Nikon AI-S Zoom-Nikkor 35–70mm f/3.5 — Optical Cross-Section & Ray Tracing

Home / Lenses / Nikon / Nikon AI-S Zoom-Nikkor 35–70mm f/3.5Nikon AI-S Zoom-Nikkor 35–70mm f/3.5US 4,266,860, Second Embodiment — Nippon Kogaku / Hayashi
10 elements / 9 groups
f = 36.02–68.79 mm design; marketed 35–70 mm
F/3.5 constant aperture
negative-positive two-group zoom
differential L11/L12 close-distance correction
Focus MechanismL11 and L12 move objectward for close focus, with L11 moving farther so D6 increases from 5.7 mm to 6.2 mm; D8 close-focus values are paraxial beta=-0.25 proxy values.
Optical Elements (10)ElementTypeGlass
L1Biconvex Positive603/425 barium flint; Sumita K-BaSF5-equivalent
L2Negative MeniscusS-LAL12 (OHARA), lanthanum crown
L3Negative MeniscusS-LAL8 (OHARA), lanthanum crown
L4Positive MeniscusUnmatched 595/356 light flint class
L5Biconvex PositiveS-BSM16 / SK16 class dense barium crown
L6Negative MeniscusS-TIH6 / SF6 class dense flint
L7Positive MeniscusUnmatched 511/509 light crown class
L8Positive MeniscusN-BK7 / BK7-type borosilicate crown; current OHARA S-BSL7 is not exact
L9Biconcave NegativeS-TIH6 / SF6 class dense flint
L10Biconvex Positive648/338 dense flint; SF12 / FD12 class, exact current catalog identity unresolved
AnalysisDetailed analysis available in the interactive viewer above.

Element	Type	Glass
L1	Biconvex Positive	603/425 barium flint; Sumita K-BaSF5-equivalent
L2	Negative Meniscus	S-LAL12 (OHARA), lanthanum crown
L3	Negative Meniscus	S-LAL8 (OHARA), lanthanum crown
L4	Positive Meniscus	Unmatched 595/356 light flint class
L5	Biconvex Positive	S-BSM16 / SK16 class dense barium crown
L6	Negative Meniscus	S-TIH6 / SF6 class dense flint
L7	Positive Meniscus	Unmatched 511/509 light crown class
L8	Positive Meniscus	N-BK7 / BK7-type borosilicate crown; current OHARA S-BSL7 is not exact
L9	Biconcave Negative	S-TIH6 / SF6 class dense flint
L10	Biconvex Positive	648/338 dense flint; SF12 / FD12 class, exact current catalog identity unresolved