If you've been reading ebooks for any length of time then you've probably heard about how E-ink screens are nicer on the eyes than LCD screens. It's simply common sense that not having a light shine in your face must be better for you, and that is why E-ink Corp wants everyone to switch their reading over to devices with its screens.
But like some common sense assumptions, this one doesn't stand up to scientific scrutiny. A paper published in Ophthalmic and Physiological Optics last month reveals a fascinating study which suggests that it's the resolution more than the screen tech which has a harmful effect.
The paper discusses the results of a laboratory study. A group of 10 test participants were asked to read on either LCD or E-ink for several hours, and they were then tested through several objective methods (letter search task, reading speed, and pupillary light reflex) as well as subjectively queried about eye and general fatigue. The devices used in the test were the original iPad and the Sony PRS-600, and that is a detail which might influence the subjective questions (the iPad is bigger and heavier).
This question of the damaging effect of LCD screens is a chronic one, given the rise in tablets and smartphones as reading devices, and it is long past time that it was moved beyond subjective arguments to a discussion which includes real data.
And now we have it. The results of the study didn't show a significant difference in reading on the two types of screens, and in fact that the effect of reading on the two display types is very similar in terms of both subjective and objective measures.
The objective tests resulted in a mix data points, with some subjects scoring higher after reading on E-ink and others scoring higher after reading on LCD. The results from the visual fatigue query were fairly close, though the LCD did rate marginally higher. Even the reading speed was virtually identical. In fact, the only major difference was when the test subjects were queried about general fatigue. LCD test subjects reported a higher general fatigue level than did E-ink test subjects, but that could be due to the size and weight of the iPad.
E-ink is often described as being just like reading on paper, and that's why the scientists were surprised to discover that the results were so similar. They were also somewhat surprised because this study contradicted many of the studies listed in the bibliography. It has long been documented that reading on screens is more tiring than reading on paper, and the bibliography cites any number of papers from the past 30 years which prove this is true.
So yes, all those assumptions about reading on screens being bad for you had a basis in fact. But here's the catch: many of those older papers might not be relevant to how we read in 2012. As the authors point out in the paper, screen technology has improved a lot in the past decade, even more so in the past few years.
What if the reason this study couldn't find a difference in was that the subjects read on an iPad? Even today, that is a high quality screen. What if the subjects in those older studies were affected more by the poor quality of the tech than the tech itself?
If this pans out then it means the screen fetishists were right all along. A higher resolution screen really is better, and each step up in resolution is a boost in the user experience. It's not just marketing hype, anymore; pixels do matter.
image by Bitterjug