Bausch & Lomb and Konica
14 and 12 researched events on one shared scale. Bausch & Lomb 1853–present, Konica 1873–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
Konica1873–present · 12 events · 2 concurrent threads
Read either maker on its own: Bausch & Lomb · Konica