long-term follow-up, the urinary continence rate was significantly higher in group 2 than in group 1 (P=0.023). Similarly, significantly higher IIEF scores were determined in the group 2 (P&lt;0.001). Conclusion: Our results suggest that using a 3D-HD display system during LRP provides much better long-term functional and operative outcomes and may provide a cheap and equal alternative to the RARP procedure.

We address human factors and technology issues for the design of stereoscopic display systems that are natural and comfortable to view. Our title "just enough reality" hints at the contrast between the popularly perceived requirements for strict "virtual reality" and the expert's pragmatic acceptance of "sufficient reality" to satisfy the human interface requirements of real-world applications. We first review how numerous perceptions and illusions of depth can be exploited to synergistically complement binocular stereopsis. Then we report the results of our experimental studies of stereoscopy with very small interocular separations and correspondingly small on-screen disparities, which we call "microstereopsis." We outline the implications of microstereopsis for the design of future stereoscopic camera and display systems, especially the possibility of achieving zone-less autostereoscopic displays. We describe a possible class of implementations based on a nonlambertian filter element, and a particular implementation that would use an electronically switched louver filter to realize it.

With the development of the information industry, the wearable three‐dimensional (3D) near‐eye display that can provide complete visual information has attracted increasing attention. Compared with other existing 3D display technologies, the holographic display is a promising true 3D display technology that can fully record and reproduce the original 3D scenes. The ability to present a continuous parallax and depth perception gives holography technology an unprecedented promise in the next‐generation 3D near‐eye display. However, currently available holographic near‐eye display systems can only provide a limited viewing area (including the field of view and eyebox), greatly restricting its practical application. Focusing on the development requirements of large viewing‐area 3D holographic near‐eye display, the reasons are introduced first why the viewing area of current holographic displays is limited and then the existing solutions from different aspects, including multiplexing‐based methods, steering viewing window methods, aperiodic wavefront modulation methods, and some emerging holographic display technologies are summarized. These various solutions are analyzed respectively, and their representative works are investigated. In addition, the different applications of holography in the near‐eye display system are also discussed. Finally, the advantages and disadvantages of these techniques are compared and perspectives are given.

Collaborative View Configurations for Multi-user Interaction with a Wall-size Display.

Bishop Berkeley suggested that the distance of an object can be estimated if the object’s size is familiar to the observer. It has been suggested that humans can perceive the distance of the object by using such “familiarity” information, but most or many of the prior experiments that found an effect of familiarity were not designed to minimize or eliminate potential influences of: higher cognitive factors on the observers’ responses, or the influences of low-level image features in the visual stimuli used. We looked for the familiarity effect in two experiments conducted both in Russia and Japan. The visual stimuli used were images of three coins used in Russia and Japan. The participants’ depth perception was measured with a multiple-choice task testing the perceived depth-order of the coins. Our expectation was that any effect of “familiarity” on depth perception would only be observed with the coins of the participant’s country. We expected a substantial familiarity effect based on our meta-analysis of the “familiarity” effects observed in prior experiments. But, our results in both experiments showed that the familiarity effect was virtually zero. These findings suggest that the importance of a familiarity effect in depth perception should be reconsidered.

Motion parallax was described as a cue to depth over 300 years ago and as producing apparent motion over 150 years ago. In recent years, experimental interest in motion parallax has increased, following there discovery of the idea of yoking stimulus motion to head movement. Contemporary research indicates how depth and motion perception are dependent on the conditions of stimulation. From what we know about motion parallax, we suggest an experimental 3-D display system.