Article

The Effects of Visual Display Distance on Eye Accommodation, Head Posture, and Vision and Neck Symptoms

Ergonomics Program, University of California Berkeley, 1301 South 46th St., Bldg. 163, Richmond, CA 94804, USA.
Human Factors The Journal of the Human Factors and Ergonomics Society (Impact Factor: 1.69). 11/2007; 49(5):830-8. DOI: 10.1518/001872007X230208
Source: PubMed

ABSTRACT

Determine the effects of display viewing distance on both the visual and musculoskeletal systems while the text height is held constant across viewing distances.
The distance from the eyes to a computer display may affect visual and neck comfort. If the angular size of the characters remains the same, it is recommended that the display be placed at a farther viewing distance (e.g., 70-100 cm). However, in common usage, the character sizes are not adjusted based on viewing distance.
Participants under the age of 35 years (N = 24) performed visually demanding tasks using a computer display for 2 hr each at three viewing distances (mean: 52.4, 73.0, and 85.3 cm) while torso and head posture were tracked. At the end of each task, eye accommodation was measured and symptoms were recorded.
The near distance was associated with significantly less blurred vision, less dry or irritated eyes, less headache, and improved convergence recovery when compared with the middle and far distances. Participants moved their torsos and heads closer to the monitor at the far distance.
If the computer screen character sizes are close to the limits of visual acuity, it is recommended that the computer monitor be positioned between the near (52 cm) and middle (73 cm) distance from the eyes.
The location of a computer display should take into account the size of the characters on the screen and the visual acuity of the user.

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Available from: David Rempel, May 02, 2014
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    • "Figure 20shows the experimental setup. The distance between the display and the participant's face was set between 50 and 70 cm according to the most ergonomic view[27]. As shown in Fig. 21, the operators use their pupils to operate the sheath manipulator, moving the image center point from " point 0 " to " point 3 " or " point 4 " , which were displayed on a chessboard with a 25 × 25 mm 2 lattice . "

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    • "Other studies have shown that most users prefer viewing distances from 63cm to 85cm (Grandjean et al., 1983; Hennings and Ye, 1996; Jaschinski et al., 1998; Rempel et al., 2007). Compared with desktop, laptop and tablet computers, previous studies have reported that users had to lean forward and adopted decreased viewing distances when using smaller-sized computers (Shin and Hegde, 2010; Szeto and Lee, 2002). "
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    • "The subject of inquiry of this study is to outline health effects of visual–musculoskeletal interactions that may arise during strenuous near work and to provide testable hypotheses for future research. Professional use of modern instruments of Information or Communication Technology (ICT) is linked with eye–neck/scapular area problems (Treaster et al. 2006; Rempel et al. 2007; Wiholm et al. 2007; Helland et al. 2008; Torii et al. 2008; Ukai and Howarth 2008; Tornqvist et al. 2009). Understanding the causes of these lingering work–environment problems remains a major scientific goal (Lie and Watten 1987; Franzén et al. 2000; Piccoli 2003; Sjøgaard et al. 2006; Mathiassen 2006; Strøm et al. 2009). "
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