How to place the computer monitor: measurements of vertical zones of clear vision with presbyopic corrections

Abstract

The diagrams of the vertical zones of clear vision for different spectacles provide information on the ergonomic vertical position of computer monitors for clear vision with a comfortable head position. The grand mean of general purpose PALs suggests that the upper edge of the monitor should be at least approximately 15 cm below eye level at a typical viewing distance of approximately 75 cm. Higher monitor positions are possible with computer vision PALs.

The vertical monitor position for presbyopic computer users with progressive lenses: how to reach clear vision and comfortable head posture

“…The level of musculoskeletal symptoms was similar in the two groups, while participants with general-purpose progressive lenses had a higher mean head inclination by about 48, which was insignificant, however [F(1, 23) ¼ 2.233, p ¼ 0.15]. Figure 1 illustrates the principal scheme of the vertical zones of clear vision (replotted from König, Haensel, and Jaschinski 2015). For the present study, Figure 9 shows the average near point curves before and after the intervention (Days T0 and T2).…”

“…On the first day of Phase 2, the expert measured the comfortable head and gaze inclination and the vertical zone of clear vision. These tests are described in detail elsewhere (Masseida, Perske, and Jaschinski 2013a;Masseida et al 2013b;König, Haensel, and Jaschinski 2015) and are shortly summarised here.…”

“…The vertical zones of clear vision ( Figure 1) for the individual lenses were measured with the Inclined Optometer (König, Haensel, and Jaschinski 2015) when the observer assumed a comfortable head inclination (with closed eyes). Each participant received a print-out of his/her individual zone of clear vision and the optometric expert adjusted the monitor Figure 5.…”

“…Horizontally, clear vision at near is limited to a narrow central progressive zone (Sheedy 2004a(Sheedy , 2004bSheedy and Hardy 2005;Sheedy, Hardy, and Hayes 2006;Menozzi, Bergande, and Sury 2008) and vertically, clear near vision is limited to the lower part of the visual field. This vertical effect is illustrated in Figure 1 (replotted from König, Haensel, and Jaschinski 2015) where the average near point (the closest point that can be seen clearly) is plotted as a function of gaze inclination when the observer adopts a comfortable head inclination. The resulting curve is the borderline between clear and blurred vision, which means that the monitor should be rather low with comfortable head posture.…”

“…Figure 1. Average near point curve (in red) relative to eye position (at zero position) for a typical general-purpose progressive lens; data are replotted from König, Haensel, and Jaschinski (2015), where observers adopted a comfortable head inclination (tested with closed eyes). In the zone behind the curve, the monitor is seen clearly; three possible monitor positions are shown; the average table level and a typical range of comfortable gaze inclination (2 10 to 2 308) are included.…”