Today we explore some more health advantages to NOVA's Downview monitor placement system. The Downview™ does more than save space and clear your desktop of clutter. It can also improve Dry Eye Syndrome. Here is an excerpt from some past studies regarding how the placement of your computer screen can have an impact a significant impact on your vision.
Lower monitor placement is advantageous from a visual standpoint. Hill and Kroemer (1986) found that the preferred declination of the line of sight for their subjects became lower as the object of view became closer. At 1 m. it averaged -24.5 degrees and at 0.5 m. –33 degrees below the Frankfurt Line in a seated position. Ripple (1952) found that accommodation (focusing at near objects) improved by over 25 percent with a downward gaze angle.
The eyes have a resting point of vergence (RPV), the distance at which the eyes converge when there is no object on which to converge. The RPV averages around 1.12 m. when looking straight ahead and comes in to about 0.87 m. when the gaze angle is lowered 30 degrees (Heuer and Owens, 1989). Viewing objects closer than the RPV has been found to contribute to eye strain; lowering the monitor allows one to work at the same viewing distance, but with reduced effort. As Krimsky (1948) observed, “when looking upwards, the eyes tend to diverge...and when they look down, the effort to converge is much easier.” Tyrell and Leibowitz (1990) found that lower gaze angles resulted in reduced headaches and eyestrain. Tsubota and Nakamori (1993) found that lower monitor placement exposed less of the eyeball to the atmosphere and reduced the rate of tear evaporation, thus reducing the risk of Dry Eye Syndrome.
A factor that may affect monitor location is the interaction between glare and monitor tilt. In many offices lowering and tilting the monitor back will result in unacceptable levels of glare. One of the few studies in support of eye-level monitor placement (Grandjean et al., 1983) did not control for glare, which was cited as a strong annoyance factor in that study and most likely contributed to the preferred settings. With this as the background, we have examined two aspects of monitor positioning: neck posture and the effect of monitor tilt about the horizontal axis.
Learn more about how computer use may be impacting your health and the benefits of NOVA's Downview™ products by visiting our Ergonomics section.