WO 2021/241230 A1 — Hiroki Harada
| 17 ELEMENTS / 15 GROUPS |
| f = 51.29 mm |
| F/1.23 |
| 2ω ≈ 45.6° |
| 3 ASPHERICAL SURFACES |
Dual inner focus (floating). F1 (L21–L22, weak negative) and F2 (L31–L32, strong positive with 2 aspheres) move toward object independently via two STM stepping motors. Front group A and rear group R are fixed. F1 leads F2 by ~1.6 mm differential travel.
| Element | Type | Glass |
|---|---|---|
| L11 | Negative Meniscus | S-BSM81 (OHARA) |
| L12 | Positive Meniscus | FDS18 (HOYA, patent nd/vd match; E-FDS1-W relabel) |
| L13 | Negative Meniscus | J-KZFH4 (HIKARI catalog-equivalent; production supplier unspecified) |
| L14 | Positive Meniscus | FCD505 (HOYA) / J-PSKH1 |
| L15 | Biconvex Positive | FCD505 (HOYA) / J-PSKH1 |
| L16 | Positive Meniscus | FCD505 (HOYA) / J-PSKH1 |
| L17 | Positive Meniscus | FCD505 (HOYA) / J-PSKH1 |
| L18 | Biconvex Positive | FCD505 variant / S-FPM2 |
| L19 | Biconcave Negative | S-NBH53V (OHARA, patent nd/vd match) |
| L21 | Negative Meniscus | S-NBH8 (OHARA) |
| L22 | Plano-Convex Positive | FCD505 variant / S-FPM2 |
| L31 | Biconvex Pos. (1× Asph) | FCD505 variant / J-PSKH1 |
| L32 | Biconvex Pos. (1× Asph) | S-LAH96 (OHARA, patent nd/vd match) |
| L41 | Positive Meniscus | S-PHM52 (OHARA) |
| L42 | Biconvex Positive | J-LASFH9 (Hikari, patent nd/vd match) |
| L43 | Biconcave Negative | N-KZFS4 (SCHOTT catalog equivalent; production supplier unspecified) |
| L44 | Biconcave Neg. (1× Asph) | J-BK7 (Hikari; exact Nikon patent coordinate match) |