NYT: Do E-Readers Cause Eye Strain?

[ggendel]

Originally Posted by DawnFalcon

Except of course eyes don't have a linear refresh rate. So that comparison is nonsense*.

*Actually, I'd use far FAR stronger terms.

Me too. I worked on a psycho-visual model of the human vision system and there are many factors that come into play but this refers to integration time not refresh-rate. It's one of the reasons that digital-TV generally puts out such bad quality video, because it takes a well-trained eye to see it. Take a look at a single frame far from an anchor (I) frame in a high motion scene. A lot of the areas around the movement is a blocky pixelated mess. It's one of the reasons that they give extra bandwidth to sporting events. Unfortunately, I've been trained to see it for my work so I have a hard time viewing today's TV.

[Demas]

That's utter bollocks, the "blocky pixelated mess" is related only compression technology not refresh time- or the choice of display technology AT ALL- and is no way analogous to human vision which has no meaningful change of bandwidth or compression (barring millions of years of evolution). Integration is WORSE with reflected light precisely because of the diffuse texture which creates "noisy" images, compared to the clean precision of emitted light requiring the eyes- and mind- resolve/integrate far less.

The inane comment of non-linear refresh would be relevant if we were talking about magnitudes at all relevant to the human nervous system.

[DawnFalcon]

Yes, of course the entire body of vision/optical science is wrong and you're right.
Wait...

For starters, it's quite clear that that Human vision is "lossy"...
Then there's the bit about light being different because it's reflected or not (when what matters is how well it matches the ambient lighting and colour balance...)

I could go on, but it's quite clear you know next to nothing about the topic.

[badbob001]

Originally Posted by Demas

Integration is WORSE with reflected light precisely because of the diffuse texture which creates "noisy" images, compared to the clean precision of emitted light requiring the eyes- and mind- resolve/integrate far less.

Are you telling me that if I look at an apple directly with my eyes and then at a video feed of the same apple, the latter is less noisy and requires less work for my brain? No wonder I tend to fall asleep in front of the TV.

[LtChambers]

Demas, can you point me to quantitative data about what near-visible EM frequencies (not just visible light, also infrared and ultraviolet) are transmitted by popular reflective (eink and paper) and emissive (CRT, LCD) technologies? Also, if there's a split up between LED and CCFL LCDs, that would be helpful. I have a hunch that LED-LCDs are less straining than CCFLs, but I haven't tested it (anecdotally) myself.

You earlier posted that "light is light". I'd like to see the numbers to back that up. My eyes get strained reading LCD much more than eink and I can't understand that if your assertion is true.

[DawnFalcon]

LtChambers - LED-lit LCD's tend to generate less eyestrain because they are capable of a greater degree (especially at the lower end) of adjustment to the brightness of their backlight, and their colour balance is often also closer to that of ambient lighting.

[LtChambers]

Also Demas, you seem to argue for taking the "long view" in many of your posts. But taking the long view, reading will become completely obsolete as cybernetics and virtual reality mature. This view is possibly longer than yours, but probably not as long as some might think. Just looking at the changes in the last 30 years, the trend toward electronic living is very strong.

[Demas]

Originally Posted by badbob001

Are you telling me that if I look at an apple directly with my eyes and then at a video feed of the same apple, the latter is less noisy and requires less work for my brain? No wonder I tend to fall asleep in front of the TV.

Depends, but in the text context, certainly textured, yellowed, [or greyed e-ink] is a much noisier image than with a good screen. In any case, refresh is a misnomer with respect to LCD (unlike CRT)... barring movement, the refresh speed itself is irrelevant compared to the GAP between light-to-light states and the way refresh occurs.

Originally Posted by LtChambers

Demas, can you point me to quantitative data about what near-visible EM frequencies (not just visible light, also infrared and ultraviolet) are transmitted by popular reflective (eink and paper) and emissive (CRT, LCD) technologies? Also, if there's a split up between LED and CCFL LCDs, that would be helpful. I have a hunch that LED-LCDs are less straining than CCFLs, but I haven't tested it (anecdotally) myself.

You earlier posted that "light is light". I'd like to see the numbers to back that up. My eyes get strained reading LCD much more than eink and I can't understand that if your assertion is true.

The reason there is no clinical study is because the technology is empirically trivial unsophisticated- and frankly- stupid, the tech outpaces the duration of a meaningful trial, and fundamentally all the experts acknowledge habit is the controlling factor.

If your eyes hurt more it is almost certainly due to poor reading habits.

Put another way, it's like asking doctors to run clinical trials on which burns the tongue more... convection heated water or microwave heated water. A scientist completely comprehends the lack of distinction between the effect of boiling hot water on human irrespective of the tech used to heat it... however, they might attribute more people getting burned by microwaved water because it doesn't always signal it's heat by bubbling the way convection heated water does. So the difference, if any, is completely explained by people chugging hot water... rather than sipping carefully.

The phenomena is completely understood.

Likewise, there's no voodoo to LCDs, they've been around for decades (longer than e-ink for that matter if you want to ascribe black magic to anything). ZERO experts advise dumping LCDs in favor of e-ink for the sake of your eyes, they ALL simply advise better viewing habits. Good habits, no worries.

[DawnFalcon]

We don't understand squat about how the eye works.

You are trying to ascribe the same sort of knowledge we have of the physical structure of H2O to something as complex as the eye. We are only now starting to understand many of the issues which are involved: but it's clear from the studies done that ambient lighting and colour balance compared to the reading medium are important.

Saying "poor reading habits" rather than looking at the fact that you might be looking at an overly bright, poorly colour-balanced CCFL-lit LCD screen as the whole cause of eyestrain...

[LtChambers]

Originally Posted by Demas

The reason there is no clinical study is because the technology is empirically trivial unsophisticated- and frankly- stupid, the tech outpaces the duration of a meaningful trial, and fundamentally all the experts acknowledge habit is the controlling factor.

The tech outpaces a trial? How long does it take to have people read for a few hours and report their eye strain? This isn't healthcare research where survival over a human's lifetime is critical to study.

If your eyes hurt more it is almost certainly due to poor reading habits.

So I have poor reading habits on LCD but not on eink or paper books? I'm supposed to change my reading habits when I read on LCD? The expert quotes I've seen say to take a break from LCD monitors every 20 minutes. This is not the case with eink and paper. I can read eink or paper for hours without eye strain. With LCD my eyes get tired within an hour, and the larger the screen the faster it happens. I tried playing Oblivion on a 32" HDTV as a PC monitor and I was worn out in 10 minutes.

The phenomena is completely understood.

Likewise, there's no voodoo to LCDs, they've been around for decades (longer than e-ink for that matter if you want to ascribe black magic to anything). ZERO experts advise dumping LCDs in favor of e-ink for the sake of your eyes, they ALL simply advise better viewing habits. Good habits, no worries.

As a computer programmer, I suppose I could resort to punch cards during my "good habit" breaks every 20 minutes of screen time. But I'd prefer a less straining display technology. Whether that technology comes in the form of less light, a different way of delivering it, or a way to induce proper blinking, I'm not sure what's best. But I know LCD isn't it because I've tried the superior alternatives. Anecdotally, anyway.

[Demas]

I can't see Dawn's post but if I had to guess, it's an inane deck-stacking comment like:

"Bright LCDs are blinding, shriek!" ignoring, completely, that bright reflective reading is detrimental too... and that good habits, preclude using stupidly bright levels of lighting for ANY display. And, undoubtedly, Dawn has not cited any authority who suggests that changing to e-ink rather than changing habits. If you search for any authority on eyestrain they will NEVER attribute it to voodoo, it will always be things like focal length, rest, blinking, etc. E-ink isn't magic.

How close am I?

btw, LtC, I missed your question between displays... LCD screens update independently of their backlights, florescent backlights use electronic ballasts and flicker at 20,000 Hz... no more onerous- if not better- than most of artificial lightning. LED backlighting uses direct current and doesn't flicker at all... in fact, better than incandescent light which you might be using to read reflectively.

[DawnFalcon]

I refer you once more to the scientific paper I linked on the issue, while you have consistently only linked popsci websites. "Good habits" cannot magically dim overly bright backlights.

[Demas]

Originally Posted by LtChambers

So I have poor reading habits on LCD but not on eink or paper books?

Undoubtedly. Get better LCD tech. Again, adjusting lighting on reflective tech is more intuitive (since that's how you see everything), but far from exclusive.

As a computer programmer, I suppose I could resort to punch cards during my "good habit" breaks every 20 minutes of screen time. But I'd prefer a less straining display technology.

20 minutes is a lowest common denominator recommendation applicable to CRTs. For quality LCDs, the time limit is 2-3 hours, which is exactly the same amount of time the AOA recommends for paper reading.

[LtChambers]

Originally Posted by Demas

btw, LtC, I missed your question between displays... LCD screens update independently of their backlights, florescent backlights use electronic ballasts and flicker at 20,000 Hz... no more onerous- if not better- than most of artificial lightning. LED backlighting uses direct current and doesn't flicker at all... in fact, better than incandescent light which you might be using to read reflectively.

I asked about near-visible light because my hunch is that CCFLs produce energy outside the visible spectrum where LEDs might not. That's where opinions are pretty useless and data is everything. And I don't know details about what happens to light when it's reflected from various surfaces (specifically eink and paper). For all I know, the flickering light source could be reflected at a constant rate.

[Demas]

Originally Posted by LtChambers

I asked about near-visible light

Again, no voodoo... if it doesn't trigger the chemical reaction in the eye, it's not relevant. To the extent that voodoo rays bug you, it's not through the eyes which are no more sensitive to "near-visible" light than any other organ in your body except to the extent that eyes are vulnerable period.

The emissions are super low and gov't safe. No voodoo.