How is called this peculiar rounded segment display system?
The example in your question shows a text in German, and is either from a bus or streetcar.
This German company makes LCD displays for buses.  The LCD panels appear to be custom made - either ADITECH orders them made that way, or makes them in house.
In any case, they are LCD panels with custom drivers for the unusual &quot;pixel&quot; shapes.
The shapes used in the LCD pixels are based on shapes used in earlier &quot;flip dot&quot; displays.
I have been on buses that used the mechanical flip dots, but that was long ago (more than 20 years.)
If you want that kind of panel, you'll have either order them from an LCD panel manufacturer, or buy a used bus display (if you just want it for a hobby kind of thing.)