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International audience; Monocular augmented reality devices are used in aviation to help civilian or military pilots in their flying task. In those devices, a virtual image is projected in front of one eye on a see-through glass allowing them to see environment with both eyes. This glass is mounted on a helmet allowing users to maintain the virtual information, usually find in the primary flight display, in front of the eye. Given that the image is presented in front of only one eye, the two eyes are not stimulated in the same way and it can creates a phenomenon known as binocular rivalry. When it appeared, brain is not able to merge the two visuals information and an alternation between them can occur. This alternation appears according to visual condition and the question arises as is it relevant to choose the eye to display the image to limit binocular rivalry and guarantee a good performance in the tasks of recognition and control. The control task consists in matching a monocular item with a binocular item and the detection task consists in giving the right opening orientation of Landolt rings that can be monocular or binocular. Our study aims to compare the performances as a function of the position of the virtual image. These results are then compared to the results of several dominant eye tests to determine if one test can objectively determine on which eye the monocular information should be displayed when using a monocular see-through device.

International audience; Purpose: This study explores eyestrain and its possible impacts on learning performances and quality of experience using different apparatuses and imaging. Materials and Methods: 69 participants played a serious game simulating a job interview with a Samsung Gear VR Head Mounted Display (HMD) or a computer screen. The study was conducted according to a double-blinded protocol. Participants were randomly assigned to 3 groups: PC, HMD biocular and HMD stereoscopy (S3D). Participants played the game twice, allowing between group analyses. Eyestrain was assessed pre-and post-exposure on a chin-head rest with optometric measures. Learning traces were obtained in-game by registering response time and scores. Quality of experience was measured with questionnaires assessing Presence, Flow and Visual Comfort. Results: eyestrain was significantly higher with HMDs than PC based on Punctum Proximum of accommodation and visual acuity variables and tends to be higher with S3D. Learning was more efficient in HMDs conditions based on time for answering but the group with stereoscopy performed lower than the binocular imaging one. Quality of Experience was better based on visual discomfort with the PC condition than with HMDs. Conclusion: learning expected answers from a job interview is more efficient while using HMDs than a computer screen. However, eyestrain tends to be higher while using HMDs and S3D. The quality of experience was also negatively impacted with HMDs compared to computer screen. Not using S3D or lowering its impact should be explored to provide comfortable learning experience. 1

International audience

International audience

International audience

International audience

International audience

International audience; A dichotomy exists in the way virtual embodiments are currently studied: embodied entities are considered by conversational approaches as other selves whereas avatar approaches study them as users' hosts. Virtual reality applications such as in our case study often propose a different, in between embodiment experience. In the context of a virtual house for sale visit, this paper aims at examining the user's self-reported embodiment perception resulting from such a hybrid experience. To induce variability in this embodiment experience, we manipulated avatar representations (high versus low anthropomorphism) and frame of reference (egocentric versus exocentric). Results show the importance of the entity humanness to foster both experiences. When controlled by humanness, having a conversational experience appears uncorrelated to an avatar experience. This highlights the need to study these hybrid experiences as a combination of both approaches.

National audience; Depuis quelques années, de plus en plus de contenus stéréoscopiques sont disponibles au grand public. Si l'impression de relief est remarquable, il n'en reste pas moins que la vision artificielle stéréoscopique demeure fatigante. Une cause de cette fatigue est le conflit accommodation convergence. Dans cet article, nous proposons d'ajouter un flou dans la vision périphérique (le point de focalisation étant déterminé avec un eye-tracking) pour limiter ce conflit et donc limiter la fatigue visuelle.

International audience

International audience

Through Virtual Reality techniques, it is possible to create virtual objects entirely designed using computer programs. The greatest claimed advantage is that designers can modify virtual objects as much as they wish. When an object suits them, they can then decide to build a real object, using the virtual object as a template. But two important questions remain. The first one is “will the virtual object they see on the screen really correspond to the real object created?” In other words, the issue is whether immersive design (and especially stereoscopic vision) can create a perception of a virtual object which corresponds closely enough to the real object later created from the virtual object. The second one concerns the eyes strain. In some instances, exposure to stereoscopic immersion techniques can be lengthy, and eye strain sets in. We propose a method for reducing eye strain induced by stereoscopic vision. After reviewing sources of eye strain linked to stereoscopic vision, we will focus on one of these sources: images with high frequencies contents associated with large disparities (high level of relief). We will put forward an algorithm for removing the irritating high frequencies in high disparity zones (i.e. for virtual objects appearing far from the real screen level). We will elaborate on our testing protocol to establish that our processing reduces eye strain caused by stereoscopic vision, both objectively and subjectively. We will subsequently quantify the positive effects of our algorithm on the relief of eye strain; Les dispositifs d'immersion stéréoscopique sont très répandus et tendent à l'être de plus en plus (travail en immersion, film projeté en vision stéréoscopique, écrans auto-stéréoscopiques...). Dans certains cas, les immersions peuvent être longues et la fatigue visuelle s'installe. Nous donnons une méthode pour diminuer la fatigue visuelle liée à la vision stéréoscopique. Certaines applications demandent également une perception des formes très performante. Nous déterminons donc les paramètres améliorant cette perception et nous les quantifions. Ce mémoire de thèse est composé de deux parties : l'une consacrée à la perception des formes en immersion, l'autre traite de la diminution de la fatigue visuelle en vision stéréoscopique. Dans la première partie, nous commençons par expliquer comment nous percevons les formes en visions naturelle et artificielle. Ensuite nous exposons un protocole de test pour connaître quels paramètres peuvent influencer cette perception en immersion. Nous nous interrogeons notamment sur l'amélioration que peut apporter le fait de traquer le point de vue de l'utilisateur en vision monoscopique, ortho-stéréoscopique ou non-ortho-stéréoscopique. Nous évaluons également l'influence de la vision ortho-stéréoscopique et non-ortho-stéréoscopique sur la perception des formes Nous quantifions les différences entre tous ces modes de projections et déterminons quels paramètres sont les plus importants à respecter pour une bonne perception des formes. Dans la seconde partie, nous exposons les causes possibles de fatigue visuelle en vision stéréoscopique. Nous nous concentrons ensuite sur une de ces causes : les hautes fréquences spatiales liées à de grandes disparités. Nous avons développé plusieurs algorithmes traitant en temps réel les images stéréo pour supprimer les hautes fréquences gênantes (transformée en ondelette, box filter et programmation sur carte graphique d'une moyenne glissante) avant d'expliquer le choix de l'algorithme. Nous exposons ensuite notre protocole de test pour montrer que notre traitement diminue de façon objective et subjective la fatigue visuelle en vision ortho-stéréoscopique. Nous quantifions ensuite les améliorations apportées par notre algorithme sur cette fatigue.

International audience

National audience