0.75H

1.5H

Average gazing point, standard deviation and ratio of gazing point when viewing image

Images were displayed on a 55-in liquid crystal display (REGZA55X3, Toshiba, Tokyo), with 4K resolution.
Subjects could view the display from three viewing distances (0.75H [51cm], 1.5H [102cm], 3H[204cm]) and three viewing locations (Left: subject located 1/4 of the display width left of display center; Center: subject located at the display center; and Right: subject located 1/4 of the display width right of the display center). A schematic of the viewing locations (examples of 0.75H and 1.5H) is indicated on the left figure.
The distributions of gazing points were gathered in the screen center.When viewing distance approached from 3H to 0.75H, difference of the average gazing point locations among viewing locations became larger.

Analysis of gaze movement when changing viewing distance and viewing position

Apr.1 2023

The standard viewing distance for TV images is the distance at which the scan line structure cannot be seen, based on a person's eyesight. This was six times the height of the screen (denoted here as “H”) in the NTSC system TV (525 scanning lines), and 3H for current HDTV images (1125 scanning lines). Viewing angles at each position were 12° and 30°, respectively. However, advances in high-resolution pictures and practical use of 4K (4000 scanning lines) and 8K (8000 scanning lines) displays are increasing. Such displays are planned for use at the 2020 Tokyo Olympic Games. The standard viewing distance for 4K is 1.5H, and that for 8K is 0.75H; meanwhile, the viewing angles from the viewer extend 60° and 100°, respectively.We hypothesized that viewing distances and viewing locations would influence subjects’ gaze point distribution when viewing a super-high-definition image at a short distance.
　Therefore, we measure gaze movement while viewing 4K images when changing viewing distance and viewing position. In this study, viewing distance set 3 condition 0.75H (51cm: H is the display height) ,1.5H (102cm) and, 3H (204cm) and viewing position set 3 condition (Left: where 1/4 of the display width was moved left from the display center; Center: at the display center; and Right: where 1/4 of the display width was moved right from the display center). We measure gaze movement while viewing 3 images from eye movement and head movement, and analyze gazing points.
As a result, the distributions of gazing points were gathered in the screen center. Signicant difference was shown among the picture, viewing distance, or viewing position with both the 0.75H and 1.5H conditionscompared with 3H condition.

References, Hideaki Takahira, Shinya Mochiduki, Mitsuho Yamada Analysis of gaze movement when changing viewing distance and viewing position,IEICE Trans. Infromation and Systems, Vol.J99-D,No.3,pp.-,Mar. 2016 in Japanese
Shinya MOCHIDUKI, Reina WATANABE,Hideaki TAKAHIRA, Mitsuho YAMADA, Analysis of head movement during gaze movement with varied viewing distances and positions, IEICE TRANS. FUNDAMENTALS E101-A(6) 892-899 2018