LEICA SUMMILUX 28 mm f/1.7 ASPH.

US 2016/0266350 A1 Example 1 — PANASONIC IPM / IIYAMA & SUEYOSHI

11 ELEMENTS / 9 GROUPS
f ≈ 27.08 mm
F/1.76
2ω ≈ 79.9°
3 ASPHERICAL ELEMENTS (5 SURFACES)

Focus Mechanism

Floating inner focus: G2 (doublet) and G4 (singlet) move toward object. Macro mode (M2) extends G1–G4 as a unit to 0.17 m.

Optical Elements (11)

ElementTypeGlass
L1Biconcave NegativeS-BAL42 (OHARA)
L2Biconvex PositiveS-LAH58 (OHARA)
L3Biconcave NegativeS-TIM5 (OHARA)
L4Biconvex PositiveL-LAM60 (OHARA)
L5Positive MeniscusS-LAH79 (OHARA)
L6Pos. Meniscus (1× Asph)S-LAH63 (OHARA)
L7Negative MeniscusS-TIH14 (OHARA)
L8Biconcave NegativeS-NBH55 (OHARA)
L9Biconvex PositiveS-LAH58 (OHARA)
L10Pos. Meniscus (2× Asph)S-LAH66 (OHARA)
L11Neg. Meniscus (2× Asph)H-ZF52A (CDGM)

Analysis

Detailed analysis available in the interactive viewer above.