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Visual Immersion in the Context of Wall Displays Arnaud Prouzeau, Anastasia Bezerianos, Olivier Chapuis

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Visual Immersion in the Context of Wall Displays Arnaud Prouzeau, Anastasia Bezerianos, Olivier Chapuis Visual Immersion in the Context of Wall Displays Arnaud Prouzeau, Anastasia Bezerianos, Olivier Chapuis To cite this version: Arnaud Prouzeau, Anastasia Bezerianos, Olivier Chapuis. Visual Immersion in the Context of Wall Displays. Interactive Surfaces and Spaces Surfaces Companion Proceedings, Nov 2016, Niagara Falls, Canada. 10.1145/3009939.3009945. hal-01383587 HAL Id: hal-01383587 https://hal.archives-ouvertes.fr/hal-01383587 Submitted on 18 Oct 2016 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Visual Immersion in the Context of Wall Displays Abstract Arnaud Prouzeau Immersion is the subjective impression of being deeply LRI – Univ Paris Sud, CNRS, involved in a specific situation, and can be sensory or cog- Inria, Université Paris-Saclay F-91405 Orsay, France nitive. In this position paper, we use a basic model of visual [email protected] perception to study how ultra-high resolution wall displays can provide visual immersion. With their large size, depend- ing on the position of viewers in front of them, wall displays Anastasia Bezerianos can provide a surrounding and vivid environment. Users LRI – Univ Paris Sud, CNRS, close to the wall can have their visual field filled by the wall Inria, Université Paris-Saclay and they are able to see clearly a large amount information F-91405 Orsay, France [email protected] with a fine resolution. However, when close to the wall, vi- sual distortion due to large possible viewing angles, can affect the viewing of data. On the contrary, from far away, Olivier Chapuis distortion is no longer an issue, but the viewers’ visual field LRI – Univ Paris Sud, CNRS, is not fully contained inside the wall, and the information Inria, Université Paris-Saclay details seen are less fine. F-91405 Orsay, France [email protected] Author Keywords Immersion; wall displays; field of view; visual acuity ACM Classification Keywords H.5.2 [Information interfaces and presentation (e.g., HCI)]: Permission to make digital or hard copies of part or all of this work for personal or classroom use is granted without fee provided that copies are not made or distributed User Interfaces – Graphical user interfaces. for profit or commercial advantage and that copies bear this notice and the full citation on the first page. Copyrights for third-party components of this work must be honored. For all other uses, contact the Owner/Author. Copyright is held by the owner/author(s). Introduction ISS ’16 Companion, November 06-09, 2016, Niagara Falls, ON, Canada. Immersion is a well studied concept in psychology [7, 21], ACM 978-1-4503-4530-9/16/11. with many different definitions that refer to the subjective http://dx.doi.org/10.1145/3009939.3009945 impression of being deeply involved in a specific situation. This immersion can be sensory, related to the informa- tion transmitted to our senses (e.g., when wearing a Head- displayed in a panoramic way around the user, and is not Mounted Display HMD); or mental, related to a more cog- limited to a narrow field of view. Vivid and clear visual infor- nitive involvement (like when you read a book) [20]. HMDs mation means that users can view rich information content and CAVEs are considered to provide an almost perfect and with an appropriate display resolution. A wall-display sensory immersion, as they surround viewers with virtual in- can be both surrounding and vivid, because of its large formation. Nevertheless, in this paper we will study another size and high resolution. However, the degree of immer- kind of display that is becoming increasingly popular in data sion depends on the position of the user, and in particular analysis, and that can provide a certain level of immersion her distance from the display. At a short distance, close to due to its size: wall-displays. We focus on sensory immer- the display, information will fill the user’s visual field, and sion, as mental immersion relies more the content than on the quantity of viewed information will be both large and form. In particular we will discuss visual immersion. While of fine resolution. Farther away from the wall, the visual in- other aspects (e.g., audio, type of interaction) can affect formation and the wall will fill only part of the user’s visual sensory immersion, they are less relevant to wall displays. field, and there will be less of it that is clearly visible, due to visual acuity as we will discuss next. In the first case, the 0.5m to the screen With their large size and high resolution, wall-displays can user will be more immersed in the data than in the second, visualize a large quantity of data, compared to a traditional and thus the closer to the wall the user is, the larger the desktop [24]. Users can come up-close to the display to immersion. However, due to its large size, when viewers get details, or move farther away to get overviews. Due to are close to the display, there is an important distortion for 0.0 1.0 2.0 their scale and space in-front of them, they can furthermore shapes that are at a large angular distance [3], which can 1m to the screen accommodate several collaborating users [9, 12, 17]. But in turn deteriorate the user’s immersion. In this respect, the wall display characteristics can also provide a better sense closer to the wall the user is, the larger the distortion will be. of engagement than on a traditional desktop, and a feeling of being more immersed in the data [5]. Due to their large In this paper, we are discussing simple models that can 0.0 1.0 2.0 scale, they can give users the feeling of being surrounded help us study the immersion trade-offs created between 3m to the screen by data, as they cover a large part of their field of view [1], user position that affects the size of the visual field that is especially when viewed up-close. This feeling is reinforced covered by the display, and the quantity of information and by the fact that users can quickly explore data via small possible distortion based on this position. head movements [13]. Moreover, wall displays can provide 0.0 1.0 2.0 more intuitive and immediate relationship between the user Visual Field Figure 1: Representation of the and the data, as they allow for direct interaction with the The visual field is what a person sees instantaneously visual field (red, orange and yellow) data using touch [10], and embodied interaction through when looking straight ahead, this "image" is reflected on the for a 6x2m wall display (grey) for simple physical navigation when walking [2, 19]. retina of both eyes and then transmitted to the brain. The different distances (0.5, 1, 3 m). resolution of the retina is not uniform [23]. It is far higher in The user “in the middle” of the wall A display that surrounds users and provides vivid and clear the central part, which is called the fovea. From there the looking straight ahead. visual information, can increase visual immersion [21]. Sur- resolution drops quickly towards the border of the retina. rounding the user, implies that the visual information is The visual field is divided in 4 areas: the first one is the Area Visual Angle Visual Acuity Fovea 3◦ 100 % Perifovea 20◦ 30 % Plateau H: 60◦ and V: 40◦ 10 % P Peripheral 200◦ < 5 % d 0 20 40 60 80 visual angle difference (°) visual angle difference 0.0 0.5 1.0 1.5 2.0 2.5 3.0 Table 1: Visual angles of each area of the visual field, and their x E α distance from the center of the wall (m) visual acuity compared to that of the fovea. H stands for horizontal, Figure 3: Difference between the and V for vertical. c visual angle at the origin and the actual visual angle for an object on fovea (in red in Figure1&5), then surrounding it is the per- the wall (of width w = 1m) in ifoveal area (orange), the plateau (yellow) and finally the function of the distance x between peripheral area [16]. Table1 gives for each area the visual w = d · (tan( + n ) − tan( − n )) this object and the center of the a 2 a 2 angle [16] and the visual acuity compared to the fovea [23]. wall, for different user’s distances d d n In the following sections, for simplicity, we won’t consider h = 2 · cos(a) · tan( 2 ) to the wall: 0.5m (green), 1m (blue) and 3m (black). The user is "in the the Peripheral area as its visual acuity is low, and it lacks Figure 2: Imagine an ellipse at position (C) on the wall, with width middle" of the wall. q(x;d;w) = of color and static sensitivity. However, peripheral vision (w, size in the PC direction) and height (h, size in the direction ? w w x+ 2 x− 2 is important for noticing dynamic information on wall dis- to PC). This ellipse is seen as a circle of angular size n, when arctan( d ) − arctan( d ): plays [15]. viewed from position E, that is at distance d of the wall, with view dnx 0 m 1 m 4 m angle a.
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