OLYMPUS E.ZUIKO AUTO-T 100mm f/2.8

US 3,749,478, Example 2 — Jihei Nakagawa, Sumio Nakamura

5 ELEMENTS / 5 GROUPS
DESIGN f = 100 mm
DESIGN F/2.8
ALL SPHERICAL
PATENT f = 1 SCALED × 100

Focus Mechanism

Static at infinity. The patent gives no focus motion or close state, so the model carries none. Olympus's catalog gives a 1 m minimum focus and an automatic correction mechanism for close distances, which the model does not include.

Optical Elements (5 physical)

ElementTypeGlass
L1Positive MeniscusS-BAL35 (OHARA catalog equivalent; production supplier unspecified)
L2Positive MeniscusBAL22 (OHARA catalog equivalent; production supplier unspecified)
L3Positive MeniscusBASF7 (SUMITA catalog equivalent; production supplier unspecified)
L4Negative MeniscusPBH23 (OHARA catalog equivalent; production supplier unspecified)
L5Positive MeniscusPBH23 (OHARA catalog equivalent; production supplier unspecified)