My lumia 635 has faint vertical lines that slowly fade as I use it, is this normal?

[Windows Central Question]

The lines are not very noticeable really but once you expect to see them you can't miss them. They are most obvious on blue and grey colours never on red. Once the phone warms up they disappear completely and usually don't reappear for hours. The phone is three weeks old so I would return it except that I've just noticed my sister's 630 seems to have the same problem. Has anyone else noticed this? Never saw this on my old 520. Would appreciate any opinions on this.

 

[gpobernardo]

The lines are not very noticeable really but once you expect to see them you can't miss them. They are most obvious on blue and grey colours never on red. Once the phone warms up they disappear completely and usually don't reappear for hours. The phone is three weeks old so I would return it except that I've just noticed my sister's 630 seems to have the same problem. Has anyone else noticed this? Never saw this on my old 520. Would appreciate any opinions on this.

Are those lines visible when your the screen of your (and your sister's) phone is turned off?

 

[Amit Mishra3]

If its not hardware then it could be your screen guard. Try to check it.

 

[mreynolds1]

Thank you for replying, the lines are not visible when the phone is off only when first powered up or woken up then they slowly fade to nothing and everything is fine until I stop using the phone for an hour or more. As for screen saver, I'm not using one right now. I am posting a magnified photo and a screenshot (does not show in screenshot), might help. I'm not even certain I have a problem but would like to know for sure.

 

[gpobernardo]

I see; it looks like the screen needs some "warming up" first for the lines to disappear, but this may need further investigation. Try using the Diagnostic Toolset App or any app that can cycle through the different colors in your screen... the objective is to display a perfectly white image in your screen and see if the lines are specific to a certain area of the screen or if the entire screen is affected. For this purpose, you can also simply save a perfectly white image (R=255, G=255, B=255) in your phone and view it.

In the app, head over to Screen > screen pixels and swipe left or right until you reach the color white. Additionally, you can also see how your screen behaves with different colors.