JP 2003-329924 A↗2003Assignee: Tamron Co., Ltd.Inventors: Yuichi MuramatsuTAMRON SP AF 180mm f/3.5 Di LD [IF] MACRO 1:1 (B01)— 14 ELEMENTS / 11 GROUPS, PATENT f = 176.9587 mm; DATA SCALED TO 180 mm