CANON EF 28-135mm f/3.5-5.6 IS USM

US 6,061,180 — Shingo Hayakawa

16 elements / 12 groups
28-135mm f/3.5-5.6 marketed; 28.891-131.182mm patent design
135 full-frame / Canon EF
One GMo asphere; unit II inner focus; unit V optical IS

Focus Mechanism

Inner focus by complete negative unit II moving objectward; close-focus spacings are a first-order reconstruction constrained to Canon's 0.5 m minimum focus distance.

Optical Elements (16 physical)

ElementTypeGlass
L1Negative MeniscusS-TIH53 (OHARA)
L2Positive MeniscusS-LAL14 (OHARA)
L3Positive MeniscusS-LAL8 (OHARA)
L4Negative MeniscusS-LAH55V (OHARA)
L5Biconcave NegativeS-LAH65V (OHARA)
L6Biconvex PositiveS-TIH53 (OHARA)
L7Biconcave NegativeS-LAH55V (OHARA)
L8Negative MeniscusS-TIH53 (OHARA)
L9Biconvex PositiveS-BSM14 (OHARA)
L10Biconvex PositiveS-NSL36 (OHARA)
L11Biconcave NegativeS-LAH55V (OHARA)
L12Positive MeniscusS-TIH6 (OHARA)
L13Biconcave NegativeS-BAH27 (OHARA)
L14Biconvex PositiveS-BAH28 (OHARA)
L15Biconvex Positive (1× Asph)L-BAL42 (OHARA)
L16Negative MeniscusS-TIH53 (OHARA)