
Backlit e-readers 'damage sleep and health' - dansingerman
http://www.bbc.co.uk/news/health-30574260
======
HackinOut
The well accepted definition of an e-reader is _" a mobile electronic device
that is designed primarily for the purpose of reading"_ (from wikipedia) and
most (all?) of those devices are reflective as opposed to LCDs which are
backlit.

 _" They spent five days reading from a paperback and five days from an
iPad."_. If only iPads were used, I don't believe the word e-reader is
appropriate.

If you use an e-ink display without a built-in light, there are no reason this
would be any different then using a book (as mentioned in the article but it's
not only about _" the original kindle"_). Also there were tons of studies
about the effect of light on sleep and especially blue light emitted by LCDs,
most e-reader makers use a warmer light if I'm not mistaken.

EDIT: elaborating

~~~
eloisant
There are a lot of e-book reader with a built-in backlight that can be turned
on and off, like the Kindle Paperwhite.

But I agree that using iPads then calling that "a backlit e-reader" is pretty
stupid. That's a tablet.

~~~
davedx
> There are a lot of e-book reader with a built-in backlight that can be
> turned on and off, like the Kindle Paperwhite.

"Paperwhite guides light toward the surface of the display with its built-in
front light—unlike back-lit tablets that shine in your eyes" [1]

I have a Kindle Paperwhite, and was surprised to read this article, because I
have no trouble sleeping. Apparently the way the light works is the reason for
this :)

[1] [http://www.amazon.com/Kindle-Paperwhite-
Ereader/dp/B00AWH595...](http://www.amazon.com/Kindle-Paperwhite-
Ereader/dp/B00AWH595M)

~~~
HackinOut
Thanks for the reference. I am not sure that backlights are the problem
though. Just imagine shining a light behind the page of a book (although it's
hardly comparable to the level of transparency of Liquid crystals). I would
rather bet on the color of the light (warm vs cold). Maybe it's all in my head
but when it's sleep time, I hate cold bulbs (and LCDs) while I am not bothered
by warm light like a candle or a warm bulb.

Furthermore, it seems to me that with the Paper White's light guided _" on the
surface of the display"_, the light shines as much in towards your eyes as it
does towards the screen...

------
paulannesley
Probably the only useful line in the article:

> The light emitted by most e-readers is shining directly into the eyes of the
> reader, whereas from a printed book or the original Kindle, the reader is
> only exposed to reflected light from the pages of the book.

So it's talking entirely about brightly backlit tablets, not e-readers with
e-ink.

~~~
hollerith
Since 2012, Amazon's high-end Kindles (the 2012 Paperwhite, the 2013
Paperwhite and the 2014 Voyage) shine light directly into the eyes. It looks
just like a backlit display although technically the light and the diffusion
panel are in front of an opaque (e-ink) display, not in back of a translucent
(LC) display. On my Paperwhite, it is impossible to turn this light off --
only to dim it.

Also, I dispute the OP's contention that reflected light on s paper book is
any better; certainly, a normal bed-side lamp is _worse_ for the sleep of
anyone sharing the room with the reader.

EDIT. Although like I just said, an iPad probably has less of a deleterious
effect on sleep than a Kindle Paperwhite does, it is probably possible to do
better in the current market. Specifically, Samsung makes a tablet (the Tab S,
which comes in 10.5- and 8.4-inch versions) with an OLED display, which has
the advantage over LCD displays that the portions of the screen that are
supposed to be black do not emit any light at all. Especially if used with
software that displays red or orange text on a black background (to minimize
the blue-ish photons) an OLED display is the best choice in the current
smartphone-plus-tablet market AFAICT if protection of sleep is the main
consideration.

EDIT. Oops, I forgot to include my main reason for preferring the iPad to the
Paperwhite: on iOS, Settings > Accessibility > Invert Colors reverses black
and white. Combined with the fact that many iOS apps like Safari and iBooks
normally present a white field broken only by text and thin lines, the use of
"Invert colors" probably results in less light entering the eye than a
Paperwhite since (unless they changed it since I last updated the software on
my Paperwithe a couple of months ago) you cannot alter the Paperwhite's
default color scheme of black text on a white background. I will concede that
the Paperwhite's brightness setting goes a lot dimmer than the iPad's does,
but I consider that consideration to be trumped by what I just wrote, and,
again, neither Paperwhite nor iPad comes close IMHO to an OLED display used
with decent software.

~~~
Ironballs
The Paperwhite isn't a backlit display.

The LEDs in the Paperwhite Kindles do not shine light directly in the eyes:
the leds shine from below the screen towards the top end of the screen. As it
exits the LEDs, light is reflected inside a light guide from which it exits
towards the display from specific holes, much like a leaky fiberoptic
cable[1].

The directionality and position of the LEDs, and the existence of the light
guide, are _precisely_ the differences which make the Paperwhite unlike a
backlit display.

[1]
[http://www.nytimes.com/interactive/2012/12/26/technology/lig...](http://www.nytimes.com/interactive/2012/12/26/technology/light-
reading.html)

~~~
ce4
That's the same with smartphones and tablets.

For the sake of simplicity and to keep it as thin as possible, they use edge-
LED lighting with a diffusor layer to spread the light evenly.

~~~
DrStalker
Are there any smartphones/tablets that have the light hit the display surface
from the front and then bounce off like the kindle does? I thought they all
either used a backlight shining through the display from behind or were an
array of tiny little light sources (depending on the screen technology used) -
either way the light is being broadcast direct from the source to your eyes;
not hitting a surface and emitting diffuse light out.

~~~
seba_dos1
Old monochrome reflective LCDs used that, but smartphones and tablets are
almost always using transmitive screens with backlight (sometimes
transflective, like on Nokia N900, but reflective properties are only usable
in very bright sunlight).

Kindle Paperwhite however has 100% reflective e-ink screen plus set of LCDs
that shine through the light guide layer above the screen. Some people think
that makes it better than transmissive LCDs - that's why using Kindle
Paperwhite instead of iPad in this test would be much more insightful, as
sleep-disturbing properties of transmissive, blue-tinted LCDs are nothing that
wasn't known before.

------
Malician
F.lux has this study on their webpage.

[https://justgetflux.com/research.html](https://justgetflux.com/research.html)
[http://www.pnas.org/content/early/2014/12/18/1418490112.full...](http://www.pnas.org/content/early/2014/12/18/1418490112.full.pdf+html)

I was really hoping for research comparing F.lux to a non-backlit screen; this
seems to tell us what we already knew.

~~~
mng2
The journal article says that they even set the brightness of the "LE-eBook"
(iPad) to maximum.

I guess we'll have to wait for more detailed studies.

------
mrob
This is one reason why I use a European model Samsung Galaxy S3 (GT-I9300) for
ebooks. It includes "mDNIe" which gives you very flexible OLED display
configuration on rooted phones. You can completely turn off the blue channel
and remap blue to green so blue things remain visible. I use the "Galactic
Night" app for switching between mDNIe modes.

To further reduce light exposure I use gray (remapped to yellow) text on a
black background (very dark because the display is OLED). I set the screen
brightness to maximum in FBReader to avoid PWM flicker, and reduce the text
brightness to compensate. I also disable the phone indicator LEDs. I don't
find reading like this to harm my sleep.

The one problem is that the mDNIe mode very briefly flashes to default when
the phone is first turned on from standby. I think this could be fixed with a
kernel patch but I just avoid looking at the screen then.

------
audunw
I put a red filter over our nightlight, which seems to work quite well for
reading paper books (or non-lit e-readers). Now I've also ordered some amber
LED bulbs, without any blue light at all, which should be a more of a
permanent solution.

I also ordered an amber filter for my phone, although I think perhaps a better
solution would be to not use phones/tablets in bed.. but I'm not sure it's
realistic to always avoid the temptation.

The final part of the solution is to have a wake-up light. I had one before,
and it's really quite essential up here in the north. But I think it would be
beneficial everywhere. Studies showed that people have different times it's
natural for them to wake up ("A" and "B" people), and if you wake up earlier
than what's natural for you, it affects your performance. Solution? Block out
all external light from the bedroom, and use a wake-up light as an artificial
sunrise. (Or allow people to come to work/school at different times, but
that's not always an option).

------
dansingerman
The study only seemed to compare An iPad with print books. While I am sure
many people who do use an iPad for ebooks I am sure there are many more Kindle
readers, which may well have given a different result.

~~~
taurath
Thats the primary reason I would buy a kindle over an iPad. Its not comparing
e-readers and books, its comparing a bright screen with books.

~~~
Nemo157
The Kindle Paperwhite has a very blue tinted light. I'm not sure about other
lighted eBooks, but I dislike that they specifically called out light emitting
vs reflective surfaces. As far as I'm aware the colour of the light makes a
much bigger difference to melatonin production than the source of the light.

EDIT: Looking at the actual paper they were definitely aware of this with
measurements of the colour spectrums of different tablets, unfortunately not
including the Paperwhite. Disappointing journalism skewing the story as
normal.

~~~
taurath
Does it now?? Is there an option to go into standard e-ink/nonlighted mode?
I've been considering purchasing one for a while in order to help my eyes at
night.

------
jonah
We just need f.lux[1] for our tablets.

[1] [https://justgetflux.com/](https://justgetflux.com/)

~~~
veb
I hope you're not jesting, as this was my first thought. I definitely found it
easier to fall asleep and stay asleep after installing Lux on my tablet, and
phone. Flux for my computer.

If I disabled Flux -- like I just did -- it's awfully painful! Torture! How
did I used to stare at this awfully lit thing for hours on end and expect
sleep to be peaceful?!

On a serious note, it'd be interesting to see whether it's the actual 'light
exposure' that's hindering the sleeping process, or the 'blue light' that
Flux, Lux and others have set out to solve.

~~~
jonah
I am serious. Unfortunately, I don't believe Apple allows the necessary access
to the graphics pipeline. :(

And yes, color is a big part of it. They have a whole section reviewing the
research:
[https://justgetflux.com/research.html](https://justgetflux.com/research.html)

------
thomasfl
I've been looking for a laptop with a kindle like screen and a cool ARM
processor for ages. My brain gets burned by the backlit screen and my lap gets
burned from the steamy hot intel processor. I would be happy to switch to
Ubuntu even if I prefer OSX if this became available.

------
mullingitover
Any kind of bright light at night is going to reduce your melatonin
production. This problem goes all the way back to the introduction of
incandescent lighting, e-readers are just the latest chapter.

~~~
mrob
The retina contains receptors sensitive to blue light, and stimulating them
suppresses melatonin production:
[https://en.wikipedia.org/wiki/Intrinsically_photosensitive_r...](https://en.wikipedia.org/wiki/Intrinsically_photosensitive_retinal_ganglion_cells)
Other frequencies also suppress melatonin production, but less strongly.

If you look at the progression of artificial lighting, from candles, to
incandescent, to halogen incandescent, to fluorescent, to LED, each generation
typically increases both the blue light production and the brightness. Such
strongly blue spectrum isn't an essential feature of the technology, so I
suspect that it's marketing driven because it looks more futuristic.

Additionally, a lot of LED lighting flickers at frequencies that are visible
when you move your eyes via the phantom array effect:
[https://en.wikipedia.org/wiki/Flicker_fusion_threshold#Visua...](https://en.wikipedia.org/wiki/Flicker_fusion_threshold#Visual_phenomena)
I personally find this very annoying, but even if you don't consciously notice
this it's something not found in nature, and I'm not aware of any long term
safety studies.

I'm very skeptical of these changes. Humans have a poor track record of
predicting safety implications of new technology (eg. radioactive materials as
health products, leaded gasoline, etc).

------
SamReidHughes
I use the Kindle app under "sepia" mode to help mitigate this sort of problem,
somewhat. It works much f.lux does, though I don't think it's as extreme as
f.lux's colors.

------
lunarcave
If you really have to read with a backlit display on your iPad or another
device, just get flux[1].

[1] [https://justgetflux.com/](https://justgetflux.com/)

~~~
jkelsey
Can't believe I have to jailbreak my phone to get f.lux on my phone. Love it
on my Mac. Seems so obvious.

~~~
jonah
Lobby Apple.

------
r109
Does it really? After reading 30 minutes of a PDF I knock out! :P

------
shire
is the same case with having my macbook pro on my bed every night before I
sleep?

~~~
veb
Yup. Gives out nasty 'blue light' as spoken about in the article. Try Flux[1],
it'll change your life. If you doubt me, install it and have it run at night
and then after an hour of browsing HN, disable it...

[1] [https://justgetflux.com](https://justgetflux.com)

~~~
shire
wow this is awesome I wish I knew it about a while ago.

------
neindanke
This article is poorly titled. Disappointing since the BBC is capable of
better journalism than this. They should be specific that it is backlit LCD
screens (especially LED backlights since their spectrum is predominantly in
the blue range which simulates morning) rather than what is typically meant
when someone says E-readers, ie: readers that use E-Ink panels which are not
backlit and thus rely on ambient light.

~~~
Kenzo
I agree that BBC is capable of better journalism. This resonates with the
article 'Why so many health articles are junk' posted 5 days ago on HN.
[https://news.ycombinator.com/item?id=8764871](https://news.ycombinator.com/item?id=8764871)

------
stefantalpalaru
The study ignores real e-readers with e-paper displays that mimic dead tree
books extremely well. They also have a sample size of 6 for each of the 2
groups...

