Comment by eqvinox

Contrary to the "highlights" section (which seems to be the only place calling it a "standard" 19-core optical fiber), this is not in fact a 'standard' fiber, rather the origin seems to be the standard (125µm) diameter ("Sumitomo Electric was responsible for the design and manufacture of a coupled 19-core optical fiber with a standard cladding diameter (see Figure 1)"). Looks like the "diameter" simply got lost for the highlights section.

(Nonetheless impressive, and multi-core fiber seems to be maturing as technology.)