How are all these lenses produced? Are they still processed the same as as the originals?

Have heard they are frit painted, then convex formed in a mould using heat and natural gravitation. Possibly they're silk screen or flat glass painted, then moulded as some have suggested?

Has the manufacturing process changed over the years? Has or does anyone use the pad printing process?

what about the more recent and much smaller, one piece mini display globes? Are their faces just painted or silk screened on?