“Tablets are not suited for reading over an extended period of time”; this statement is widespread. For example Scott Liu, head of the American-Taiwanese company E Ink Holdings, states that reading over an extended period of time on a Liquid Crystal display leads to increased visual fatigue. “The iPad is a fascinating multifunctional device, but not intended for hour-long reading” (stern.de). In comparison, E-ink readers, with their paper similar displays, are looked at as an adequate replacement for a book.
But is it true that the tablet is an inadequate device for reading over an extended period of time? Critical statements against the tablet as a replacement for the book are widespread but there is a lack of scientific evidence for these assumptions. For that reason, a study answering this question was implemented at the Institute for Research in Open- Distance- and eLearning (IFeL).
In a laboratory study, the participants read for several hours on either E-ink (Sony PRS-600) or LCD-Tablet (Apple iPad), where different measures of reading behaviour and visual strain were regularly (after each hour) recorded. These dependent measures included subjective (visual) fatigue, a letter search task, reading speed, oculomotor behaviour, and pupillary light reflex.
The results of the study show that reading on both display types is good and very similar in terms of both subjective and objective measures. Participants did not have more visual fatigue when reading on a tablet than when reading on an E-ink device. We concluded from this study that it is not the technology itself, but rather the image quality that is crucial for reading. The study shows that compared to the visual display units of past decades, recent electronic displays allow good and comfortable reading, even for extended time periods.
A few critical remarks still need to be made though. This laboratory study was conducted under artificial light conditions. Therefore it is unclear if an experiment under daylight conditions would lead to the same results. Another interesting question is how the sleep quality is influenced by different display technologies.
But still, the result of the study is an important novelty in reading research, and is opposed to many statements from publishers and subjective user self tests, that have stated that tablets are not appropriate for reading over a long period of time.
More information on the study is available online: http://onlinelibrary.wiley.com/doi/10.1111/j.1475-1313.2012.00928.x/abstract
Siegenthaler, E., Bochud, Y., Bergamin, P. and Wurtz, P. (2012), Reading on LCD vs e-Ink displays: effects on fatigue and visual strain. Ophthalmic and Physiological Optics, 32: 367–374. doi: 10.1111/j.1475-1313.2012.00928.x