It looks like one of the many LCD panel failures I've seen over the years.
These panels are sometimes cheap. (Labor, not so much.)
Try this one: http://www.notebookparts.com/lenovo-thinkpad-x1-carbon-lcd-back-cover-00hn934/?gclid=CjwKCAjwmK3OBRBKEiwAOL6t1M29n4q6-OcIF_DMXw7aBphAIEbxXLKRZ8we0nCskiq--XzphKuxZBoCZOIQAvD_BwE appears to show it's in the ballpark as to price.
I am not telling you it's that part. You must verify the part numbers.
Please bear with me, I am a complete novice. Recently I sent my laptop in for repair as the screen went completely dark suddenly as I was using it. The shop has now repaired it, told me there was water damage from the past and they ultrasound-cleaned my logicboard. The screen is working fine, but there is now a significant black patch on the screen. I admit there was water damage from many months ago, but the screen was never damaged like this. There were maybe swirls for a few hours and eventually it dried off, at least there was no lasting visible damage. Is it possible for old water damage to resurface like this? The shop is insisting that it was due to water damage from the past. I'm not sure how to feel about this. Is it possible there was an accident during the repair?
Here's the picture of the black spot: https://imgur.com/higpp6P
In any case I do love the laptop and would probably replace the screen, although the repair costs are adding up. I was looking into replacement screens - the shop quoted me 120€ for cost price for the screen. I seem to find screens going for 80€ online and am wondering if there is something specific I have to look out for. I was googling for LP140WD2-TLE2.
The model: Carbon X1 3448/3Y2
Would be grateful for any feedback.

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