I remember there’s an app in China that has a QR code on screen all the time that is basically invisible to users unless you tune the color scale in a certain way, I forgot what it was for specifically but I imagine it was for tracking the screenshots taken and uploaded by users.
WoW was spotted doing that in 2012. It contained information like the server IP, the account ID, and a timestamp. As far as I know, Blizzard has never commented on it, but one theory is that it's for troubleshooting purposes when a player reports a problem and includes a screenshot.
Looks like the iPhone one is only physically on the glass so wouldn't affect screenshots (unless you were photographing it with a very high resolution camera device).
> According to the report, the bar codes are engraved on the iPhone’s glass at different stages of manufacturing. [...] These codes are described as being “the size of a grain of sand” and, unsurprisingly, can only be seen with special equipment.
Apple did not invent the serial number. Good grief.
You should read the article
The article really doesn't explain anything. If Apple wanted to serialize their screen glass, why not just slap a sticker on it? The article doesn't explain why. How does this reduce the defect rate? Also not explained.
There's a linked article from "The Information" that I suspect goes into more detail, but it's paywalled.
> why not just slap a sticker on it? The article doesn't explain why. How does this reduce the defect rate
A sticker would be noticable. Apple has forced the lens suppliers to add a laser mark with a serial number as they are created, by looking at what serial number screens get through to final production they can see how many get broken/fail to meet tests etc. It doesn't in it self reduce the defect rate, but lets Apple know what the defect rate is, which for some reason the manufacturers are reluctant in telling Apple
> lets Apple know what the defect rate is, which for some reason the manufacturers are reluctant in telling Apple
My suspicion is that an unknown but nontrivial share of the 'defects' were of the 'fell off a truck' variety rather than a true production problem.
Alternatively, Apple might have contracts that pay its suppliers 'cost plus', such that Apple is on the hook for used supplies without giving the vendors a direct financial incentive to reduce defect rate.
Every now and then I visit the internet without an adblocker to see how bad it’s getting.
In this case, there’s barely a paragraph of text between each ad. And even that text is super light on details.
It felt like they took the title and massaged it into an article.
They don't want to violate the copyright of the actual article. https://www.theinformation.com/articles/how-a-hidden-bar-cod...?