Database Develop

Slight screen flicker?

I have a nook color, I was wondering if anyone notices a very slight screen flicker like a low refresh rate? Most people would not notice. It doesn't bother me much but I wanted to see if its normal. I notice it most on a dark grey background at 50 percent or lower brightness.
Sent from my HTC Vision using Tapatalk

Yes! finally someone that notices it! I have been posting this on other forums. I notice it too on dark backgrounds with about 20-40% brightness, Not sure if it can ever be fixed with an update, but it is sometimes annoying, although not highly noticeable.

I have worked with computer enough that I can tell the refresh rate of a crt just by looking at it. If its normal I am not to worried I justed wanted to know if it was defective because ill switch it out before I root it.
Sent from my HTC Vision using Tapatalk

I get the same thing, very noticeable when you are changing the brightness setting. I use the lowest brightness to read an eBook, and I can really notice the flicker when I lower the brightness, but I can notice it when I get back to the reading screen.

I see it on darker images...its so subtle I ignore it.
Sent from my NOOKcolor using Tapatalk

I still have mine stock... but I see it as well.
Anyone that has loaded any other apps notice it in those apps? i.e. does it flicker noticably in Angry Birds? or other apps?
thanks.
J

I wonder if it being an IPS screen has anything to do with it. It doesnt bother me to much but causes more eye strain than reading from my htc g2. You would think they would make sure an ebook reader doesnt flicker. oh well i can deal with it.

sdelcegno said:
I wonder if it being an IPS screen has anything to do with it. It doesnt bother me to much but causes more eye strain than reading from my htc g2. You would think they would make sure an ebook reader doesnt flicker. oh well i can deal with it.
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It's not the screen, per se, but the LED's that are lighting it up. From what I've read, LED's can't vary output with respect to voltage (they're not dimmable), so you have to pulse them very fast to change the output. I assume that the lower the "level" the more the LED is off vs. on, hence the flicker.
Dang I can't post links yet...
Go to Wikipedia, and look for :
/wiki/Backlight#Flicker_due_to_backlight_dimming
I'm pretty sensitive to this, but haven't noticed it on my iPad, but apparently it does it as well. I was wondering why the stock lowest brightness levels were so friggin' bright - probably at the threshold of flicker. You can dim more in a browser or ebook app, which is where I see reports of flicker.
Go to Discussions dot apple dot com
/thread.jspa?threadID=2398784
Another reason why I like my old CCFL IPS 12" ThinkPad X32!
-Dan

While you can dim an LED by limiting the current (either via inline resistors or with constant current drivers), you can only do so to a degree. Below a certain current, they will simply not light even though the current goes through the LED. On high performance LED's this is still at a pretty bright level. So instead you use PWM (Pulse Width Modulation) and vary the duty cycle to brighten and dim the LED. As the PWM is at a fixed frequency, with more or less of the cycle being lit or unlit, once the unlit portion becomes substantially longer than the Lit part, you can detect the "Flicker" if you are sensitive to it. This is usually particularly noticeable in the "corner of the eye" if you pan you vision across the area and the device gets paned across you field of vision.
This is done on all the new LED tail lights on cars as well and I hate seeing them at night, when they are almost making me nauseous from the flicker.

Good info thanks. Makes sense but wonder why I don't notice on my led backlit netbook. Guess every screen is different.

yea I really wish there was an update to fix this, but i guess it's just the screen, funny how I have never noticed this on any LCD screen I have ever had from computer to TV

three nook colors - my experience with flicker
My first nookColor had screen flicker, also a mind of its own with phantom taps. Nook #2. Did not have noticeable screen flicker but did have a handful of stuck pixels. Took it back and picked up #3. No stuck pixels, but I've got screen flicker on dark colors. Find it strange that nook #2 didn't have te problem with the flicker. I don't like the flicker at all but think it may be timento live with it.

flicker
Has any one returned a flikering nook color and gotten a better one in return?

Hello, I am having a similar problem with angry birds. My screen sometimes will flash different colors and today the screen stayed completely red for 2 or 3 seconds while playing the game. But other than that I love the rooted nook color. Maybe the graphics chip is not powerful enough for this game.

Firmware update
What you described with angry birds is not the problem I am having. Mine is screen flicker. My eye can basically detect the refresh rate with low brightness or in darker colors.
Tried to change it out. Would say that Best Buy is much easier to exchange things at than Barnes & Noble. Eventually they switched mine out and the new one had a dead pixel. They then let me open two more in store in the store all had dead pixels, so did their display model. All presented in the lower right hand corner of the screen. Would be covered up by the black menu bar normally, but visible when the black menu bar goes away.
Anyway I kept my flickering nook, and talked to someone at Barnes and Noble tech support on the phone. He told me the dead pixels were new to him, but they knew about screen flicker issues. He said they would be releasing a firmware update to address this and other problems very soon.
Just wanted to note that none of these nook colors were rooted.

Yes, same here, I have that on my Witstech A81 (resistive screen) too, more noticeable when the battery level drops. Never noticed this problem on my iPhones or iPad though...can't be Android related can it?

glacon said:
What you described with angry birds is not the problem I am having. Mine is screen flicker. My eye can basically detect the refresh rate with low brightness or in darker colors.
Tried to change it out. Would say that Best Buy is much easier to exchange things at than Barnes & Noble. Eventually they switched mine out and the new one had a dead pixel. They then let me open two more in store in the store all had dead pixels, so did their display model. All presented in the lower right hand corner of the screen. Would be covered up by the black menu bar normally, but visible when the black menu bar goes away.
Anyway I kept my flickering nook, and talked to someone at Barnes and Noble tech support on the phone. He told me the dead pixels were new to him, but they knew about screen flicker issues. He said they would be releasing a firmware update to address this and other problems very soon.
Just wanted to note that none of these nook colors were rooted.
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Thanks. I can see the flicker too on gray screens. I have no other issues though (minus a tiny, tiny bit of give on the bottom bezel). I'll wait and hope it gets fixed in an update. I don't have a lot of time to keep exchanging a good unit.

If it is a known issue and a firmware fix is planed, then I am content with my rooted nook. Thanks for this thread.

I took mine back to B&N today to see if replacing it would fix it. Both store displays didn't have any flicker.
They opened two different nooks and they did the same flickering thing.
So I called Nook technical support. He put me on hold for about 5 minutes. He said he checked about 5 nooks and they all flickered. But he hadn't noticed it before.
So, he will put a ticket into the development team to have it looked at.
So, another confirmation that Nook tech support is aware and looking into it.

My first Nook did not display this behavior. I returned it due to creaking issues, and the replacement did display screen flicker.
I'm hoping it's a firmware issue and not a hardware one!
Currently not a big deal though...

[Q] using i9003 slcd on i9000 (burn-in replacement)

Hi fellas,
We know our SGS is old but it still is very much capable. One thing with this device that can't be worked out is the amoled burn-in. I had my SGS's screen replaced twice due to burn-in, and some of you might think that "you've had your brightness settings too high for a long time" etc. The thing is, I've been using lowest brightness setting since I had the second replacement and for over a year burn-in still take effect. I know SAMOLED is superior in terms of overall display experience but the way I use my phone isn't the same as I use it when I first had it (meaning I'm used to looking at my screen and I don't bother the contrast/deep blacks anymore as I used to). I wanted to have a peace of mind using the device for long (4) hours browsing the web or playing a game or using an app without constantly timing in my mind that the status bar or clock is now a little more burned than yesterday, something like "at this duration use, you're blue subpixel is 0.00001% weaker". Those who suffer the agony of watching a burn-in on their displays understand this. So I was thinking of replacing my screen again with the SLCD from i9003 and I wonder if someone already tried it out or if it is possible?

answer
Project1.exe said:
Hi fellas,
We know our SGS is old but it still is very much capable. One thing with this device that can't be worked out is the amoled burn-in. I had my SGS's screen replaced twice due to burn-in, and some of you might think that "you've had your brightness settings too high for a long time" etc. The thing is, I've been using lowest brightness setting since I had the second replacement and for over a year burn-in still take effect. I know SAMOLED is superior in terms of overall display experience but the way I use my phone isn't the same as I use it when I first had it (meaning I'm used to looking at my screen and I don't bother the contrast/deep blacks anymore as I used to). I wanted to have a peace of mind using the device for long (4) hours browsing the web or playing a game or using an app without constantly timing in my mind that the status bar or clock is now a little more burned than yesterday, something like "at this duration use, you're blue subpixel is 0.00001% weaker". Those who suffer the agony of watching a burn-in on their displays understand this. So I was thinking of replacing my screen again with the SLCD from i9003 and I wonder if someone already tried it out or if it is possible?
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Hi!
did you get any answer on this topic?
I have the sam preblem, i have a Samsung i9000b (the same screen as i9000), and i can get a scren from a samsung i9003.
Have you tried making the replacement with the other screen?
Thanks! have a nice day

display brightness

Greetings,
Just received a used device and noticed my unit won't physically lower in brightness at around 25 percent. What I mean is that at around the 25 percent mark, I am unable to perceive it getting any lower when set at a lower percentage. I've also noticed that when I have the brightness at a high percentage and then quickly lower it to the minimum, that the display will at first be quite dim then will suddenly raise itself to a slightly brighter minimum. I do not have auto brightness on, nor any filter apps active while testing. Just wondering if this issue is isolated to my device. Thank you for reading my concern. If anything is unclear, I could try taking a video of the issues. Anyone else with these issues? I've searched the web to no avail.

i just bought a used device as well and mine has the same issues. the backlight seems to flicker on the second screen at low brightness and below about half the second screen is noticably dimmer. its unfortunate that they didn't put a lot of effort into the screen software or quality considering its the main gimmick of this phone, but it is made by ZTE after all. the price you probably paid for one of these things is a lot more representative of the quality than the original MSRP. But its still a fun gimmick even with all the flaws.

stevegalaxius said:
i just bought a used device as well and mine has the same issues. the backlight seems to flicker on the second screen at low brightness and below about half the second screen is noticably dimmer. its unfortunate that they didn't put a lot of effort into the screen software or quality considering its the main gimmick of this phone, but it is made by ZTE after all. the price you probably paid for one of these things is a lot more representative of the quality than the original MSRP. But its still a fun gimmick even with all the flaws.
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Thanks for your thoughts and input. Yeah this is quite unfortunate on how the phone turned out. I also see the flicker on the second display. But as you mentioned, the device is indeed quite fun. I'm actually thoroughly enjoying the device especially with books and comics reading in the extended mode. I tend to do some late night reading, so that was the reason why I brought up the display issue as I had wanted to get the display as dim as possible before applying a filter. Hopefully one day we'll get root to check out if we can lower the display minimum brightness level along with other lower level system modifications.

axxtran said:
Thanks for your thoughts and input. Yeah this is quite unfortunate on how the phone turned out. I also see the flicker on the second display. But as you mentioned, the device is indeed quite fun. I'm actually thoroughly enjoying the device especially with books and comics reading in the extended mode. I tend to do some late night reading, so that was the reason why I brought up the display issue as I had wanted to get the display as dim as possible before applying a filter. Hopefully one day we'll get root to check out if we can lower the display minimum brightness level along with other lower level system modifications.
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apparently a few weeks ago someone released TWRP for this device. its not quite a root but it still gives you root access to change the build.prop and some low level system settings. TWRP is the sign that there is some kind of development happening but i wouldn't hedge your bets on anybody fixing the screen issues even with some kind of kernel modification

stevegalaxius said:
apparently a few weeks ago someone released TWRP for this device. its not quite a root but it still gives you root access to change the build.prop and some low level system settings. TWRP is the sign that there is some kind of development happening but i wouldn't hedge your bets on anybody fixing the screen issues even with some kind of kernel modification
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That is definitely a most welcome update. I'm curious on what build your device is on since you mentioned having similar issues to mine. I am on b30 myself and will be flashing to b37 when I get a chance to see if there are any differences.

Weird glitch when phone is in dark mode (colour shifting when taping display)

Hi everyone,
Got my Pixel 4 XL on the 23rd and been playing around with it since then. I am now settling into a rhythm and noticed a very concerning glitch with the display when the phone is in dark mode. Basically, when the phone is in dark mode I noticed that typing in Gboard or tapping anywhere on screen in apps that are not pure black (such as Messages, Phone, etc.) will shift the screen colour from blueish-black to greenish-black. This happens every time, even after rebooting the device. There is no visible colour shifting in apps that use pure-black such as Settings (however, parts of Settings like the search bar that are the "gray" dark colour also shift). Once I noticed this happening now I cannot stop noticing it everywhere. I am looking to find out from you whether you are seeing the same thing or whether this may be a device problem. Note that the same issue shows up in dark apps even if dark mode is not enabled. It also has nothing to do with Ambient EQ, Automatic Brightness, or anything else of similar nature. Occasionally the problem stops, but if I pull up Gboard and start typing (say to search in the Recent section of the phone app) the problem immediately comes back.
I am looking for serious feedback here from those willing to look closely. This does seem like a software glitch to me, rather than hardware, especially since I am not seeing this behaviour with any other colours and so far it definitely has something to do with physical interaction with the screen when tapping on it. As I said, it also seems to be universally triggered by Gboard when in apps running in dark mode.
I appreciate any feedback you can provide.
Edit: Looks like what I'm observing is related to the switching colour profiles when the display is going back and forth between 60Hz and 90Hz. Turning off the smooth display function or forcing the display into permanent 90Hz mode appears to stop the problem from happening. Google really messed this one up. I hope their 90Hz fix they promised clears up this issue. Very annoyed ?
Thanks,
Dejan

Btw, since you are using forced 90hz display make sure to have always on display on. If you don't your greys will be purple and lower brightness as well as lots of black smear/crush. I don't know how turning on always on display solved that issue (someone posted this fix in another thread). So it indeed doesn't seem to be hardware but software related and hopefully they will tune this over time.

zetsumeikuro said:
Btw, since you are using forced 90hz display make sure to have always on display on. If you don't your greys will be purple and lower brightness as well as lots of black smear/crush. I don't know how turning on always on display solved that issue (someone posted this fix in another thread). So it indeed doesn't seem to be hardware but software related and hopefully they will tune this over time.
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Yeah, I saw that thread. Some funky stuff going on with display calibration and 90Hz. Since I know that the HW is not defective and the SW is the source of the issue I am less bothered now (I cannot stand exchanging HW). I haven't specifically observed that effect on my phone and while I did try forcing 90Hz, I actually went back to the stock setting since I noticed that forced 90Hz further sucked down the battery that already is not particularly stellar despite this being the XL version. I presume Google will refine the 90Hz calibration and function over the next few months. I will say though that I am a bit confused why they need to have different calibration at different refresh rates. I calibrate all of my desktop monitors and despite the fact that I have a 100Hz monitor I never have to change calibration with refresh rate. Maybe an OLED thing :shrug:

dhorgas said:
Hi everyone,
Got my Pixel 4 XL on the 23rd and been playing around with it since then. I am now settling into a rhythm and noticed a very concerning glitch with the display when the phone is in dark mode. Basically, when the phone is in dark mode I noticed that typing in Gboard or tapping anywhere on screen in apps that are not pure black (such as Messages, Phone, etc.) will shift the screen colour from blueish-black to greenish-black. This happens every time, even after rebooting the device. There is no visible colour shifting in apps that use pure-black such as Settings (however, parts of Settings like the search bar that are the "gray" dark colour also shift). Once I noticed this happening now I cannot stop noticing it everywhere. I am looking to find out from you whether you are seeing the same thing or whether this may be a device problem. Note that the same issue shows up in dark apps even if dark mode is not enabled. It also has nothing to do with Ambient EQ, Automatic Brightness, or anything else of similar nature. Occasionally the problem stops, but if I pull up Gboard and start typing (say to search in the Recent section of the phone app) the problem immediately comes back.
I am looking for serious feedback here from those willing to look closely. This does seem like a software glitch to me, rather than hardware, especially since I am not seeing this behaviour with any other colours and so far it definitely has something to do with physical interaction with the screen when tapping on it. As I said, it also seems to be universally triggered by Gboard when in apps running in dark mode.
I appreciate any feedback you can provide.
Edit: Looks like what I'm observing is related to the switching colour profiles when the display is going back and forth between 60Hz and 90Hz. Turning off the smooth display function or forcing the display into permanent 90Hz mode appears to stop the problem from happening. Google really messed this one up. I hope their 90Hz fix they promised clears up this issue. Very annoyed ?
Thanks,
Dejan
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I just noticed this on my pixel 4 xl tonight. But It only happens when the proximity sensor is triggered. Ex: like after making a phone call except it made everything on the screen seem over saturated on the screen and well as the same color shift you had stated. It seems to go away once I lock the device and unlock it again. It did it with smooth display on and off as well as force 90hz on and off.

There are a couple threads discussing this. Here's one of them:
https://forum.xda-developers.com/pixel-4-xl/how-to/smooth-display-colour-issues-t4000087
And another:
https://forum.xda-developers.com/showthread.php?t=3998907
Sent from my Pixel 4 XL using Tapatalk

Low Brightness Flicker (LineageOS & Stock too?)

Hi, sorry if this was posted before, but with XDA moving to XenForo, search seems messed up, i did several searches and nothing comes up for "flicker" in this whole Pixel 4 XL Forum...
Has anyone else dealt with the low brightness screen flicker? I know it can't be just a bad phone, since i just bought three pixel 4 XL phones and they all exhibit this same behavior.
They are all running LineageOS (Official builds) so I don't know if this just affects the ROM or stock as well (although I've read it might affect stock phones too elsewhere).
It makes the phone pretty difficult to use in very low light situations, the screen will constantly flicker (more noticeable on darker backgrounds).
At first I thought it was just the Opera browser (as that's what I prefer), but it's operating system wide... Apps like "Darker" help.... because you can crank up the phone brightness and use a filter to dim the screen.... but it doesn't get the top & bottom menu/buttons, so those remain like spotlights in your eyes with that workaround.
Just curious if anyone knows whats up with this... it's the only phone I've ever seen this behavior on (and i've used Pixel 1,2,3 XL phones all with Lineage, and a myriad of other devices back in the Cyanogenmod days.... I've never seen a screen flicker issue like this).
Thanks for any help
edit / update-
the pro version of "darker" app works to fix this.... you crank the phones brightness to 100% and with the pro version you can dim the rest of the interface.
hopefully this helps anyone else suffering from this HUGE flaw (again i don't know if its just LineageOS or not, i didn't run stock on these except to unlock bootloader etc)

Hi,
I've seen it once and solved it by switching off smooth display. Not a real solution of course, but I never really noticed the difference between 90Hz and 60Hz anyway.

edwinek said:
Hi,
I've seen it once and solved it by switching off smooth display. Not a real solution of course, but I never really noticed the difference between 90Hz and 60Hz anyway.
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hmm.... you running stock i guess? i don't see smooth display option in lineage