164 research outputs found

    The development of a free stereopsis test for active shutter displays

    Get PDF
    While many people enjoy S-3D, it is a well-known fact that a minority of the population is not able to perceive S-3D. These people have problems with stereopsis, or the ability of our brain to unconsciously fuse two 2D images into a single 3D percept. In clinical practice, several stereopsis tests are used to measure this deficiency. Most of these tests are expensive paper-and-pencil tests requiring trained observers. In this paper, we discuss a recently developed method to test stereopsis on active shutter glasses displays. This allows researchers in the lab or S-3D users at home to test stereopsis in a free and easy way. Furthermore, we were interested in the distribution of test scores. More specifically, we wanted to know if our test resulted in a continuous (graded stereopsis) or bipolar (stereopsis present or not) distribution. Results of a preliminary study (N = 128) showed evidence for the second

    Haptic-Enhanced Learning in Preclinical Operative Dentistry

    Get PDF
    Background: Virtual reality haptic simulators represent a new paradigm in dental education that may potentially impact the rate and efficiency of basic skill acquisition, as well as pedagogically influence the various aspects of students’ preclinical experience. However, the evidence to support their efficiency and inform their implementation is still limited. Objectives: This thesis set out to empirically examine how haptic VR simulator (Simodont¼) can enhance the preclinical dental education experience particularly in the context of operative dentistry. We specify 4 distinct research themes to explore, namely: simulator validity (face, content and predictive), human factors in 3D stereoscopic display, motor skill acquisition, and curriculum integration. Methods: Chapter 3 explores the face and content validity of Simodont¼ haptic dental simulator among a group of postgraduate dental students. Chapter 4 examines the predictive utility of Simodont¼ in predicting subsequent preclinical and clinical performance. The results indicate the potential utility of the simulator in predicting future clinical dental performance among undergraduate students. Chapter 5 investigates the role of stereopsis in dentistry from two different perspectives via two studies. Chapter 6 explores the effect of qualitatively different types of pedagogical feedback on the training, transfer and retention of basic manual dexterity dental skills. The results indicate that the acquisition and retention of basic dental motor skills in novice trainees is best optimised through a combination of instructor and visualdisplay VR-driven feedback. A pedagogical model for integration of haptic dental simulator into the dental curriculum has been proposed in Chapter 7. Conclusion: The findings from this thesis provide new insights into the utility of the haptic virtual reality simulator in undergraduate preclinical dental education. Haptic simulators have promising potential as a pedagogical tool in undergraduate dentistry that complements the existing simulation methods. Integration of haptic VR simulators into the dental curriculum has to be informed by sound pedagogical principles and mapped into specific learning objectives

    User-centered Virtual Environment Assessment And Design For Cognitive Rehabilitation Applications

    Get PDF
    Virtual environment (VE) design for cognitive rehabilitation necessitates a new methodology to ensure the validity of the resulting rehabilitation assessment. We propose that benchmarking the VE system technology utilizing a user-centered approach should precede the VE construction. Further, user performance baselines should be measured throughout testing as a control for adaptive effects that may confound the metrics chosen to evaluate the rehabilitation treatment. To support these claims we present data obtained from two modules of a user-centered head-mounted display (HMD) assessment battery, specifically resolution visual acuity and stereoacuity. Resolution visual acuity and stereoacuity assessments provide information about the image quality achieved by an HMD based upon its unique system parameters. When applying a user-centered approach, we were able to quantify limitations in the VE system components (e.g., low microdisplay resolution) and separately point to user characteristics (e.g., changes in dark focus) that may introduce error in the evaluation of VE based rehabilitation protocols. Based on these results, we provide guidelines for calibrating and benchmarking HMDs. In addition, we discuss potential extensions of the assessment to address higher level usability issues. We intend to test the proposed framework within the Human Experience Modeler (HEM), a testbed created at the University of Central Florida to evaluate technologies that may enhance cognitive rehabilitation effectiveness. Preliminary results of a feasibility pilot study conducted with a memory impaired participant showed that the HEM provides the control and repeatability needed to conduct such technology comparisons. Further, the HEM affords the opportunity to integrate new brain imaging technologies (i.e., functional Near Infrared Imaging) to evaluate brain plasticity associated with VE based cognitive rehabilitation

    Stereoscopic three-dimensional visualisation technology in anatomy learning: A meta-analysis

    Get PDF
    Objectives: The features that contribute to the apparent effectiveness of three-dimensional visualisation technology [3DVT] in teaching anatomy are largely unknown. The aim of this study was to conduct a systematic review and meta-analysis of the role of stereopsis in learning anatomy with 3DVT. Methods: The review was conducted and reported according to PRISMA Standards. Literature search of English articles was performed using EMBASE, MEDLINE, CINAHL EBSCOhost, ERIC EBSCOhost, Cochrane CENTRAL, Web of Science and Google Scholar databases until November 2019. Study selection, data extraction and study appraisal were performed independently by two authors. Articles were assessed for methodological quality using the Medical Education Research Study Quality Instrument and the Cochrane Collaboration's tool for assessing the risk of bias. For quantitative analysis, studies were grouped based on relative between-intervention differences in instructional methods and type of control conditions. Results: A total of 3934 citations were obtained of which 67 underwent a full-text review. Ultimately, 13 randomised controlled trials were included in the meta-analysis. When interactive, stereoscopic 3D models were compared to interactive, monoscopic 3D models within a single level of instructional design, for example isolating stereopsis as the only true manipulated element in the experimental design, an effect size [ES] of 0.53 (95% confidence interval [CI] 0.26-0.80; P <.00001) was found. In comparison with 2D images within multiple levels of instructional design, an effect size of 0.45 (95% CI 0.10-0.81; P <.002) was found. Stereopsis had no effect on learning when utilised with non-interactive 3D images (ES = −0.87, 95% CI −2.09-0.35; P =.16). Conclusion: Stereopsis is an important distinguishing element of 3DVT that has a significant positive effect on acquisition of anatomical knowledge when utilised within an interactive 3D environment. A distinction between stereoscopic and monoscopic 3DVT is essential to make in anatomical education and research

    A luminance-contrast-aware disparity model and applications

    Get PDF
    Binocular disparity is one of the most important depth cues used by the human visual system. Recently developed stereo-perception models allow us to successfully manipulate disparity in order to improve viewing comfort, depth discrimination as well as stereo content compression and display. Nonetheless, all existing models neglect the substantial influence of luminance on stereo perception. Our work is the first to account for the interplay of luminance contrast (magnitude/frequency) and disparity and our model predicts the human response to complex stereo-luminance images. Besides improving existing disparity-model applications (e.g., difference metrics or compression), our approach offers new possibilities, such as joint luminance contrast and disparity manipulation or the optimization of auto-stereoscopic content. We validate our results in a user study, which also reveals the advantage of considering luminance contrast and its significant impact on disparity manipulation techniques.National Science Foundation (U.S.) (CGV-1111415

    Apparent sharpness of 3D video when one eye's view is more blurry.

    Get PDF
    When the images presented to each eye differ in sharpness, the fused percept remains relatively sharp. Here, we measure this effect by showing stereoscopic videos that have been blurred for one eye, or both eyes, and psychophysically determining when they appear equally sharp. For a range of blur magnitudes, the fused percept always appeared significantly sharper than the blurrier view. From these data, we investigate to what extent discarding high spatial frequencies from just one eye's view reduces the bandwidth necessary to transmit perceptually sharp 3D content. We conclude that relatively high-resolution video transmission has the most potential benefit from this method

    TO COMPARE TNO VERSUS RANDOT TEST FOR MEASURING STEREOACUITY WHILE SCREENING AIRLINE PILOTS.

    Full text link

    Children and Virtual Reality: Emerging Possibilities and Challenges

    Get PDF
    Virtual Reality is fast becoming a reality, with estimates that over 200m headsets will have been sold by 2020, and the market value for VR hardware and software reaching well over $20bn by then. Key players in the market currently include PlayStation with PSVR, Facebook with Oculus Rift, Google Cardboard and Daydream, Mattel with Viewmaster, and many other brands investing in content production for various audiences. One of those audiences is young people and children. “Children and Virtual Reality” is a collaboration between Dubit, Turner, WEARVR and the COST (European Cooperation in Science and Technology) Action DigiLitEY. Dubit, Turner and WEARVR are companies that specialise in digital, TV and VR content, with an interest in developing best practices around VR and children. DigiLitEY is a five year (2013-2017) academic network that focuses on existing and emerging communicative technologies for young children. This includes wearable technologies, 3D printers, robots, augmented reality, toys and games and relevant aspects of the Internet of Things. This report brings together industry research into the effects of VR on 8 to 12 year olds, and ideas that arose from a COST funded Think Tank to explore what the research findings might mean for the use of VR by under 8s
    • 

    corecore