WO 2020/136749 A1 — Kosuke Machida, Osamu Gomibuchi, Kenichi Kitano, Mizuki Wayu, Tsuneo Watanabe, Makoto Horikoshi, Ichiro Imaei
| 17 ELEMENTS / 15 GROUPS |
| f = 24.8–67.9 mm |
| F/2.92 |
| 2ω = 85.10°–33.84° |
| 4 ASPHERICAL SURFACES |
Dual-group inner focus: G5 and G6 move independently toward object. Driven by separate stepping motors (STM5 + STM6) on shared barrel member.
| Element | Type | Glass |
|---|---|---|
| L11 | Negative Meniscus | S-TIH53 (OHARA) |
| L12 | Positive Meniscus | S-LAH97 (OHARA) |
| L13 | Positive Meniscus | S-LAH66 (OHARA) |
| L21 | Neg. Meniscus (1× Asph) | M-NBF1 (Hoya catalog equivalent; patent code 744495, supplier unspecified) |
| L22 | Biconcave Negative | S-LAH66 (OHARA) |
| L23 | Biconvex Positive | 728284 - high-dispersion flint (patent nd=1.72825, vd=28.38) |
| L24 | Negative Meniscus | S-PHM52 (OHARA) |
| L31 | Pos. Meniscus (1× Asph) | 694533 - lanthanum crown (patent nd=1.69370, vd=53.32) |
| L32 | Biconvex Positive | 593679 - fluorophosphate crown (patent nd=1.59319, vd=67.90) |
| L41 | Negative Meniscus | 738323 - niobium dense flint (patent nd=1.73800, vd=32.33) |
| L42 | Biconvex Positive | J-FKH1 (Hikari) — ED fluorophosphate crown (498826) |
| L51 | Negative Meniscus | S-NBH8 (OHARA) |
| L52 | Biconvex Positive | 593670 - fluorophosphate crown (patent nd=1.59349, vd=67.00) |
| L61 | Pos. Meniscus (1× Asph) | 792450 — dense lanthanum crown (patent nd=1.79189, νd=45.04; no exact public catalog match) |
| L71 | Positive Meniscus | 946180 - ultra-high-index dense flint (patent nd=1.94595, vd=17.98) |
| L72 | Biconcave Neg. (1× Asph) | M-TAFD305 (Hoya catalog equivalent; patent code 852402, supplier unspecified) |
| L73 | Negative Meniscus | S-BAL35 (OHARA) |