US 2026/0056396 A1 — Takeru Uehara
| 12 elements / 11 groups |
| Patent f = 12.36-27.16 mm |
| Marketed 12-28 mm f/3.5-5.6 |
| 1 ED element / 1 aspherical surface |
| GVR cemented VR doublet; G3 inner focus |
Inner focus by the single-element third group G3. Close-focus gap values are not published for Example 1; this data file retains infinity zoom spacings for both focus endpoints.
| Element | Type | Glass |
|---|---|---|
| L11 | Positive Meniscus | N-BK7 (Schott) / BK7-class crown (516/641) |
| L12 | Negative Meniscus | N-LASF44 (Schott) / 804465 lanthanum flint class |
| L13 | Biconcave Negative | N-LASF44 (Schott) / 804465 lanthanum flint class |
| L14 | Positive Meniscus | S-TIH53 (Ohara) / SF57 dense flint class (847/238) |
| L21 | Biconvex Positive | N-BK7 (Schott) / BK7-class crown (516/641) |
| L22 | Positive Meniscus | F5 (Schott) / 603380 flint class |
| L23 | Biconcave Negative | S-TIH53 (Ohara) / SF57 dense flint class (847/238) |
| L24 | Biconvex Positive | J-FKH1 (Hikari, 498826) ED fluorophosphate |
| L25 | Negative Meniscus | J-LASFH15 (Hikari, 950294) ultra-high-index lanthanum flint |
| L26 | Pos. Meniscus (1× Asph) | S-BAL35 (Ohara, 589612) barium crown |
| L31 | Biconcave Negative | NBFD13 (Hoya, 806407) lanthanum flint |
| L41 | Positive Meniscus | J-LASF021 (Hikari, 850324) dense lanthanum flint |