NIKON AI NIKKOR 50mm f/1.8 S — Optical Cross-Section & Ray Tracing

Home / Lenses / Nikon / NIKON AI NIKKOR 50mm f/1.8 SNIKON AI NIKKOR 50mm f/1.8 SUS 4,234,242 A↗, Example 3 — Soichi Nakamura
6 ELEMENTS / 5 GROUPS
50 mm
F/1.8
2ω = 46° (PATENT)
ALL-SPHERICAL
Focus MechanismCONSTRAINED_RECONSTRUCTION: unit focus only. The patent publishes infinity spacing but no focus table; all internal gaps remain fixed and BF changes from 37.1 mm to a code-solved 44.3095517997571 mm at the manufacturer-rounded 0.45 m focal-plane object distance.
Optical Elements (6 physical)ElementTypeGlass
L1Positive Meniscus767468 — J-LASFH2 (HIKARI) coordinate-compatible spectral proxy; production supplier unresolved
L2Positive Meniscus797456 — J-LASF017 (HIKARI) coordinate-compatible spectral proxy; production supplier unresolved
L3Negative Meniscus717295 / SF1-class (supplier unresolved)
L4aNegative Meniscus648338 / SF2-class (supplier unresolved)
L4bPositive Meniscus767468 — J-LASFH2 (HIKARI) coordinate-compatible spectral proxy; production supplier unresolved
L5Biconvex Positive713539 / LAK8-class (supplier unresolved)

Element	Type	Glass
L1	Positive Meniscus	767468 — J-LASFH2 (HIKARI) coordinate-compatible spectral proxy; production supplier unresolved
L2	Positive Meniscus	797456 — J-LASF017 (HIKARI) coordinate-compatible spectral proxy; production supplier unresolved
L3	Negative Meniscus	717295 / SF1-class (supplier unresolved)
L4a	Negative Meniscus	648338 / SF2-class (supplier unresolved)
L4b	Positive Meniscus	767468 — J-LASFH2 (HIKARI) coordinate-compatible spectral proxy; production supplier unresolved
L5	Biconvex Positive	713539 / LAK8-class (supplier unresolved)