Bausch & Lomb and Hasselblad
14 and 11 researched events on one shared scale. Bausch & Lomb 1853–present, Hasselblad 1841–present.
The axis stretches where either maker has research and collapses where neither does, so a year sits opposite the same year on both. Event counts differ because research depth differs, not because one company did less.
Bausch & Lomb1853–present · 14 events · 2 concurrent threads
Hasselblad1841–present · 11 events · 2 concurrent threads
Read either maker on its own: Bausch & Lomb · Hasselblad