JP 2023-183894 A Example 1 — Sigma / Yamamoto
| 14 ELEMENTS / 11 GROUPS |
| f = 48.72 mm |
| F/1.45 |
| 2ω = 46.49° |
| 3 ASPHERICAL LENSES (5 SURFACES) |
| 1 SLD ELEMENT |
Single-element inner focus. L8 (GR1) — negative meniscus with 2× aspherical surfaces — translates toward image. GF, stop, and GR2 fixed. HLA linear motor drive.
| Element | Type | Glass |
|---|---|---|
| L1 | Biconvex Positive | E-FDS1 (HOYA) |
| L2 | Biconcave Negative | E-CF6 (HOYA) |
| L3 | Biconcave Negative | S-TIH6 (OHARA) |
| L4 | Biconvex Positive (2× Asph) | 764491 — aspherical mold glass (no exact public catalog match; patent nd=1.76450, νd=49.10) |
| L5 | Biconvex Positive | FCD515 (HOYA) — SLD fluorophosphate crown |
| L6 | Negative Meniscus | E-FD15 (HOYA) |
| L7 | Biconvex Positive | S-LAH58 (OHARA) |
| L8 | Neg. Meniscus (2× Asph) | Aspherical mold glass (592/670, FCD505 class) |
| L9 | Biconvex Positive | J-LASKH2 (Hikari, 755523 lanthanum crown) |
| L10 | Negative Meniscus | NBFD25 (HOYA, 855252) |
| L11 | Biconvex Positive | TAFD55 (HOYA) |
| L12 | Biconvex Positive | FDS18 (HOYA, ultra-dispersive flint) |
| L13 | Biconcave Negative | S-TIM2 (OHARA) |
| L14 | Neg. Meniscus (1× Asph) | S-TIM28 (OHARA) |
Detailed analysis available in the interactive viewer above.