NIKON AF-S DX ZOOM-NIKKOR 18-70mm f/3.5-4.5G IF-ED

US 2005/0068636 A1 — Satoshi Hayakawa

15 elements / 13 groups (physical count)
18-70mm f/3.5-4.5 (production)
18.7-67.9mm f/3.6-4.6 (Example 1)
3 ED elements / 1 aspherical element (production)
G2 internal focus
Nikon F / DX

Focus Mechanism

CONSTRAINED_RECONSTRUCTION: the patent specifies G2 focusing but no close-focus spacings. Close states are code-solved at Nikon's 0.38 m MFD with a fixed image plane and rigid G2 translation (D5 += delta, physical D14 -= delta). G2 shifts objectward by 1.415523 mm at 18.7 mm, 2.234433 mm at 35.0 mm, and 4.721413 mm at 67.9 mm; the tele state gives paraxial |m| = 0.160020 versus Nikon's marketed 0.16 maximum reproduction ratio.

Optical Elements (15 physical; 16 modeled media)

ElementTypeGlass
L11Negative Meniscus (convex to object)847238 class
L12Positive Meniscus (convex to object)S-BSM81 catalog equivalent (patent 640601; production supplier unspecified)
L13Positive Meniscus (convex to object)713539 class
L21rHybrid Aspheric Resin Layer (1x Asph)Unmatched (hybrid aspheric resin; patent nd=1.55389, vd=38.1)
L21Negative Meniscus (convex to object)804466 class
L22Biconcave Negative804466 class
L23Biconvex PositiveJ-LAFH3 catalog equivalent (patent 795285; production supplier unspecified)
L24Negative Meniscus (concave to object)804466 class
L31Negative Meniscus (convex to object)804396 class
L32Biconvex PositiveJ-FKH1 catalog equivalent (patent 498826; production supplier unspecified)
L33Biconvex Positive487704 class
L41Positive Meniscus (concave to object)847238 class
L42Biconcave Negative835427 class
L51Positive Meniscus (concave to object)J-FKH1 catalog equivalent (patent 498825; production supplier unspecified)
L52Biconvex PositiveJ-FKH1 catalog equivalent (patent 498825; production supplier unspecified)
L53Negative Meniscus (concave to object)805254 class