The pixel density on that screen is absolutely insane. The screen is about 1x2cm And shows 23 lines of text. At only 8 Px height plus spacing, that's 250x500 pixels and thus 250 Px/cm or >600 PPI. That is in the region of the highest you can get. But those are not in such a tiny form factor. They are 1080p and above. there appear to be super tiny high resolution displays, but I was unable to find any info about them in more credible sources and no microscope images or something like that.