US 9,256,059 B2 — Kana Inoue, Mamoru Terada, Haruo Sato
| 12 elements / 8 groups |
| 18-35mm FX |
| Patent EFL 18.50-34.00mm |
| Patent f/3.6-4.63; marketed f/3.5-4.5 |
| 2 ED-class / 3 aspherical elements |
| Inner focus described; close-focus spacings not tabulated |
Patent inner focus: GrF (surfaces 11-14) moves toward the image side for close focus. The patent gives only infinity-focus zoom spacings, so this transcription models the three infinity zoom positions.
| Element | Type | Glass |
|---|---|---|
| L1 | Negative Meniscus | S-LAL18 (OHARA) class |
| L2r | Composite Aspherical Resin Layer | Composite asphere resin (patent nd=1.51400, vd=53.00) |
| L2 | Negative Meniscus | S-LAL18 (OHARA) class |
| L3 | Negative Meniscus | N-LASF44 (Schott) / 804465 dense lanthanum flint class |
| L3r | Composite Aspherical Resin Layer | Composite asphere resin (patent nd=1.51400, vd=53.00) |
| L4 | Biconvex Positive | S-TIM28 (OHARA) / 689311 dense flint class |
| L5 | Negative Meniscus | S-TIH6 (OHARA) / SF6-class titanium heavy flint |
| C1 | Optical Cement Layer | Optical cement (patent nd=1.51400, vd=42.80) |
| L6 | Biconvex Positive | SF2 (Schott) class |
| L7 | Biconvex Positive ED | S-FPL51 (OHARA) / FCD1-class ED fluorophosphate |
| C2 | Optical Cement Layer | Optical cement (patent nd=1.51400, vd=42.80) |
| L8 | Biconcave Negative | S-LAL18 (OHARA) class |
| L9 | Negative Meniscus | N-LASF44 (Schott) / 804465 dense lanthanum flint class |
| C3 | Optical Cement Layer | Optical cement (patent nd=1.51400, vd=42.80) |
| L10 | Biconvex Positive ED | S-FPL51 (OHARA) / FCD1-class ED fluorophosphate |
| C4 | Optical Cement Layer | Optical cement (patent nd=1.51400, vd=42.80) |
| L11 | Biconcave Negative | S-LAL18 (OHARA) class |
| L12 | Biconvex Positive (2x Asph) | S-BAL42 (OHARA) class |