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Photos: https://photos.app.goo.gl/BvqLVYkMBB7RjaMU7 (Nexus 9 Android tablet)

My daughter's tablet is enclosed in a full-body case, so it's fairly well protected. Still, somehow, at some point I noticed these bubbles and took the case apart -- only to realize that they were not caused by a liquid spill between the cover's window and the display, but rather are within the display!

How on earth did this happen? What's going on? (And if this is not for EE, then please point me elsewhere. Not Android I'm sure, but probably not Physics either?)

I'm not really looking for a fix (unless one readily exists) mainly because the thing works fine still and is "only" a child's toy.

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closed as off-topic by Bimpelrekkie, dim, Dmitry Grigoryev, RoyC, Dave Tweed May 28 at 14:51

This question appears to be off-topic. The users who voted to close gave this specific reason:

  • "Questions on the use of electronic devices are off-topic as this site is intended specifically for questions on electronics design." – Bimpelrekkie, dim, Dmitry Grigoryev, Dave Tweed
If this question can be reworded to fit the rules in the help center, please edit the question.

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    \$\begingroup\$ Isn't it just the plastic protective screen/cover any touch screen device comes with that should be peeled off? (In case of kids using the device, I'd replace is by a more robust screen protector) \$\endgroup\$ – Huisman May 27 at 9:18
  • \$\begingroup\$ This is actually a really interesting question, because problems can occur when the bonding between layers of display is bad. Usually, there's a separate display, with a touchscreen glued onto it, and if the gluing procedure isn't good enough, bubbles can form, and sometimes cause touchscreen artifacts and so on. \$\endgroup\$ – AndrejaKo May 27 at 9:26
  • \$\begingroup\$ @Huisman That's just the thing -- the full-body enclosure has a plastic "window" atop the LCD, but when I take the tablet out, it has no other screen protector. \$\endgroup\$ – KlaymenDK May 27 at 9:26
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    \$\begingroup\$ Bubbles that are included during assembly can be very small and not be spotted. With time as they flatten out they get large and obvious. Sometimes the various layers are assembled in a vacuum fixture and any bubbles are vacuum and when pressure returns they shrink and disappear in an ideal world. The fact that they are in such a neat line does point towards something happening during assembly. \$\endgroup\$ – KalleMP May 27 at 10:14
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There is a piece of glass on the front of the device (called a digitizer) and then the LCD is sandwiched up against that glass.

What your picture looks like is that something has gotten in between the glass and the LCD. You could probably fix it by opening the device and cleaning/re-seating the LCD against the glass.

As to how did it happen, difficult to say. Possibly what ever glue or mechanism that holds the bottom of the LCD to the glass has come loose. Maybe from impact/shocks or just age. If it's fairly new, then I would start thinking about manufacturing errors.

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    \$\begingroup\$ as I understansd it you need a vacuum oven and special clamps to attach the digitiser to the LCD, probably not a DIY task. \$\endgroup\$ – Jasen May 27 at 10:37
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    \$\begingroup\$ @Jasen depends on the construction. Plenty of them are just glued around the edges and/or held down with brackets. \$\endgroup\$ – hekete May 27 at 10:41

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