[One (M8) Q&A, Help & Troubleshooting] GedBlake:
Hi, guys...

After spending fours years tinkering around with budget to mid-range Android devices, last month I decided to treat myself to a top-of-the range, flagship device... and four weeks ago I bought (off contract) the HTC One M8. And I am absolutely delighted it with it:)... it is truly an amazing piece of technology:).

However, a few days ago, when cleaning the screen, I noticed a mark... which I just assumed was a finger mark or something. I wiped it away, and it was gone...

...or so I thought...

A day or so later, I notced that the mark had returned... in exactly the same place. It's in the very upper right hand corner of the screen, to the right of the front facing camera and to the left of the SD card tray.

The mark is in the shape of an elongated 'S'.

--------------------------------------------------------------------------------

A few things puzzle me about this mark or blemish...

** It can only be easily seen in specific lighting conditions, ie., when the light source is hitting the screen at an oblique angle...

** It's less noticeable in natural daylight, then in artificial light...

** It's totally invisible when that of part of the screen has just been cleaned.

In other words, in order to see this mark/blemish, I have to deliberately 'dirty-up' that part of the screen. Either by rubbing the screen with my thumb or finger to leave some sweaty residue, or by lightly breathing on the screen, the way one would on a pair of spectacles in order to clean them. Indeed, this was how the blemish came to my attention. I normally lightly breathe on the screen, and then wipe it with a soft microfiber cloth. I suspect that the presence of finger grease or breathed water vapour is altering the refractive index of the glass, such that reflected light is making this blemish or flaw visible. But that's just an educated guess... it's been 35 years since I studied optics for my physics 'O' level at school. Funny how some things stay with you though:).

--------------------------------------------------------------------------------

I have appended three screenshots of this strange blemish or mark. It should be noted that getting these shots was extremely difficult, as the light source had to be angled obliquely to the screen of the M8 for the mark to become clearly visible to the camera I was using. I took over sixty shots, and these are the best three.

Ironically, and despite these difficulties, these three shots make the blemish look much worse than it actually is. In normal use, I've got to look really hard for the blemish to actually see it. If you didn't know it was there, you likely wouldn't see it... or you'd just dismiss it as a smudge of grease.

--------------------------------------------------------------------------------

So, what exactly could this mark or blemish be?

A manufacturing defect of some kind?; Some natural flaw in the Gorrilla Glass?

If this is indeed the case, then I can relax and live with it. The mark is borderline invisible anyway, and doesn't impact my normal use of the device in any way.

Unless it's the portender of something much more serious, such as...

A fracture inside the glass? - And this is what worries me:(.

It's not a crack (yet... and it may never be)), and when I run my finger nail over the area affected, I can not detect a crack. The glass feels consistently smooth. Whatever it is, it's 'inside' the glass itself.

However, if it is a fracture, then what are the chances of it propagating into a full blown crack at some point in the future?

Have any XDA members seen anything similar on other devices they've owned?

Should I pre-emptively initiate RMA proceedings with HTC before it does becomes a crack? Or am I worrying unnessarily? I know I can get a little OCD/obsessive about details like this, and I tend to loose perspective a little.

So... any thoughts, insights, recommendations or advice would be warmly welcomed.

Thanks in advance.

Rgrds,

Ged.