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Backlit e-readers 'damage sleep and health'

bbc.co.uk

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Re: Backlit e-readers 'damage sleep and health'

#11

Post by superuser2 »

hollerith wrote: post #10
paulannesley wrote: post #5

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.

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 con…

The Paperwhite's LEDs front-light the display just like a reading lamp front-lights the pages of your book. It may look just like a backlit display, but the distinction is important.

Re: Backlit e-readers 'damage sleep and health'

#12

Post by 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.

Re: Backlit e-readers 'damage sleep and health'

#14

Post by hollerith »

superuser2 wrote: post #11
hollerith wrote: post #10

Earlier quoted context omitted.

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 con…

The Paperwhite's LEDs front-light the display just like a reading lamp front-lights the pages of your book. It may look just like a backlit display, but the distinction is important.

Well, we'll just have to disagree on whether the distinction is important in the current conversation about effects on sleep.

(Kindle paperwhite owner and frequent iPad user here.)

What is it about the photons entering the eye that you imagine makes the "frontlit" display of the Paperwhite better than a backlit LCD display?

Re: Backlit e-readers 'damage sleep and health'

#15

Post by Ironballs »

hollerith wrote: post #10
paulannesley wrote: post #5

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.

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 con…

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...

Re: Backlit e-readers 'damage sleep and health'

#16

Post by 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.

Re: Backlit e-readers 'damage sleep and health'

#19

Post by veb »

jonah wrote: post #7

We just need f.lux[1] for our tablets. [1] https://justgetflux.com/

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.

Re: Backlit e-readers 'damage sleep and health'

#20

Post by stinos »

jonah wrote: post #7

We just need f.lux[1] for our tablets. [1] https://justgetflux.com/

Not sure if that is actually a solution? No studies have been done yet (I think) which investigate if there's a 'safe' threshold for amount of light the screen exposes a person to, under which the effects on sleep etc are absent or extremely small. So for all we know it might be better with f.lux, or the same, can only guess.
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