E-ink screen technology, something is off!

[ProDigit]

They've always said that e-ink screens are magnetic...
Well, holding a magnet to the screen should reverse polarity of the screen pixels, but it doesn't even disturb them...


What I did notice, is when keeping it aimed towards the sun, that completely white (or black) e-ink color on the screen, tends to turn into a mesh; with vertical and horizontal lines on them.

What is it about UV light, that triggers the screen, that a magnet or incandescent bulb can't do?

[Cinisajoy]

Source please?
Where did you read this?

[ProDigit]

Personal experience.

[Cinisajoy]

Ok I had never heard they were magnetic, now what I had heard was there is a magnet for waking it up and putting it to sleep with a cover.
So was just curious where you had read ereaders would attract magnets.

[PeterT]

I think you'll find this is a repeat of a post from ProDigit from a few years back. I think the advice given was that it is electrostatic based and not magnetic based.

[rem736]

on the sony prs-505, i did notice that if the screen is in direct sunlight, the portion of the screen in sunlight shows text that is less saturated than the portion in the shade. so it's more gray than black. but that was the viz plex screen. i don't think it happens with the newer screens.

[ApK]

Remembering that electromagnetism is a single force, I wouldn't be surprised if some excessive application could have some effect, but they are not 'magnetic' in any practical sense.
As for bright direct sunlight, these screens contain fluid chemicals. It wouldn't surprise my if direct sunlight had an effect. It turns many of my LCD displays black until they cool down.

[ProDigit]

Yes, in the past I've noticed this on my PRS-505, and was thinking that perhaps by now, people figured out why the device actually changes under sunlight.

Haven't tried PPW (because was stolen), or any of the nooks yet.

I recently found another E-ink device, a generic chinese e-ink reader, I might enjoy using for a while, but has no glo light, and has a 5" screen!

[JSWolf]

When Vizplex screen where being made, some were made by LG. Some of these LG screens were defective in that if under direct sunlight, the screen would not update properly and you would get parts of the screen that was faded. This is not normal and is a defect int he screen. Sony had screens that had this issue and so did Amazon. I've actually seen this defect with a Sony Reader my Mother owned.

[Purple Lady]

Originally Posted by JSWolf

When Vizplex screen where being made, some were made by LG. Some of these LG screens were defective in that if under direct sunlight, the screen would not update properly and you would get parts of the screen that was faded. This is not normal and is a defect int he screen. Sony had screens that had this issue and so did Amazon. I've actually seen this defect with a Sony Reader my Mother owned.

Onyx also had this problem. My old Boox 60 had it but I rarely read in the sun so I didn't try to return it.

[ProDigit]

It took about 5 or 10 minutes in full sunlight, before the issue became apparent.
And the screen resets after every screen refresh.

[Dulin's Books]

the defect was a lack of UV filter layer in the display stack

[JSWolf]

Originally Posted by Dulin's Books

the defect was a lack of UV filter layer in the display stack

I've never read before what the defect was only what triggered it. Thanks for that.

[ProDigit]

Any more explanation on how UV light can trigger these screens?

I think I once tried UV light (LED) on them, but the screen didn't change. I noticed that unlike real paper, this screen does not light up under UV (or black) light.

[Dulin's Books]

Originally Posted by JSWolf

I've never read before what the defect was only what triggered it. Thanks for that.

yeah i've had to look back through notes, emails and posts to recall it all. The displays were built by PVI not LG. PVI apparently did a whole run of displays without the proper filter layer.

basically it boiled down to PVI leaving out a filter that blocked some light getting to the TFT backplane. the materials used to create the backplanes are photoconductive. too much uv causes current leakage, the current is what flips the eink capsules from black to white and the grey tones. leaving one layer off might not be a problem for LCD panels used for laptops or other LCD displays. but eink panels are more often used in full sun. PVI actually argued for awhile that the displays were "in spec" but when I talked with them at SID display week in May of 2010 they acknowledged their mistake.

I think they were truly embarrassed to have not realized the issue sooner or to catch it in QC.