NIKON AF-S NIKKOR 28mm f/1.4 E ED

JP 2017-227799 A — Yasunari Fukuda, Akiko Furuta, Toshinori Take, Takayuki Sensui

14 ELEMENTS / 11 GROUPS
f ≈ 28.4 mm
F/1.45
2ω ≈ 75.4°
4 ASPHERICAL SURFACES (3 ELEMENTS)
2 ED ELEMENTS (S-FPM2)

Focus Mechanism

Rear-group unit focus: Gr2 (8 elements, L21–L28 + stop) translates 6.28 mm toward the object. Gr1 fixed. Constant barrel length.

Optical Elements (14 physical; 15 modeled media)

ElementTypeGlass
L11Negative MeniscusS-TIM28 (OHARA)
L12Negative MeniscusN-LAK8 (Schott)
L12rNegative Meniscus (1× Asph)UV-curing resin (composite)
L13Biconvex PositiveS-TIH53 (OHARA)
L14Biconcave NegativeN-BAK4 (Schott catalog-equivalent; patent supplier unspecified)
L15Biconvex PositiveS-LAH58 (OHARA)
L16Biconvex PositiveS-LAH66 (OHARA)
L21Positive MeniscusS-LAL18 (OHARA)
L22Biconvex PositiveS-LAL14 (OHARA)
L23Biconvex PositiveS-FPM2 (OHARA)
L24Biconcave NegativeJ-KZFH9 (Hikari)
L25Biconcave Negative806333 — dense flint (patent coordinate; vendor unresolved)
L26Biconvex Pos. (1× Asph)L-LAH90 (OHARA)
L27Biconvex PositiveS-FPM2 (OHARA)
L28Pos. Meniscus (2× Asph)S-LAL13 (OHARA)