SONY FE 28-70mm f/3.5-5.6 OSS

US 2015/0077859 A1 Example 4 — Kanetaka / Nagamatsu, Sony

28-70mm f/3.5-5.6
9 elements / 8 groups
3 aspherical elements / 5 aspherical surfaces
1 ED element
Optical SteadyShot production lens

Focus Mechanism

Inner focus by the single negative third group (G8). The patent gives infinity spacings only; close-focus spacings are paraxial finite-conjugate solves to the official endpoint MFDs, with mid-zoom MFD interpolated.

Optical Elements (9)

ElementTypeGlass
G1Negative MeniscusS-LAH55V (OHARA) / TAFD5G class, 835427
G2Biconcave NegativeS-LAM2 / LaF2 class, 744447-448
G3Positive MeniscusE-FDS1 (HOYA) / N-SF66 class, 923209
G4Biconvex Positive (2× Asph)L-BAL42 class (OHARA low-Tg / moldable barium crown), 583594
G5Biconvex Positive EDFCD1 (HOYA) / S-FPL51 class, 497816
G6Biconcave NegativeE-FD7 (HOYA) / S-TIM27 class, 640346
G7Biconvex Positive (2× Asph)L-BAL42 class (OHARA low-Tg / moldable barium crown), 583594
G8Biconcave Negative (1× Asph)L-LAL13 / S-LAL13 class (OHARA), 694532
G9Positive MeniscusE-LAF7 (HOYA) / H-LaF4 class, 750350

Analysis

Detailed analysis available in the interactive viewer above.