PENTAX SMC FA 645 120mm f/4 Macro

US 6,154,324 Example 1 — Murata / Ito

9 elements / 7 groups
120 mm marketed; 123.09 mm patent EFL
F4 marketed; F3.8 patent design aperture
1:1 macro at 0.395 m
All-spherical floating-focus macro

Focus Mechanism

Floating macro focus: the positive front group, aperture stop, and negative rear group move independently toward the object from infinity to 1:1.

Optical Elements (9)

ElementTypeGlass
L1Positive MeniscusS-LAH51 (OHARA)
L2Positive MeniscusS-PHM52 (OHARA)
L3Negative MeniscusS-TIL2 (OHARA)
L4Positive MeniscusS-FSL5 (OHARA)
L5Negative MeniscusS-TIM22 (OHARA)
L6Positive MeniscusS-LAL59 (OHARA)
L7Negative MeniscusS-LAH66 (OHARA)
L8Negative MeniscusS-LAL12 (OHARA)
L9Biconvex PositiveS-LAH51 (OHARA)

Analysis

Detailed analysis available in the interactive viewer above.