SONY FE 28-70mm f/2 GM

WO 2025/263124 A1 Example 1 — Sony Group / Yamasaki, Yamada

20 ELEMENTS / 14 GROUPS
f = 28.86–67.87 mm
F/2.06
2ω = 73.71–35.36°
10 ASPHERICAL SURFACES (5 elements)

Focus Mechanism

Dual-group floating inner focus: G5 (L51, negative) moves toward image, G6 (L61, positive) moves toward object. Four XD linear motors (two per group).

Optical Elements (20)

ElementTypeGlass
L11Negative MeniscusDense flint (≈S-NPH1W, OHARA; Δnd = +0.0008, probable proprietary melt)
L12Biconvex Positive595686 — fluorophosphate crown (patent nd=1.59489, νd=68.6)
L13Positive Meniscus596670 - fluorophosphate crown (patent nd=1.59561, vd=67.0; no exact public catalog match)
L21Neg. Meniscus (2× Asph)774494 — lanthanum crown (patent nd=1.77373, νd=49.4)
L22Biconcave Negative777297 — dense flint (patent nd=1.77660, νd=29.7)
L23Biconvex Positive930240 — ultra-high-index dense flint (patent nd=1.93024, νd=24.0)
L24Negative Meniscus700555 — barium crown (patent nd=1.69980, νd=55.5)
L31Biconvex Positive (2× Asph)856401 — lanthanum dense crown (patent nd=1.85612, νd=40.1)
L32Biconvex PositiveS-FPL55 (OHARA)
L33Biconcave Negative571560 — barium crown (patent nd=1.57125, νd=56.0)
L41Negative MeniscusS-NPH85 (OHARA)
L42Positive MeniscusS-FPL55 (OHARA)
L43Biconvex PositiveS-FPL55 (OHARA)
L44Biconcave Negative863252 — dense flint (patent nd=1.86252, νd=25.2)
L45Biconvex Positive (2× Asph)856401 — lanthanum dense crown (patent nd=1.85612, νd=40.1)
L51Neg. Meniscus (2× Asph)S-LAM73 (OHARA)
L61Biconvex Positive (2× Asph)S-FPM5 (OHARA)
L71Positive MeniscusS-NPH7 (OHARA)
L72Negative Meniscus863252 — dense flint (patent nd=1.86252, νd=25.2)
L73Negative MeniscusS-LAM73 (OHARA)

Analysis

Detailed analysis available in the interactive viewer above.