Effects of VDT Viewing Angle on User Biomechanics,Comfort,and Preference

Abstract

A study was conducted to characterize effects of computer monitor viewing angle on operators. The study was conducted in two phases: controlled laboratory experiment followed by field verification. Lab results are discussed here. Three viewing angles were studied: 0, -17.5, and -35 deg to center of screen. Effects of monitor size and keyboard familiarity were also investigated. Muscle activity, body posture, visual acuity, performance, discomfort, and preference data were collected. In general, muscle activity was greater at -35 deg than at 0 deg; and greater for a smaller monitor than a larger one. Only head postures were affected by viewing angle. The eye-ear line was angled higher for touch typists. Mousing performance slowed slightly at 0 deg. Subjects preferred the -17.5 deg angle most and the -35 deg angle least. Results suggest there could be benefits to using a larger monitor with viewing angle between -17.5 to 0 deg for screen-intensive work.

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