The transition from CRT to LCD monitors: Effects on monitor placement and possible consequences in viewing distance and body postures

Abstract This study investigates the changes in monitor placement, caused by the transition from cathode ray tube (CRT) to liquid crystal displays (LCDs), and discusses possible effects on the resulting viewing distance and the compensating workers’ postures. The comparison between 148 workplaces equipped with CRT and 115 equipped with LCD monitors, revealed that the LCD monitors are positioned closer to the rear side of desks, augmenting the mean distance of the screen from the front edge of the desk by nearly 10 cm. The above finding suggests that the mean effective viewing distance may have also increased by the same amount. Considering data on monitors’ types, specifications and operating systems’ default character size, the study also suggests that in LCD monitors, the augmented viewing distance often exceeds the recommended angular height for comfortable reading while in a comfortable sitting posture. With the aid of a cybernetic model and the above empirical findings, we attempt to explain how the increase of the available effective space in front of the worker offered by LCD monitors may result in the adoption of adverse postures to improve the screen's legibility. Relevance to industry LCD monitors are relatively new, but rapidly spreading in the computerized offices, due to their advantages compared to the CRT monitors. Studying the possible side effects of this transition in a pragmatic manner based on data from actual work settings, may not only help to better understand the persisting adverse postures in modern LCD workplaces, but may also direct the way for practical improvements.