Originally Posted by Gazoobee
Just as I've always maintained (and been criticised for saying here a few times), there is really no evidence that "eye strain" is caused by reading from a screen as opposed to paper, or that ePaper is any easier on the eyes than an LCD. It's basically a popular misconception.
It's not a popular misconception, I can feel it on my eyes. I don't need bad science to tell me what reading experience kills my eyes. After only a short time on a screen, I have trouble focusing into distance, and I get head aches. The same does not happen with paper, provided it's decent paper. Further, these studies always come out when relevant products show up. Researchers are paid, funded, and they want to get publicity. A study like this is perfect for the purpose, and if you phrase the research topic narrow enough, then you can come up with results that seemingly support almost any premade conclusion.
It's obviously not the fact that the display is active (i.e. a light source) that is the problem, because photons don't carry a label telling the eye that they bounced off of something or come directly from an emitter.
There are IMNSHO mainly THREE factors at work, some of which is being conveniently neglected:
1) screen flicker
2) ambient lighting
1) LCD screens are being refreshed, both the display and the backlighting flicker. While perceptually we don't notice that, this doesn't mean that on a low level it doesn't affect our eyes. Our physical bodies react to many things that don't penetrate all the way up to our consciousness, and to neglect these things is rather shortsighted (pun intended).
2) a passive reading surface requires a proper amount of ambient light. If you stare at a bright screen against a dark surrounding, your eye will strain, because it will have trouble adjusting the iris to a proper setting. The light sensitive areas that are responsible for eye adjustment take average light readings, while for proper adjustment in such a setting you'd need a spot meter, to use photography parlance. Thus a passive screen forces you to have proper lighting (unless you start using one of these clip-on book lights and read in total darkness...) An active display allows you to read in almost any lighting condition, regardless how good or bad for the eyes.
3) Apple has become so focused on what sells, that the short-term eye-poping-high-contrast effect of glossy screens has become more important to them than ergonomics, which in a time long ago was one of Apple's strengths. For Computer displays, there would even be a solution: optical coating of the smooth surface screens, like on camera lenses. That would combine the benefits of a glossy screen with massive reduction in glare. Unfortunately, that doesn't come for free, and hence Apple doesn't do it, not even as an option.
Further, for laptops, vendors like Toshiba have long offered transreflective LCD screens as an high-end option. The result is these screens can be used in bright sunlight, when Mac users are force to go packing. The only drawback is a reduction in color fidelity, but that's a minor issue on laptops that people want to use while on the go. (If you need color fidelity, you can have a second screen at home/office).
Unfortunately, optical coating isn't an option on a touch device, because finger prints would render the coating ineffective. Transreflective screens might be too thick for Apple's obsession with thin, to be used in an iPad.
In short, the iPad is pretty much unusable as a serious reading device. It's yet another consumer gadget for the typical US household that has a library with about five books in it. For some casual browsing in Cosmopolitan or Sports Illustrated, watching some You Tube, etc. it may be fine. For anyone who wants either a high-quality e-book reader or a highly mobile computing device, the iPad just doesn't cut it. For the former, the display is not going to be pleasant on the eyes for long stretches of reading, for the latter, the closed nature of the device that won't give the user full access to the hardware they own, is an absolute anathema.
For me, the iPad has only two potential uses:
a) introducing my 80 year old parents to the internet in a device that doesn't require them to learn everything that goes along with a regular computer
b) as a electronic picture frame to bring my photo shoots to clients and demo them, without having to give out copies that could be stolen before they are paid for.
There is obviously some use for the device in vertical markets, since corporations seem to have long ago stopped caring if their data is held hostage or who could get access to the data on the device.